Comparison of the biological characteristics of the Plodia interpunctella Hubner (Lep., Pyralidae) on three date cultivars in laboratory conditions

The Indian meal moth, Plodia interpunctella (Hübner) (Lep., Pyralidae) is one of the serious pests of stored date in Iran and many parts of the world. Biology of this pest on three cultivars of date was studied. The experiments were conducted in laboratory conditions at temperature of 27±2 ºC, 45±5% relative humidity and a photoperiod of 16L:8D hours. Mean incubation period were estimated 3.10, 3.27 and 2.67 days respectively and mean larval developmental time were estimated 37.85, 43.01 and 48.0 days on Zahedi, Shahabi and Kabkab cultivars respectively. There was significant difference between mean larval developmental time and incubation period on different cultivars. Mean period of pupa on Zahedi, Shahabi and Kabkab cultivars were estimated 7.47, 8.01 and 7.19 days respectively. No significant difference was observed between mean period of pupa moths developed in Zahedi and Kabkab cultivars but pupal period was significantly different on Shahabi cultivars. Mean adult longevity on Zahedi, Shahabi and Kabkab cultivars were estimated 8.04, 8.37 and 7.72 days respectively. There was no significant difference between mean adult longevity on different cultivars of date.