Effects of Temperature OnThe Development, Food Consumption and Utilization Parameters of the Last Two Larval Instars of Spodoptera littoralis (Boisd.)
Wedad E. Khafagi, Esmat M. Hegazi and Neama A. Aamer
Full Length Research Paper I Published July,2016
Journal of Agricultural Science and Food Technology
ABSTRACT
Spodoptera littoralis
(Boisd.) is one of the most destructive agricultural
lepidopteran pests in Egypt. About 90 to 95% of total
defoliation occurs during the last two larval instars. Sets
of caterpillars were raised on artificial diet from hatching
at one of four constant temperatures 15, 20, 25, or 30ºC.
The effect of temperature on the development and food
utilization during the last two larval stages were examined.
The duration of development of both penultimate and ultimate
instars significantly decreased as the temperature increased
from 15 to 30ºC. At each temperature, the duration of
penultimate instar was significantly shorter than the
ultimate ones. The development of both penultimate and
ultimate instars of S. littoralis larvae was
significantly fastest at 30ºC and slowest at 15ºC. The
insect had an extra moult at 20 (23.7%) and 25ºC (8.5%)
before pupation. The various rearing conditions affected the
different nutritional values. The data of nutritional
indices for the fifth and sixth instars of S.littoralis
are not generally consistent with each other.
Approximate digestibility (AD) values of the last two
instars were highest at 25ºC and lowest at 30ºC.So,
S.littoralis is better developed at 25°C, than any of
the other rearing temperature.
Key Words: Spodoptera littoralis, Constant
temperature, larval critical weight, Instar number, growth
and Nutritional parameters.
- Journal of Agricultural Science and Food Technology (JASFT)
- Journal of Medical and Biological Science Research (JMBSR)
- Journal of Scientific Research and Essays (JSRE)
- Research Journal of Educational Studies and Review (RJESR)
- Journal of Physical Science and Environmental Studies (JPSES)
- Research Journal of Engineering and Technology (RJET)
- Pearl Journal of Management, Social Science and Humanities (PJMSSH)