Introduction to crop variety improvement
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Introduction to crop variety improvement
The development of improved, fertilizer-responsive high-yielding varieties of wheat and rice during the early 1960s and their widespread adoptions by farmers, first in Asia and then in Latin America, marked the beginning of what is known as the Green Revolution. Much has been written about this technological breakthrough and its impact-both positive and negative-in the years since its effects were first felt in farmers fields across India, Mexico, and Philippines. Since then, improving crop germplasm and the development of new varieties through well focused crop breeding programmers have been extended too many other food and feed crops in developing countries.
It is reasonable to assume that plant breeding, howsoever primitive, began when man first chose certain plants for cultivation; this began 10,000 years ago when main is believed to have started agriculture. The processes of bringing a wild species under human management are referred to as domestication. During the long period of prehistoric and historic cultivation, natural selection has definitely acted on the domesticated species. It is likely that man also exerted some selection wither knowingly or unknowingly. Movement of man from one are to another brought about the movement of his cultivated plant species. The introduction into an area of new plant species or varieties from other parts of the world is an integral part of plant breeding today.
Important types of crop variety:
Crops: Crops are plants cultivated by humans for food, fodder and other materials. The important types of crops are: • Cereal crops: Wheat, rice, maize, barley, sorghum, minor millets. They are rich source of carbohydrates that meet the energy requirement of body. • Pluses: Gram, pea, black gram, green gram, pigeon pea, lentil. • Oil seed crops: Groundnut, mustard, linseed, sunflower, sesame,