春玉米田杂草防治关键期

Critical Period of Weed Control in Spring Maize Fields

为了明确春玉米田杂草防治关键期,2013年和2014年通过不同时间除草对春玉米产量影响的田间小区试验,对黑龙江省哈尔滨市春玉米田杂草防治关键期进行了研究。结果表明:田间杂草以稗草、藜、苘麻为主,发生密度在100株·m^(-2)。出苗后21d之前除草玉米产量与无草对照没有显著差异,出苗后28d除草玉米产量和无草对照差异显著,可造成较大的产量损失。根据试验结果,春玉米杂草防治关键期为玉米出苗后21~28d。为了将产量损失率控制在5%以内,最好在玉米出苗后21d之前对杂草进行防治。

In order to determine the critical period for weed control （CPWC） in spring maize fields, field trials of the effects of weeding at different times on the yield of spring maize were conducted in 2013 and 2014 near Harbin in Heilongjiang province. The results showed that the main species of the weed included Echinochloa crus-galli ,Chenopodium album and Abutilon theophrasti, weed density was found in 100 paints· m^-2. There was no significant difference in maize yield between weed-free and weeding 21 days after maize emergence. But there was significant difference in maize yield between wee＆free and weeding 28 days after maize emergence. So,the CPWC in spring maize fields was about 21 to 28 days fater maize emergence. Weed control was carried out before 21 days after maize emergence assured loss of maize yield less than 5%.