| Summary: | 碩士 === 國立臺灣大學 === 昆蟲學研究所 === 89 === The silverleaf whitefly, Bemisia argentifolii Bellows & Perring, was reared on three tomato varieties under various constant temperatures. The nymphal body length and developmental period from egg to adult decreased with the increase of temperature from 20℃ to 32℃. The male at 3rd and 4th instars, were significantly shorter than that of the female. The highest mortality from egg to adult were obsered at 20℃. The developmental time from egg to adult decreased with the increase of temperature from 20℃ to 32℃. The low temperature thresholds for the development of egg, 1st, 2nd, 3rd, and 4th and instar nymphs on Asveg #6 tomato were12.7, 10.1, 4.4, 7.4, and 10.8℃, respectively. Also on Asveg #6 tomato, the effective accumulated temperatures of egg, 1st, 2nd, 3rd, and 4th instar nymphs were 94.2, 72.7, 52.0, 49.5, and 102.3 day-degrees, respectively. With a total of 360.6 day-dgrees required for the development from egg to adult. The low temperature thresholds for the development of egg, 1st, 2nd, 3rd, and 4th and instar nymphs on Santa tomato were12.3, 9.9, 6.8, 11.7, and 12.0℃, respectively. Also on Santa tomato, the effective accumulated temperatures of egg, 1st, 2nd, 3rd, and 4th instar nymphs were 95.0, 72.6, 48.5, 37.2, and 99.0 day-degrees, respectively. With a total of 384.0 day-dgrees required for the development from egg to adult. The low temperature thresholds for the development of egg, 1st, 2nd, 3rd, and 4th and instar nymphs on Chiquita tomato were13.1, 10.6, 12.1, 13.7, and 11.8℃, respectively. Also on Chiquita tomato, the effective accumulated temperatures of egg, 1st, 2nd, 3rd, and 4th instar nymphs were 92.2, 69.0, 34.2, 32.8, and 93.1 day-degrees, respectively. With a total of 323.0 day-dgrees required for the development from egg to adult. The hight longevity reared at 20℃ on Asveg #6, Santa, and Chiquita tomatoes was 9.4, 11.1, and 11.3 days, respectively. The population parameters of intrinsic rate of natural increase( rm), net reproductive rate(), and finite rate of increase(λ) reared on Asveg #6 and Santa tomatoes were increased with the increase of temperatures from 20℃ to 32℃. When reared on Asveg #6 and Santa tomatoes as 32℃, the highest intrinsic rate of natural increase was 0.0946 and 0.0906, the R0 was 9.17 and 9.56, and λ was 1.10 and 1.09, respectively. The mean generation time (T) was 24.8 and 25.4 days, and doubling time was 7.33 days and 7.65 days, respectively. The highest of natural increase was 0.0593, the R0 was 8.76, λ was 1.06, the mean generation time was 27.1 days, and doubling time was 8.37 days when reared on Chiquita tomato at 28℃.
The population densities of B. argentifolii , when reared on Asveg #6, Santa, and Chiquita potted tomatoes in an open space at National Taiwan University from July to September, 2000, were no significantly different. The different population densities of B. argentifolii, when reared on potted Asveg #6 tomatoes in an open space at National Taiwan University from September to October 2000, the the yield loss of harvested fruit was positively correlated with the population densities.
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