樟个木虱形态特征及生物学特性

樟个木虱Triozacamphorae是近年来上海地区香樟上发生的一种新害虫。作者对其形态和生物学特性进行了研究。樟个木虱在上海以 1年发生 2代为主 ,偶发 3代。樟个木虱以低龄若虫在叶片上越冬 ,3月下旬至 4月上旬越冬代羽化 ;第 1代开始于 3月下旬 ,羽化高峰在 6月份 ;第 2代开始于 5月下旬 ,并主要以该代若虫越冬 ;第 3代若虫偶发 ,开始于 7月上旬 ,以若虫越冬。樟个木虱第 1代若虫的平均发育历期为 5 0 72d,1～ 5龄若虫的历期分别为 :1 8 .3 1± 2 .2 1d ,1 4. 90± 9. 92d,6 .1 1± 2 . 2 0d,5 .80±3 . 61d ,5 60± 1 5 1d。成虫的寿命为 3～ 1 1d ,平均寿命为 6 41d。樟个木虱的产卵量为 3 9. 1粒 雌虫。2 4℃下 ,卵历期 5～ 7d不等 ,平均为 5. 3 4± 0 . 5 7d ,卵平均孵化率为 83 . 7%。樟个木虱低龄若虫中 3龄若虫最耐高温 ,其次为 2龄若虫 ,1龄若虫最不耐高温。

Morphology and biological characters of Trioza camphorae

Trioza camphorae Sasaki is one of the pests on the camphor tree Cinnamomum camphora, which has been found in Shanghai recently. The morphology and biological characters were studied. The results showed that this pest occurs two generations per year, and occasionally three generations. It overwinters on the back of the leaf during the stage of the young nymph. The adult of overwintered generation appears from the last ten-day of March to the first ten-day of April. The initial occurrence stage of the first generation begins from the last ten-day of March and it reaches eclosion peak period in June. The second generation begins from the last ten-day of May, and the nymphs of this generation is the main overwintered stage. Some nymphs of the second generation can grow into adult and generate the third generation. The developmental duration of nymph is 50.72 days, and the duration of 1～5 instars is 18.31±2.21 days, 14.90±9.92 days, 6.11±2.20 days, 5.80±3.61 days and 5.60±1.51 days, respectively. The longevity of adult is 3 days to 11 days with the average 6.41 days. The fecundity is 39.1 eggs per female. At 24℃, the developmental stage of the egg is 5.34 days. The hatchibility of egg is 83.7%. The sequence of the tolerance of the different instar nymph on the higher temperature was 3rd>2nd>1st instar nymph.