Source: SEAMEO BIOTROP's Research Grant | 2016
Abstract:
An experiment on the
calassical biological control of C.odorata
using its bioagent, C. connexa was
carried out at BIOTROP, West Java, in a confined area under the shade of oil
palm trees from March to November 2016. The experimental design was factorial, the
first factor was C. odorata shoot tips density consisting of 3 levels, i.e. , 5, 10
and 20 shoot/ cage, and the second
factor was with release and without release of 5 pairs of C.connexa imago to the caged C.odorata.
There were 6 treatment combinations, replicated 4x., and randomised completely. In
March 2016, 24 plastic pots of 5 lt
capacity were filled with local soil
fertilized with composted goat manure at 1:1 ratio, and planted with 3 cut stem
of C.odorata . In June, the potted C.odorata were selected and trimmed to have the required density
and put in a cage measuring 50 x 50 cm
with the height of 150 cm . The cages were made of wooden frame with plastic
net of1 x 1 mm mess covering the whole sides to prevent parasites from entering
the cage, and there were a total of 24 cages. In June 4, 5 pairs of C.connexa
imago were released to the apropriate
cages. The release of C.connexa imago
induced the production of higher vegetative shoot tips on higher initial shoot
tip density. The release also induced the production of galls,however the
reselase reduced the production of flower heads, especially after the second
generation of C.connexa. The release
of C.connexa require 2,5 months to
generate the second generation. In that period a considerable new vegetative
shoot tips were produced. It was suggested to release the imago at the ratio of
20: 5 or higher every 2-3 weeks for the first 2,5 months.