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The potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is a noxious pest of the potato crop (Solanum tuberosum L.) in both field and storage in tropical and subtropical regions. Survival, development and reproduction of the potato tuberworm was compared on leaves and tubers of 10 common cultivated potato cultivars including Agria, Agata, Almera, Arinda, Baneba, Fiana, Marfona, Ramus, Satina, and Volvox at 25 +/- 1 degree C, 65 +/- 5% RH and a photoperiod of 14:10 (L:D) h. The results indicated that there were significant differences in the larval, pupal, and total developmental periods on the various potato cultivars. The total developmental periods varied from 26.6 (on Baneba) to 29.5 d (on Marfona),and ranged from 27.9 (on Marfona) to 30.5 d (on Agria) in the experiments on potato leaves and tubers, respectively. Immature survival rates were lowest on Agria (44.1%) and Marfona (40.6%) on potato leaves and tubers, respectively. The highest total fecundity was observed on Arinda (78.3 eggs) and Ramus (154.8 egg) on potato leaves and tubers, respectively. Significantly fewer eggs were laid on Marfona cultivar's leaves (44.6 eggs) and tubers (72.9 eggs) than any of the other tested potato cultivars. The female reproduction potential on potato leaves was significantly lower than on potato tubers. Cluster analysis of the biological parameters of P. operculella on different potato cultivars demonstrated that Marfona is partially resistant to potato tuberworm. The findings on the susceptibility or resistance of potato cultivars could be a fundamental component of integrated pest management programs for potato tuberworm.

The potato tuberworm, Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae), is a serious pest of the potato, Solanum tuberosum L. (Solanales: Solanaceae), in both fields and stores in tropical and subtropical regions. In the present study, the susceptibility of different potato cultivars to P. operculella was evaluated by measuring life table parameters. Tests were undertaken with leaves and tubers of 10 potato cultivars in the laboratory: Agria, Agata, Almera, Arinda, Baneba, Fiana, Marfona, Ramus, Satina, and Volvox. All parameters showed significant differences among tested cultivars. The longest mean generation times were observed on Marfona and Satina cultivars in the experiments on potato leaves and tubers, respectively. The lowest reproductive rate was observed on leaves and tubers of Marfona cultivar. Correspondingly, the lowest values of intrinsic rate of increase and the lowest finite rate of increase were also obtained on Marfona cultivar in tests on potato leaves and tubers. The highest intrinsic rate of incrase values were observed on Arinda and Baneba in the tests on leaves and tubers, respectively. The intrinsic rates of increase were significantly higher on potato leaves than on potato tubers. The lower performance of P. operculella on Marfona cultivar indicated that this cultivar is relatively less susceptible this pest and could be used in integrated pest management programs of P. operculella .

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