Abstract
So far a number of studies have confirmed that organic farming and integrated pest management (IPM) enhance environmental conservation in terms of abundance of natural enemies, particularly in farm lands. In contrast, little is known for the corresponding effect in paddy fields. We carried out a factorial experiment, using azolla and paper mulch respectively as a bio-herbicide and a physical weeding measure, to examine whether these methods can enhance density of natural enemy, in paddy fields of Shiga prefecture. The results suggested that only weeding by azolla but not by paper mulch increased the density of natural enemies such as web spiders.
