对直播早稻田双穗雀稗危害损失测定结果表明 ,产量损失与双穗雀稗密度、总分枝数、鲜重之间存在极显著的线性相关。每平方米增加 1株 ,产量损失率平均提高 10 .2 8个百分点 ;分枝数每增加 1个 ,鲜重每增加 1g ,每亩产量损失分别为 0 .76kg和 0 .2 0kg。在产量损失构成中 ,以有效穗占主导地位 ,其次每穗实粒数 The results showed that there was a significant linear correlation between the yield loss and the density, total number of branches and fresh weight of Paspalum bicariatum. An increase of 1 per square meter, the yield loss rate increased by an average of 10.22 percentage points; for each additional branch 1, fresh weight for each additional 1g, yield loss per acre was 0.76kg and 0. 220kg. In the composition of the yield loss, the effective panicles dominated, followed by the actual number of grains per panicle