Dynamics of brown planthopper egg-parasitoid community in non-rice habitats

The community dynamics of egg parasitoids that could parasitize the brown planthopper in non rice habitats such as bunds and roadside vegetation were studied. They were found to fluctuate quantitatively dropping and rising during overwintering, and affected by rice harvesting during the fallow after the first season rice. The dynamics of the communities were positively related to the number of the hopper egg parasitoids and rice planthopper in rice field during the first season rice growth period. The number of the communities decreased after the second season rice transplanted,then fluctuated within a certain range,increased then fell down greatly before harvesting. The communities were also found to be affected by the strategy of pest control during both fallow and rice growing period. The number of parasitoids, the species richness, the community diversity and the evenness indices of the communities from IPM rice field were always superior to those communities from non IPM rice field.