EVALUATION OF DIFFERENT SPECIES OF TRICHOGRAMMA ON CHILLI FRUIT BORER HEUCOVERPA ARMIGERA (Hubner).
Loading...
Date
2001-08-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UNIVERSITY OF AGRICULTURAL SCIENCES GKVK BANGALORE
Abstract
Experiments were conducted to find out the parasilizatlon by five
Trichogranma spp on chilli fruit borer Helicoverpa armigera (Hubner) in
laboratory and greenhouse conditions. Along with some basic studios
on the effect of food on fecundity of the parasitoids, lifecycle, host aee
preferrence were also carried out in addition to tritrophic interaction
among chilli genotypes, T. chilonis and H. armigera and relative toxicilv
of recommended insecticides to chilli fruit borer against egg parasitoid."
Fecundity of the parasitoids developed on II. armigera eggs was
found significantly different among different parasitoids, T. chilonis
recorded high fecundity with food (10% honey) and without food. While
T. japonicum and T. achaeae recorded low fecundity/female with and
without food respectively. Life cycle of the parasitoid was longest
in T. achaeae (217.6 h) while T. chilonis took least period (1912h)
on H armigera. Fresh to two days old eggs of H. armigera were
equally acceptable by all the five parasitoids while three to four days
old eggs were less to least preferred.
Maximum per cent parasitization of chilli fruit borer under
laboratory and greenhouse conditions was accounted by T chilonis (61
& 39.93%) followed by T. pretiosum (51.52 & 31.08) and T.brasiliensis
(44.25 & 28.50%) respectively. Byadgi Kaddi and Byadgi dabbi were
found biocontrol friendly which recorded high parasitization while LCA-
312 and GPC-82 were found least acceptable to parasitoid T chiloiiis on
H. armigera eggs.
The insecticides dimethoate, phosphamidon, pliosalone and
carbaiyl were highly toxic to T. chilonis adults on 24 h after treatment
where as dicofol, monocrotophos and endosulfan were slightly less toxic
while neemark was safe to adults.
Neemark was found to be safe while endosulfan and dicofol were
relatively less toxic to immature stages of T. chilonis while carbaiyl was
the most toxic. Emergence of T. chilonis adults was signincanlly
reduced when insecticides were sprayed on host eggs before
parasitization. Longevity of T. chilonis adults that emerged from
insecticide treated host eggs were found to be adversely affected.
Description
Keywords
null