湖北省栗绛蚧发生规律及防治

栗绛蚧1a发生1代,以小若虫固定在1～2年生枝条上越冬,3月上旬越冬若虫出蛰,4月份蚧壳膨大变硬,雌成蚧4下旬至5月中旬为产卵期,平均卵量2500粒,卵孵化历期约6d,平均孵化率为97%;5月15日始见初孵若虫,5月下旬固定寄生,分泌蜡质覆盖体外,体极小,7月份蚧壳长到直径达2mm时,进入越夏、越冬.栗绛蚧的天敌有黑缘红瓢虫,内寄生蜂:花角跳小蜂,桑名花翅跳小蜂,中国花角跳小蜂,绛蚧细柄跳小蜂,绛蚧跳小蜂等8种,花角跳小蜂寄生于雄蚧,桑名花翅跳小蜂寄予生于雄蚧,也寄生于雌蚧,后3种寄生于雌蚧,1999年寄生于雄蚧的寄生率为14%,寄生雌蚧的寄生率为22.5%;自然天敌对栗绛蚧的控制作用显著.在防治板栗病虫时,增加施药次数、与施药时间不当,导致自然天敌对栗绛蚧控制能力减弱,加之栗绛蚧繁殖系数大,初孵若虫期降雨小或干旱等是栗绛蚧暴发的成因.栗绛蚧在轻、中度发生年,用药剂防治时,应在3月中、下旬施药,并注意挑治,以保护利用天敌的自然控制作用;40%速扑杀乳剂1500倍液防效显著.

Occurring Law and Prevention and Curing of Kermes nauai Kuwana in Hubei Province

There is only one generation of Kermes nauai Kuwana in a year Larva stays in the one or two years twigs to pass the winterDuring the first ten day period of March the larva comes outIn April the crust of it become bigger and harderThe first ten day of April and the second ten day of May is the spawning period of the female mature Kermes nauai Kuwana and the average amount of spawn is 2 500 The incubation will last for 6 daysThe rate of average incubation is 97%; On May 15th, the initial larva occursUntil the last ten day period of May the larva starts the stable parasitism, and secrete the wax to cover their bodies, which is very smallIn July, when their crust is about 2 mm in diameter, Kermes nauai Kuwana go into the summer, then in winterThe natural enemies of Kermes nauai Kuwana include Chilocorus rubidus Hope, Blastothris mys sp, Microterys kuwanae Ishii, Blastothrix chinensis Shi, Psilophrys tenuicomis Graham, Psilophrys may sp, etcBlastothrix chinensis Shi parasitizes male Kermes nauai Kuwana Microterys kuwanae Ishii parasitizes either male or female Kermes nauai Kuwana The latter three parasitize male Kermes nauai Kuwana In 1999 the rate of parasitizing male Kermes nauai Kuwana is 14% and the female Kermes nauai Kuwana′s is 225% The natural enemies have the notable effect in preventing Kermes nauai Kuwana When preventing and curing the inset pests on chestnuts, increasing the times of using the pesticide and using the pesticide in a inappropriate period may weaken the controlling Kermes nauai Kuwana, and further more, Kermes nauai Kuwana propagate in a large coefficient, and it is rainy lightly or it is dry during the initial period of larva All of above cause the Kermes nauai Kuwana widely occurrence During the light or middling occurring age of Kermes nauai Kuwana, if you use pesticide to prevent and cure them, it is better in the last twenty day period of March and pay attention to use selecting curing in order to protect and make use of the natural enemies′ controlling effectThe curing effect is notable in using 40% 