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柑桔红蜘蛛(Panonychus citri McG.),在国内分布于四川、云南、广东、广西、湖南、湖北、浙江、江西、福建等省的各柑桔产区。柑枯幼苗、大树普遍遭受为害,花、蕾、幼果、枝叶受害后,呈现灰白色斑点,严重时叶落枝枯,影响树势,限制着产量的提高,是当前柑桔上严重害虫之一。 在国外,苏联、美国等国家对此虫的研究资料较多,国内目前研究的资料较少,在防治上缺乏可靠的依据,往往不能控制其为害,以致猖獗成灾,由此,我们于1961—1963年,对此虫开展了有关发生规律、天敌及防治方法的研究。现将三年来研究的部分结果,初步整理于后。 材料和方法 工作地点 在本所和所属的试验农场进行。 发生情况调查 选生长一致的甜橙5株(20—30年生),在不防治的基础上,分别在二年生梢、一年生春梢、秋梢上,定期、定位(东、南、西、北、中等5个方位)。随机取400张叶片进行调查,记载叶片受害率和虫口,统计出受害指数:
Citrus red spiders (Panonychus citri McG.), Distributed in the country in Sichuan, Yunnan, Guangdong, Guangxi, Hunan, Hubei, Zhejiang, Jiangxi, Fujian and other provinces of the citrus producing areas. Citrus seedlings, trees generally suffer from damage, flowers, buds, young fruit, branches and leaves victims, showing gray spots, severe leaves fall dead, affecting the tree potential, limiting the yield increase is one of the current citrus pests . In foreign countries, the Soviet Union, the United States and other countries have more information on this pest, less research data in the country, and lack of reliable basis for prevention and control. They often can not control their harm and cause wild catastrophe. Therefore, in 1961 - In 1963, the worm carried out on the occurrence of laws, natural enemies and prevention methods. Now three years to study some of the results, initially sorted out. Materials and methods Workplaces are conducted at the site and the pilot farm to which they belong. Occurrence survey Five randomly selected sweet oranges (20-30 years old) were selected and randomly selected on the basis of non-prevention and control. The perennial shoots, annual spring shoots and autumn shoots were randomly selected and planted (east, south, west, north, Medium 5 directions). Randomly take 400 leaves for investigation, record leaf damage rate and insect population, statistics of the victim index: