Abstract
Heterodera glycines is one of the most destructive pathogens of soybean. Soybean seeds coated with Bacillus simplex Sneb545 have shown resistance to H. glycines as a result of induced systemic resistance (ISR) in the plants. In this study, we aimed to identify the resistance-inducing determinants from this B. simplex strain. Combining the ISR bioassay, six ISR-active compounds were isolated from a culture of B. simplex Sneb545 using organic solvent gradient extraction, silica gel column chromatography, Sephadex LH-20 column chromatography, and semi-preparative high-performance liquid chromatography (HPLC), and all systems were based on activity tracking. The compounds were determined as cyclic(Pro-Tyr), cyclic(Val-Pro), cyclic(Leu-Pro), uracil, phenylalanine, and tryptophan using 1H NMR and 13C NMR. In plants from seeds coated with Bacillus simplex Sneb545, these six ISR-active compounds delayed the development of H. glycines in soybean roots. Moreover, cyclic(Pro-Tyr), cyclic(Val-Pro), and tryptophan reduced the number of nematodes in soybean roots. The expression levels of defense-related genes with cyclic(Val-Pro), tryptophan and uracil treatment soybean analysed using Quantitative real-time PCR (qRT-PCR). The results indicate cyclic(Val-Pro), tryptophan and uracil induced the expression of defense-related genes involved in the SA- and JA-pathways to against H. glycines. Our research results provide new agents for the control of H. glycines.
Highlights
Soybean is an important economic crop, which is widely used in oil and food production
The results indicate that the J4 ratio was 59.8% in the fermentation supernatant treatment, which was significantly lower than the 71.1% in the bacterial suspension treatment and the 72.1% in the control (Fig. 1A)
Previous studies revealed that soybean seeds coasted with a fermentation broth of B. simplex Sneb[545] showed reduced infestation and delayed development of nematodes as a result of ISR30,31
Summary
Soybean is an important economic crop, which is widely used in oil and food production. Heterodera glycines (soybean cyst nematode, SCN) is one of the most destructive pathogens of s oybean[1]. Drug tolerance of nematodes has been enhanced by the long-term use of chemical n ematicides[4,5] It is necessary, to seek safe, effective, and environmentally friendly products to defend soybean plants against S CN6. Secondary metabolites produced by PGPR, identified as ISR determinants, play a role in resisting plant pathogens by triggering the ISR r esponse[16,17,18]. Studies have shown that soybean seeds coated with Bacillus simplex Sneb[545] showed reduced infection and delayed development of pathogenic nematodes by triggering ISR30,31. Our research results provide new agents for the control of H. glycines
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
