The Application Technology Of The Halosulfuron Ethyi Pretilachlor· Isoproturon 47%WP In Dry Direct-seeded Rice Field

This study focused on the cultivation methods of dry direct-seeded rice and the occurrence of weeds in Jiangsu Province.The application technology of the pre-emergency herbicide halosulfuron-methyl·pretilachlor·isoproturon 47%WP was studied in order to solve the problems which occurrence of weeds in dry direct-seeded rice field,The efficacy and safety of halosulfuron-methyl ·pretilachlor·isoproturon 47%WP were investigated through whole plant bioassay in greenhouse.Further,the safety of halosulfuron-methyl·pretilachlor-isoproturon 47%WP to rice under different conditions were evaluated through whole plant bioassay in greenhouse.Then,the safety and control effects of halosulfuron-methyl·pretilachlor·isoproturon 47%WP were investigatied in dry direct-seeded rice fields at different areas in Jiangsu Province through two years fields expteriments.Results obtained were listed as following:1.The safety of halosulfuron-methyl·pretilachlor·isoproturon 47%WP to rice.47%halosulfuron-methyl·pretilachlor·isoproturon WP at 900?4500 g/hm2 was safety to different varieties of rice(Nanjing 9108,Nanjing 11,Liangyou 669)when pre-emergence applied.The herbicide pre-emergence applied at 900 g/hm2 and 4500 g/hm2 did not negatively affect the plant height,tiller number,fresh weight of rice compared to the Water control when the rice at different leaf stage,cultured in different soil conditions,didn't cover the soil after sowing,artificial precipitation or ponding after treatments.2.The control effect of halosulfuron-methyl·pretilachlor·isoproturon 47%WP to weeds in rice.The pre-emergence application of halosulfuron-methyl·pretilachlor-isoproturon 47%WP at 900?2700 g/hm2 provided above 95%control effects on Echinochloa spp.,Leptochloa chinensis,Eclipta prostrata,Ammannia arenaria,and Cyperus difformis L.,Cyperus microiria Steud.The herbicide pre-emergence applied control effect was better than 2-3 leaf stage applied.3.The safety and efficacy of halosulfuron-methyl·pretilachlor·isoproturon47%WP in dry direct-seeded rice.The field experiment was carried out in 2014 and 2015.The herbicide pre-emergence applied at 1500?3000 g/hm2 did not negatively affect the plant height,tiller number,effective panicles,grain number per panicle,and estimated grain yield of rice compared to hand weeding.All treatments provided above 90%control effects on Echinochloa spp.,Leptochloa chinensis,Digitaria sanguinalis,Eclipta prostrata,Ammannia arenaria,and Cyperus spp.The herbicide pre-emergence applied at 1500?3000 g/hm2 provided less than 3%inhibition of the plant height and tiller number,and provided above 90%control effects when the rice at different leaf stage,cultured in different soil conditions,didn't cover the soil after sowing,artificial precipitation or ponding after treatments.4.The demonstrtion of halosulfuron-methyl pretilachlor isoproturon 47%WP in dry direct-seeded rice.The herbicide pre-emergence applied at 1800 g/hm2 provided 90%?100%stem control effects on weeds and were safe to rice in DSR of different ereas in Jiangsu Province.5.The application technology of halosulfuron-methyl· pretilachlor· isoproturon 47%WP in dry direct-seeded rice feild.47%halosulfuron-methyl·pretilachlor·isoproturon WP pre-emergence applied at the recommended doses,which were 1500?1800 g/hm2,could be safety to rice and effective control weeds in dry direct-seeded rice field.