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稗草是稻田中分布最广的重要杂草,稗草的著名特点是形态与稻苗酷似,因此剔除特别费工。它的种子量大,一株稗草的结实数平均在800—900粒以上。落入土中的种子,在水田中可保持四、五年不丧失发芽能力,因此田间一旦被稗革传染,士壤中的稗草种子往往逐年累增,难以清除。稗草的发育快,分蘖多,摄取肥料的能力强,所以对水稻的生长有很大影响。如果插秧时一兜稻秧中混入一株稗草,最后,这一兜中占绝对优势的,几乎全是稗草。据南北一些草害较重的地方估计,稗草造成的产量损失,平均在15—30%左右。实际上这还没有把间接损失估计在内。由于除稗特别
Barnyardgrass is the most widely distributed important weed in paddy fields. The famous feature of barnyardgrass is that its morphology resembles that of rice seedlings, so weeding out extra work. Its large amount of seeds, an average of more than 800-900 grains of barnyard grass. The seeds that fall into the soil can remain in the paddy fields for four or five years without losing their ability to germinate. Therefore, once the field is contaminated with barnyard grass, the seed of barnyardgrass in the soil tends to increase year by year and is difficult to remove. Barnyardgrass has fast development, more tillers and strong ability to ingest fertilizer, so it has great influence on the growth of rice. If a rice seedling seedlings mixed with a barnyardgrass, and finally, this pocket accounted for the absolute advantage, almost all of barnyardgrass. According to some places with heavy grass damage in the north and south, yield loss caused by barnyard grass is estimated at 15-30% on average. In fact this has not yet taken into account the indirect losses. Because except barnyard special