History of plant breeding and a cultivated crop species that has evolved from wild populations due to selective pressures from traditional farmers is called a landrace. Landraces, which can be the result of natural forces or domestication, are plants or animals that are ideally suited to a particular region or environment. An example are the landraces of rice, "Oryza sativa" subspecies "indica", which was developed in South Asia, and "Oryza sativa" subspecies "japonica", which was developed in China. For more on the mechanisms of domestication, see Hybrid (biology). Humans have traded useful plants from distant lands for centuries, and plant hunters have been sent
Scirpophaga nivella orange anal tuft, sometimes brownish in the female. The larvae are off white with a reddish dorsal line. Major feeding plant is sugarcane, besides "Oryza sativa", "Scirpus", "Cyperus", "Eleocharis" (including "Eleocharis dulcis") and "Calidum articulatum" are also susceptible as feeding plants of the moth. Caterpillars bore into midrib, by leaving red markings and small holes on the leaves. Then it bore in the upper portion of stem, causing "dead heart" symptoms. Gradually, side branches start growing from a lower node, giving a characteristic "bunchy top" appearance to the plant. Most effective method is using biological predators and parasitoids. It is