7种杀菌剂对草坪草腐霉枯萎病菌的毒力测定与药效试验

采用生长速度法和孢子囊形成法测定了7种杀菌剂对草坪腐霉枯萎病菌的毒力作用，并进行了7种杀菌剂拌种的温室盆栽防治效果研究。室内毒力测定表明，不同杀菌剂对腐霉菌菌丝的生长和游动孢子囊的形成有显著的抑制作用（P<0.05）。对菌丝的生长有明显抑制效果的杀菌剂主要是霜脲锰锌、代森锰锌和霜霉威盐酸盐，前两种杀菌剂的半致死浓度（EC50）值均为1.28 mg·L-1，后者的EC50值为3.26 mg·L-1。对游动孢子囊的形成抑制效果明显的杀菌剂是吡唑醚菌酯、霜脲锰锌和代森锰锌，其EC50值分别是0.09 、0.21和0.46 mg·L-1。用7种杀菌剂分别拌种后，高羊茅(Festuca arundinacea)出苗率都有不同程度的提高，其中霜脲锰锌和代森锰锌对腐霉枯萎病的防治效果较好。根据杀菌剂的室内毒力测定和盆栽防效试验结果，霜脲锰锌和代森锰锌对腐霉枯萎病的防治效果优于其它5种杀菌剂。

The toxicities and effects text of seven fungicides on Pythium aphanidermatum

The toxicities of seven fungicides were tested by using mycelia growth rate method and inhibiting method of the formation of sporangium. Potted plants test were adopted by using seed treatment to test the control effect of Pythium aphanidermatum. Laboratory toxicity tests results indicated that the effects of these fungicides were significantly different in inhibiting the growth of mycelium and the formation of sporangium of P.aphanidermatum. Cymoxanil mancozeb, Mancozeb and Propamocarb had the better inhibiting effect on the mycelia growth and the EC50 values of these fungicides were 1.28, 1.28, 3.26 mg·L-1. While in the inhibiting experiment of the formation of sporangium of P.aphanidermatum, Pyraclostrobin, Cymoxanil mancozeb and Mancozeb performed well with the EC50 value 0.09, 0.21, 0.46 mg·L-1. After taking Fungicide seed treatments, all of tall fescue germination rate had different degrees of improvement, and Cymoxanil mancozeb and Mancozeb had the better control effect. Based on the results of the laboratory toxicity tests and pot tests, it's concluded that Cymoxanil mancozeb and Mancozeb on Pythium disease control effect is better than in the other five kinds of fungicides.