| dc.description.abstract | The study was conducted to evaluate the parasitism efficacy, storage duration and
field release techniques of egg parasitoid, Trichogramma spp. in the IPM
laboratory and research field, Entomology Division, Bangladesh Agricultural
Research Institute, Gazipur during July-December 2013. The parasitism efficacy
of Trichogramma evanescens and T. chilonis on two host eggs, Sitotroga
cerealella (Angoumois grain moth) and Corcyra cephalonica (Rice moth) was
determined. There was no significant difference in the percent egg parasitism of T.
evanescens and T. chilonis on the host eggs, S. cerealella and C. cephalonica.
However, the highest parasitism was occurred in T. chilonis as compared with the
parasitism of T. evanescens. The highest number of adult emergence was recorded
from T. evanescens on the both host eggs compared to T. chilonis. Effect of
storage duration on the adult emergence of three parasitoid species T. evanescens,
T. chilonis and T. japonicum was evaluated from mass reared parasitized host
eggs and fresh host eggs of Sitotroga cerealella. Observation indicated that adult
emergence of three species was found higher in stored parasitized host eggs than
that of stored fresh host eggs. In all cases only from stored fresh host eggs
whereas, up to 20 days more than 90% adult emergence were recorded from
stored parasitized host eggs of T. evanescens. Stored parasitized host eggs gave
50% adult emergence up to 60 days. In contrast, in all cases from stored fresh host
eggs only up to 30 days more than 50% adult emergence were recorded. In both
condition, with the increase of storage period of parasitized eggs and fresh host
eggs, adult emergence of the three Trichogramma species reduced gradually. The
field release techniques of T. evanescens and T. chilonis on parasitizing the eggs
of S. cerealella, C. cephalonica and Leucinodes orbonalis (Brinjal shoot and fruit
borer) were assessed through paper strip method (release during pupation) and
adult release method in micro plot and open field condition. The results showed
that T. evanescens parasitized 75.5% of the host eggs (mean of three host eggs) in
micro plot through adult release method and 38.83% through paper strip method.
In contrast, T. chilonis parasitized 78.6% of the host eggs by adult release method
and 40.2% by paper strip method in micro plot condition. Both the species
exhibited a similar trend of parasitism in open field. It is therefore concluded that
the adult release of T. evanescens and T. chilonis was an effective technique of
attaining the maximum parasitism in both micro plot and open field condition. | en_US |
