Stem rust fungus. Different from most fungi, the rust variations have five spore stages and alternate between two hosts. Wheat is the primary host, and barberry is the alternate host. There are multiple pathotypes (including QCC and MCC) affecting barley, within "forma specialis tritici". The stem rust fungus attacks the parts of the plant that are above ground. Spores that land on green wheat plants form a pustule that invades the outer layers of the stalk. Infected plants produce fewer tillers and set fewer seed, and in cases of severe infection the plant may die. Infection can reduce what is an apparently
Soybean rust Besides, ASR pustules are raised and can be commonly found on the underside of the leaf which makes it different from the lesions caused by spot diseases. As one of ASR's most known hosts, soybean plants are susceptible at any stage in the life cycle. However, symptoms are most commonly found during or after flowering. Soybean plants infected by Asian Soybean Rust will result in declining of pod production and fill. Asian Soybean Rust (ASR) was first detected in Asia. It has been found in many countries around the world since then. For example, Australia, China, Korea, India, Japan, Nepal,