Descrição do processo de sementes genéticas de soja (Glycine max (L.) Merrill)

Abstract

Brazil is the second producer of soybean seeds, the crop with the largest number of varieties protected, which must be registered and submitted to the test of distinction, homogeneity and stability. Morphological descriptors are not always effective, because the plant phenotype suffers the effect of the environment. Molecular markers of proteins and DNA make it possible to evaluate the genetic purity of seeds in an incisive way, since the alleles do not suffer environmental influence. In this way, a research bibliography was done on the subject to discuss the production, multiplication and purification of soybean genetic seeds. Genetic purification steps can be performed per plot for individual selection of plants, progeny lines, progeny blocks, and by mass selection. The causes that can affect the genetic base of cultivars are: mechanical mixtures; Natural crosses; Mutations; Changes in gene frequency, caused by samplings, genetic oscillation, by natural selection, by the selection of the breeder; Loss of heterozygosity. High-quality seeds enable optimized purification processes. The production of genetic seed is of prime importance for the launching of new cultivars. Genetic improvement programs, together with those responsible for purification, are responsible for the launching of new cultivars on the market from a lineage that excelled in the VCU trials. The decontamination process allows the removal of undesirable plants that can pollinate the soybean or that produce mechanical contamination at harvest. In view of the above, quality seeds become paramount, and the productive potentials sought by the producers will only be reached if the seed demonstrates its characteristic genetic potential. Certified seed may provide a producer safety with regard to genetic, physical, physiological and phytosanitary quality. The processes of purification and maintenance of genetic purity are primordial for the producers to acquire the seeds according to the desired homogeneity and stability characteristics through successive generations, from phenotypic and genotypic evaluations, from the morphological descriptors.