5种化学药剂对梨黑斑病菌的室内防治研究

Research on Prevention and Control of Five Chemical Agents Against Alternaria sp.

【目的】梨树的病虫害严重影响着梨产业的发展,由链格孢真菌侵染引起的梨黑斑病是侵染梨树的主要病害之一,为筛选出预防和治疗梨黑斑病的高效化学药剂,开展了5种化学药剂对梨黑斑病菌的室内防效试验。【方法】从常用的药剂中挑选10%中生·寡糖素、1.26%辛菌胺醋酸盐、15%络氨铜、20%吡唑醚菌酯和60%多菌灵5种化学药剂,采用体外接种法对梨黑斑病进行室内防治效果研究。【结果】5种化学药剂对梨黑斑病的生长都有一定的防治作用,但预防和治疗的效果不同。其中预防效果最好的是20%吡唑醚菌酯,在浓度为1000 mg/L时,其病斑平均直径为0.12 mm,防效达到94.8%,EC_(50)为3.31201 mg/L;其次为1.26%辛菌胺醋酸盐、15%络氨铜和60%多菌灵,在浓度1000 mg/L时,防效分别为90.1%、69.1%和60.1%;预防作用最差的是10%中生·寡糖素,在浓度62.5 mg/L时,其病斑平均直径为1.67 mm,防效仅为28.3%,EC_(50)为334.470 mg/L。治疗效果最好的为20%吡唑醚菌酯,在浓度1000 mg/L时,其菌落生长量平均直径为0.27 mm,抑制率达到了77.5%;最差的是60%多菌灵,在浓度62.5 mg/L时,抑制率为-6.7%。【结论】试验筛选出对梨黑斑病防治效果最好的药剂为20%的吡唑醚菌酯。

【Objective】Pear diseases and insect pests seriously affect the development of pear industry.Pear black spot disease caused by Alternaria sp.Infection,which is one of the main diseases infected pear trees in order to screen out high-efficiency chemical agents for preventing and controlling Alternaria sp.【Methods】The Five chemical agents were selected and identified from commonly used pesticides(10%Zhongsheng·Oligosaccharin,1.26%siminamine acetate,15%copper citrate,20%pyraclostrobin and 60%carbendazim).In vitro inoculation method was used to study the indoor control effect of Alternaria sp.disease.【Results】The results showed that the five chemical agents had certain control effects on the growth of Alternaria sp.,but the effects of prevention and treatment were different.Among them,the best preventive effect was 20%pyraclostrobin.When the concentration was 1000 mg/L,the average diameter of the lesion was 0.12 mm,the control effect was 94.8%,and the EC_(50)was 3.31201 mg/L;the control effects were 90.1%,69.1%and 60.1%at the concentration of 1000 mg/L,respectively,followed by 1.26%octylamine acetate,15%complex ammonia copper and 60%carbendazim.The worst preventive effect was 10%.At the concentration of 62.5 mg/L,the average diameter of the lesion was 1.67 mm,the control effect was only 28.3%,and the EC_(50)was 334.470 mg/L.The best therapeutic effect was 20%pyraclostrobin.When the concentration was 1000 mg/L,the average diameter of colony growth was 0.27 mm,and the inhibition rate reached 77.5%.The worst was 60%carbendazim,at a concentration of 62.5 mg/L,the inhibition rate was-6.7%.【Conclusion】The 20%pyraclostrobin has the best control effect on Alternaria sp.