Biological Basis for Rearing Horned Gall Aphid, Schlechtendalia chinensis

The horned gall, one of the Chinese gallnuts, caused by Schlechtendalia chinensis is an important raw chemical material. But the yield of the gall is only 15~25 kg/ha in natural conditions. According to the results of the studies on the aphid’s biology, the main reasons why the yield is poor are as follows: the migration rate either in spring or in summer is very low; the mortality in overwintering period is very high; the sexuparae and the females produce a few offspring. So rate of increase of the aphid’s population is very low. On the basis of the above a great mass of sexuparae adults must be raised and reached the first host on which the gall is formed to get more galls by mass-cultivating the second hosts (mossess), mass-inoculating the aphids on the second hosts, selecting and creating a favorable environment for the growth and migration of sexuparae.