Research on Weed Control Technology for Shallot Field at Different Time

LI Xiujie; ZHI Qianqian; WANG Shouguo; SU Wangcang; WU Renhai; LU Chuantao; XUE Fei; XU Hongle

doi:10.15933/j.cnki.1004-3268.2017.11.015

Abstract：Through field experiment we studied the control effect of 7 herbicides (pendimethalin and so on) andmixtures on weeds during different periods in shallot field and their safety to shallot,in order to screen efficient and safe herbicides for preventing gramineous weeds and broad-leaved weeds.The experiment result showed that pendimethalin had better control effect on gramineous grasses,up to 100％,but had poor activity to broadleaf grasses in the shallot transplanting time before emergence of grasses by soil treatment.The control effects of acetochlor and s-metolachlor on weeds were both lower,in the range of 36.39％-40.75％.The mixed use of pendimethalin and oxyfluorfen or bromoxynil octanoate could achieve better control effect on the gramineous weeds and broad-leaved weeds.The control effect of pendimethalin and oxyfluorfen mixture with lower dose was the best on weeds with 68.28％,the promoting rate for shallot growth was 9.59％,and the yield-increase rate was 11.81％.When the weeds grew to 3-5 leaf stage in the shallot growing season,quizalofop-P-ethyl + oxyfluorfen with lower dose,and quizalofop-P-ethyl + bromoxynil octanoate + oxyfluorfen had the best control effect on both gramineous grasses and broadleaf grasses by spray,and the controlling rates on total grasses were 74.74％ and 76.52％ respectively.These treatments could cause a slight phytotoxicity to shallot,but had no bad effect on the late production,and the promoting rates for shallot growth were 1.29％ and 7.92％,the yield-increase rates were 88.96％ and 70.42％ respectively.Quizalofop-P-ethyl and the mixed use of quizalofop-P-ethyl and bromoxynil octanoate had poor control effect on broadleaf grasses.The mixed use of quizalofop-P-ethyl and bentazone had certain control effect on the whole weeds except Cucumis melo L.var.agrestis Naud.The control effect of these treatments on weeds was lower than 40％.Before grass emergence,it is recommended to use the mixture of 330 g/L pendimethalin EC 2 250 mL/ha + 24％ oxyfluorfen EC 300 mL/ha with soil treatment.When the weeds grew to 3-5 leaf stage,we recommend the mixture of 10％ quizalofop-P-ethyl EC 675 mL/ha + 24％ oxyfluorfen EC 900 mL/ha,and 10％ quizalofop-P-ethyl EC 675 mL/ha +30％ bromoxynil octanoate EC 1 200 mL/ha + 24％ oxyfluorfen EC 750 mL/ha with pray.These herbicides could control both gramineous grasses and broadleaf grasses in shallot fields effectively and safely.