Abstract:
Wheat stripe rust is globally one of the most important diseases affecting wheat. There is an urgent need to develop environmentally safe and durable biological control options to supplement the control that is achieved with breeding and fungicides. In this study, endophytic bacteria were isolated from healthy wheat through the tissue separation method. Antagonistic endophytic bacteria were screened based on the control effect of urediniospore germination and wheat stripe rust (WSR). The taxonomic status of antagonistic strains was determined based on morphological, physiological, and biochemical characteristics and molecular biological identification (16S rDNA and gyrB gene sequence analysis). Finally, the potential growth-promoting effect of different concentrations of antagonists on wheat seedlings and the biological control effect of WSR were studied. A total of 136 strains of endophytic bacteria belonging to 38 genera were isolated. Pseudomonas was the most common bacterial genus, with 29 isolates (21%). The biological control effect of different isolates was assessed using an urediniospore germination assay. The isolate XD29-G1 of Paenibacillus polymyxa had the best performance, with 85% inhibition of spore germination during primary screening. In the deep screening, the control effect of XD29-G1 on wheat stripe rust was 60%. The antagonist XD29-G1 promoted the germination of wheat seeds and the growth of wheat seedlings at a solution dilution of 10-7 cfu/mL. The pot experiment results showed that different dilution concentrations of the strain had different levels of antibacterial activity against WSR, with the concentration of 10-1 cfu/mL having the best control effect and a control efficiency of 61.19%. XD29-G1 has better biological control potential against wheat stripe rust.
摘要:
小麦条锈病是全球范围内影响小麦的最重要的病害之一。迫切需要开发环境安全和持久的生物防治选择,以补充利用育种和杀真菌剂实现的防治。在这项研究中,通过组织分离法从健康小麦中分离出内生细菌。根据脲醛树脂孢子萌发和小麦条锈病(WSR)的防治效果,筛选了拮抗内生细菌。根据形态学确定拮抗菌株的分类地位,生理,生化特征和分子生物学鉴定(16SrDNA和gyrB基因序列分析)。最后,研究了不同浓度拮抗剂对小麦幼苗的潜在促生长作用以及WSR的生物防治作用。共分离出38属136株内生菌。假单胞菌属是最常见的细菌,29株(21%)。使用urediniospore萌发测定法评估了不同分离株的生物防治作用。分离的多粘类芽孢杆菌XD29-G1具有最好的性能,在初筛期间孢子萌发抑制85%。在深度筛选中,XD29-G1对小麦条锈病的防治效果为60%。拮抗剂XD29-G1在10-7cfu/mL的溶液稀释下促进了小麦种子的萌发和小麦幼苗的生长。盆栽试验结果表明,不同稀释浓度的菌株对WSR具有不同的抑菌活性,浓度为10-1cfu/mL时,控制效果最佳,控制效率为61.19%。XD29-G1对小麦条锈病具有较好的生物防治潜力。