梨园锈病发生调查及田间药剂防治研究

Investigation on Occurrence of Rust in Pear Orchard and Study on Field Chemical Control

[目的]明确梨锈病在安徽合肥地区的发生情况,筛选出防治梨锈病的有效杀菌剂并确定其防治最适用药间隔期。[方法]以5年生“砀山酥梨”为试材,通过监测田间梨锈病不同时间点的病斑数并测量每病斑大小,结合天气因素,调查梨锈病的发生情况。再选取11种杀菌剂并制定4种施药间隔期进行田间试验,筛选最佳的药剂以及施药间隔期。[结果]安徽合肥地区梨园叶片从4月上旬开始出现梨锈病病斑,4月中旬为发病高峰期,5月中旬病情稳定,不再发生新病情;且4月降雨量多是梨锈病发生的关键因素。11种杀菌剂对砀山酥梨梨锈病的防治试验表明,三唑类药剂腈菌唑和苯醚甲环唑优于其他9种药剂,其中农抗120、萎锈灵、腐霉利和甲基硫菌灵防治效果较差。间隔7 d或者间隔14 d施药都可以控制梨锈病发生率。[结论]在安徽合肥地区,选用腈菌唑或苯醚甲环唑分别在4月上旬发病初期和4月下旬发病高峰期分2次进行喷雾防治,能有效控制梨锈病。

[Objective]To identify the occurrence of pear rust in Hefei region of Anhui Province,screen out the effective fungicides for controlling pear rust and to determine the most suitable drug interval.[Method]Taking the 5-year-old‘Dangshansuli’as material,the incidence of pear rust was investigated by monitoring the number of spots at different time points and measuring the size of each spot,combined with weather factors.Then 11 fungicides were selected and 4 application intervals were established for field experiment to screen the best fungicides and application intervals.[Result]The leaves from early April began to appear pear rust spots,mid-April was the peak incidence,mid-May disease was stable,no longer occurring new disease of Anhui Hefei area pear orchard;Moreover,April rainfall was a key factor in the occurrence of pear rust.The control test of 11 fungicides on pear rust showed that the triazole-agents nitroconazole and phenotrimazole were better than other 9 agents,among which the control effect of agricultural resistance 120,chlorothalonil,rotothioxin and methylthioconazole were poor.Application at 7 days interval or 14 days interval could control the incidence of pear rust.[Conclusion]In Hefei region of Anhui Province,the pear rust can be effectively controlled by two sprays of azoxystrobin or phenoxymethoxazole in early onset of pear rust in the early April and the peak of the disease in late April,respectively.