苗期水分管理对水稻分蘖及除草剂控草效应的影响

稻田除草剂大量及高频使用对农作物安全、土壤及水体环境构成了严重威胁，使得除草剂减量使用刻不容缓。水稻机插田药后长时间保水可显著抑制杂草，以此可减少除草剂用量，但长时间保水会导致水稻发育受限。盆栽试验表明，无论是否喷施除草剂30%苄嘧·丙草胺乳油，杂草发生随保水时长增加而减少，且喷施除草剂对杂草防除具显著效果。田间试验表明，稻田施用30%苄嘧·丙草胺乳油100 mL/667m~2后，药后保水7 d时的水稻分蘖及抑草的综合效应达到最佳。

Effects of water management at seedling stage on rice tiller and weed control of herbicides

The large amount and high-frequency use of herbicides in paddy fields pose a severe threat to crop safety, soil, and water environment, making it urgent to reduce the use of herbicides. Long-term water conservation can significantly inhibit weeds and bring down the quantity of herbicides, but will stunt the growth of rice. Pot experiment showed that the weed occurrence decreased with the increase of water retention time regardless of spraying herbicide bensulfuron-methyl·pretilachlor 30% EC. Spraying herbicide had significant effect on weed control. Field experiment showed that when bensulfuron-methyl· pretilachlor 30% EC was applied in paddy field at 100 mL/667m2 with holding the water retention for seven days, the comprehensive effect of rice tillering and weed suppression reached the highest.