Abstract: To study the effect of rice cultivars on the oviposition,emergence, worm development and natural enemv parasition of caseworm and losses caused by the pest,observations have been made on 16 rice cultivars in Huanghai State Farm in Northern Jiangsu province,where caseworm gradually become more and more vi-olent since the changes in cultivation system.The pest lay more eggs and cause more serious damage on the rice cultivars with larger plant.So that,consideration of the pest should be taken into account in the selection of rice cultivars.

Key words: intercropping, Morus alba, Setaria italica, diurnal variation of photosynthesis.