Microsatellite molecular markers in the cultivar identification of Brazilian soybean for human consumption.

The objective of this research was to exploit the variability of 69 microsatellite marker loci in 18 soybean varieties (group I) to select 10 loci for routine cultivar identification. The selected loci were used to evaluate 32 varieties (group II). In group I an average of 3.36 alleles per locus was observed of a total of 232 alleles and an average of 5.1 alleles per locus for the 32 varieties evaluated in group II. The mean distance values were 0.67 and 0.82 for group I and group II, respectively. The 10 loci selected and evaluated in group II were the most effective to discriminate the genotypes and, therefore, recommended for the characterization of Brazilian soybean cultivars for human nutrition. Key-words: Glycine max, SSR, cultivar protection, germplasm. industrialized countries have implanted protection systems of improved varieties. Brazil has a national legislation that regularizes the protection system of the country’s lines and cultivars. The Law of Cultivar Protection requires that cultivars submitted to trademark registration and protection must present traits of distinction, homogeneity and stability (DHS). To discriminate genotypes, morphologic and biochemical traits must be evaluated. The use of this kind of trait data as identification criteria hinders the registration of new cultivars with identical traits to others registered before. Since the number of new cultivars is on the rise whereas the number of differentiating traits is constant, the clear distinction of 1 Departamento de Genetica, Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Avenida Padua Dias, 11, C.P. 9, 13.418-000, Piracicaba, SP, Brasil 2 Naturale, Rua Dr. Jaime Ribeiro Luz, 971, Bairro Santa Monica, 34.408-188, Uberlândia, MG, Brasil 3 Instituto Agronomico, Avenida Barao de Itapura, 1481, C.P. 28, 13.012-970, Campinas, SP, Brasil. E-mail: mizucchi@iac.sp.gov.br 4 Departamento de Genetica e Evolucao, Instituto de Biologia, Universidade Estadual de Campinas, Cidade Universitaria Zeferino Vaz, Barao Geraldo, 13.083-970, Campinas, SP, Brasil