Molecular Genetics — Plant Breeder’s Perspective

Abstract

Plant breeding is the art and science of changing and improving the heredity of plants to develop desired products with new genetic properties. The science of plant breeding consists of two phases, the evolutionary phase, which aims at creating or enlarging genetic variability, and the evaluation phase, which aims at selecting desirable genotypes from the variable populations. During the last four decades, major gains have been made in increasing productivity of major food crops worldwide. As an example, world rice production has more than doubled from 257 million tones in 1966 to 596 million tones in 1999. These gains in crop productivity have been achieved mainly through the application of principles of Mendelian Genetics and conventional plant breeding methods. However, to meet the growing need of ever increasing human population, the food grain production must increase by 50% in 2025. International Food Policy Research Institute (IFPRI, 1997) has estimated that maize production must increase by 80%, wheat by 60%, and rice by 40% during the next 25 years. There are no more suitable lands available for expansion of agriculture. Also, intensive agricultural systems have raised concerns about degradation of natural resources and environment deterioration. Therefore, we have to increase the food grain production from less land, less chemicals, less water, and less labor.