Biology of potato tuber moth, Phthorimea operculella Zeller (Lep.: Gelechidae), on two potato cultivars

Potato tuber moth, Phthorimea operculella, is one of the most important pests of potato in Iran. Biology of the pest on two commercial potato cultivars, Sante and Arinda, was studied in Andimeshk, north of Khuzestan province, Iran. Samplings were weekly performed from two separate fields cultivated by two cultivars during two agricultural seasons (2013-2015). Adults and immatures monitoring were done by using sex pheromone trap and direct count respectively. Results showed that adults occurred with two months difference in the first and second agricultural seasons which is related to different means temperature in the two studied seasons. Significant correlation was observed between adult densities and weekly means temperature. First adults appeared on both cultivars in early February and December in the first and second agricultural seasons and peaked at the end of March, respectively. The peaks of egg number were observed at The end of March for the first and second agricultural seasons, respectively. First larvae were observed in early and mid of March in the first and second years. Larvae peaked at The end of March and mid of April for the first and second years, respectively. No considerable difference was observed among occurrence, peak and activity time of the developmental stages of potato tuberworm on The two tested cultivars.