摘要 : An attempt was made to develop a forewarning system for rice yellow stem borer, <i>Scirpophaga incertulas</i> infestation and outbreaks using pheromone traps containing (Z) 11-hexadecenal and (Z) 9-hexadecenal at 3:1. Field infest... 展开 An attempt was made to develop a forewarning system for rice yellow stem borer, <i>Scirpophaga incertulas</i> infestation and outbreaks using pheromone traps containing (Z) 11-hexadecenal and (Z) 9-hexadecenal at 3:1. Field infestation of <i>S. incertulas</i> was evaluated based on % occurrence of dead hearts and white ears. Each weather variable was assigned weight age based on their relative importance to stem borer initiation and spread. The economic threshold level of stem borer can be determined in terms of % occurrence of dead hearts and white ears or pheromone trap catches of moth to decide the timing of insecticide application. Pheromone trap catches was used to forewarn regarding their outbreaks on which a linear regression equation was developed for predicting insect infestation in advance. Based on three years data, the catching of moth in trap was commenced as early as 32 standard week (2nd week of August) with its peak during 37 standard week while incidence of dead heart started at 34 standard week (4th week of August) and reached the peak at 38 standard week. (3rd week of September). Accumulated growing degree days (AGDD) and accumulated helio thermal unit (AHTU) were ranged from 921.9-1203.1 degrees C & 1659.1-1967.8 degrees C and 5044.7-6539.9 & 8080.4-9180.8, respectively during initiation and peak period of moth catching. Damage by the was severe at a range of 1203.1-1967.8 degrees C AGDD and 6539.9-9180.8 AHTU. 收起