解淀粉芽孢杆菌5号防控西瓜CGMMV机制初探

Preliminary Study on the Prevention and Control Effect of Bacillus amyloliquefaciens Strain 5 on Cucumber Green Mottled Mosaic Virus Disease on Watermelon

为筛选西瓜上黄瓜绿斑驳花叶病毒(cucumber green mottle mosaic virus,CGMMV)病害生物防治的有效生防菌剂,在接种CGMMV的西瓜幼苗上提前施用多粘类芽孢杆菌(Paenibacillus polymyxa)246-1号、贝莱斯芽孢杆菌(Bacillus velezensis)4-2号、解淀粉芽孢杆菌(B.amyloliquefaciens)5号生防菌剂,结果表明,多粘类芽孢杆菌246-1号、贝莱斯芽孢杆菌4-2号和解淀粉芽孢杆菌5号对CGMMV病害的防控效果分别达到了59.89%、46.71%和65.77%,其中解淀粉芽孢杆菌5号的防治效果最好。进一步测定21 d西瓜幼苗生理生化指标及表型变化,验证解淀粉芽孢杆菌前处理对CGMMV病害的防控效果,结果表明提前施用解淀粉芽孢杆菌5号后西瓜幼苗株高、根长、鲜质量和干质量比对照显著增加5.93 cm、2.92 cm、2.48 g、2.09 g;西瓜幼苗叶片净光合速率、气孔导度和蒸腾速率显著提高351.00%、133.33%、91.30%,胞间CO_(2)浓度显著降低25.88%;同时使西瓜幼苗SOD、POD、PAL和CAT活性显著提高100.37%、126.46%、98.45%和98.99%。综上,解淀粉芽孢杆菌5号通过提高植株生长发育、叶片光合作用能力和抗性酶活性,进而提高西瓜对CGMMV的抗性。

In order to screen for effective microbial agents against cucumber green mottled mosaic virus(CGMMV)disease on watermelon,Paenibacillus polymyxa 246-1,Bacillus velezensis 4-2,and B.amyloliquefaciens 5 microbial agents were applied in advance on watermelon seedlings inoculated with CGMMV.The results showed that P.polymyxa 246-1,B.velezensis 4-2,and B.amyloliquefaciens 5 control effects of CGMMV disease reached 59.89%,46.71%,and 65.77%,respectively.Among them,B.amyloliquefaciens 5 had the best prevention and control effect.Further determination of physiological and biochemical indicators and phenotypic changes in watermelon seedlings on the 21st day was conducted to verify the prevention and control of CGMMV disease by pre-treatment with B.amyloliquefaciens.The results showed that the application of B.amyloliquefaciens 5 microbial agent in advance significantly increased the plant height,root length,fresh weight,and dry weight of watermelon seedlings by 5.93 cm,2.92 cm,2.48 g,and 2.09 g compared to the control group;the net photosynthetic rate,stomatal conductance,and transpiration rate of watermelon seedlings significantly increased by 351.00%,133.33%,and 91.30%,while the intercellular CO_(2) concentration significantly decreased by 25.88%;simultaneously,the activities of SOD,POD,PAL,and CAT in watermelon seedlings were significantly increased by 100.37%,126.46%,98.45%,and 98.99%.In conclusion,B.amyloliquefaciens 5 can improve the resistance of watermelon to CGMMV by improving the growth and development of plants,the photosynthesis ability of leaves and the activities of resistant enzymes.