种子处理诱导大豆抗胞囊线虫病的生防细菌筛选与鉴定

国内研究了简单芽孢杆菌Bacillussimplex包衣处理大豆种子，诱导大豆植株抗胞囊线虫的侵染。采用温室盆栽试验，对研究室通过2年田间试验筛选出的3株生防细菌进行复筛，获得最优菌株Sneb545；为了阐明其作用方式，设计了裂根试验验证菌株Sneb545诱导大豆产生抗胞囊线虫的能力，并对菌株Sneb545进行种水平鉴定。结果表明，菌株Sneb545处理种子后可以诱导苗期大豆对第一代胞囊线虫产生明显的抗性，线虫入侵总数显著降低，较对照降低72．63％，胞囊抑制率达70．63％；裂根试验结果证明，菌株Sneb545能够诱导大豆对胞囊线虫产生很强的抗性，菌株Sneb545在挑战根系中接种后，应答根系中胞囊线虫入侵量降低51．27％，土壤中胞囊减少65．82％；经形态学特征、生理生化试验测定及16SrDNA序列同源性分析，确定该菌株为简单芽孢杆菌。

Screening and Identification of Bacterium to Induce Resistance of Soybean against Heterodera glycines

Soybean plants are able to develop resistance against Heterodera glycines when coated with Bacillus simplex. Three bio-control bacteria were selected after a two-year field experiment. Among them, strain Sneb545 was proven effective by pot culture in greenhouse. In order to elucidate the modes of action, the split-root experiment was designed to investigate Sneb545＇s ability to induce soybean systemic resistance against H. glycines. The results showed that soybean seeds treated with strain Sneb545 were able to produce seedlings that had notable resistance to first generation cyst nematodes. Number of H. glycines cyst in soybean roots decreased by 72.63% comparing with control, the ratio of/-/, glyeines in adjacent soil to soybean root decreased by 70.63%. Split-root experiment concluded that after inoculating Sneb545 in the challenging roots, nematodes penetration in responding roots decreased by 51.27%, number of cyst in soil decreased by 65.82%. Sneb545 was identified as B. simplex based on morphological, physiological, biochemical characteristics and 16S rDNA sequence analysis.