BIOECOLOGY AND INFESTATION BEHAVIOUR OF THE RICE MEAL MOTH, Corcyra cephalonica STAINTON (LEPIDOPTERA: PYRALIDAE) ON FOXTAIL MILLET, Setaria italica (L.)
Loading...
Files
Date
2007-10-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Agricultural Sciences GKVK, Banglore
Abstract
The incubation period of C. cephalonica on Foxtail millet at 25 ±
and 71 ± 1.2 per cent relative humidity varied from 4 to 7 days (mean 4.66
days). Freshly hatched larva was creamy white coloured and passed
through six instars. The average duration of each larval instar was 4.13,
5.04, 3,73, 3.40, 5.46 and 9.69 days, respectively and total larval duration
took 31.26 days and pupal duration was 15.06 days. Developmental period
took 41 to 59 days (average 51.95 days). Full grown last instar larva
measured 11.02 mm in length. The mating period ranged from 60 to 130
minutes. The preovipositional period ranged from 1 to 2 days. Eggs were
laid singly or in groups of 3 to 5 eggs in rare cases. Fecundity ranged from
90 to 150 eggs; oviposition period lasted for 6 to 8 days. Adult females,
irrespective of food availabihty, lived longer than the males. The nature of
larval development did not differ on Foxtail millet. The larva started
forming grain cluster and started feeding inside the grain cluster. Finally
each larva makes 3 to 4 such grain cluster and mixed with broken grains
excreta and frass. The population stress study showed that a high release
of initial moth pairs (12 pairs) resulted in the early operation of crowding
effect and marked reduction in the population in subsequent generations.
In the studies on the influence of different grain properties on C.
cephalonica infestation, the broken grains and flour of Foxtail millet were
most preferred for growth and development. Among the different varieties
tested, Prasad variety offered maximum resistance to C. cephalonica
infestation, which was reflected in terms of lesser adult emergence from
this variety. Among varying grain moisture contents tested, 15.53 % was
most favourable for pest which reflected in terms of higher survival and
shorter developmental period. In host preference study, maize was the
most preferred host which showed higher moth emergence and weight loss
due to infestation.
Description
Keywords
null