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1981～1990年连续10年在河南新乡棉花黄萎病重病田。定点、定株,种植同一品种,结果表明:年度间发病有较大差异。从发病轻重与气象因子关系分析,存在两种类型:一种为高温低湿轻病年,10年中有4年,7月30日平均病情指数(简称病指,下同)为15.39。第二种类型为低温高湿重病年,10年中也有4年,7月30日平均病指达33.44,为轻病年的2.17倍。7月份的气温是影响黄萎病发病强度的主要因子,若当年7月份连续两旬旬平均气温超过27℃,病指旬增长速度将会减慢,成为轻病年。在7月份气温较低的情况下,空气相对湿度与病指呈正相关,即7月份湿度超过80％,气温又较低,将成为重病年。
1981 to 1990 for 10 consecutive years in Xinxiang, Henan Province, Verticillium wilt disease. Fixed-point, Strain, planted the same species, the results show that: the incidence of the year there is a big difference. There are two types of relationship between severity of illness and meteorological factors: one is mild to hypothermia and mild to severe disease, 4 years in 10 years, and 15.39 on July 30, mean disease index (abbreviated as disease index, the same below). The second type of severe disease of low temperature and humidity, 10 years, there are 4 years, July 30 average disease index of 33.44, 2.17 times the light illness year. July temperature is the main factor affecting the incidence of Verticillium wilt. If the average temperature in July consecutive ten-day period exceeds 27 degrees Celsius, the growth rate of the index will slow down and become a mild disease year. Relatively low air temperature in July, the relative humidity of the air and the finger was positively correlated, that is, in July the humidity of more than 80%, the temperature is lower, will become seriously ill.