关键词: 机直播稻, 乙氧磺隆, 杂草, 阔叶草, 防效, 水稻安全性

Abstract:

To develop the efficient and safe soil-applied herbicides in direct-seeded rice fields, a field test was conducted to evaluate the control efficiency of ethoxysulfuron on broadleaf weeds and sedge family weeds at different dates after sowing. The results showed that the germination and growth of broadleaf grass and sedge family weeds were effectively inhibited with weed control measure of synchronous seeding and spraying herbicides of ethoxysulfuron. And there was no negative influence on the rice seedling emergence rate after ethoxysulfuron treatment. However, the control effect on broadleaf grass decreased variedly when herbicides treatments containing of ethoxysulfuron were applied at 10 days or 15 days after sowing. All of poaceae weeds, sedge family weeds and broadleaf weed could be effectively controlled after treatment of 97.5 g a.i./hm² 0.65% penoxsulam·ethoxysulfuron controlled-release granules at 15 days after rice sowing, and the control efficiency of plant number reached over 90%. All these results suggested that ethoxysulfuron, as a soil-applied herbicide, should be applied earlier after rice sowing. But if the recommended application window was missed due to bad weather or other uncontrollable factors, the application of 97.5 g a.i./hm² 0.65% penoxsulam·ethoxysulfuron controlled-release granules or 112.5 g a.i./hm² 30% cyhalofop-butyl combined with 90 g a.i./hm² 30% penoxsulam·ethoxysulfuron treatment could also be a better choice to control most weeds in mechanized direct-seeded rice fields.

Key words: mechnized direct-seeded rice, ethoxysulfuron, weed, broadleaf grass, control efficiency, rice safety