**1. Introduction**

For decades, marketing scholars and practitioners have investigated the influence of globalization on consumer behavior across countries, particularly in connection with issues of worldwide marketing standardization–adaptation [1,2]. According to [3], market convergence has encouraged sociologists, psychologists, and marketers to examine the interaction of global and local influences on consumer behavior in the context of globalization. As Ref. [4] defined, global consumer acculturation is the effect of culture on consumer behavior. Therefore, it is vital to research the impact of individual cultural features on consumers' behavior, even if the study concentrates on single cultural characteristics and does not include studies of how the complex total influences purchasing and consumer behavior (p. 785).

Due to advancements in communication technology, information has spread far and wide, giving businesses and goods a global audience. As the Internet has been more widely accepted and used, customers from across the globe have access to more goods and services through safe online purchasing [5]. New transportation technologies have offered customers more accessible access to other countries, where they may immediately interact with foreign goods and advertising. These exposures have impacted customer expectations and product selections across many attributes [6]. E-commerce has grown in popularity because of improved Internet technology. Consumers now have quick access to the product information on the Internet and may use shopping channels to make online purchases [7].

The development of the Internet has established a tight relationship with producers and consumers, locally and internationally. All these participants have become important and conscious contributors to sustainable consumption [8]. Although there is no agreement about the sustainable consumption definition, one of the most accepted, presented in 1994, defines it as "the use of goods and services that respond to basic needs and bring a better quality of life, while minimizing the use of natural resources, toxic materials and

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emissions of waste and pollutants over the life cycle, so as not to jeopardize the needs of future generations" [9]. In that sense, the expansion of e-commerce has influenced those changes and emerged along with sustainable development. Therefore, its significance has been considered to have an extraordinary impact on the modern world [10]. Sustainable development establishes the paradigm of economic growth by integrating it with environmental protection criteria [11], considering current and future generations' needs, and acknowledging the connection of its three dimensions: Environmental, Social, and Economic [12].

Evidence suggests that consumers in emerging nations are less ethnocentric [13]. They highly prefer imported goods from developed countries [14]. One significant factor contributing to this occurrence is prestige. Consumers often utilize the Country of Origin (COO) as a quick indicator when deciding whether or not to buy goods and brands made in the target nation [15]. Hence, many studies on the COO's impact on customer behavior have developed in international marketing and business literature [16].

Corporations working based on online retail and e-commerce implement strategies to attract consumers to their brands and product lines, facilitating online shopping and bidirectional communication with their customers. Undoubtedly, corporations should consider, in all senses, the importance of e-commerce sustainability and sustainable regulations when creating offers, processes, and marketing strategies [17].

Previous statements are important due to the fact that e-commerce may assist in achieving a sustainable competitive advantage, which contributes to the long-term stability of the ecological system. According to [18], there is a link between perceived sustainability and customer engagement in e-commerce, and by reducing the number of visits to the store, e-commerce shopping may help to encourage environmentally-friendly lifestyles [19].

Consumer ethnocentrism (CE) has become progressively essential to researchers in consumer behavior and international marketing because it directly influences consumers' attitudes and buying preferences. An example of ethnocentrism is when a person desires to explore their identity and belong to a group/community [20]. Purchasing foreign goods is considered harmful because it is detrimental to the home economy, unpatriotic, and has a damaging influence on domestic jobs [21]. CE has a moral basis that extends beyond economic and functional concerns. Some customers think buying foreign goods is disloyal and immoral since it harms the native economy and destroys employment. Highly ethnocentric customers often make erroneous judgments and overvalue local items relative to imported goods [22] Thus, understanding customer behavior in various settings is critical for international marketing. As markets grow borderless and completely interconnected, it is crucial to determine if customers are concerned about the COO of goods and to what degree countries and cultures favor local goods over international ones.

Even though many researchers have investigated CE in various countries and have concentrated on CE results, little is known regarding the proportional relevance of its effects on the COO and Theory of Planned Behavior (TPB). What is more, there is a lack of explicitly evaluating consumer behavior through internet purchases during a pandemic in this framework. Nevertheless, there is mounting evidence that COO and CE are significant determinants of product assessments and purchasing choices [23,24]. Consequently, this research emphasized the roles of COO and CE in understanding consumer purchasing behavior. Thus, the current study attempts to expand the TPB model by incorporating key online purchasing variables, such as COO and CE, and improving our capacity to forecast intention and explain online consumers' choices. As a result, this research develops and examines a theoretical framework based on the TPB model to examine the connection between variables and explain online consumer behavior during pandemics.

The present study adds to the body of knowledge in a variety of ways. First, it may fill a knowledge gap in COO and CE research by examining online consumer responses during pandemics. Second, we create an experimentally tested model that explains the links between COO and CE and predicts online local and international brand purchase decisions using the TPB. Finally, we conduct an experimental evaluation of the model using data from a representative sample of a developing country to see if the indicated relationships hold.

Partial least squares structural equation modeling (PLS-SEM) is now well-established as a method for analyzing complex causal relationships among latent variables [25]. Moreover, this analysis method has been used extensively in many contexts, particularly in international marketing [26]. In this study, this approach is used to validate the theoretical framework.

The remaining document is organized as follows. The subsequent section sets out the conceptual framework and hypothesis. Afterward, measurements and procedures are discussed. Next, the empirical results are examined. Finally, we discuss the implications for theory and practice, highlight limitations, and provide suggestions for further study.

#### **2. Conceptual Framework and Research Model**

#### *2.1. Consumer Ethnocentrism*

Ethnocentrism, or more broadly, in-group prejudice, is a prevalent empirical phenomenon in human cultures. For example, Ref. [27] refers to CE as the beliefs held by consumers about the appropriateness, indeed morality, of purchasing foreign-made products. Highly ethnocentric consumers refuse to buy imported products and may even chastise others for doing so [28]. The impact of ethnocentrism extends not only to businesses or governments but also to the consumer level, on which most of the academic study has concentrated.

CE refers to preferences for home over international goods in marketing research [27]. The idea is helpful in forecasting customer receptivity to foreign brands [3]. For consumers and strategic decision-makers in the global economy, assessing CE levels is critical since doing so may indicate where standardization is feasible and specialized services are required [29] (p. 58). Aspects such as global positioning [30], market entry mode decisions [31], and the materialization of COO effects [32] are also influenced by CE [33]. CE's impact has often been theorized in terms of social identity theory, in which customers are seen as actors motivated to adhere to and align themselves with the standards and values of their in-groups in the hopes that doing so will provide them with a good social image [34].

Despite its many theoretical and practical uses and repeated requests for conceptual revision, the CE construct has remained unchanged since 1987. According to [35], it has been suggested by many scholars that CE must be conceptually reexamined, along with its quantification. The rise in calls is due to empirical data contradicting the original conception of CE as a unidimensional phenomenon [36]. The Consumer Ethnocentrism Tendencies Scale (CETSCALE) is utilized to operationalize the concept, which raises questions regarding the measurement's relevance and generalizability [27]. On the other hand, Ref. [37] indicated that many researchers linked the CETSCALE to social desirability bias, response style bias, and the dimensionality issues raised in previous research.

Shimp and Sharma [27] coined CE as American consumers' views about the propriety, even morality, of purchasing foreign-made goods. According to these authors, from the ethnocentric consumer's viewpoint, buying imported goods is terrible since it harms the home economy, results in job losses, and is unpatriotic. CE was quantified using the CETSCALE, created by these researchers. All the scale's items indicate a preference for USmade goods over foreign-made goods and a rejection of purchasing or importing foreign goods. As a result, it has been utilized successfully throughout the globe (e.g., [38], with acceptable reliability and validity.

