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杂草对农作物有很大危害是众所周知的,确切知道不同情况下的草害程度对防治对策有现实的指导意义。目前各地都在进行这方面的试验,方法和准确性也异。本文介绍了野燕麦对小麦、青稞在青海省条件下的危害,其方法可供各地参考。同时对试验中所应用的数理统计是否合宜,也可供讨论。1.田间野燕麦发生密度对小麦、青稞产量损失之间有着极显著的回归关系。野燕麦穗数即花序数每增加1万穗/亩,小麦产量损失5.39斤、穗粒数减少0.15粒、千粒重降低0.102克,青稞产量损失3.5斤、穗粒数减少0.17粒、千粒重降低0.02克。2.小麦三叶期以前田间出苗的野燕麦危害最大,在野燕麦10万株/亩左右密度下,减产35.5%;小麦开始拔节以后出苗的野燕麦危害较小,造成减产8%以下。3.田间野燕麦密度越大,后期复盖阴闭越严重。野燕麦株数每亩16万株以上,复盖度90%以上,并导致小麦倒伏。4.据野燕麦危害损失,结合当前生产水平,对野燕麦发生的轻度危害田、中等危害田、严重危害田、控制田的划分指标和防除策略进行了探讨。
Weeds are very harmful to crops is well known, know exactly the extent of grass damage in different circumstances a practical guide to the prevention and treatment measures. At present, tests are being conducted in various fields all over the world, with different methods and accuracy. This article describes the wild oat on wheat, barley in Qinghai Province under the conditions of harm, the method for reference. At the same time, whether the mathematical statistics applied in the experiment are appropriate or not is also available for discussion. 1. Field density of wild oats on wheat, barley yield loss between very significant regression. The number of wild oats is the number of inflorescence increased by 1 million spike / acre, 5.39 kg loss of wheat yield, 0.15 grains reduced spikelets, grain weight decreased 0.102 grams, 3.5 kg yield loss of barley, grains reduced 0.17 grain, grain weight decreased 0.02 grams . Wild oat germinated in the field before the three-leaf stage of wheat was most harmful, yielding 35.5% reduction in the density of wild oats at the density of 100,000 plants / mu. Wild oat germinated after the wheat began to join was less harmful, resulting in a decrease of less than 8%. 3 field wild oats the greater the density, the more late cover cloudy closed more serious. Wild oats per mu more than 160,000 strains, covering more than 90%, and led to lodging of wheat. According to the harm loss of wild oats and the current production level, this paper discusses the slight damage fields, medium hazard fields, serious damage fields and control fields and the control strategies of wild oats.