Demographic Comparison of Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) Reared on Different Potato Cultivars

Potato Tuber Moth (PTM), Phthorimaea operculella (Zeller), is one of the most destructive pests of potatoes under field and storage conditions. Exploiting plant resistance may help control the pest in an eco-friendly manner. Therefore, the present study aimed to assess the resistance status of six common potato cultivars (Banba, Bellini, Draga, Marfona, Jelly, and Milva) under laboratory conditions (۲۵±۱°C, ۶۵±۵% RH and ۱۴:۱۰ (L: D) hours photoperiod). Life history and demographic parameters of P. operculella under laboratory conditions were analyzed based on the age-stage, two-sex life table theory, which could be appropriate indices in resistance and susceptibility evaluation of potato cultivars. Pre-adult development was slower on Marfona and faster on Banba (۱۹.۹۱ and ۲۱.۹۳ days, respectively) compared to the other cultivars. The longest oviposition days was found on Jelly (۸.۲۰ days), while the shortest (۵.۴۳ days) was on Bellini. The maximum values of r and λ were found on Marfona (r= ۰.۱۶۰ d-۱, λ= ۱.۱۷۳ d-۱), whereas the minimum values were recorded on Draga (r= ۰.۰۹۲ d-۱, λ= ۱.۰۹۶ d-۱). According to the findings of the present study, Draga was considered resistant and a less favorable host plant for the development and reproduction of PTM. These demographic data may be used to better understand the population dynamics of the pest on the six potato cultivars tested, thereby inevitably improve efficient pest management approaches for PTM in both organic and conventional production systems.

Keywords:

Host-plant resistance , Life table , Population dynamics , Potato tuber moth.