Ethnocentrism is a broad concept that encompasses all aspects of ethnicity. Ethnicity is a prehistoric human social identity. For example, Ref. [39] specifies that it is still one of people's most significant social identities, since it fulfills fundamental psychological requirements and has an evolutionary foundation because it is concerned with family groupings and genetic similarities. According to [27], CE derives from Summer's [39] broad notion of ethnocentrism. In other words, CE seems to be a narrow application and adaption of ethnocentrism to the purchase of imported consumer goods. Therefore, CE originated from the broader notion of ethnocentrism [37] (p. 382). However, the two concepts are different, and CE is best understood considering generic ethnocentrism. On the other hand, Ref. [40] suggested that CE may mean many other things, such as beliefs, dispositions, or characteristics. Hence, it is best understood as an attitude and socialpsychological construct. CE may fulfill the requirements of ethnocentrism by strengthening ethnic group strength by purchasing goods from the nation where their ethnic group resides. However, it is probable that CE may not flow directly from ethnocentrism, but that multiple categories mediate the connections.

On the other hand, non-ethnocentric customers compare the quality and performance of international and local goods and select the best one [27]. According to [41]'s research on ethnocentric sentiments in consumer behavior, there is a general dislike of imported goods, making it difficult for them to succeed in foreign marketplaces. In today's more globalized society, cosmopolitan attitudes are believed to decrease ethnocentric sentiments. However, Ref. [27] found that CE promotes patriotism and stresses cultural and ethnic identity, affecting the global economic environment, particularly in times of crisis. Consistent with the study of [42], the desire to help local businesses typically rises during economic crises in many nations.

Subsequent ethnocentrism research has concentrated on the willingness to pay for foreign goods and the intention to buy and attitudes about foreign products [43]. In the same vein, Ref. [44] said that CE is associated with a negative attitude toward foreign goods, and, at the same time, the desire to buy domestically is positively impacted. In the opinion of [45], the explanation for this conclusion is that consumers' cultural values significantly influence consumer behavior. On the other hand, Ref. [46] stated that customers choose imports from nations with similar cultural backgrounds to their own. Thus, CE significantly impacts purchasing habits for domestic and foreign products, with particular attention to market segmentation, communications processes, and methods, defining the correct target markets, and creating a unique selling proposition that can be decoded by consumers nationally. Therefore, we hypothesized:

**Hypothesis 1 (H1).** *High consumer ethnocentrism will produce lower online consumer purchase behavior.*

**Hypothesis 2 (H2).** *Consumer ethnocentrism positively influences country of origin.*


**5. Plant-growth-promoting rhizobacteria (PGPR): an ecologically sustainable alternative to chemical fertilizers for agricultural production**

The rhizosphere is a well-defined ecological niche that consists of the volume of soil surrounding plant roots and is home to a wide range of microbial species [61, 62]. As a result of phytomicrobiome research, certain plant-microbe interactions that directly aid in plant nutrition are beginning to emerge [63]. Microbes have the power to positively influence plant growth and combat the majority of modern agriculture's challenges, making them a promising alternative for agricultural sustainability. The rhizomicrobiome is indispensable for agriculture because of the extensive diversity of root exudates and plant cell debris that attract diverse and unique patterns of microbial colonization. Fertilizer requirements are often lower in soils with dynamic microbial ecologies and rich organic matter than in traditionally treated soils [64].

Despite the fact that the rhizosphere is home to a diverse range of microbes, including bacteria, fungi, algae, protozoa, and actinomycetes, bacterial colonies are predominant [65, 66]. The bacterial community in the soil, in particular, has the potential to proliferate quickly and use a wide variety of nutrient sources. A group of natural soil bacterial flora that resides in the rhizosphere and grows in, on, or around plant roots [67] and has a beneficial effect on the plant's overall health is referred to as PGPR [68]. PGPR is a nonpathogenic, beneficial bacterium that promotes plant growth by modifying hormone levels and nutritional requirements, as well as reducing stress-related damage [69]. Nutrient absorption is thought to be increased as a result of the increased root surface area mediated by PGPR. Besides, they mineralize organic contaminants and are employed in polluted soil bioremediation [70]. When compared to other microorganisms, PGPR has unique characteristics, such as the ability to synthesize growth regulators, nitrogen fixation, phosphorus solubilization, siderophore generation, nutrients, and mineral solubilization, demonstrating their exceptional tendency in stimulating plant growth [71]. They are also environmentally friendly and ensure that nutrients from natural sources are available at all times. In addition to stimulating plant growth through their active mechanisms, the bacterial

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

colonies in the rhizosphere have a considerable influence on suppressing phytopathogenic microorganisms. Beneficial rhizobacteria can emit antibiotics and other chemicals that are effective at inhibiting pathogens [72].

The fundamental impacts that rhizosphere bacteria have on plants have evolved into an important mechanism for protecting plant health in an environmentally sustainable manner [73]. They participate in a variety of biotic activities in the soil ecosystem to keep it active and productive for farming systems [74]. Furthermore, in recent times, PGPR has garnered much attention for its potential to substitute agrochemicals for plant growth and yield through multiple processes, including decomposition of organic matter, recycling of essential elements, soil structure formation, production of numerous plant growth regulators, degrading organic pollutants, stimulation of root growth, and solubilization of mineral nutrients, which are important for soil health [75]. It is cost-effective and environmentally beneficial to replace chemical fertilizers with PGPR, as well as to identify the most effective soil and crop management approaches in an attempt to develop more sustainable farming and soil conservation fertility [76]. The employment of phytomicrobiome representatives as a long-term disease prevention and nutrient supplement method in farming production might help to reduce the negative impacts of pesticide usage [77]. The inoculated plant's biocontrol and induction of disease resistance, biological N2 fixation, phosphate solubilization, and/or phytohormone synthesis are all potential explanations for PGPR's growth-promoting actions [78].

PGPR has both direct and indirect modes of action as a biofertilizer and a biopesticide.

#### **6. The effect of PGPR on plant nutrient supplementation**

#### **6.1 PGPR as biofertilizers**

One of the most prevalent ways for increasing agricultural production is to improve soil fertility. PGPR promotes soil fertilization through the biofixation and biosolubilization processes (**Figure 2**).

#### *6.1.1 Biofixation of atmospheric nitrogen*

Nitrogen (N) is found in all forms of life and is one of the most significant mineral nutrients for plant growth as it is a crucial component for various physiological activities in plants, including photosynthesis, nucleic acids, and protein synthesis [80]. Unfortunately, due to the low degree of reactivity, no plant species are capable of directly converting atmospheric dinitrogen into ammonia and using it for growth, hence making the plants dependent on biological nitrogen fixation (BNF). Nitrogen fertilizer, as being the most effective approach to nitrogen supplementation, has been an integral part of modern crop production and agricultural systems; yet, their continued and undesirable use is contaminating the climate. Though carbon dioxide (CO2) is widely regarded as the primary cause of climate change, nitrous oxide (N2O), which has a 265-fold higher heat-trapping efficiency than CO2 [81], is indeed a significant contribution. PGPR in this regard is a potential alternative to minimize the fertilizer requirements to a certain degree as the majority of the plant microbial community can either directly fix atmospheric nitrogen through legume-rhizobium interaction or indirectly by helping nitrogen fixers via their secretion [82].

**Figure 2.** *PGPR's mechanism of action [79].*

Worldwide, total N fixation is estimated to be ∼175Tg, with symbiotic nitrogen fixation in legumes accounting for ∼ 80 Tg by fixing 20–200 kg N year-1, while the remaining nearly half (∼88 Tg) is industrially fixed during the production of N fertilizers [83]. The most prominent symbiotic nitrogen fixer is Rhizobium [84], whereas Azospirillum, Acetobacterdiazotrophicus, Azotobacter, Herbaspirillum, Cyanobacteria, Bacillus, Paenibacillus, Gluconacetobacter, and Azoarcus, etc., represent the free-living N fixers [85].

Symbiotic nitrogen fixation: A mutualistic association between a microorganism and a plant is known as symbiotic nitrogen-fixing. The N-fixing symbiosis between rhizobia and legumes is the most well-studied and utilized beneficial plant-bacteria interaction. In this interaction, legumes supply rhizobia with reduced carbon and a protected, anaerobic environment that is necessary for nitrogenase activity, while rhizobia feed legumes with biologically accessible nitrogen. The bacteria enter the root first, causing the growth of nodulation, which converts atmospheric nitrogen into usable forms (primarily NH3) [86]. Rhizobia can fix up to 200 kg of nitrogen ha − 1 by establishing symbiotic relationships with more than 70% of leguminous plants, thus making it available to plants.

