USING DEGREE-DAYS MODEL TO DETERMINE THE OPTIMUM SPRAY TIMING FOR THECODLING MOTH CYDIA-POMONELLA (L) (LEP, OLETHREUTIDAE)

Successful spraying against Cydia pomonella (L.), the main pome fruits pest in Iraq orchards, depends on correct timing, which was determine d by the degree-days model or at intervals of 100 +/- 10 degree-days a fter the biofix. Sprays are most effective against the newly hatched l arvae before entry into the fruits. The optimum timing with laresban t reatments was determined to be at 200 degree-days after the biofix or after an average degree-days accumulation of 195 DD (SD = 59) and 298 DD (SD = 67) when daily degree-days calculated by the method of the si ne-wave.