诱导玉米抗弯孢菌叶斑病促生细菌的鉴定及生防效果评价

玉米弯孢菌叶斑病是玉米生产上的重要病害之一。［目的］为获得一株有效的抗玉米弯孢菌叶斑病的生防细菌,［方法］本研究采用生防细菌包衣处理玉米种子的方法,将前期田间初筛得到的4株生防促生细菌进行室内和田间防效评估,获得一株防效最好的菌株。进一步通过室内和田间试验验证该菌株对玉米的促生和增产作用,并采用形态学、生理生化和分子生物学分析方法对其进行鉴定。［结果］结果表明,4株生防细菌中,菌株Sneb2249对玉米弯孢菌叶斑病的防效最好,盆栽防效为55.04%,田间防效为39.36%。室内促生和田间测产试验结果显示,菌株Sneb2249能够显著促进玉米植株生长,其株高、地上部干重和千粒重分别比对照提高24.89%、49.15%和 7.9%。经鉴定菌株Sneb2249为恶臭假单胞菌(Pseudomonas putida)。［结论］恶臭假单胞菌Sneb2249是一株优良的植物根际促生菌,既可抗弯孢叶斑病菌,又对玉米具有促生增产作用。利用有益微生物处理种子防控病害将是一种新型的植保措施,具有重要的研究意义。

Identification and Biocontrol Effect of Growth Promoting Bacteria to Induce Resistance Against Curvularia Leaf Spot in Maize

Curvularia leaf spot is a major disease in maize. To screen biocontrol bacteria which efficiently induce resistance against Curvularia leaf spot, four biocontrol bacteria that could induce resistance against Curvularia leaf spot in maize were evaluated with seed coating in pot and field experiments, and the one with best effect on maize growth and yield was also verified. The species identification was performed based upon morphological, physiological and biochemical, and molecular biological methods. The results showed that among the four strains, Sneb2249 exhibited maximum resistance against Curvularia leaf spot, with control effect of 55.04% and 39.36% in pot and field experiments, respectively. Sneb2249 could significantly promote the growth of maize plants: plant height, dry weight of the overground part, and thousand kernel weight were improved by 24.89%, 49.15%, and 7.97%, respectively. Finally, Sneb2249 was identified as Pseudomonas putida. Sneb2249 is an excellent plant growth promoting rhizobacteria that could induce resistance against Curvularia leaf spot and promote the growth and yield of maize. Moreover, our results indicated that seed coating with beneficial microorganisms is a valid plant protection measure for disease control.