Free-living nitrogen-fixing: Several nitrogen-fixing microorganisms do not interact in a symbiotic manner. These microorganisms are free-living and rely on plant leftovers or their own photosynthesis to exist. Although free-living nitrogen fixers do not enter the plant's tissues, a tight interaction is developed where these bacteria reside close enough to the root that the atmospheric nitrogen fixed by the bacteria is taken up by the plant, resulting in greater nitrogen absorption. Besides, other bacteria that do not fix nitrogen have been demonstrated to boost nitrogen uptake in plants, resulting in increased nitrogen use efficiency [87], most likely due to increased root development, which allows plants to reach more soil [63]. Evidence of PGPR involvement in the plant N budget has been identified for various plants, particularly sugarcane [88].

Rhizobial N-fixation is an integrated approach for disease control, growth stimulation, as well as providing and maintaining the nitrogen level in agricultural soils

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

around the world, thus minimizing the need for extensive N-fertilizer application and limiting the soil and environmental challenges associated with it.

#### *6.1.2 Phosphate solubilization*

Phosphorus (P) is the most significant vital element in plant nutrition (N), alongside nitrogen [89]. It is involved in a number of major metabolic activities in plants, including macromolecular biosynthesis, photosynthesis, respiration, energy transfer, and signal transduction [90]. Although most soils hold a significant amount of phosphorus, which builds over time as a consequence of fertilizer treatments, plants have access to only a small portion of it. Despite the fact that P is abundant in both organic and inorganic forms in the soil, only 0.1% of it is available to plants because 95–99% of phosphate is either insoluble, immobilized, or precipitated [91]. Plants can absorb mono and dibasic phosphate on their own, but organic and insoluble phosphate must be mineralized or solubilized by microorganisms [92]. Phosphate anions are highly reactive and, depending on the soil quality, can be trapped by precipitation with cations including Mg2+, Ca2+, Al3+, and Fe3+. Plants cannot absorb phosphorus in these forms because it is highly insoluble. As a result, plants only get a small percentage of the total.

When deficient, phosphorus-based fertilizers are typically used to replenish soil P, which is readily available to plants. Supplementing P with commercial fertilizers, however, is not an ideal option due to their high cost and sometimes inaccessibility to plants since they are easily lost from the soil and subsequently mix with local streams, contaminating both terrestrial and aquatic environments [93]. Therefore, phosphorus solubilization, in addition to nitrogen fixation, is also vital biologically. Phosphate solubilization is among the most profound consequences of PGPR on plant nutrition. Persistent plant growth, PGPR, plays a major role in solubilizing phosphorus [94]. The potential of various bacterial species to solubilize insoluble inorganic phosphate compounds such as dicalcium phosphate, tricalcium phosphate, rock phosphate, and hydroxyapatite has been documented by many researchers. Phosphate can be dissolved in insoluble forms by a variety of PGPR, including Pseudomonas, Bacillus, and Rhizobium. PGPR solubilizes P by employing a number of mechanisms, including the synthesis of organic acids and extracellular enzymes, to make use of inaccessible forms of P, hence assisting in the availability of P for plant absorption. Miller et al. [95] pointed out two processes—acidification of the external medium via the release of low molecular weight organic acids (such as gluconic acid) that chelate phosphate-bound cations and the formation of phosphatases/phytases that hydrolyze organic forms of phosphate compounds. Phosphorus solubilizing bacteria (PSB) has been shown to lower the recommended P dose by approximately 25% [96] and is even more efficacious when combined with other PGPRs or mycorrhizal fungi, reducing the P supplementation to 50%. As a result, the risk of P runoff and eutrophication is mitigated [97].

#### *6.1.3 Solubilization of potassium*

Potassium (K) deficit has become a severe crop production bottleneck.  Soluble potassium concentrations in soil are typically low; over 90% of the potassium in the soil is in the form of insoluble rocks and silicate minerals [98]. Several microbes, particularly fungal and bacterial genera, have close connections with plants and can release potassium in accessible form from potassium-bearing minerals in soils through the synthesis and secretion of organic

acids [99–101]. Setiawati and Mutmainnah [101] synthesize organic acids produced by soil microorganisms, such as acetate, ferulic acid, oxalate, coumaric acid, and citrate, which significantly increase mineral dissolution rates and proton production by acidifying the soil rhizosphere and resulting in mineral K solubilization. As a result, using potassium-solubilizing PGPR as a biofertilizer in agricultural production can reduce agrochemical use while also encouraging environmentally friendly crop production.

#### *6.1.4 Iron sequestration by siderophore production*

Iron (Fe) is a major bulk mineral abundantly available on Earth, yet it is inaccessible in the soil for plants, owing to the fact that Fe3+ (ferric ion), the most common form of Fe found in nature, is hardly soluble [102]. PGPRs are the right fit to address this issue as they produce siderophores, which are tiny organic compounds that increase Fe absorption capability when it is scarce. Since PGPR can form siderophores, they are a valuable asset in supplying the plant with the necessary iron. Siderophores released by PGPRs boost plant growth and development via facilitating access to Fe in the soil surrounding the roots [103]. Plant growth can be stimulated directly by siderophore-producing bacteria, which improves plant Fe intake, or indirectly by suppressing the activities of plant pathogens in the rhizosphere, which limits their Fe availability [104]. Pathogen suppression is induced by the synthesis of siderophores, which decrease pathogen survival by chelating available Fe and therefore restricting pathogen survival [105]. In the presence of other metals, such as nickel and cadmium, a robust siderophore, such as the ferric-siderophore complex, is crucial for Fe uptake by plants [106]. Siderophores alleviate stress on the plants caused by potentially hazardous metals, such as Al, Cd, Cu, Pb, and Zn, found in polluted soil via forming stable compounds with them [107]. This phenomenon is beneficial for reducing plant stress induced by potentially harmful metals found in contaminated soils. Furthermore, siderophore-expressing rhizobacteria could be a potential alternative to chemical fertilizers by concurrently addressing salt-stress effects and Fe limitation in saline soils.

#### *6.1.5 Exopolysaccharide synthesis or biofilm formation*

One of the many advantages of rhizobacteria in encouraging plant growth and controlling plant diseases is their ability to synthesize polysaccharides. Multifunctional polysaccharides, for instance, structural polysaccharides, intracellular polysaccharides, and extracellular polysaccharides, are synthesized by specific bacteria. Exopolysaccharide production is critical for biofilm development, and root colonization can influence microbial interactions with root appendages. The colonization of plant roots by EPS-producing bacteria aids in the separation of free and insoluble phosphorus in soils, circulating critical nutrients to the plant for appropriate growth and development, as well as protecting it against disease attacks. EPS-producing bacteria have a variety of roles in plant-microbe interactions, including protection against desiccation, stress [108], adherence to surfaces, plant invasion, and plant defense response [109]. Plant exopolysaccharides produced by plant-growth-enhancing rhizobacteria are critical in stimulating plant growth because they act as an active signal molecule during beneficial interactions and generate a defense response during the infection phase [110]. Some plant-growth-promoting rhizobacteria that produce exopolysaccharides can also bind cations, including Na+, implying that they may play a role in limiting the amount of Na + available for plant uptake and thereby reducing salt stress [111].

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

#### **6.2 Production of biostimulants by PGPR**

Phytohormones, commonly known as plant growth regulators, are organic chemicals that, at low levels (less than 1 mM), promote, inhibit, or modify plant growth and development [112]. Phytohormones are categorized based on where they act. Botanists recognize five main kinds of phytohormones: Auxins, Gibberellins, Ethylene, Cytokinins, Ethylene, and Abscisic acid.

Phytohormones stimulate root cell proliferation by overproducing lateral roots and root hairs, resulting in increased nutrition and water intake [113]. This is crucial for regulating nutrient uptake depending on soil composition and environmental circumstances. Slower primary root development and a spike in the proportion and length of lateral roots and root hairs are the most common effects.

