十种常用农药制剂对蜡蚧轮枝菌孢子萌发、菌丝生长和产孢的影响

Effects of Ten Common Pesticides on Conidial Germination,Mycelial Growth and Sporulation of Verticillium lecanii

真菌杀虫剂在有害生物综合治理中常与一些化学农药搭配使用。为了明确目前常用的农药品种与蜡蚧轮枝菌的相容性,本研究测定了北京市售的10种农药制剂对蜡蚧轮枝菌Verticillium lecanii孢子萌发、菌丝生长和产孢量的影响。对孢子毒力测试结果表明,45%咪鲜胺乳油、25.5%异菌脲悬浮剂、40%嘧霉胺悬浮剂和10.8%精喹禾灵乳油的毒力最强,LC50为2.27～5.58μg.mL 1;50%丙环唑可湿性粉剂、20%中生菌素可湿性粉剂、2.5%高渗吡虫啉可湿性粉剂和10.8%高效氟吡甲禾灵乳油的毒力居中,LC50为20.0～36.8μg.mL 1;72%2,4-滴丁酯乳油和48%氟乐灵乳油的毒力最弱,LC50分别为247.7μg.mL 1和376.62μg.mL 1。在田间推荐使用浓度下,供试农药制剂对蜡蚧轮枝菌孢子萌发、菌丝生长和产孢量均有显著抑制作用,其中2.5%高渗吡虫啉可湿性粉剂对孢子萌发的影响最小,抑制率为39.7%;20%中生菌素可湿性粉剂对菌丝生长和产孢量影响最小,抑制率分别为54.5%和34.8%。由此可知,蜡蚧轮枝菌与高渗吡虫啉和中生菌素具有一定的相容性,但相容值较低,田间应用需与之适当间隔,而与其余的8种农药则完全没有相容性。

Fungal insecticides are often used with chemical pesticides in integrated pest management. Effects often pesticides on current Beijing market on conidial germination, mycelial growth and sporulation of Verticillium lecanii were tested in order to investigate the compatibility between the fungus and the pesticides. The results showed that prochloraz 45% EC, iprodione 25.5% SC, pyrimethanil 40% SC and quizalofop-p-ethyl 10.8% EC had highest toxicity to conidial germination of the fungus with LC50 ranging from 2.27-5.58 μg.mL-1. The LCs0 of propiconazo150% WP, zhongshengmycin 20% WP, imidacloprid 25% WP and haloxyfop-R-methyl 10.8% EC were middle, ranging from 20.0--36.8 μg.mL-1. Toxicity of 2,4-D butylate 72% EC and trifluralin 48% EC to conidial germination of the fungus were lowest with LC50 247.7 μg·mL-1 and 376.62μg.mL-1 respectively. At the field recommended concentration, all pesticides had significant influence on conidial germination, mycelial growth and sporulation of the fungus. Imidacloprid 25% WP had the lowest effect on conidial germination, the inhibiton rate by which was 39.7%. Moreover zhongshengmycin 20% WP had the lowest effect on mycelial growth and sporulation with the inhibition rate 54.5% and 34.8% respectively. Consequently imidacloprid 25% WP and zhongshengmycin 20% WP had certain compatibility with the fungus, while other eight pesticides were hardly compatible with the fungus.