我场地处长江中下游江汉平原东南部,经济作物以棉花为主,每年种植2.5万亩左右。由于地势低洼加之春末夏初低温阴雨较多,棉花苗期病虫害每年发生较重,苗期病害常属偏重发生年份,往往造成缺苗断垄,甚至翻耕改种。害虫以小地老虎、蚜虫、红蜘蛛为主。据我站历史资料表明:1982年前,苗期病害死苗率最高达15.5%,小地老虎每亩虫量246头,断苗率最高达8%,棉蚜百株蚜 My field is located in the southeastern part of the Jianghan Plain in the middle and lower reaches of the Yangtze River. The cash crops are mainly cotton, with about 25,000 mu planted each year. Due to the low lying and the low temperatures in early spring and early summer, there is more rain and cold in the spring and early summer, and the annual occurrence of pests and diseases in the cotton seedlings is heavier. The diseases at the seedling stage tend to be year-by-year, often resulting in lack of seedlings and broken furrows. Pests to small tiger, aphids, red spider-based. According to the historical data of our station, before 1982, the rate of dead seedlings reached 15.5% at seedling stage, 246 pests per mu of small tigers, and the rate of cuttings was up to 8%. One hundred aphids