MONITORING THE SEASONAL FLIGHT ACTIVITY OF STEM BORER MOTHS TO DETERMINE THE PROPER TIME FOR RELEASE TRICHOGRAMMA PARASITOID AT SUGARCANE FIELDS IN UPPER EGYPT

The seasonal flight activity of both sugarcane stem borer moths Sesamia cretica Led. (Noctuidae: Lepidoptera) and Chilo agamemnon Bles. (Pyralidae: Lepidoptera)were monitored with Robinson light trap for two successive years 2005/2006 & 2006/ 2007 at El-Mattana Agricultural Research Station, Qena Governorate, to determine the proper time for releasing the egg-parasitoid, Trichogramma evanescens West. for biological control program to the two mentioned borers without any application with chemical pesticides. The obtained results showed that, the moths of the greater sugarcane stem borer, S. cretica had a main period of seasonal activity extended from spring to early summer (April to June) and had another four small peaks of seasonal activity at sugarcane fields occurred in April, June, July, and October. The small sugarcane stem borer moth, C. agamemnon had two main periods of seasonal activity at sugarcane fields. The first period extended from spring to early summer (March to June) and the moths probably recorded two broods during this period, whereas the second period was relatively smaller and occurred during July. Results of statistical analysis showed that, the combined effect of the three main weather factors (mean of min. & max. temperatures and %R.H.) two weeks earlier were responsible on the changes in the seasonal flight activity of S. cretica moths for 51.6% and 66.7% explained variance for the 1st and 2nd year, respectively. Also, these factors were responsible on the changes in the seasonal flight activity of C. agamemnon moths for 57.7% and 44.1% explained variance for 1st and 2nd year, respectively. So, it could be recommended that, the egg-parasitoid, Trichogramma evanescens releasing program must be started at mid- April for autumn and spring plantations, while for the next ratoons after two months from harvest and continued biweekly intervals to the end of June.