多菌灵、三环唑对大丽轮枝菌微菌核、黑色素形成及致病力的影响

 在离体和活体条件下测定了多菌灵、三环唑对大丽轮枝菌的微菌核黑色素形成的影响,以及经2种杀菌剂处理产生的形态变异菌株对棉苗的致病力。结果表明:多菌灵在培养基内含量超过0.1μg/ml时,即可抑制大丽轮枝菌微菌核的形成,随着培养基内多菌灵浓度的增加,微菌核形成时间逐渐延长,形成量逐渐减少;三环唑浓度为0.5μg/ml时,可抑制微菌核的黑色素形成,微菌核从黑色变为浅红至红褐色。三环唑对微菌核黑色素形成呈可逆抑制,变色的微菌核菌落移入不含药的培养基后,大多可恢复形成黑色素。培养基内三环唑浓度的提高,也可抑制大丽轮枝菌微菌核的形成;因2种杀菌剂的抑制而丧失形成微菌核的白色菌丝体移入不含药的培养基,微菌核形成能力也不能恢复。多菌灵和三环唑经棉株吸收后均能抑制植株内大丽轮枝菌微菌核的形成,但对微菌核色素的形成未见有明显影响。2种杀菌剂处理产生的形态变异菌株的致病力与野生型菌株致病力差异不显著。

EFFECT OF CARBENDAZIM AND TRICYCLAZOLE ON MICROSCLEROTIA AND MELANIN FORMATION OF VERTICILLIUM DAHLIAE

The effect of carbendazim and tricyclazole on microsclerotia and melanin formation of Verticillium dahliae were tested in vitro and in vivo Carbendazim at 0 1μg/ml primarily inhibited microsclerotia formation in straints and albino variants happened The time for microsclerotia formation was delayed and the amount of microsclerotia were decreased with the increased concentration of carbendazim Tricyclazole at 0 5μg/ml initially inhibited melanin biosynthesis in V. dahliae and a reddish pigmentation was instead The melanin variants reversed and the albino variants were stable after several mass transfer to PDA There was no significant change in virulence between morphological variants and parental isolates The albino variants were produced after watering the fungicides to cotton which pre inoculated with the pathogen.