不同耕作方式对夏播大豆田间杂草发生的影响

Effects of Different Tillage Methods on Weed Emergence in Summer Soybean Field

研究了夏播大豆田常规耕作和保护性耕作对田间杂草发生的影响。结果表明:夏播大豆田在翻耕、翻耕后覆盖小麦秸秆、免耕留茬和免耕后覆盖小麦秸秆的不同耕作方式与秸秆覆盖措施相结合的条件下,各处理田间杂草的发生情况有显著差异。大豆播种后7周,各处理的杂草出苗总数分别为260.80株/m2、133.87株/m2、319.56株/m2和41.78株/m2。秸秆覆盖是影响杂草发生量的决定性因素。大豆播种后8周,杂草生物量分别为1567.33 g/m2、397.93 g/m2、1842.17 g/m2和369.00g/m2。夏播大豆田杂草集中在播后3周内出苗,杂草出苗数占出苗总数的95%左右,因此对田间杂草的化学防治应该在大豆播种后第3周进行。

The effects of conventional tillage and conservation tillage on the weed emergence in summer soybean field were studied. The results showed that the weed occurrence had significant differences with the conventional tillage （CT）, conventional tillage with straw （CTS）, no-tillage （NT）, and no-tillage with straw （NTS） . With the four tillage methods, the weed emergence rate was 260. 80 seedlings per m^2, 133.87 seedlings per m^2 , 319.56 seedlings per m^2and 41.78 seedlings per m^2 7 weeks after sowing, respectively, and the weed biomass was 1567.33 g/m^2, 397.93 g/m^2, 1 842. 17 g/m^2 and 369.00 g/m^2 8 weeks after sowing, respectively. Straw mulching was the decisive factor affected the weed emergence rate. About 95% weeds emerged in 3 weeks after sowing in the summer soybean field, which was the suitable time to control weed.