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Ecology of groundnut

The main range of peanut cultivation is between 35o S and 40o N, but it extends to 45oN in Central Asia and North America. It adapts to wide range of environments. It is normally grown commercially below 1250 m, although many varieties could be found at much higher elevations. It is a day neutral plant and thus little affected by day length. However, plant growth is adversely affected by low light intensity. Bunchy types are generally more severely affected by climatic variation than runner types. Temperature between 25 to 30oC is optimum for plant development. Once established, peanut is drought resistant, and to some extent it also tolerates flooding. A rainfall of 500 to 1000 mm will allow commercial production, although crop can be produced on as little as 300 to 400 mm of rainfall. Once pods are mature, rainfall will adversely affect the crop as some cultivars have a very brief dormancy and germinate under suitable condition.