Plant Resistance to the Moth Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae) in Tomato Cultivars

The resistance of 11 tomato cultivars (Ps-6515, Berlina, Poolad, Petoprid-5, Zaman, Matin, Golsar, Sandokan-F1, Golshan-616, Sadeen-95 and Sadeen-21) to the tomato moth, Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae) was investigated under field conditions. A randomized complete block design was used with three replications. Data analysis indicated that there were significant differences (P < 0.05) among cultivars regarding leaflet damage, leaf damage, overall plant damage, number of mines per leaf, number of holes on the stem, and fruit. Our findings revealed that the cultivars Berlina, Golsar, Poolad, and Zaman were less suitable cultivars, suggesting that they are more resistant to the tomato moth than the other cultivars. The high density of leaf trichomes present in the cultivars Berlina, Zaman, and Golsar can be one of the possible causes of resistance to T. absoluta. Knowledge of the extent of susceptibility or resistance of cultivars to a pest on a crop is one of the fundamental components of integrated pest management (IPM) programs for any crop.

Application of the Trans-Theoretical Model (TTM) to Exercise Behavior among Female College Students

BACKGROUND

This study examined the applicability of trans-theoretical model (TTM) to understand exercise behavior among female college students in Hamadan University of Medical Sciences, Iran in 2007.

METHODS

A cross-sectional descriptive study was conducted. The dependent variables analyzed were exercise efficacy expectation, decisional balance (pros and cons). The independent variable was stage of exercise behavior change. Five hundred and ninety female students representing various disciplines on campus completed a valid and reliable questionnaire (r = 0.78) during regularly scheduled classes. More than seventy-three percent of sample were sedentary (pre-contemplation, contemplation, or preparation) whereas 24.6% were in the action stage (regularly active < 6 months) and 2.2% were in the maintenance stage (regularly active > 6 months).

RESULTS

All of the TTM constructs differed significantly across exercise stages. Students in pre-contemplation scored the lowest and those in maintenance stage scored highest on efficacy expectation and pros and reversed on cons.

CONCLUSION

Results supported the use of the entire TTM in examining exercise behavior among female college students.

Functional and numerical responses of Stethorus gilvifrons Mulsant feeding on strawberry spider mite, Tetranychus turkestani Ugarov and Nikolski

Laboratory experiments were conducted to measure the functional and numerical responses of Stethorus gilvifrons Mulsant feeding on Tetranychus turkestani Ugarov and Nikolski. Adult ladybirds were isolated singly for 24 h in 8 cm petri dishes with either 4, 8, 12, 24, 48 or 96 adult females of T. turkestani. Results showed a typical type 3 functional response, with up to 65.2 preys attacked when 96 preys were provided. The rate of attack and handling time were 0.0012 and 0.415 (days), respectively. The number of eggs deposited by the predator depended on the density of the prey; up to maximum of 223.6 eggs female(-1) at prey density of 96 spider mites were recorded. No eggs were laid at densities of 4 and 8 prey/arena.