Phytohormones play an important role in regulating developmental processes and signaling networks that are involved in plant adaptation to a variety of biotic and abiotic stressors [114]. Abiotic stressors, however, disrupt plant growth by altering endogenous levels of phytohormones [115]. Surprisingly, some bacteria, such as PGPR, may stimulate plants to produce phytohormones.

A diverse spectrum of rhizospheric microorganisms is capable of producing growth hormones that can promote cell proliferation in the root architecture by inducing an increase in nutrition and water intake by encouraging root hair growth, thus regulating overall plant growth and development, as well as activating pathogen defensive responses [116]. Important biological rhizobacteria can adjust to their surroundings and develop stress tolerance by repairing plant roots. The production of growth metabolites by PGPRs may help provide water stress resistance in host root colonization, resulting in higher optimal crop output.

Auxin is a critical molecule that regulates most plant functions, either directly or indirectly, and indole-3-acetic acid (IAA) is the most abundant and physiologically potent phytohormone that regulates gene expression by upregulating and downregulating it [116, 117]. More than 80% of rhizospheric bacteria have been known to be capable of synthesizing and releasing auxins. IAA produced by PGPR regulates a wide range of processes in plant development and growth, including cell division, differentiation, organogenesis, tropic responses, primary root elongation, and the formation of lateral roots [118]. As a result of the increased root surface area and length mediated by bacterial IAA, plants have better access to soil nutrients. Under salinity stress circumstances, the secretion of IAA by PGPR may have a key function in managing and regulating IAA concentrations in the root system, resulting in improved plant salinity stress responses [119]. Besides, microbe-induced IAA can boost root and shoot biomass output in water-stressed situations [120].

Gibberellins (GA) are another type of phytohormone produced by rhizobacteria. Different activities in higher plants, such as seed germination, root and leaf meristem size, cell division and stem elongation, floral induction, fruiting, and the flowering process, growth of the hypocotyl and stem, are all mediated by GA [121]. However, shoot elongation is by far the most significant physiological function of GA [122], which modifies the morphology of plants.

Cytokinins are a type of growth regulators that are responsible for seed germination, production of shoots, vascular cambium sensitivity, the proliferation of root hairs, improvement of cell division and root development, interactions of plants with pathogens, and nutrient mobilization and assimilation [123, 124], but suppress root elongation and lateral root formation [125, 126]. They are especially important for the cell cycle's progression. Cytokinin, either alone or in combination with other

phytohormones like abscisic acid and auxin, can help salt-stressed plants grow faster while also improving resistance by altering the expression of genes [127]. PGPRs, such as Bradyrhizobiumjaponicum, Azospirillumbrasilense, Pseudomonas fluorescens, Arthrobactergiacomelloi, Paenibacilluspolymyxa, and Bacillus licheniformis, have been demonstrated to produce cytokinin (particularly zeatin) [69]. Cytokininproducing PGPRs act as biocontrol agents against a variety of pathogens [128].

PGPR has been proven in various investigations to be effective in both creating and regulating the amounts of ABA and gibberellic acid in plants. Gibberellins promote primary root elongation and lateral root development. Several PGPR, including Azotobacterspp, Azospirillumspp, Achromobacterxylosoxidans, Gluconobacterdiazotrophicus, Acinetobactercalcoaceticus, Bacillus spp., and Rhizobia spp., have been found to produce gibberellin [129].

The role of ABA under drought stress, for example, is well-known. Under conditions of water deficit, increased ABA levels cause stomata to shut, limiting water loss. This hormone, on the other hand, offers a variety of benefits during lateral root development [129]. Inoculation with Azospirillumbrasilense Sp245 increased ABA content in Arabidopsis, especially when grown under osmotic stress [130].

In addition to their roles in plant RSA, these two hormones are involved in plant defense mechanisms. As a result, PGPR, which produces these hormones, may affect the hormonal balance involved in plant defense, including the jasmonate and salicylic acid pathways [131].

#### **7. PGPR and abiotic stress tolerance**

As climate change conditions worsen, extreme environmental conditions that can cause significant annual losses in total crop output are now more prevalent worldwide [132, 133]. Many biotic and abiotic stresses are causing havoc on the sector, resulting in enormous plant productivity losses all around the world. Stress factors comprise nutrient shortages, heavy metal contamination, high wind, extreme temperatures, salinity, drought, illnesses, plant invasions, pests, salt, and soil erosion [69].

As a result of climate change, abiotic stresses, such as drought and high temperatures, have risen in frequency and intensity, resulting in 70% losses in major staple food crops, posing a danger to global food security [134]. Drought and high soil salinity, as well as their downstream impacts, such as osmotic, oxidative, and ionic stress, are regarded as important hindrances to long-term agriculture production [135]. Stressed plants suffer from internal metabolism disruption due to metabolic enzyme inhibition, substrate scarcity, excessive need for different chemicals, or a combo of the following. To endure unfavorable conditions, metabolic reconfiguration is required to comply with the demand for anti-stress compounds, such as suitable solutes, antioxidants, and proteins [136].

Agricultural breeding practices have tried to produce species that are more productive in unfavorable environments for ages. However, crop breeding for abiotic stress resistance has been impeded by a lack of reliable and consistent traits. Tolerance to stress is influenced by a number of genes working together. Furthermore, using agrochemicals to address biotic stresses and nutritional deficits contributes to environmental degradation, has a negative influence on the biogeochemical cycle system, and puts people at increased risk. The potential repercussions of the aforementioned stresses are significant, necessitating the development of robust, cost-effective, and environmentally acceptable methods to mitigate these stresses' harmful effects

#### *Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

on plants. As a result, there has been a spike in interest in environmentally friendly and organic agriculture techniques. Plant growth stimulants have been utilized in bio-fertilization, root revitalization, rhizoremediation, disease resistance, and other modes of microbial revival [137].

The efficient approach of PGPR can alleviate stresses that cause serious damage to crop yield, hence, the application of PGPR and/or their byproducts, which can help plants successfully resist extreme environmental circumstances, is one of the most eco-friendly ways [138]. Some PGPR genera, for instance, P. fluorescens, produce the enzymes 1-aminocyclopropane-1-carboxylate (ACC) deaminase and hydroxyacetophenone monooxygenase, which break down the ethylene precursor ACC to a-ketobutyrate and ammonia, thereby protecting plants from abiotic stressors [139]. The most destructive factors that reduce agricultural productivity are salinity and drought [140]. Furthermore, greater ethylene levels in the plant lead to premature fatuity symptoms, including leaf yellowing, abscission, and desiccation/necrosis [141]. PGPR is essential to minimize ethylene concentrations in plants, which in turn reduces stress.

During dry spells, turgor pressure and water potential have a significant impact on plant functionality. Drought stress results in substantial losses in agricultural output and the flow of nutrients, such as sulfates, nitrates, calcium, silica, and magnesium, as well as a reduction in photosynthesis activity [142]. To achieve sustainable agricultural productivity, bacterial colonies in the rhizosphere and endorhizosphere stimulate the plant to withstand drought [143]. PGPR releases osmolytes, which function in tandem with those obtained from plants to keep plants healthy and improve their growth and development, as well as withstand drought-related stress and excessive salt levels in the soil [144]. According to research findings, inoculating plants growing in dry and semi-arid areas with beneficial plant-growth-promoting rhizobacteria (PGPR), which enhances plant abiotic stress tolerance with an osmotic component, could improve drought tolerance and water utilization efficiency. PGPR-induced root development, nutrient uptake efficiency, and systemic tolerance have been proposed as biochemical changes in plants that result in increased abiotic stress tolerance (IST) [78].

