据调查,目前上海市郊区水稻空秕率一般约为20%左右,严重的超过30%,特别是后季稻“不沉头”所造成的损失更大。水稻空秕率上升的原因是多方面的。三熟制早稻除抽穗期遇到阴雨会发生空秕粒以外,从栽培技术上看,主要是水肥管理不当,前期发不起,中期发过头,或者是“轰”过了头,造成“一路黑”,都会引起“黑里莠”,空秕率显著增加。这种情况尤以秧田稻和油菜茬的中晚熟 According to the survey, at present, the empty rate of paddy rice in the suburbs of Shanghai is generally about 20%, with a serious loss of more than 30%, especially for the non-decapitation of the latter crop. The reasons for the increase in the rate of rice vacancies are many. In addition to headwaters of three-crop early rice encounter cloudy rain will occur outside the empty grain, from the cultivation point of view, mainly improper management of water and fertilizer, can not afford the previous period, over the middle period, or “boom” too far, resulting in “all the way Black ”will cause“ black and white ”, empty rate significantly increased. This situation, especially in the late rice and rape crop stubble