Effects of temperature on development, survival, longevity, and fecundity of the Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) predator, Axinoscymnus cardilobus (Coleoptera: Coccinellidae)

Axinoscymnus cardilobus (Homoptera: Aleyrodidae) is an important predator of Bemisia tabaci (Coleoptera: Coccinellidae) that occurs in high population density of B. tabaci. Temperature among other factors is observed to play an important role in the development of arthropods. The effect of temperature on the development of A. cardilobus was studied at seven constant temperature regimes (14, 17, 20, 23, 26, 29, 32 degrees C). The results indicated that the duration of egg, larval and pupal stages were significantly influenced by increased temperature. The rate of development gradually increased with increase in temperature from 14 degrees C to 26 degrees C, but declined from 26 degrees C to 32 degrees C. The survival rates of different insect stages were stable at temperatures between 20 degrees C and 26 degrees C, but at extreme temperatures of 32 degrees C and 14 degrees C, a sharp decrease was evident. Ovipositional period of the female decreased when temperatures were increased from 17 degrees C to 32 degrees C. The highest fecundity of the female (225.7 eggs per female) was recorded at 23 degrees C. Life tables of A. cardilobus were constructed based on the experimental results at temperatures of 14-32 degrees C. The reproductive rate (R-0), the innate capacity for increase (r(m)) and the finite rate of increase (A) reached the maximum values at 23 degrees C, of 70.7, 0.059 and 1.062, respectively. The mean generation time (T) decreased with increased temperature from 17 degrees C to 32 degrees C, the highest and least values recorded at 17 degrees C and 32 degrees C were 112.7 and 38.7, respectively. These results offer valuable insight on the importation and establishment of A. cardilobus into new environments with diverse temperature regimes. (C) 2008 Elsevier Inc. All rights reserved.