#### **8. Plant biotic stress, pesticide use, and PGPR as biopesticides**

Rise in global temperature and fluctuations in precipitation as a result of climate change have resulted in unprecedented crop pests and illnesses in various parts of the world [82]. Biotic agents, such as pathogenic bacteria, viruses, fungi, nematodes, protists, weeds, insects, and arachnids, are a prevalent concern in crop production and a long-term danger to sustainable agriculture and ecosystem stability around the world [145]. These species can induce biotic stress in their hosts by interfering with normal metabolism, injuring their plant hosts, reducing plant vigor, limiting plant development, and/or inducing plant mortality. Biotic stress has an impact on co-evolution, ecosystem nutrient cycling, population dynamics, horticulture plant health, and natural habitat ecology [146]. They also result in pre- and post-harvest damage to agricultural crops [147].

According to the FAO, pests are estimated to be responsible for up to 40% of global agricultural production losses each year. Plant diseases cost the world economy more than \$220 billion per year while invading insects cost at least \$70 billion [148].

Pesticides are chemical compounds that are used to prevent or control pests. However, these are poisonous compounds that pollute soil, watercourses, and plant life. The inappropriate application and overuse of such chemicals have triggered

numerous problems (e.g., the emergence of resistance in target organisms, food contamination, and environmental pollution) [149]. Pesticide use causes morphological, physiological, biochemical, and molecular changes in plants that can have a detrimental effect on the plant's development and growth, leaving chemical residues in numerous plant tissues, as well as insect resistance to pesticides [150, 151]. Besides, pesticides cause oxidative stress in plants, hinder physiological and biochemical pathways, cause toxicity, obstruct photosynthesis, and reduce crop yield. The overgeneration of reactive oxygen species has a negative effect on non-targeted plants. Reactive oxygen species are highly reactive in nature, causing oxidative damage to lipids, nucleic acids, proteins, carbohydrates, and DNA in plants, as well as disruptions in other biochemical and physiological cell processes [152].

The rising number and intensity of pesticide consumption have presented a significant obstacle to the pests being targeted, leading them to disseminate to dynamic habitats and/or adjust to the changing settings [153]. Resistance is currently the greatest serious impediment to the effective use of pesticides. Many pest species have developed resistance to pesticides as a result of their use around the World [154].

Pesticides' impact on non-target species has been a source of debate and worry around the world for decades. Pesticides' adverse impacts on non-target arthropods have been well documented [155]. Natural insect adversaries, such as parasitoids and predators, are tragically the most vulnerable to insecticides and suffer the most harm [156]. Natural enemies that ordinarily keep small pests in check are sometimes harmed, which can lead to subsequent pest outbreaks.

Not just that, pesticide use may have a negative impact on the earthworm population. Earthworms contribute to the improvement and maintenance of soil structure by producing channels in the soil that allow for aeration and drainage. In agricultural settings, they are regarded as a key indicator of soil quality [157]. Earthworms are harmed by a wide range of agricultural practices, with indiscriminate pesticide usage being one of the most serious [158]. Yasmin and D'Souza [159] found that pesticides have a dose-dependent effect on earthworm reproduction and proliferation.

Moreover, pesticide usage has the potential to destroy biodiversity. Degraded pesticides interface with the soil as well as its inhabitants, affecting microbial diversity, biochemical processes, and enzyme activity [160]. Any change in the activity of soil microorganisms as a result of pesticide application disrupts the ecological environment, resulting in a loss of soil quality. In crops cultivated on soils excessively exposed to chemical pesticides, nutrient loss and disease incidence are widespread [161], which is unfavorable from the perspective of agricultural soil management for food and nutritional security.

Exogenous pesticide residues may also alter the efficacy of beneficial root-colonizing microbes, such as fungi, bacteria, algae, and arbuscular mycorrhiza (AM), in soil by affecting their growth, and metabolic activity, among other things [162].

Furthermore, pesticides are widely distributed when they are transported across long distances by air or water [163]. Several pesticides have a prolonged half-life (up to years) in the environment; for example, the half-life of HCH in water is determined to be 191 days [164], hence posing a threat to aquatic creatures.

The mode of pesticides' action is hazardous not just to the target organisms but also to non-target creatures, such as humans. The physicochemical parameters of the active ingredient are known to influence pesticide diffusion into plant tissue. As a result, pesticides with a systemic effect are absorbed by the roots or leaves and transported throughout the plant, as a result, they pose a major health risk to anyone who consumes them [165]. Pesticides' negative impacts on human health

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

have begun to emerge as a result of their toxicity, longevity in the environment, and tendency to penetrate the food chain. Based on the side effects, chemical pesticides employed in crop protection to limit the damage caused by pathogens and pests in agricultural areas pose significant long-term risks and challenges to life forms. Pesticides can penetrate the human body through immediate exposure to chemicals, contaminated water, or polluted air, as well as through food, particularly fruits and vegetables. Pesticide exposure can cause both acute and chronic disorders. Humans develop chronic sickness after being exposed to sub-lethal levels of pesticides for extended periods of time [166]. They are believed to stimulate cancer [167] and fetal malformations [168], and they are nonbiodegradable [169]. Encountering pesticides with genetic makeup, resulting in DNA damage and chromosomal abnormalities, is one of the primary pathways that lead to chronic disorders, such as cancer [170]. Pesticides can also cause oxidative stress by modifying the amounts of antioxidant enzymes, including glutathione reductase, superoxide dismutase, and catalase, which increase reactive oxygen species (ROS) [171]. Pesticide-induced oxidative stress has been linked to a number of health concerns, including Parkinson's disease and glucose homeostasis disruption [170].

Given the pervasive harmful effects of pesticides on plants, soil, the environment, and human health, an environmentally friendly replacement is required, making PGPR a viable option.

#### **8.1 Biopesticides/biocontrol agents using PGPR**

Biocontrol agents are bacteria that suppress the occurrence or severity of plant diseases, whereas antagonists are bacteria that have antagonistic behavior toward a pathogen. PGPR can be used as a biocontrol agent (**Figure 3**) to protect plants from pathogens, such as viruses, bacteria, insects, and fungi [173].

When compared to chemical pesticides, PGPR has unique benefits, including being harmless to mankind and nature, dissolving more quickly in soil, and having a lesser possibility of pathogen resistance development [174]. Because plants, unlike animals, are unable to use avoidance and escape as stress-relieving strategies, their

**Figure 3.** *PGPR as biocontrol agent [172].*

#### *Revisiting Plant Biostimulants*

existence has been marked by the establishment of extraordinarily favorable partnerships with their more mobile partners, microbes. PGPR and its interactions with plants are economically harnessed [175], and they hold considerable promise for longterm agricultural sustainability. Plants that have been inoculated by immersing their roots or seeds in PGPR cultures overnight have been shown to be extremely resistant to many forms of biotic stress [176].

#### *8.1.1 Antibiotic synthesis*

Antibiotic synthesis is one of the most robust and well-studied biocontrol mechanisms of PGPR against phytopathogens during the last two decades [177].  The Bacillus genus and Rhizobacteria are the most significant for antibiotic synthesis [178]. Antibacterial and antifungal antibiotics are produced by Bacillus amyloliquefaciens and B. subtilis, including subtilin, bacilysin, and emicobacillin [179].

#### *8.1.2 Induced systemic resistance*

Induced systemic resistance (ISR) is a physiological condition of increased defensive capacity triggered by a specific environmental stimulation. Conrath et al. [180] define ISR as "an enhanced defensive ability of plants in response to specific pathogens stimulated by beneficial microorganisms present in the rhizosphere," a scenario wherein the interaction of certain microorganisms with roots results in plant tolerance to pathogenic bacteria, fungi, and viruses. ISR can also be induced by certain environmental cues that cause upregulation of plants' innate defenses in response to the biotic assault, allowing plants to respond faster and stronger to subsequent pathogen attacks [181]. Following the pathogenic invasion, signals are produced, and a defense mechanism is activated via the vascular system. Among the defense mechanisms produced by ISR in plants are cell wall reinforcement [182], production of secondary metabolites, and accumulation of defense-related enzymes, such as chitinases, glucanases, peroxidase, phenylalanine ammonia-lyase, and polyphenol oxidase, lipoxygenase, SOD, CAT, and APX along with some proteinase inhibitors [183].

