干旱区生态环境知识资源中心

1. ELISA (enzyme-linked immunosorbant assay) was used to identify the arthropod predators of two common herbivores of a desert lupine: the aposematic plant bug Lopidea nigridea and the ant-mimetic plant bug Coquillettia insignis.

2. Despite the fact that the prey are closely related, the two antisera were sufficiently specific to distinguish between the antigen against which they were formed and the antigen of the other species: both antisera were 3 times as reactive against their homologous antigen as they were against their heterologous antigen.

3. In tests on gut contents of field-collected predators, ELISA results were generally consistent with laboratory no-choice data for the five most common arthropod species on lupine: there was a strong correlation between attack rates for each predator-prey pair as measured in the laboratory, and per cent positive reactions in ELISA as measured using field-collected predators. In particular, L.nigridea antiserum was shown to be significantly less reactive against the crab spider Xysticus montanensis when compared to C.insignis antiserum, paralleling results of laboratory no-choice experiments.

4. The usefulness of serological analysis as a tool for arthropod trophic link identification is discussed.