ABSTRACT
The development of new varieties of crop plants largely occurs through variation and selection. Variation, defined as the emergence of differences between individuals in a population, serves as the raw material for varietal development or plant breeding. Using important traits as the criteria, superior plants suited to particular environments, management methods or markets can then be selected. For example, if a variable population is exposed to selection in the presence of a commonly grown variety (known as a check variety), some genotypes may perform better than the check. A breeder or farmer may then be able to select a genotype with greater potential than the commonly grown variety. The superiority of an identified line is normally validated through a series of trials, which often take the form of a multi-year multi-location evaluation. Once the superiority of a new variety has been established, it is registered and released for cultivation by a competent authority. In many countries, a committee is responsible for identifying new crop varieties developed by the public sector. In India, this is the task of the Varietal Identification Committee, which usually takes decisions during an annual national workshop. Following this, the government again verifies the superiority through another committee and then issues an official notification for the release of variety for cultivation by farmers. There are typically also standard identification procedures for varieties developed by the private sector, but these differ between countries. Seeds are then produced following a defined procedure, so as to maintain the superior variety’s physical and genetic purity and to meet minimum seed standards. They are then disseminated among farmers and other stakeholders.
