Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

Host plants
Damage
4.1
Agrius convolvuli
1990). The mean development period at 25¡C in Japan was 21.2 days
(Setokuchi et al. 1985). In Egypt at 30¡C and 61% RH average
developmental periods were: larvae 14.4 days, prepupae 1.9 days and pupae
13 days (Awadallah et al. 1976). The moths often enter houses in the evening
and, when at rest, resemble pieces of bark. There are at least two generations
during summer, and winter is passed as a pupa.
An artificial diet containing powdered sweet potato leaf has been
developed (Kiguchi and Shimoda 1994). On this at 27¡C and with a day
length of 16 hours, A. convolvuli larvae moulted to the 5th instar 12 to 14
days after hatching, pupated at 21 to 26 days and adults emerged at 36 to 41
days. The 5th instar larvae grew to 8 cm in length and 11 to 12 g in weight
(Shimoda et al. 1994). Consumption of sweet potato leaves was greatest at
30¡C, the last instar eating 88% of the total dry weight (5 g) consumed
(Setokuchi et al. 1986).
The main commercial host is sweet potato ( Ipomoea batatas),
but larvae also
attack other Ipomoea species [e.g. I. pescapreae,
I. cairica,
I. indica
(morning glory) I. hederifolia,
(Moulds 1981)] and other Convolvulaceae
[e.g. Merremia dissecta;
bindweed, Convolvulus arvensis;
Awadallah et al.
1976; (Moulds 1981)]. Several pulses are attacked [e.g. wild mung, Vigna
vexillata (Govindan et al. 1989); moth bean, V. aconitifolia (Bhat et al.
1990); mung bean, V. radiata and urd bean, V. mungo (Shaw et al. 1989);
and also Phaseolus spp. (Nagarkatti 1973)]. A strain of moth bean (IPCMO
131) showed good resistance to attack (Bhat et al. 1990). In Papua New
Guinea taro is also recorded as a host (Smee 1965).
A. convolvuli larvae can defoliate sweet potato vines and, even when damage
is less severe, harvest is delayed, increasing the likelihood of major attack by
the sweet potato weevil, Cylas formicarius.
Defoliation of pulses results in
partial or complete crop failure.
Natural enemies
These are shown in Table 4.1.1.
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