角倍蚜干母分批上树对虫瘿数量和分布的影响

对角倍蚜分批上树及接种方法对虫瘿数量和分布的影响进行了研究,结果表明:(1)迁飞接种(同批上树)时,单株虫瘿数为15.65个,而迁飞加挂袋(分批上树-A)及挂袋2次(分批上树-B)时,单株虫瘿数分别为48.39个和161.84个,增加了2.09倍和9.34倍;同时单叶虫瘿数也从1.69个增加到2.77个和3.42个;单株有虫瘿复叶数从8.70片增加到17.87片和46.00片;有虫瘿枝条率从21.65%增加到59.74%和91.58%。(2)迁飞接种时,虫瘿分布于当年生枝条第1~7片复叶,其中1~5片复叶为虫瘿主要分布叶片;迁飞加挂袋及挂袋2次时,虫瘿分布于当年生枝条的第1~8片及第1~11片复叶,其中第3~6片复叶为虫瘿主要分布叶片。(3)无论是干母同批上树还是分批上树,单叶虫瘿数均以1~3个为主,虽然分批上树时单叶平均虫瘿数从1.23个增加到1.47个和2.53个,但仍然低于单叶最适虫瘿数5~6个,对虫瘿的大小和生长没有不良影响。综上所述,干母分批上树可以显著增加角倍蚜虫瘿数量,提高虫瘿的分散度,充分发挥盐肤木形成虫瘿的潜力。

Improved Methods to Increase Gall Density and Scatter Gall Distribution for the Horned Gall Aphid Schlechtendalia chinensis

The Chinese horned gall aphid, Schlectendalia chinensis, is a major species of Chinese gallnut aphids. It produces horned galls that are economically important because of their medical and chemical properties, chiefly tannic acid. S. chinensis has six forms in its life cycle. Only one of these six forms, the fundatrix, is feeding on leaves and triggering the formation of a gall on its host tree, Rhus chinensis. The authors developed three different approaches in order to maximize the gall formation on R. chinensis by a combination of moving the winter host moss in close vicinity of the Rhus tree and/or hanging bags containing populations of aphids to the tree trunk. The results showed that the gall number per tree was about 10-fold higher than that of the controls in conditions where two bags containing aphid population of different age were provided to the tree trunk. Further, it was found that the number of leaves forming a gall increased up to 5-fold per tree and similarly, the authors measured a 4-fold increase in the percentage branches that harbor galls. Detailed analysis of how galls are distributed demonstrated that while controls formed galls on the first seven compound leaves, optimized conditions extend the production of galls to the first eleven compound leaves. Finally, the gall number per leaf also increased by various approaches. For instance, the percentage of leaves forming just one gall reduced by half compared to the controls, while the leaves containing 4 or more galls increased from 5% to >30% when providing two bags containing aphid population of different age.