Burnett A L, Lalancette N, McFarland K A
Department of Plant Biology and Pathology, Rutgers Agricultural Research and Extension Center, Rutgers University, Bridgeton, NJ 08302-5919.
Plant Dis. 2010 Aug;94(8):1000-1008. doi: 10.1094/PDIS-94-8-1000.
Three studies were conducted to examine the curative activity of azoxystrobin, trifloxystrobin, and pyraclostrobin + boscalid against Monilinia fructicola, causal agent of brown rot on peach. In the first study, 'Autumnglo' peach trees were treated with each of the three fungicides both before and after fruit inoculation. In the second study, the effects of fungicide active ingredient, rate/volume, and inoculation timing were examined on inoculated 'Suncrest' peach fruit. Results of these studies showed that sporulating area, on average across all treatments, was reduced by 15.9, 42.4, and 0.4% for azoxystrobin, trifloxystrobin, and pyraclostrobin + boscalid, respectively. In any single treatment, trifloxystrobin provided the greatest benefit with two consecutive sprays, reducing sporulating area by 53 to 60%. In contrast to sporulation activity, the three fungicides exhibited less of an inhibitory effect on fruit colonization. When applied at maximum labeled rates in the various treatments, azoxystrobin, trifloxystrobin, and pyraclostrobin + boscalid reduced colony growth, on average, by 12.3, 7.5, and 7.4%, respectively. Because the pathogen was inoculated into the mesocarp, this low level of activity against colonization may be due to a lack of deeper systemic movement of the fungicides into fruit tissue. In the final study, the three fungicides were examined for their antisporulant activity on blossom blight twig cankers. Unlike results observed on fruit, significant reductions in spore production on cankers were observed for all three fungicides. Azoxystrobin, trifloxystrobin, and pyraclostrobin + boscalid provided 56, 71, and 53% reductions, respectively, in the number of conidia produced per unit canker length. Overall results of these studies indicated that quinone outside inhibitor fungicides, in addition to their known protectant activity, also possess varying levels of curative activity against M. fructicola. In particular, trifloxystrobin demonstrated good antisporulant activity on both fruit infections and cankers.
开展了三项研究，以检验嘧菌酯、肟菌酯以及唑醚·啶酰菌对桃褐腐病菌（Monilinia fructicola）的防治活性。在第一项研究中，对‘Autumnglo’桃树在果实接种前后分别用三种杀菌剂进行处理。在第二项研究中，考察了杀菌剂活性成分、施用量/施药体积以及接种时间对接种后的‘Suncrest’桃果实的影响。这些研究结果表明，在所有处理中，嘧菌酯、肟菌酯以及唑醚·啶酰菌使产孢面积平均分别减少了15.9%、42.4%和0.4%。在任何单一处理中，连续两次喷施肟菌酯的防治效果最佳，使产孢面积减少了53%至60%。与产孢活性相反，这三种杀菌剂对果实定殖的抑制作用较小。在不同处理中按最大标注剂量施用时，嘧菌酯、肟菌酯以及唑醚·啶酰菌使菌落生长平均分别减少了12.3%、7.5%和7.4%。由于病原菌接种到了中果皮中，这种对定殖的低活性可能是由于杀菌剂向果实组织内的深层系统移动不足所致。在最后一项研究中，考察了这三种杀菌剂对花腐病枝溃疡的抗产孢活性。与在果实上观察到的结果不同，所有三种杀菌剂均使溃疡病斑上的孢子产生量显著减少。嘧菌酯、肟菌酯以及唑醚·啶酰菌使每单位溃疡病斑长度产生的分生孢子数量分别减少了56%、71%和53%。这些研究的总体结果表明，醌外抑制剂类杀菌剂除了具有已知的保护活性外，对桃褐腐病菌还具有不同程度的治疗活性。特别是，肟菌酯在果实感染和溃疡病斑上均表现出良好的抗产孢活性。
