Annual diversities changes of pests that caught on the light trap in relationship with pests community in the rice crop

摘要

Research of annual diversities changes of pests that caught in the light trap in relationship with the pest’s community in the rice crop was carried out at the Sukamandi Research Station of Indonesian Center for Rice Research (ICRR) from 2000 to 2013. The results showed that the annual abundance of yellow stem borer (YSB), brown planthopper (BPH) and rice black bug (RBB) on the light trap were always high compared to the other rice pests. Abundance of BPH and YSB on the light trap had signaled high population of both pests in the rice crop, this is due to the flights of both pest originated from the outbreak pests area. Abundance of RBB on the light trap did not signaled of high RBB pest populations in the rice crop, because although the populations RBB the highest that caught in the light trap did not caused outbreak in the rice crops. In accordance with the passage of time from 2000 to 2013, the diversity index of pests and natural enemies decreased from moderate to low diversity, and the evenness index declined from balanced community stability to the distressed communities. Similarities index of insects community that caught in the light trap did not increased, due to increasing of rarity of species and the other hand species richness declined. Instability of the community that caught in the light trap was signaled by low diversity index, evenness index declined, high of species rarity, low of species richness as a consequently of pests explosion in the rice field.