烟草赤星病防治药剂的筛选

Fungicide screening against tobacco brown spot

为筛选防治烟草赤星病的高效杀菌剂,测定了5种常用药剂(氟啶胺、啶氧菌酯、啶酰菌胺、嘧菌环胺、噁唑菌酮)对烟草赤星病菌(Alternaria alternata)的室内毒力及田间防效。结果表明,98%氟啶胺对病菌菌丝生长的抑制活性最强,EC_(50)为0.138 2 mg/L,其次为95%嘧菌环胺,EC_(50)为3.568 9 mg/L,而95%噁唑菌酮最弱,EC_(50)为30.098 3 mg/L。田间防效试验表明,5种杀菌剂中以50%氟啶胺SC和62%嘧菌环胺WG的防治效果较好,防效分别为70.44%和63.09%;以50%啶酰菌胺WG防治效果最差,为39.53%。综合室内毒力和田间防治试验结果,在烟草赤星病防治中推荐氟啶胺和嘧菌环胺。

To screen highly effective fungicides against tobacco brown spot caused by Alternaria alternata,indoor toxicity and field efficacy of five common fungicides(fluazinam,picoxystrobin,boscalid,cyprodinil and famoxadone)against A.alternata were determined.The results showed that fluazinam had the strongest inhibitory activity against mycelial growth,around 98%;this was followed by cyprodinil and famoxadone at 95%.The EC50 of 98%fluazinam,95%cyprodinil and 95%famoxadone for the mycelial growth of A.alternata were 0.138 2,3.568 9 and 30.098 3 mg/L,respectively.The control efficacy of 50%fluazinam SC and 62%cyprodinil WG in field trials reached 70.44%and 63.09%,respectively.The field control efficacy of 50%boscalid WG was the worst,at only 39.53%.On the basis of these results,fluazinam and cyprodinil were recommended to control tobacco brown spot.