ABSTRACT
Applied genetics or plant breeding has been one of the most effective sciences for increasing productivity of crop plants. Improved varieties, developed by application of genetic principles, provide increases in total yield of food, feed or fiber. The first step in a plant breeding program is evaluation of already existing materials. These include such indigenous materials as local varieties, farmers' seed lots and natural stands, as well as varieties and collections from other areas of the world. A collecting and testing program to identify the best seed lots for each region and the subsequent increase and distribution of the best as varieties can have an important impact, within a short time, on food or fiber production in the country. The plant breeder in the developing country may obtain introductions from foreign sources by correspondence with other plant breeders, exchanges of collections by individuals or organizations in the respective countries, and organized collecting expeditions.
