杂草发生规律西瓜田杂草的发生有两个高峰期,第一个高峰期在西瓜苗出土时,随着西瓜苗的出土,杂草也大量出土,这时出苗的杂草约占西瓜全生育期杂草总数的60%;第二个高峰期在西瓜蔓长70厘米左右时,早期未封住的杂草以及新出土的杂草与西瓜争光、争水、争肥,这个时期正值西瓜营养生长与生殖生长的关键期,杂草对西瓜大小、甜度产生直接影响,同时加重病毒病、炭疽病、蔓枯病等病害以及虫害的发生程度。 Weeds occur Watermelon weeds occur two peaks, the first peak in the watermelon seedlings unearthed, with the watermelon seedlings unearthed a large number of weeds were unearthed at this time about the emergence of weed watermelon all 60% of the total number of weeds in the growing period; the second peak in the watermelon about 70 cm long, the early seal of weeds and newly unearthed weeds and watermelon glory, fighting for water, fight fat, positive during this period Watermelon vegetative and reproductive growth of the critical period, weeds on watermelon size, sweetness have a direct impact, while increasing the virus disease, anthracnose, gummy blight and other diseases and the incidence of pests.