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

Abstract

The soybean cyst nematode (SCN; Heterodera glycines Ichinohe) is the most economically important soybean [Glycine max (L.) Merr.] pathogen in the United States. Field SCN populations are adapting to the narrowly based SCN resistance currently deployed in soybean cultivars. The objective of our research was to measure the effects of combinations of SCN resistance genes or quantitative trait loci (QTL) from the wild soybean (Glycine soja Siebold & Zucc.) PI 468916 and the domesticated soybean accessions PI 88788 and PI 437654. Two populations were developed to test the combinations of QTL and genes. Both populations segregated for the G. soja resistance QTL cqSCN‐006 and cqSCN‐007. Population 1 also segregated for resistance from PI 88788 and Population 2 segregated for resistance from PI 437654. The populations were tested for resistance to three SCN isolates in a greenhouse and with single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers. In both populations, the two G. soja resistance alleles significantly increased SCN resistance compared with the alternative alleles. The SCN resistance alleles rhg1 and Rhg4 from PI 437654 and rhg1‐b from PI 88788 also significantly increased resistance compared with the alternative alleles. The two G. soja QTL alleles significantly enhanced the resistance derived from PI 88788. These results show that SCN resistance can be increased through stacking genes and QTL from multiple resistance sources.

Distinct Copy Number, Coding Sequence, and Locus Methylation Patterns UnderlieRhg1-Mediated Soybean Resistance to Soybean Cyst Nematode

“…LD is known to have SCN resistance derived from PI 437654 (low-copy Rhg1 locus type), while LDX contains a single copy of Rhg1 Kim et al, 2011). To confirm our observations and gain single-base resolution for methylation, we highlighted and reanalyzed the data of Schmitz et al (2013a), focusing on Rhg1.…”

“…SCN is found in all major soybean-growing states in the United States and cannot feasibly be removed (Niblack, 2005). Because the primary control strategies for SCN are crop rotation and planting resistant varieties, significant attention has been focused on the identification, development, and use of soybean germplasm that exhibits resistance to SCN (Diers et al, 1997;Concibido et al, 2004;Brucker et al, 2005b;Wrather and Koenning, 2009;Kim et al, 2010aKim et al, , 2011. The Rhg1 (for Resistance to Heterodera glycines) locus, sometimes in combination with Rhg4, makes the greatest contribution to resistance in the vast majority of the commercially utilized soybean cultivars that exhibit SCN resistance (Caldwell et al, 1960;Matson and Williams, 1965;Webb et al, 1995;Li et al, 2004;Brucker et al, 2005b;Tylka et al, 2012).…”

Identification of positive yield QTL alleles from exotic soybean germplasm in two backcross populations

“…For both soybean breeding and research, single nucleotide polymorphism (SNP) markers are becoming the marker of choice because of their high frequency, widespread distribution throughout the genome as well as their suitability for high-throughput automated genotyping (Choi et al 2007;Hyten et al 2010). Multiple Illumina GoldenGate assays with 384-1,536 SNP markers have been developed (Hyten et al 2008 and used in developing genetic maps , mapping genes conferring resistance to Asian soybean rust Chakraborty et al 2009), soybean cyst nematode (Heterodera glycines Ichinohe) (Vuong et al 2010;Kim et al 2011), and soybean aphid (Aphis glycines Matsumura) (Jun et al 2012), and mapping loci involved in isoflavone concentration (Gutierrez-Gonzalez et al 2011).…”

Investigation of Soybean Cyst Nematode Heterodera Glycines Type and Evaluation of Resistance on Soybean Varieties and Germplasms in Korea

“…1. Soybean cyst nematodes were increased from the five different soil samples to conduct further SCN test in the greenhouse (A), and Heterodera glycines type test were performed on SCN check varieties as described by Arelli et al (2000), Niblack et al (2002) and Kim et al (2011) in the thermo-regulated water bath system (B).…”

“…The HG type tests were initiated by germinating seeds of SCN check varieties in the sand soil plates for four days in the greenhouse. When roots reached approximately 3 cm in length, one seedling soybean plant was transplanted in each PVC tube that was previously infested with 2,000 eggs per plant as described by Kim et al (2011). The SCN bioassays were completed with three plant replications to the seven indicator lines, including Lee 74 as a SCN susceptible control soybean plant (Niblack et al, 2002).…”