ISR is not unique to a particular pathogen but can benefit a plant by evading a variety of diseases. Various plants develop systemic resistance to a wide range of plant diseases and a variety of environmental stresses when primed with PGPR [184]. ISR is among the pathways through which PGPR might minimize the onset of various plant diseases by modifying the physical and biochemical attributes of host plants and thereby boosting plant growth [185]. After applying plant-growth-promoting rhizobacteria, diseases of fungal, bacterial, and viral origin, as well as damage caused by insects and nematodes, can be decreased [186].

Non-pathogenic microorganisms promote ISR, which starts in the roots and extends to the shoots [187]. ISR stimulates plant defense mechanisms and shields unexposed regions of plants against future pathogenic attacks by microbes and insects. The signaling of ethylene and jasmonic acid in the plant is involved in induced systemic resistance, and these hormones increase the host plant's defense responses against a range of plant diseases [188]. Lipopolysaccharides (LPS), siderophores, homoserine lactones, 2, 4-diacetylphloroglucinol, cyclic lipopeptides, and volatiles like acetoin and 2, 3-butanediol are only a few of the bacterial components that cause induced systemic resistance [189].

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

#### *8.1.3 Production of protective enzymes*

Plant-growth-promoting rhizobacteria use another mechanism to promote growth—enzymatic activity, producing compounds that inhibit phytopathogenic agents [190]. Rhizobacterial strains that promote plant growth can secrete enzymes, including ACC-deaminase, phosphatases, chitinases, 1,3-glucanase, proteases, dehydrogenases, and lipases, among others [94, 191]. They excrete cell wall hydrolases, which are used to break down cell walls, neutralize infections, assault pathogens, and cause hyperparasitic activity [192]. Plant-growth-promoting rhizobacteria suppress pathogenic fungi, such as *Phytophthora sp, Botrytis cinerea, Fusarium oxysporum, Sclerotium rolfsii*, *Pythium ultimum*, and *Rhizoctonia solani* by the activation of such enzymes [193, 194], hence defending the plant against various biotic and abiotic stresses. Because 1,4-N-acetylglucosamine and chitin make up the majority of fungal cell wall constituents, bacteria that generate 1,3-glucanase and chitinase restrict their proliferation. Inoculation of plants with arbuscular mycorrhiza has also been shown to increase plant growth. *Trichoderma* strains have been employed as biological control agents and plant growth boosters in the past [195].

#### *8.1.4 Production of volatile organic compounds (VOCs)*

In recent years, microbial volatile organic compounds (mVOC) have been shown to play an important role in microorganism–plant interactions [196–198]. VOCs are produced by a wide range of soil microorganisms. Bacillus bacteria are the most common microbes that produce antimicrobial MVOCs. Bacterial volatiles have a key function in encouraging plant growth by regulating phytohormone synthesis and metabolism.

They can also promote plant health by acting as antibacterial, nematicidal, oomyceticidal, and antifungal agents, as well as eliciting plant immunity via the salicylic acid (SA) and jasmonic acid (JA) pathways [199]. These molecules have the potential to increase plant growth and development and induce systemic resistance (ISR) against pathogenic organisms, resulting in improved agricultural well-being [200]. Through the SA-signaling pathway, acetoin from the bacteria B. subtilis produces systemic resistance in *A. thaliana* against *P. syringae* [201].

Depending on the species, the quantity and composition of VOCs varies [202]. 2, 3-Butanediol is a volatile organic compound (VOC) generated by a variety of microorganisms that, among other things, can activate plant resistance against pathogens. This mVOC generated by *B. subtilis* and *B. amyloliquefaciens* is capable of generating a systemic resistance in A. thaliana mediated by the ethylene (ET)-signaling pathway against *Erwinia carotovora* subsp. *carotovora* [196]. The same MVOC from *Enterobacter aerogenes* was engaged in the establishment of plant tolerance against *Setosphaeria turcica,* a fungus that causes Northern corn leaf blight [203].

#### *8.1.5 Hydrogen cyanide (HCN) production*

The antagonistic activity of PGPR also results in the production of volatile compounds. HCN, a well-studied biocontrol agent, commonly known as prussic acid, is a broad-spectrum volatile secondary metabolite generated by numerous rhizobacteria and is crucial for the biological control of several infectious microorganisms in the soil. Most metalloenzymes are inhibited by their cyanide ion, particularly coppercontaining cytochrome c oxidases [204]. HCN-producing Pseudomonas strains are

employed in the biological control of tomato bacterial canker [205]. For instance, the inhibition of Macrophomina phaseolina and Meloidogyne javanica caused sunflower charcoal rot and tomato root-knot diseases and has been related to bacterial strains secreting HCN [206]. The inhibitory activity process starts in the mitochondria, where HCN inhibits electron transport, reducing energy supply to the cell and finally causing pathogenic organisms to die.

#### *8.1.6 Aminocyclopropane-1-carboxylate (ACC) deaminase production*

Plants generate a lot of "stress ethylene" (ET) after the onset of a disease or stress. Much of the growth inhibition that happens as a result of environmental stress is due to the plant's response to elevated levels of stress ethylene, which aggravates the stressor's response. Likewise, ethylene production inhibitors can considerably reduce the intensity of various environmental stressors. The production of defense enzymes, including 1-aminocyclopropane-1-carboxylate (ACC) deaminase, has also been linked to PGPM's ability to protect against biotic stress [207]. Numerous results suggest that seed inoculation with bacterial endophytes increases plant defense. This is because bacteria produce the enzyme 1-aminocyclopropane-1-carboxylate (ACC), which can cleave ET into ketobutyrate and ammonia, lowering the presence of this enzyme linked to plant stress and physiological impairment [208]. As a result, if ACC deaminase-containing bacteria can reduce plant ethylene levels, treating plants with these organisms may give some defense against the stress inhibitory effects. The synthesis of ACC-deaminase by *Paenibacillus lentimorbus* B-30488 (B-30488) is assumed to be the pathway whereby *P. lentimorbus* B-30488 (B-30488) negates Scelerotium rolfsii in tomato [207]. Hence, the usage of PGPR is appropriate for reducing the environmental stress that crop plants face.

### **9. Conclusion**

To meet the ever-increasing nutritional demand of the rapidly increasing world population, chemical fertilizers must be employed. However, unintended and excessive use has a variety of negative repercussions on the natural environment resulting in soil degradation, global warming, and climate change, necessitating the search for environmentally sound alternatives. PGPR, in this regard, is a realistic choice for agricultural production that does not deplete natural resources. Plants and microbial communities in the soil have evolved a variety of biotic connections, ranging from commensalism to mutualism. Plant-PGPR collaboration is an important aspect of this web of interactions, promoting the growth and health of a variety of plants. PGPR has recently received a lot of attention for its potential to replace agrochemicals for plant growth and yield through a variety of processes, including decomposition of organic matter, recycling of essential elements, formation of soil structure, production of numerous plant growth regulators, fixation of atmospheric nitrogen, degradation of organic pollutants, stimulation of root growth, solubilization of phosphorus, production of siderophore, and solubilization of mineral nutrients, all of which are important for soil and plant health. Furthermore, they are cost-efficient and environmentally sustainable and assure that nutrients from natural sources are always accessible. Besides, bacterial colonies in the rhizosphere have a considerable impact on phytopathogenic microorganism reduction, in addition to boosting plant growth through active processes, hence the use of phytomicrobiome representatives

*Plant-Bacterial Symbiosis: An Ecologically Sustainable Agriculture Production Alternative… DOI: http://dx.doi.org/10.5772/intechopen.104838*

in farming production as long-term disease prevention and nutrient supplement strategy could also help to mitigate the detrimental effects of pesticide use.

As a nutshell, in the face of global climate change, PGPR could be a more environmentally friendly option than chemical fertilizers.


