防治黄瓜疫病的药剂筛选

SCREENING ON FUNGICIDE COMBINATION FOR CONTROL OF PHYTOPHTHORA 

为了筛选防治黄瓜疫病的有效药剂，研究了６种作用机理不同的杀菌剂及其两两混用对黄瓜疫病病菌生长的抑制作用．单剂以甲霜灵对疫霉菌生长的抑制作用最强，有效中浓度（ＥＣ５０）为０．３０１５μｇ／ｍＬ；敌克松的效果次之，ＥＣ５０为５．０１３２μｇ／ｍＬ．甲霜灵＋乙膦铝、甲霜灵＋百菌清、代森锰锌＋乙膦铝、代森锰锌＋百菌清、甲基托布津＋百菌清等５种组合有较明显的增效作用，其共毒系数（ＣＴＣ）分别是１５６．３６，１３９．６５，１６４．６４，２６６．３９和４２４．４．室内盆栽和大田试验的结果表明：甲霜灵＋百菌清、代森锰锌＋百菌清。

6 fungicides and their combinations of 1∶1 ratio were studied on inhibiting Phytophthora growth. Results show that Ridomil is best with EC50 0.301 5, followed by Dexon(EC50 5.013 2). In fifteen 1∶1 combinations, Ridomil+Aliette,Ridomil+Daconil,Mancazeb+Aliette,Mancazeb+Daconil,TopsinM+Daconil have obvious enlargement,their CTC are 15636,13965,16464,26639,4244, respectively. Ridomil+Daconil,Mancazeb+Daconil,TopsinM+Daconil are tested in greenhouse and in field.Results show that Ridomil+Daconil,Mancazeb+Daconil,TopsinM+Daconil are better than Ridomil on controlling Phytophthora melonis.