Study On Weed Control In Xinjiang Bermudagrass Seed Field

Weeds seriously affected the yield and quality of Xinjiang Bermudagrass in the seed production course. In order to control weeds, we investigated the weed species and weed occurrence law, confirmed primary weed and mastered its biology characteristics, and study on the chemical control effects of weeds in the seed field of Xinjiang bermudagrass, where was seriously affected by weeds. The results as follows:(1) There were 61 species 17 families weeds in the Seed field of Xinjiang Bermudagrass, the primary weed were Setaria viridis, Echinochloa crusgalli, Amaranthus retroflexus, Sonchus brachyotus, Hibiscus trionum, Chenopodium album, Acroptilon repens and Convolvulus arvensis, each of their frequency was more than 50% and density beyond 4.25 unit/m2. They severely had an effect on growth, seed-yield and seed-quality of Bermudagrass.(2) Malcolmia Africana, Convolvulus arvensis, Acroptilon repens, Cephalanoplos segetum, Artemisia frigida, Lepidium apetapum, et al were primary weed in spring, which arrived the fastigium in middle-late of April; Setaria viridis, Echinochloa crusgalli, Amaranthus retroflexus, Sonchus brachyotus, Hibiscus trionum, Chenopodium album et al were primary weed in summer, which arrived the fastigium in middle-late of May.(3) Chenopodium album, Hibiscus trionum, Setaria viridis, Echinochloa crusgalli, Amaranthus retroflexus, Convolvulus arvensis, Polygonum aviculare et al were the primary weed in soil seed bank, which mainly distributed in 0-10cm depth soil. The total amount seed of soil weeds was 9180.83 individual plants pers square meter, and the weed seed total germination of every layer soil were under 20%, total energy were about 50%.(4) The fit herbicides of soil treatment was acetochlor 2.7kg/hm2 whose controlling effect on the annual weeds could reach more than 90% ,and using it on 10th April and 20th May. The fit herbicides for broad-leaf weed was 2,4-D bufylate and MCPA-Na which completely killed the broad-leaf weed, the optimal using amount was 2.7kg/hm2 and 5.25kg/hm2 separately. The fit herbicides for bristlegrass and barnyardgrass was 1.2kg/hm2 fluazifop-p-butyl, whose controlling effect were 80% and 80.65% separately.(5) Pre-emergency herbicides of soil treatment had no effect on the growth of Bermudagrass, when they was spread 20-40 day before planting Bermudagrass. Pre-emergency herbicides(trifluralin, acetochlor and Dulegold) and Post-emergence herbicides(2,4-D bufylate and MCPA- Na) had not harmed on established Bermudagrass lawn, but fluazifop-p-butyl and Jinchaoke had.