Efficiency of microsatellite markers in assisted selection for resistance to soybean cyst nematode (race 3)

Abstract

Four microsatellite sequences were tested in soybean DNA from cultivars and segregating genotypes. Three of them were close to the resistance locus rhg1 on molecular linkage group G (Satt309, Sat_168, Sat_163) and one was close to Rhg4 locus on group A2 (Sat_162). Progenies previously classified as cyst nematode (SCN) resistant and others with unknown reaction were tested, using the resistant cultivars Liderança, and Renasscença and the susceptibles 'Cristalina' and 'OCEPAR-4' as control. The best primer for resistance to SCN was Sat_162. Twenty segregant progenies tested with Sat_162 presented a 150 bp band for homozygous resistant genotypes and 200 bp for susceptible ones, and both for the heterozigous genotypes. Previous studies have shown that this microsatellite marker is efficient to select genotypes carrying Peking-derivative resistance. 'Peking' takes part in the in the genealogy of all segregant progenies evaluated in this study. Thus, the obtained results showed that Sat_162 distinguished resistant and susceptible soybean genotypes to SCN, race 3.

Progênies superiores de soja resistentes ao tipo 3 do nematóide de cisto da soja

“…Resultados similares foram obtidos por Arantes et al (1998), Campos et al (2003) e Mauro et al (2004) em trabalhos realizados com soja, utilizando-se da mesma técnica de avaliação do patógeno e objetivo semelhante, tendo confirmada sua eficiência. Tabela 3.…”

Multivariate statistics applied to the reaction of common bean plants to parasitism by Meloidogyne javanica

“…Thus, the most practical, inexpensive and efficient control measure is the use of resistant and/or tolerant cultivars (Mauro et al, 2004). In this context, one can cite the huge importance of family farmers, who have cultivated their own genotypes (landrace genotypes) for many years by saving seeds for the next crop and repeating this process in a continuous cycle.…”