Life table data for Aphis gossypii Glover (Homoptera: Aphididae), an important pest in glasshouse cucumber crops, were studied at 20, 25 and 30 °C on two cucumber cultivars (Cucumis sativus L.) in controlled climate cabinets. The development time on the cucumber cv. ‘Sporu’ ranged from 4.8 days at 20 °C to 3.2 days at 30 °C. Immature mortality was approximately 20% and did not differ between temperatures. Most mortality occurred during the first instar. Reproduction periods did not differ among temperatures, but at 25 and 30 °C more nymphs were produced (65.9 and 69.8 nymphs/♀, respectively) than at 20 °C (59,9 nymphs/♀) because of a higher daily reproduction. Intrinsic rate of increase was greatest at 25 °C (rm = 0.556 day−1). At 20 and 30 °C the intrinsic rate of increase was 0.426 and 0.510, respectively. On cv. ‘Aramon’, the development time of A. gossypii was approximately 20% longer at all temperatures. Immature mortality did not differ between the two cultivars. The intrinsic rate of increase on cv. ‘Aramon’ was 15% smaller than on cv. ‘Sporu’. The use of cucumber cultivars partially resistant to aphids is discussed in relation to biological control of cotton aphid in glasshouses. Development time and immature mortality on leaves of the middle and upper leaf layer of glasshouse grown cucumber plants (cv. ‘Aramon’) were comparable to development in the controlled climate cabinets. On the lower leaves immature mortality was much higher (approximately 82%) than on leaves of the middle (24.0%) and upper leaf layer (24.5%). Reproduction was less on the lower leaf layer (45.9, 70.5 and 70.1 nymphs/♀ on leaves of the lower, middle and upper leaf layer, respectively). Aphids, successfully parasitized by Aphidius colemani Viereck (Hymenoptera: Braconidae) only reproduced when they were parasitized after the third instar. Fecundity was 0.1 to 0.9 and 10.5 to 13.3 nymphs/♀ for aphids parasitized in the fourth instar or as adults, respectively. Reproduction of aphids that were stung but survived the attack was lower than for aphids not stung. Average longevity of these aphids was equal to the longevity of aphids not stung by A. colemani.

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Results were indicated that the population fluctuation of Aphid craccivora kock. and the Thrips tabaci were higher during (2012-2013 season) than the second season (2013-2014). The statistical analysis of simple correlation and partial regression showed that a positive significant relationship between the daily mean of temperature and relative humidity and aphid A. craccivora population in the two successive seasons (2012-2013 and 2013-2014). The relationship between the predators Green lacewing Chrysoprla carnea (Steph), Hover fly Metasyrphus Corrollae and the pest population were negative significant. The partial regression significant were negative significant relation between C. carnea and the pest population while the partial regression cleared that a positive significant relationship between M. corollae with A. craccivora in both seasons. The simples correlation indicated that a positive significant relationship between each of the daily mean temperature and the relative humidity and Thrips tabaci while the partial regression coefficient and the relationship were negative in the two successive seasons. The relationship between the Green lacewing C. carnea and hover fly M. corrollae and Thrips tabaci were negative significant. The partial regression values were insignificant in (2012-2013) but positive significant in (2013-2014) seasons for C. carnea but the partial regression values of M. corrollae were significant in the two successive seasons.