RNA-seq-based identification of potential resistance genes against the soybean cyst nematode (Heterodera glycines) HG Type 1.2.3.5.7 in ‘Dongnong L-10’

Abstract

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is a parasitic plant pathogenic nematode that severely affects the growth and development of soybean. Breeding SCN-resistant varieties is one of the safest and most effective ways to manage SCN. ‘Dongnong L-10’ is a well-known SCN-resistant variety in Northeast China, but the molecular mechanisms governing this resistance have not been determined. Hence, in this study, we transcriptome sequenced the roots of ‘Dongnong L-10’ (Resistant varieties of SCN race 4) and ‘Heinong 37’ (Susceptible varieties of SCN race 4) under the stress of HG Type 1.2.3.5.7 (SCN race 4). We obtained a total of 76.75 GB of the raw reads. A total of 4400 and 5724 differentially expressed genes (DEGs) were related to the SCN resistance of ‘Dongnong L-10’ and ‘Heinong 37’. The analysis of DEGs showed that transcription factors (AP2/EREBP, WRKY, MYB, NAC, bHLH and C2H2) and plant hormone signal transduction pathways (the jasmonic acid and salicylic acid pathways) may be involved in the response of soybean to HG Type 1.2.3.5.7. RT-qPCR analysis showed that the relative expression levels of PR protein family gene GmRSCN4-1 (Glyma.05G204800) and cytochrome P450 family gene GmRSCN4-2 (Glyma.16G195600) in ‘Dongnong L-10’ were significantly higher than those in ‘Heinong 37’. Overexpression of GmRSCN4-1 and GmRSCN4-2 in soybean hairy roots resulted in increased HG Type 1.2.3.5.7 resistance in soybean hairy roots. Our results not only provide a theoretical basis for analyzing the resistance mechanism of ‘Dongnong L-10’ to HG Type 1.2.3.5.7, but also provide some genes resources for soybean molecular breeding for resistance to cyst nematode.