**5. Discussion**

Metallica's success is based the power duo of Ulrich and Hetfield. Their common ground is the strong desire for control, the struggle against the enemies, the need for constant progress and love for music. These factors form the Metallica spirit, stemming from Ulrich and Hetfield's internal conflicts. In addition to enabling Metallica to succeed, these four factors have kept the band alive in the midst of quarrels. The most important Metallica's success factor seems to be the desire for control. Ulrich and Hetfield hate the idea that authorities or gurus would steer the Metallica ship. In practice, Ulrich and Hetfield have avoided conflicts with other stakeholders by strong control. The need for controlling springs from different sources for Ulrich and Hetfield. Ulrich has little or no tolerance for uncertainty and obscurity, the latter has a fear of loss regarding the personal freedom and running out of creative force. Therefore, the will to fight that arose from negative emotions has defined a lot the success of Metallica. On the other hand, there has been passionate love for music.

broke up in the early 2000s. Bad emotions started to accrue since Burton died year 1986. This extremely destructive conflict was handled with avoiding it for 15 years. Furthermore, several new conflicts emerged from this conflict. Conflicts were hidden by humor and numbed with alcohol and drugs, until all the feeling bad came out at once. In consequence, relationship and status conflicts exploded. Even task and process conflicts were getting dysfunctional, the fact

Conflicts as Springboard for Metallica's Success http://dx.doi.org/10.5772/intechopen.71579 147

As the fear, anger and love for music helped in achieving the band the status of world's greatest heavy rock band, the maturing as people and a more positive outlook on life helped to keep the band alive and continue to make still relevant music. The newest album, Hardwired …to Self-destruct in 2016, is a good example of a more harmonic Metallica. There are conflicts within the band, and with external stakeholders, but they are less frequent than before and they are handled better. The worst rebelliousness is over, but new experiments and striving for one's freedom have continued. A good example of the first is the very controversial Lulu album in 2011, and of latter the same year established own record company, with which

The ways of handling conflicts have changed during the band's career. **Figure 5** shows Metallica's progression at roughly level album by album, and the prevalent conflict handling method or mix of them. Figure show also the biggest spots of musical discontinuity between

If you want to lift one conflict handling way above others in Metallica, it is competing. Especially at the beginning, the members concentrated on competing against each other. The competition provoked the personal creativity and at the same time Metallica advanced musically.

**Figure 5.** Conflict handling methods and innovation discontinuity during the Metallica life cycle.

that we can hear in the mediocre albums Load, Reload and St. Anger.

Metallica has full control of its actions.

albums.

**Table 1** shows Ulrich's and Hetfield's personalities based on available information. From the factors that provoke innovativeness, Ulrich's personality is emphasized by openness, while Hetfield's strengths are conscience and lack of agreeability. Furthermore, Ulrich has concentrated more on big picture while Hetfield has focused on the details, and Hetfield is great on stage while Ulrich dominates off-stage. Although the difference has complemented Ulrich and Hetfield as human beings, and have created Metallica's innovation power, differences have also caused lots of destructive conflicts between them. One of the reasons for this is their very different backgrounds. Their families were far apart geographically, culturally and economically. It should also be noted that although extroversion and neuroticism are not the most important factors for innovativeness, personal differences in these factors have also created conflicts. For example, with regard to extroversion, Hetfield has remained silent and shy, and often in Ulrich's shadow who is a talkative, which was bad for Hetfield's self-esteem especially in the early days of Metallica. Ulrich and Hetfield's most dramatic personality features have leveled off since the beginning of Metallica. Especially Hetfield, who has grown considerably as human being and got rid of many destructive intrapersonal conflicts.

The good handling of task and process conflicts helped the band create great music up till 1991 the Black album, yielding functional outcomes. Under the surface, however, bad emotions smoldered and escalated for the first time to a longer dysfunctional state as the band nearly

**Table 1.** Personalities of Ulrich and Hetfield.

broke up in the early 2000s. Bad emotions started to accrue since Burton died year 1986. This extremely destructive conflict was handled with avoiding it for 15 years. Furthermore, several new conflicts emerged from this conflict. Conflicts were hidden by humor and numbed with alcohol and drugs, until all the feeling bad came out at once. In consequence, relationship and status conflicts exploded. Even task and process conflicts were getting dysfunctional, the fact that we can hear in the mediocre albums Load, Reload and St. Anger.

**5. Discussion**

146 Organizational Conflict

Metallica's success is based the power duo of Ulrich and Hetfield. Their common ground is the strong desire for control, the struggle against the enemies, the need for constant progress and love for music. These factors form the Metallica spirit, stemming from Ulrich and Hetfield's internal conflicts. In addition to enabling Metallica to succeed, these four factors have kept the band alive in the midst of quarrels. The most important Metallica's success factor seems to be the desire for control. Ulrich and Hetfield hate the idea that authorities or gurus would steer the Metallica ship. In practice, Ulrich and Hetfield have avoided conflicts with other stakeholders by strong control. The need for controlling springs from different sources for Ulrich and Hetfield. Ulrich has little or no tolerance for uncertainty and obscurity, the latter has a fear of loss regarding the personal freedom and running out of creative force. Therefore, the will to fight that arose from negative emotions has defined a lot the success of

**Table 1** shows Ulrich's and Hetfield's personalities based on available information. From the factors that provoke innovativeness, Ulrich's personality is emphasized by openness, while Hetfield's strengths are conscience and lack of agreeability. Furthermore, Ulrich has concentrated more on big picture while Hetfield has focused on the details, and Hetfield is great on stage while Ulrich dominates off-stage. Although the difference has complemented Ulrich and Hetfield as human beings, and have created Metallica's innovation power, differences have also caused lots of destructive conflicts between them. One of the reasons for this is their very different backgrounds. Their families were far apart geographically, culturally and economically. It should also be noted that although extroversion and neuroticism are not the most important factors for innovativeness, personal differences in these factors have also created conflicts. For example, with regard to extroversion, Hetfield has remained silent and shy, and often in Ulrich's shadow who is a talkative, which was bad for Hetfield's self-esteem especially in the early days of Metallica. Ulrich and Hetfield's most dramatic personality features have leveled off since the beginning of Metallica. Especially Hetfield, who has grown

considerably as human being and got rid of many destructive intrapersonal conflicts.

**Personality factors in Big five model Lars Ulrich James Hetfield**

**Table 1.** Personalities of Ulrich and Hetfield.

*Openness to experience* more inventive/curious more consistent/cautious *Conscientiousness* more easy-going/careless more efficient/organized *Agreeableness* more friendly/compassionate more challenging/detached *Extroversion* more outgoing/energetic more solitary/reserved *Neuroticism* more secure/confident more sensitive/nervous

The good handling of task and process conflicts helped the band create great music up till 1991 the Black album, yielding functional outcomes. Under the surface, however, bad emotions smoldered and escalated for the first time to a longer dysfunctional state as the band nearly

Metallica. On the other hand, there has been passionate love for music.

As the fear, anger and love for music helped in achieving the band the status of world's greatest heavy rock band, the maturing as people and a more positive outlook on life helped to keep the band alive and continue to make still relevant music. The newest album, Hardwired …to Self-destruct in 2016, is a good example of a more harmonic Metallica. There are conflicts within the band, and with external stakeholders, but they are less frequent than before and they are handled better. The worst rebelliousness is over, but new experiments and striving for one's freedom have continued. A good example of the first is the very controversial Lulu album in 2011, and of latter the same year established own record company, with which Metallica has full control of its actions.

The ways of handling conflicts have changed during the band's career. **Figure 5** shows Metallica's progression at roughly level album by album, and the prevalent conflict handling method or mix of them. Figure show also the biggest spots of musical discontinuity between albums.

If you want to lift one conflict handling way above others in Metallica, it is competing. Especially at the beginning, the members concentrated on competing against each other. The competition provoked the personal creativity and at the same time Metallica advanced musically.

**Figure 5.** Conflict handling methods and innovation discontinuity during the Metallica life cycle.

The main thing was to win a conflict without caring for the other parties. In the external competing, the band overcame the hindrances that were in its way. In the competing method, one concentrates on its or his own problems. Metallica and its members were exceptionally devoted to its cause and not caring about the critique. However, as a conflict handling method, competing has its risks in the long term, as shown in the Metallica crises.

