小麦茎基腐病防治药剂及抗病品种的筛选

为获得防治小麦茎基腐病的有效药剂和抗病品种，测定12种杀菌剂对小麦茎基腐主要病原菌假禾谷镰孢菌Fusarium pseudograminearum的室内毒力、对小麦生长的影响及对小麦茎基腐病的室内防治效果，并鉴定144份小麦品种（系）对茎基腐病的抗性。结果表明，12种杀菌剂对假禾谷镰孢菌均有一定的抑制效果，其中15%氰烯菌酯·5%己唑醇的抑制率最高，EC₅₀为0.002 mg/L，其次是6.6%嘧菌酯·1.1%咯菌腈·3.3%精甲霜灵、25 g/L咯菌腈和430 g/L戊唑醇，EC₅₀分别为0.016、0.069和0.099 mg/L。12种杀菌剂拌种处理对小麦出苗、株高、根长和鲜重均有不同程度的影响，尤其对出苗率影响最大，其中15%氰烯菌酯·5%己唑醇处理的出苗率最低，为30.41%。15%氰烯菌酯·5%己唑醇拌种处理的防治效果最好，为70.43%；其次是430 g/L戊唑醇和25 g/L咯菌腈·37.5 g/L精甲霜灵，防治效果分别为56.34%和53.34%。在供试144份小麦品种（系）中，仅3份对小麦茎基腐病表现为中感，其余141份均表现为高感，无免疫和抗病品种。综上，目前防治小麦茎基腐病时建议选用15%氰烯菌酯·5%己唑醇等杀菌剂进行拌种处理，但应严格控制药剂用量，以防影响小麦出苗。

Screening of fungicides and disease-resistant varieties for wheat Fusarium crown rot

To obtain effective fungicide and resistant varieties for the control of wheat Fusarium crown rot (FCR), 12 different types of fungicides were selected to test the laboratory virulence against FCR fungi, their effects on wheat growth and the indoor efficacy in the control of wheat FCR. In addition, the resistance of 144 wheat varieties (lines) for resistance to wheat FCR were identified. The results showed that all 12 fungicides showed some inhibitory effect on F. pseudograminearum, among which the highest inhibition rate was 15% phenamacril·5% hexaconazole with the EC₅₀ of 0.002 mg/L, followed by 6.6% azoxystrobin·1.1% fludioxonil·3.3% metalaxyl-M, 25 g/L fludioxonil, and 430 g/L tebuconazole with EC 50 of 0.016, 0.069, and 0.099 mg/L, respectively. Twelve fungicides seed dressing treatments had different effects on wheat emergence, plant height, root length, and fresh weight, especially on emergence rate, among which the lowest wheat emergence rate was 30.41% produced by treatment with 15% phenamacril·5% hexaconazole. The indoor potted control effect test showed that the control efficacy of 15% phenamacril·5% hexaconazole was the optimal, 70.43%; followed by 430 g/L tebuconazole and 25 g/L chlorfenapyr·37.5 g/L fenpropathrin, the control efficacy were 56.34% and 53.34%, respectively. Among the 144 wheat varieties (lines) tested, only three were moderately susceptible, the other 141 were highly susceptible, there were no immune or resistant varieties. In conclusion, it is suggested to use 15% phenamacril·5% hexaconazole for seed dressing treatment, but the dosage of these agents should be strictly controlled to prevent the side-effect on wheat.