雀麦不同防除时间对小麦产量的影响
Study on the effect of different control time of grass Bromus japonicas on wheat yield

为明确山东省小麦田中禾本科杂草雀麦不同防除时间对小麦产量的影响，于2013—2015年连续在聊城市高唐县姜店村试验田中调查雀麦发生时间及数量，测定了不同雀麦防除时间的小麦产量情况。结果表明，该区小麦田在每年的3月1日—4月1日雀麦发生量最大，2013—2014年和2014—2015年度的平均密度分别为55.0茎/m2和297.0茎/m2。冬小麦田间雀麦的最佳除草时间在每年4月1日之前为宜；4月1日之后防除雀麦则造成小麦减产，严重时产量损失可达90.8%，甚至造成小麦绝产；综合2年度试验结果，雀麦危害造成小麦的产量损失能直接影响小麦的产量构成因素即小麦有效穗数，其次是千粒重，对穗粒数的影响较小。表明小麦田雀麦对小麦产量影响大小不仅与雀麦密度有关，也与雀麦防除时间密切相关。
To study the influence of different control time on Bromus japonicas in wheat yield in Shandong Province, the occurrence time and quantity of B. japonicas were investigated in 2013—2015, and the effects of different control time on the wheat yield were also determined. The results showed that the maximum occurrence time of B. japonicus in the area was from the beginning of March to the end of March. The average density of B. japonicus was 55.0 stem/m2 and 297.0 stem/m2 in 2013—2014 and 2014—2015, respectively. The best weed control time of B. japonicus in winter wheat area was before April 1st. Wheat yield loss was more than 90.8%, even more serious, when the weed control time later than April 1st. Moreover, yield loss of wheat was due to decrease the grains number of per spike. The results indicated that the influence of B. japonicus on wheat yield was closely related to weed density as well as its control time.