Metallica's music in the 1980s, and then again Hardwired… to Self-destruct is a cross-section of the bands whole career. The harmony of the band and its trait for compromises can well be

Conflicts as Springboard for Metallica's Success http://dx.doi.org/10.5772/intechopen.71579 149

Metallica has also utilized successfully conflict stimulation techniques such as communication (e.g. Ulrich's and Hetfield's provocation), bringing in outsiders (e.g. Burton as a new skilled artist) and even devil's advocates (Rock and Towle). Conflict stimulation has been balancing with the double-edged sword. As a summary, Metallica has handled and stimulated conflicts exceptionally well during its career. Literature says that competition does not yield as good results as does collaboration. Metallica's skill has been to create an optimal mixture of competition and collaboration in the critical phases of its career. **Figure 6** summarizes the essential things at Metallica case from the point of conflict management. Left side of figure

Although the record sales are nowadays not nearly as good as it used to, the fan base has been growing in the 2000s. In the 2010s, however, there has been a decline, and it may well be that the band has been unprofitable for the first time since 1980s. On the other hand the 2016 album Hardwired… to Self-Destruct seen to bring some help to this. A more reconciling attitude in conflict situations seems to fit the matured band, when it balances on the border of the mature and decline stages of its life span. It is interesting, that competing has risen as a conflict handling method to the surface, from time to time. If history keeps repeating itself, Metallica has the next battle ahead and it involves strong competition. Maybe it is competition

seen in its music. The band has started thinking how to please others.

describes the functional conflicts and right side the dysfunctional conflicts.

toward the decline.

**Figure 6.** Summary of conflicts and their handling at Metallica case.

Alongside the competing, the collaborating strengthened as the conflict handling means during the 1983–1986. Metallica's "Metal-time", the delayed composing practice is good example of collaborating. After this, the unexpected death of Burton and the egos had been growing since the success of the Master of Puppets album. During this period, the competing returned to the main conflict management method. Collaborating strengthened again when making the Black album. However, with the great success of this album the vanity really started get to them, and the most confused time of the band started. This can be heard in the albums Load, Reload and St. Anger. At this period Ulrich and Hetfield were first time in different camps. They compete with each other who is the leader in Metallica. So Metallica itself became the cause of the conflict, when before Metallica spirit had been an invisible power that bound the band members together. Hammett has also been pivotal role as he has acted as a peacemaker and diplomat between Ulrich and Hetfield. Burton and Burnstein have been in same role. In conflict situations, they usually used the unselfish accommodating method.

Making the album St. Anger the band had a crisis that was the biggest in its career that only with the help of therapy it was able to solve. Also, the role of cameras, that filmed Some Kind of Monster documentary, cannot be diminished. The cameras prohibited the band members from doing in conflict situations as they used to do: joke and lie. After the therapy, the performance coach Towle told that the band is no more afraid of conflicts, but holds the tension caused by them as an asset. In conflict situations one is no more in one's shell, but opens up to others. They trust that something good will come out of it. You could say that the band has started anew after the crisis, as more mature. Members of the band were able to appreciate to each other. The corrective maneuver in attitude was very important and brought the band lots of more years to live. After the crisis, the collaborating, compromising, and even accommodating were used as conflict handling methods. An example of the last one is the band showing their esteem to the old band members and partners by inviting them to the band's 30 year party and paying for it all. Metallica is at its most harmonic state ever, and members enjoy work together. Metallica does not make music that is opening new paths anymore, but it has sustained the status of world's biggest heavy rock band.

The methods which Metallica has handled conflict have changed with the years, as have the musical styles. They have not gone with reinventing the wheel if not counting the albums Reload, Death Magnetic and Hardwired… to Self-destruct. The band tells its music has progressed its natural path. When compared to other bands the musical style changes have mostly been so big, that we can say radical changes instead of incremental improvements. The most radical change happened before Black album, when the band created the biggest discontinuity compared to its earlier music. The Death Magnetic album is a return to the Metallica's music in the 1980s, and then again Hardwired… to Self-destruct is a cross-section of the bands whole career. The harmony of the band and its trait for compromises can well be seen in its music. The band has started thinking how to please others.

The main thing was to win a conflict without caring for the other parties. In the external competing, the band overcame the hindrances that were in its way. In the competing method, one concentrates on its or his own problems. Metallica and its members were exceptionally devoted to its cause and not caring about the critique. However, as a conflict handling

Alongside the competing, the collaborating strengthened as the conflict handling means during the 1983–1986. Metallica's "Metal-time", the delayed composing practice is good example of collaborating. After this, the unexpected death of Burton and the egos had been growing since the success of the Master of Puppets album. During this period, the competing returned to the main conflict management method. Collaborating strengthened again when making the Black album. However, with the great success of this album the vanity really started get to them, and the most confused time of the band started. This can be heard in the albums Load, Reload and St. Anger. At this period Ulrich and Hetfield were first time in different camps. They compete with each other who is the leader in Metallica. So Metallica itself became the cause of the conflict, when before Metallica spirit had been an invisible power that bound the band members together. Hammett has also been pivotal role as he has acted as a peacemaker and diplomat between Ulrich and Hetfield. Burton and Burnstein have been in same role. In

Making the album St. Anger the band had a crisis that was the biggest in its career that only with the help of therapy it was able to solve. Also, the role of cameras, that filmed Some Kind of Monster documentary, cannot be diminished. The cameras prohibited the band members from doing in conflict situations as they used to do: joke and lie. After the therapy, the performance coach Towle told that the band is no more afraid of conflicts, but holds the tension caused by them as an asset. In conflict situations one is no more in one's shell, but opens up to others. They trust that something good will come out of it. You could say that the band has started anew after the crisis, as more mature. Members of the band were able to appreciate to each other. The corrective maneuver in attitude was very important and brought the band lots of more years to live. After the crisis, the collaborating, compromising, and even accommodating were used as conflict handling methods. An example of the last one is the band showing their esteem to the old band members and partners by inviting them to the band's 30 year party and paying for it all. Metallica is at its most harmonic state ever, and members enjoy work together. Metallica does not make music that is opening new paths anymore, but it has sustained the status of world's biggest

The methods which Metallica has handled conflict have changed with the years, as have the musical styles. They have not gone with reinventing the wheel if not counting the albums Reload, Death Magnetic and Hardwired… to Self-destruct. The band tells its music has progressed its natural path. When compared to other bands the musical style changes have mostly been so big, that we can say radical changes instead of incremental improvements. The most radical change happened before Black album, when the band created the biggest discontinuity compared to its earlier music. The Death Magnetic album is a return to the

method, competing has its risks in the long term, as shown in the Metallica crises.

conflict situations, they usually used the unselfish accommodating method.

heavy rock band.

148 Organizational Conflict

Metallica has also utilized successfully conflict stimulation techniques such as communication (e.g. Ulrich's and Hetfield's provocation), bringing in outsiders (e.g. Burton as a new skilled artist) and even devil's advocates (Rock and Towle). Conflict stimulation has been balancing with the double-edged sword. As a summary, Metallica has handled and stimulated conflicts exceptionally well during its career. Literature says that competition does not yield as good results as does collaboration. Metallica's skill has been to create an optimal mixture of competition and collaboration in the critical phases of its career. **Figure 6** summarizes the essential things at Metallica case from the point of conflict management. Left side of figure describes the functional conflicts and right side the dysfunctional conflicts.

Although the record sales are nowadays not nearly as good as it used to, the fan base has been growing in the 2000s. In the 2010s, however, there has been a decline, and it may well be that the band has been unprofitable for the first time since 1980s. On the other hand the 2016 album Hardwired… to Self-Destruct seen to bring some help to this. A more reconciling attitude in conflict situations seems to fit the matured band, when it balances on the border of the mature and decline stages of its life span. It is interesting, that competing has risen as a conflict handling method to the surface, from time to time. If history keeps repeating itself, Metallica has the next battle ahead and it involves strong competition. Maybe it is competition toward the decline.

**Figure 6.** Summary of conflicts and their handling at Metallica case.