防治玉米顶腐病和黑粉病药剂筛选

采用10种杀菌剂对玉米顶腐病菌室内测定结果表明，80%多&;#8226;福&;#8226;福锌可湿性粉剂、70%多&;#8226;福可湿性粉剂、97%多菌灵可湿性粉剂和98%烯唑醇可湿性粉剂抑菌效果最好，而且持效期较长。以97%多菌灵可湿性粉剂和98%烯唑醇可湿性粉剂按3〖DK1〗∶1或4〖DK1〗∶1的比例进行复配，抑菌效果达到了其各自单用的抑菌效果。经安全性测定，用98%烯唑醇可湿性粉剂进行种子包衣在低温条件下对玉米出苗和苗期生长有一定影响，97%多菌灵可湿性粉剂则无影响。田间防治试验表明，97%多菌灵可湿性粉剂或97%多菌灵可湿性粉剂与98%烯唑醇可湿性粉剂复配对玉米顶腐病和瘤黑粉病均有一定防效。在玉米4～8叶和8～12叶期时，以97%多菌灵可湿性粉剂20 g+有机硅5 mL/666.7 m2和97%多菌灵可湿性粉剂25 g+98%烯唑醇可湿性粉剂5 g+有机硅7 mL/666.7 m2用量分别喷洒，对顶腐病的防治效果达90%左右，并可兼治瘤黑粉病，防治效果达70%左右。

Fungicides for controlling the corn top rot and corn smut diseases

Ten fungicides were selected to control Fusarium subglutinans in the laboratory. The results showed that 80% carbendazim&;#8226;thiram&;#8226;ziram WP, 70% carbendazim&;#8226;thiram WP, 97% carbendazim WP and 98% diniconazole WP could remarkably inhibit pathogens, and the inhibition duration was long. The inhibition effect of 97% carbendazim&;#8226;98% diniconazole WP, with the ratio of 3∶1 or 4∶1, had the same effect as 97% carbendazim WP or 98% diniconazole WP. Safety testing showed that 98% diniconazole WP seriously affected the germination of maize seeds and growth of seedlings, while 97% carbendazim WP had no effects on the germination of maize seeds and growth of seedlings. Control efficacy tests in fields indicated that the control effect of 97% carbendazim WP or 97% carbendazim&;#8226;98% diniconazole WP could control corn top rot and corn smut diseases. By spraying 20 g 97% carbendazim WP and 5 mL silicone per 666.7 m2 or 25 g 97% carbendazim WP and 5 g 98% diniconazole WP and 7 mL silicone per 666.7 m2 during 4-8 leaf and 8-12 leaf stages, the control efficiency of corn top rot disease was about 90%. They could also control corn smut disease, and the control efficiency was about 70%.