Abstract:

The sweetpotato wein East and
reproduction and niorhilih .
growth and geographical
control strategies for different
,
. Systems Research. Intern
.?ox 1558, Lima 12, Peru.pendcnce: j.okony;?: p:ar.org
?(Ipomoea batatas
,cn the zEr: n’e of temperature on development
in using
potential population
knowiedge, e-requisite for developing pest
zones. The effect cf tenuperature on the development
of immature stages, reproduction and mortality of C brunneus was studied af six constant (15,20,
25, 30, 35 and 40°C and at fluctuating temperature range of 22.9 8.7°C. Results obtained
indicated that at 15°C and 40°C, there was no development and reproduction of C. brunneus. At
35°C, only 46% of eggs hatched after 1.78 0.20 days but the larvae from these eggs did not
pupate. Egg-laying was not possible at 15 °C, 35 °C and 40 °C. The developmental period from
egg to adultat 15 °C, 20 °C, 30 °C and 35 °C was 59.43 ± 2.17 days, 49.00 ± 0.93 days, 34.70 0.45
days and 28.67 0.46 days, respectively and tended to decrease signiGcantly with increasing
temperature. Similar trend was observed for larval and pupae development time. There was 100
% egg mortality at 15°C and 40 °C. Larval mortality was highest (46 %) at 35 °C and lowest (18
%) at 25°C. After emergence, adults had a pre-oviposition period that ranged from 5.73 ± 0.21
days at 30 °C to 16.17 ± 0.91 at 20°C. C. brunneus laid the highest number of eggs (93.67 10.54
eggs) at 30°C and least eggs 26.33 ± 2.84 eggs at 20°C. Based on these life table data, the optimal
temperature for C. brunneus population growth and development was noted to be 25°C.