八种药剂对节瓜炭疽病菌的毒力测定与田间防效

Toxicity Test of Eight Fungicides to Chiehqua Colletotrichumand Control Effect in Fields

以节瓜品种"粤农"为试材,以节瓜炭疽病菌为防治对象,采用菌丝生长速率及农药田间药效试验方法,研究了8种药剂对节瓜炭疽病菌的室内毒力和田间防效,以期为海南节瓜炭疽病的防治提供参考依据。结果表明:代表菌株J-56与Colletotrichum gloeosporioides strain JX-1(HQ645079.1),Colletotrichum gloeosporioides isolate C16(KC010547.1)的ITS序列聚在同一分支上,同源性达99%,属于胶孢炭疽菌Colletotrichum gloeosporioides。室内毒力测定中,50%咪鲜胺锰盐WP和250g·L-1嘧菌酯SC毒力较高,EC50分别为0.000 9、0.012 7μg·mL-1,其次为43%戊唑醇SC、40%多·福·溴菌腈WP、80%代森锰锌WP、70%甲基托布津WP和10%苯醚甲环唑WG,20%嘧霉胺WP的毒力最低,EC50为60.511 9μg·mL-1。大田试验中,43%戊唑醇SC和50%咪鲜胺锰盐WP 2个处理防效较高,为80.64%和78.16%,但与10%苯醚甲环唑WG、40%多·福·溴菌腈WP和250g·L-1嘧菌酯SC 5个处理间防效相当,差异不显著;20%嘧霉胺WP处理的防效最低。结合室内毒力和大田试验,生产上可使用43%戊唑醇SC、50%咪鲜胺盐锰WP、10%苯醚甲环唑WG、40%多·福·溴菌腈WP和250g·L-1嘧菌酯SC 5种药剂防治节瓜炭疽病。

＇Yuenong＇ Chiehqua was used as material, and the Chiehqua Colletotrichurn was used as control object. Via the methods of pathogens mycelium growth rate and field trials of fungicides, the indoor toxicity and the control effect of 8 kinds of fungicides on the field anthracnose were studied, so as to provide reference for the prevention and control of melon anthracnose. The results showed that all of the ITS sequence which included Colletotrichum gloeosporioides strain JX-1 （HQ645079.1）,J-56 strain,Colletotrichum gloeosporioides isolate C16 （KC010547. 1） located in the same branch with sequence homology of 99 %. It belonged to Colletotrichurn gloeosporioides. 50% prochloraz manganese WP and azoxystrobin SC of 250 g · L-1 were highly toxic to this strain with EC50value of 0. 000 9μg · mL-1 and 0. 012 7 μg · mL-1, followed by 43% tebuconazole SC, 40% carbendazim thiram bromothalonil WP,80~ carmazine WP, 70% thiophanate methyl WP, 10% difenoconazole WG. 20% pyrimethanil WP had a little toxicity with EQovalue of 60. 511 9 μg· mL^-1. The field experiment results showed that 43 % tebuconazole SC and 500% prochloraz manganese WP had good control efficiency of 80. 64o//00 and 78. 16 %. But treatments of 43~ tebuconazole SC, 50% proehloraz manganese WP, 10% difenoconazole WG, 40% carbendazim thiram bromothalonil WP and azoxystrobin SC of 250 g · L-1 were fairly between each other, no significant difference. Treatment of 20% pyrimethanil WP had minimum control effect. According to indoor toxicity tests and field trails, 43 % tebuconazole SC, 50 % prochloraz manganese WP, 10 % difenoconazole WG, 40o//oo carbendazim thiram bromothalonil WP and azoxystrobin SC of 250 g · L-1 could be used to control Chiehqua Colletotrichum in turn in practical production.