Temperature effect on development and reproduction of silverleaf whitefly (Homoptera: Aleyrodidae)

The development, survivorship, and reproduction of silverleaf whitefly, Bemisia argentifolii Bellows & Perring, on eggplant at 6 constant temperatures (15, 20, 25, 27, 30, and 35 degrees C) were studied. The development time from egg to adult varied from 105 d at 15 degrees C to 14 d at 30 degrees C. A common developmental threshold for all immature stages was estimated at 12.5 degrees C. A nonlinear biophysical model describing the relationship between development rate and temperature was constructed. Low- and high-temperature inhibitions of 15-18 degrees C and 30-35 degrees C, respectively, for development of immature stage were derived from the model. The survivorship from egg to adult was 89% at 25 degrees C; at 15 and 35 degrees C, the survival percentages were 40 and 37%, respectively. The average longevity of adult females ranged from 44 d at 20 degrees C to 10 d at 35 degrees C. The oviposition (eggs per female) of B. argentifolii varied from 324 at 20 degrees C to 22 at 35 degrees C. Life table parameters were determined at 5 constant temperatures (20, 25, 27, 30, and 35 degrees C). The intrinsic rates of natural increase (r(m)) for B. argentifolii at 25 and 27 degrees C were the highest. Jackknife estimates of r(m) varied from 0.192 at 25 and 27 degrees C to 0.073 at 35 degrees C. The mean generation times of population ranged from 46 d at 20 degrees C to 18 d at 30 degrees C. The adverse effects of high temperature (35 degrees C) were evidenced by prolonged development, shortened adult longevity and reduced fecundity. The optimal range of temperature for B. argentifolii population growth was 20-30 degrees C. The results of this study were compared with those reported for B. tabaci biotype B in Mississippi and B. tabaci biotype A in Arizona.