大麻槿田使用苗后除草剂安全性评估及防效调查

Control Effect and Selectivity of Post-Emergent Herbicides on Weeds in Fields of Hibiscus cannabinus

为筛选出大麻槿田安全高效的除草剂,调查480 g/L灭草松水剂(AS)、10%乙羧氟草醚乳油(EC)、25%氟磺胺草醚AS、8.8%精喹禾灵EC、12.5%烯禾啶EC和120 g/L烯草酮EC等6种苗后茎叶除草剂对大麻槿畸形苗率的影响,并通过皮干重、株高、茎粗和鲜重评价其对大麻槿的安全性,研究这6种除草剂对大麻槿田杂草的株防效和鲜重防效。结果表明:6种茎叶处理除草剂中480 g/L灭草松AS和120 g/L烯草酮EC安全性较好,其处理过的大麻槿皮干重略低于清水对照。480 g/L灭草松AS 1.5 kg/hm^(2)处理的大麻槿畸形苗率为1.33%,药后40 d对阔叶杂草的鲜重防效为81.21%,株防效为80.53%;120 g/L烯草酮EC 0.525 kg/hm^(2)处理的大麻槿畸形苗率为0,药后40 d对禾草的鲜重防效80.68%,株防效80.94%;10%乙羧氟草醚EC和25%氟磺胺草醚AS对大麻槿安全性较差,大麻槿皮干重较低,畸形苗率显著高于480 g/L灭草松AS;施用8.8%精喹禾灵EC和12.5%烯禾啶EC 40 d对禾草的鲜重防效和株防效显著低于120 g/L烯草酮EC。大麻槿生长后,防除阔叶杂草宜选用480 g/L灭草松AS,防除禾草宜选用120 g/L烯草酮EC。

This study aimed to screen safe and effective post-emergence herbicides in fields of Hibiscus cannabinus.We investigated the influence of six post-herbicides on the rate of abnormal seedlings,estimated the selectivity of six post-herbicides via dray weight of H.cannabinus bast,plant height,stem thick and fresh weight of H.cannabinus,and explored plant control effect and fresh weight control effect of weeds.And the six post-herbicides were bentazone 480 g/L AS,fluoroglycofen-ethyl 10%EC,fomesafen 25%AS,quizalofop-ethyl 8.8%EC,sethoxydim 12.5%EC and clethodim 120 g/L EC in this study.The results showed that the selectivity of bentazone 480 g/L AS and clethodim 120 g/L EC presented excellent.The dry weight of H.cannabinus applied bentazone 480 g/L AS and clethodim 120 g/L EC were slightly lower than that applied the water control.The malformed seedling rate of H.cannabinus applied bentazone 480 g/L AS at 1.5 kg/hm^(2) was 1.33%.After 40 days,the control effect on fresh weight of broad-leaved weed was 81.21%,and the control effect on plant was 80.53%.The malformed seedling rate of H.cannabinus applied clethodim 120 g/L EC at 0.525 kg/hm^(2) was 0.After 40 days,control effect on fresh weight of grassy weed was 80.68%,and control effect on plant was 80.94%.Fluoroglycofen-ethyl 10%EC and fomesafen 25%AS had non-selectivity and lower dry weight of H.cannabinus.Malformed seedling rate was significantly higher than that of mirabilin 480 g/L AS.After 40 days,control effect on fresh weight and plant of the Gramineae applied quizalofop-P-ethyl 8.8%EC and fenpropafenone 12.5%EC were significantly lower than that of enoxazone 120 g/L EC.On the growth of H.cannabinus,bentazone 480 g/L AS is suitable to control broad-leaved weeds,while clethodim 120 g/L EC is suitable to control grassy weeds.