Mapping Resistance to Multiple Races of Heterodera glycines in Soybean PI 89772

Abstract

Breeding soybean [Glycine max (L.) Merr.] cultivars for resistance to soybean cyst nematode (SCN) [Heterodera glycines Ichinohe] is the most efficient means to control this pest. Evaluating and developing new resistance germplasm sources for soybean breeding is very important to prevent SCN from race shifts and provide durable resistance in soybean. We evaluated a newly found germplasm, soybean plant introduction (PI) 89772, which is resistant to SCN Races 1, 2, 3, 5, and moderately resistant to Race 14. The objectives were to identify molecular markers associated with SCN resistance, investigate resistant allelic relationships, and evaluate marker‐assisted selection efficiency. The F2 and F2:3 populations were produced by crossing PI 89772 with the susceptible soybean cultivar Hamilton. Thirty‐nine restriction fragment length polymorphism (RFLP) and 54 simple sequence repeat (SSR) markers found to be polymorphic were used to anchor loci conferring resistance to SCN Races 1, 2, 3, and 5. Two to three loci were found to give resistance to each SCN race. We found that resistance loci for different races could be anchored within the same region on linkage group (LG) G. A region on LG B1 was also shared by loci providing resistance to SCN Races 1, 2, and 5. Our results indicated that no single locus could provide complete resistance to any one SCN race. The major loci combinations provided high levels of resistance. We conclude that these markers could be highly useful in marker‐assisted selection.

Parâmetros genéticos da resistência da soja ao nematóide de cisto Raça 1

“…Também foi verificado que as médias das linhagens avaliadas não conseguiram alcançar a média do genitor resistente (0,6). A variação transgressiva também foi observada em trabalho realizado por YUE et al (2001a) em famílias F 2:3 , derivadas do cruzamento entre a PI89772 (genitor resistente) e a cultivar Hamilton (genitor suscetível), inoculadas e avaliadas com a raça 5 do NCS.…”

Development of SNP markers and haplotype analysis of the candidate gene for rhg1, which confers resistance to soybean cyst nematode in soybean

“…rhg1 was identified by classical genetic analysis as a recessive gene (Caldwell et al 1960;Arelli et al 1992) which seems to be common to major SCN resistance sources and provides the major portion of resistance to race 3 and race 14 (Concibido et al 2004). Major quantitative trait loci (QTL) for resistance have been mapped across many resistance sources, including Peking and PI437654, PI90767, PI88788, PI209332, PI89772, and PI404198A (Concibido et al 1994(Concibido et al , 1996(Concibido et al , 1997(Concibido et al , 2004Webb et al 1995;Chang et al 1997;Heer et al 1998;Prabhu et al 1999;Meksem et al 2001a;Yue et al 2001;Guo et al 2006a), producing several loci and interactions among them (Huang et al 1997;Meksem et al 2001a;Concibido et al 2004). The QTL conferring the greatest level of resistance mapped to a genomic region containing rhg1 in linkage group (LG) G (Concibido et al 2004;Guo et al 2006a), and QTL clusters on each end of LG G were confirmed by meta-analysis, a statistical method for assessing whether QTLs detected on a linkage group map in different studies are located on the same locus or linked (Goffinet and Gerber 2000;Guo et al 2006b).…”

Stacking Resistance Alleles from Wild and Domestic Soybean Sources Improves Soybean Cyst Nematode Resistance

“…In the majority of the sources of resistance studied, the resistance gene rhg1 was mapped as a QTL onto chromosome 18 (formerly linkage group [LG] G). This gene was mapped in the SCN resistance sources PI 437654 (Webb et al, 1995), PI 209332 (Concibido et al, 1996), Peking, PI 90763, PI 88788 (Concibido et al, 1997;Glover et al, 2004), PI 89772 (Yue et al, 2001), PI 88287 (Bassuner et al, 2001), and PI 404198A (Guo et al, 2006). In addition, research showed that PI 437654 and PI 88788 have different alleles at rhg1 (Brucker et al, 2005).…”