4种除草剂对大豆根腐病菌的影响

选用90%乙草胺,25%氟磺氨草醚,70%嗪草酮,48%异噁草松4种除草剂对大豆根腐病菌（Fusarium oxysporumSchlecht.）的室内毒力、菌丝体干重和田间药效进行了测定。毒力测定结果表明：对菌丝生长抑制作用最高的是乙草胺、最低的是氟磺胺草醚,EC50分别为251.36 mg.L^-1和2 468.88 mg.L^-1。菌丝体干重的测定结果表明：4种除草剂对大豆根腐病菌的菌丝体均有抑制作用且随着剂量的升高而升高,除氟磺胺草醚外其他三种药剂在400 mg.L^-1时抑制率均在50%以上。田间试验结果表明：剂量为600 g.hm^-2的嗪草酮对大豆根腐病有抑制作用;各剂量的氟磺胺草醚在二叶期对大豆根腐病均有抑病作用。

Effects Test of Several Herbicides on Soybean Root Rot

4 kinds of 90% of acetochlor, 25% of fomeasafen, 70% of metribuzin,48% of clomazone are selected to determine the toxieity test,myeelium dry weight and control effect trial in field which were grew of Fusarium oxysporum Schleeht＇s myeelia. The toxicity test＇s results show that the highest function to inhibit the growth of mycelium was aeetochlor and fomesafen was the lowest inhibiting function, and their EC50 were 251.36 mg·L^-1 and 2 468.88 mg·L^-1. The mycelium dry weight test＇s results show that all of the 4 kinds of herbicides can produce the inhibiting function to the Fusarium oxysporum Sehlecht＇s myeelia, and the inhibiting function will increase with the increasing of the dosage. All herbicides＇ inhibiting rate was all 50% at the dosage of 400 mg·L^-1 exeept for fomesafen. Field trial indicated that metribuzin could inhibit soybean root rot at the dosage of 600 g·hm^-2. By the way, the fomesafen can also inhibit soybean root rot at any dosage in the two-leaf stage.