嘧菌酯与苯醚甲环唑混用防治西瓜炭疽病、枯萎病及对西瓜品质的改善

The efficacy of the mixture of azoxystrobin and difenoconazole on the control of both watermelon-anthracnose and watermelon Fusarium wilt and the improvement of watermelon qualities

为了获得能同时防治西瓜炭疽病和枯萎病的有效药剂,在室内用菌丝生长抑制法和孢子萌芽法研究了嘧菌酯与苯醚甲环唑混剂对两种病原菌的作用效果及最适混用配比,并在温室和田间分别测定了该配比混剂的防治效果及其对改善大田西瓜品质的作用。结果表明:嘧菌酯与苯醚甲环唑以1∶2混配时效果最佳,对西瓜尖孢镰刀菌、瓜类炭疽病菌菌丝生长的共毒系数(CTC)分别为220.81和242.64,对孢子萌芽的CTC分别为282.73和547.56。该配比的混剂在温室与大田施用浓度为0.12gai/L时效果最好,对西瓜炭疽病,温室中预防和治疗效果分别为78.20%和73.00%,大田2次与3次施药防治效果分别为76.48%和76.32%;对西瓜枯萎病,温室中预防和治疗效果分别为79.16%和83.33%,大田使用2次与3次时,防治效果分别为77.27%和71.43%;大田施用时,西瓜的VC含量、含糖量、可溶性固形物含量、产量分别提高51.16%、13.64%、15.45%和22.58%。

The mycelial growth inhibition method and spore germination inhibition method were used to assess the efficacy of the mixture of azoxystrobin and difenoconazole to control Fusarium oxysporum f. sp. nveum and Colletotrichum lagenarium. Experiment results showed the mixture at the rate of 1 ： 2 （ azoxystrobin ： difenoconazole） could take the best efficacy on the inhibition of mycelial growth and spore germination. The CTC of the mixture to inhibit the mycelial growth of Fusarium oxysporum f. sp. nveum and Colletotrichum lagenarium was 220.81 and 242.64 respectively. The CTC to inhibit the spore germination of two pathogens was 282.73 and 547.56 separately. The concentration of 0.12 g ai/L of the mixture could take the best effect. The prevention and therapy effect on the watermelon-anthracnose in the greenhouse was 78.20% and 73.00%, respectively. Meanwhile the therapy effect in the field was 76.48% and 76.32% separately. Furthermore, in the greenhouse the prevention and therapy effect on watermelon Fusarium wilt was 79.16% and 83.33%, while in the field the therapy effect after two and three times treatment was 77.27% and 71.43%, respectively. In addition, the mixture of azoxystrobin and difenoconazole with concentration of 0.12g ai/L could improve the watermelon＇ s quantities of vitamin C, sugar, soluble solid product, with the increasing ratio of 51.16%, 13.64%, 15.45% and 22.58%, respectively.