苗菌敌对茄子黄萎病菌的室内毒力测定

采用生长速率法测定结果表明:杀菌剂苗菌敌对茄黄萎病菌(Verticillium albo-atrum Reinke et Beinth)的4个分离菌株的菌丝生长具有较强的抑制作用。在药剂含量为0.001～0.500 mg/mL的PDA培养基上接菌72 h后,兰州枯死菌株菌丝生长的相对抑菌率为28.91 %～100 %,毒力回归式为Y=2.372 7+1.304 7x,EC50=0.010 32 mg/mL;兰州普通型菌株菌丝生长的相对抑制率为20.14 %～100 %,毒力回归式为Y=2.095 14+1.401 6x,EC50=0.011 82 mg/mL;天水分离菌株菌丝生长的相对抑制率为19.30 %～100 %,毒力回归式为Y=1.909 9+1.498 9x,EC50=0.011 52 mg/mL;白银分离菌株菌丝生长的相对抑制率为33.36 %～100 %,毒力回归式为Y=2.453 6+1.324x,EC50=0.008 364 mg/mL。相关分析表明,以上几种分离菌株的x值与Y值相关关系显著。用改良的涂布平板法测定,苗菌敌对茄黄萎病菌孢子萌发有明显的抑制作用,病菌孢子在浓度为0.001～0.500 mg/mL药液中处理48 h后,兰州枯死菌株、普通菌株、天水菌株、白银菌株的孢子萌发相对抑制率分别为0.45 %～86.08 %、2.23 %～91.10 %、1.20 %～91.38 %、0.78 %～93.37 %。4菌株初生菌丝生长的速度均随药液浓度的增大而降低,菌丝出现畸形扭曲,不能正常生长发育,影响分生孢子梗的分化。

Measured toxicity of carbendazam-thiram on Verticillium albo-atrum of eggplant

There was obviously inhibited effect of carbendazam-thiram on eggplant 4 isolates of Verticillium albo-atrum hyphae growing by growing rate method measured , relative inhibition rate of 4 isolates hyphae growing was Lanzhou sphacelate isolate (Va1) 28.91 %～100 %, Lanzhou common isolate (Va2) 20.14 %～100%, Tianshui isolate (Va3) 19.30 %～100 % and Baiyin isolate (Va4) 33.36 %～100 % respectively. Carbendazam-thiram in PDA was 0.001 mg/mL～0.500 mg/mL cultured V. albo-atrum mycelium afler inoculum 72 h, toxicity regression equation was va1: y=2.372 7+1.304 7x, EC50=0.010 32 mg/mL; Va2: y=2.09514+ 1.4016x EC50=0.01182 mg/mL Va3: y=1.9099+1.4989x EC50=0.01152 mg /mL Va4 y=2.4536+ 1.324x EC50=0.008364 mg/mL The relationship between X and Y reached a significance correlativity. There was also obviously inhibited effect of carbendazam-thiram of V. albo-atrum on spores germination by improved smearing plate culture method, relative inhibition rate of V. albo-altrum spores germination was Va1: 0.45 %～86.08 %, Va2: 2.23 %～91.10 %, Va3: 1.20 %～91.38 %, Va4: 0.78 %～93.37 % respectively using 30 % carbendazam-thiram WP concentration range was 0.001～0.500 mg/mL tremented V. albo-altrum condium 48 h, and 4 isolates growing rate of primary hyphae were reduced with carbendazam-thiram concentration of increasing, hyphae showed spralism, mycelium could not grow normally and could not differentiated from normal conidiophore.