Abstract: To investigate some fundamental biological and ecological issues in the Rumex acetosa L. banker system, such as unclear patterns of occurrence of the Gastrophysa atrocyanea in the banker system, unclear consumption situation of the Arma custos on G. atrocyaneafield, and unclear settlement situation of A. custos in the R. acetosa L. storage system. The occurrence patterns of the G. atrocyanea in the banker system were investigated in four years. Moreover, laboratory experiments were carried out to study the predatory functional response of A. custos to G. atrocyanea. Additionally, a field study was conducted to examine the colonization pattern of the A. custos in the banker system. The results revealed that G. atrocyanea completed one generation per year in Huaxi district, Guiyang city. The overwintering adult began to appear in late February, while laying eggs in beginning March, and the larva appeared in early March with a high incidence period from late March to April beginning. The pupal stage began in early April, then the emergence peak reached in late April, and the adults gradually began to oversummering and overwintering after early May, which lasted for over 270 d. The predation function response suggested that the predation function of A. custos on G. atrocyanea conformed to Holling II model. The daily maximum theoretical predation rate was 8.850 prey, which was equivalent to the daily maximum observed predation 7 prey. Investigation showed that the colonization rate of the A. custos decreased with the density of prey G. atrocyanea decreased, and the retention time of A. custos was 30 d in the R. acetosa L. banker system. These results indicated that setting up an appropriate R. acetosa L. banker system could be one of the most effective measures to retain A. custos when the prey was scarce in spring.

Key words: edato, colonization of predator, Rumex acetosa L., Gastrophysa atrocyanea, biological control