Abstract:

Abstract: A sunflower cultivars, LD5009, was planted in ten different sowing dates (in five days interval from 1st May to 14th June) in three locations in Bayan nur to analysis the effect of sowing date on damage avoidance in Homoeosoma nebulellum Hübner. Results showed that the most damage of H.nebulellum occurred in Linhe district in west of Bayan nur. When sunflower sown from 20th May to 30th May, lower sunflower seed damage rate varied from 0.17% to 0.47%, and lower sunflower disc damage rate varied from 6.47% to 23.30%. The earlier the crop was sown, the more severely damage was reached, and the least damage was sown on 25th May. With delay of sowing date after 30th May, sunflower disc damage rate increased, but sunflower seed damage rate was lower.