柿树蚧虫及其防治方法的研究

经调查，在石家庄市郊区柿园蚧虫有６种：柿绒蚧、柿真棉蚧、日本龟蜡蚧、角蜡蚧、草履蚧、桃树木坚蚧，其中前两者为优势种，柿真棉蚧为国内新纪录。其发生特点是数种混合发生，但以一种为主。对柿树物候和主要蚧虫的生活史观察表明：蚧虫的发生与柿树物候期有一定相关性，从而确定了灭虫的最有效时间是：柿绒蚧在柿树结果后、果膨大前（６月１０日前后）；柿真棉蚧在柿果膨大前后（６月中旬）；日本龟蜡蚧在果膨大以后（６月下旬）；草履蚧在柿树芽萌动时期（３月上旬）。控制柿树蚧虫的危害，仍应以化防为主，保护利用天敌为辅。用久效磷或氧乐果喷雾防治，虫口减退率在９４％以上，辅之以久效磷涂梢，防效可达１００％。

Study on Persimmon Scales and Its Control

According to the investigation recently made in the persimmon orchards in the suburbs of Shijiazhuang City,6 species of persimmon scales are found: Eriococcus kaki.Eupulrinaria citricola,Paraceroslegia japonica,Ceroplastes ceriferus,Drosicha cerpleata,Partheuolecanium persicae . Among them, E. kaki and E.citricala are dominant species,and the latter is newly recorded in China.Usually,it is very typical that the persimmons are attacked by one dominant species,mixing with another or other species. The persimmon phenology and the life cycle of the principal scales have been studied. It is clear that the appearance of the scale is related to the persimmon phenology. As for E. kaki ,the best control period is between the persimmon fruit bearings and the fruit expansion(around June 10);for E. citricala ,in the process of fruit expansion(around mid June);for P. japonica ,after fruit expansion(in the last ten das of June);for D. cerpleata, in the time of persimmon sproutings(in the first ten days of March). For the control of the persimmon scales,the chemical prevention plays an important role,while the utilization of the natural enemy may as well help. By spraying monocrotothos or omethoate,the scale population decreased by over 94%,and if monocrotothos is simultaneously applied on the top of the tree,the mortality of the scales can reach 100%.