灭黑一号防治水稻后期主要病害的药效研究

目的]扩大灭黑一号在水稻上的杀菌谱和应用效应。方法]以枯草芽孢杆菌和井冈霉素为对照药剂,在水稻孕穗期和破口期前5 d各施药一次,研究不同用量的灭黑一号对水稻纹枯病、稻曲病的防治效果。结果]一次用药后,灭黑一号对纹枯病的防治效果低于对照药剂,且与用量呈反向效应;二次用药后,各处理的防效明显提高,灭黑一号600 g/hm2的防效最高,病株率、病指的防效分别为96.14%、97.50%。灭黑一号防治稻曲病的效果与用量呈正向效应,450 g/hm2以上用量处理的防效在60%以上,大于对照药剂。结论]灭黑一号在水稻孕穗期和破口期前连续用药两次可以有效防治水稻纹枯病和稻曲病。

Study on the Efficacy of Miehei 1 on Controlling the Main Diseases in Rice in the Late Growth Stage

Objective] The study aimed to expand the fungicidal spectrum and application effect of Miehei 1 on rice.Method] With Bacillus subtilis and validamycin as contrast fungicides,the tested fungicides were applied once in each of the booting stage of rice and the first 5 d before heading stage so as to study the control effects of Miehei 1 at different dosages on rice sheath blight and rice false smut.Result] After the first application,the control effect of Miehei 1 on sheath blight was lower than that of contrast fungicides and showed contrarian effect on dosage.After the second application,the control effect in each treatment increased significantly,that of Miehei 1 at 600 g/hm2 was highest and that on its diseased plant rate and disease index were 96.14% and 97.50% resp.The control effect of Miehei 1 on rice false smut showed positive effect on dosage,that of dosage over 450 g/hm2 was more than 60% and bigger than that of contrast fungicides.Conclusion] Continuous twice applications of Miehei 1 in the booting stage of rice and before heading stage could effectively control rice sheath blight and rice false smut.