康氏木霉PLA_2基因的生物学功能及诱导玉米抗弯孢霉叶斑病作用

本研究从康氏木霉T30的cDNA中克隆了PLA2基因，然后用PLA2敲除突变株为材料在玉米接弯孢霉叶斑病菌的条件下研究此基因的生物学功能。敲除突变株P82（ΔPLA2）所分泌的胞外几丁质酶和β-1，3-半乳糖苷酶的酶活要比野生型低。玉米接种弯孢霉叶斑病菌条件下，突变株的生防实验表明其具有较好的诱抗作用。此基因大肠杆菌表达产物在离体玉米叶片上同对照相比产生更大的叶斑。PLA2基因在木霉对抗弯孢霉叶斑病菌同玉米互作可能是一种负调控方式，要对此基因与玉米的非亲和互作还需对此基因互补进行功能验证。

Biological Functions of the Gene PLA2 of T.koningii and its Induced Resistance Against Curvularia lunata

In this study,we cloned the gene of PLA2 from cDNA of the wide type T. teoningii T30,and then investigated the biological functions of the PLAe-deletion mutant and the role of PI.Ae demonstrated the interaction between maize and T. koningii after challenged inoculation with Curvularia lunata. The activity of exo-chitinase and 13-1, 3-glucanase of the mutant was a little lower than that of the wild type. Furthermore, the mutant provided a higher control of Curvularia leaf spot on the potted maize in comparison with the wild type strain. Similarly,it had been infiltrated with prokaryotic expression protein of PLA2 got larger lesions on the detached leaves than the controls. Thus we speculated that PI.A2 might be involved in the Trichoderma-induced maize defensive pathway against Curvularia leaf spot in a negativeregulation. The function of PLA2 in detail to non-compatible interaction between Trichoderma spp. and maize need to be further studied through its complemental experiments.