ANNUAL REPORT - Department of Biotechnology

development of root knot nematode, Meloidogyne
incognita on tomato at TERI, New Delhi and PDBC,
Bangalore. Seven EPN isolates from the collected
from hills were identified as Heterorhabditis sp.
Pathogenicity of nematode isolates against Galleria
mellonella was studied and LC50 was calculated for
different EPN isolates. Progeny production of EPN
isolates in G. mellonella was studied and two best
isolates were selected. Application of EPN prior to M.
incognita infestation was found to reduce the root
knot nematode population and also reduce the
damage due to root knot infection on tomato plants.
At ICRI, Idukki, EPN are being identified for the
management of cardamom root grub. Thirty one local
EPN isolates were collected from the soil samples
and so far two local isolates viz. Heterorhabditis
indica (ICRI-18) and S.bicornutum (ICRI-35) have
been identified. Efficacy of three virulent isolates viz.
ICRI-18 (Heterorhabditis sp.), ICRI-90 (Steinernema
sp.) and ICRI-81 (Heterorhabditis sp.) were
confirmed against root grub by laboratory bio-assay.
Significant reduction of root grub has been observed
in the field conditions also and100% grub reduction
was observed in some of the field trials.
Genetic improvement of EPN for tolerance to
environment and enhanced efficacy against
Helicoverpa armigera, cotton bollworm, is being done
at CICR, Nagpur. One isolate each of H. indica and
S.riobrave was developed to tolerate high
temperatures. Both isolates could infect H. armigera
Bacterial symbiont developed into formulation
against sucking pests of cotton
DBT Annual Report 2006-07
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larvae at high temperature of 40 C and found to be
effective against other insect pests viz. Anomis flava,
Spodoptera litura, Pectinophora gossypiella, Sylepta
derrogata and Earias sp. at ten to fifteen infective
juveniles per host larva. A new bacterial formulation
was also developed from bacterial symbionts against
sucking pests of cotton and was found effective
under field conditions. This formulation was also
effective for control of Bracon sp.
At PDBC, Bangalore, genetically improved strain of
Trichogramma chilonis Ishii resistant to multiple
insecticide and high temperature has been
developed. The strain showed cross tolerance to
many other insecticides also. Genetic analysis of the
strain for tolerance to endosulfan, monocrotophos
and fenvalerate suggested that semi dominant and
recessive genes are responsible for tolerance.
Biochemical studies showed that difference in
esterase isoenzyme composition is due to the role of
esterases in insecticide resistant mechanism. Out of
forty RAPD primers tested, fourteen primers were
found useful in studying polymorphism. RT-PCR for
hsp (heat shock proteins) gave three bands of the
size 500bp, 400bp and 300bp.
At GBPUA&T, Pantnagar, also temperature and
insecticides tolerant strains of T.chilonis and
Chrysoperla are being developed . Native superior
strains of these species were mass multiplied in the
laboratory and subjected to selection pressure of
insecticides and temperature to develop their
tolerance. T.chilonis took seventy generations to
develop tolerance against ¼ of field dose of both
endosulfan and chlorpyriphos. Sixty two generations
against imidacloprid and sixty six generations
against cartap hydrochloride. T. chilonis and
Chrysoperla carnea have developed tolerance up to
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42 C temperature. C.carnea was reared at
incremental doses of all four insecticides and found
to have tolerance to the ¼ of the field dose of
insecticides.
At TNAU, Coimbatore a biopesticide formulation is
being developed for the management of major pests
and diseases of rice ecosystem. Four plant growth
promoting rhizobacteria (PGPR) strains of
Pseudomonas fluroescens viz. TNAU Pf-1, TDK-1,
Py-15 and P. putida producing antibiotics like
Diacetyl pholro glucinol (DAPG) and phenazine
chitanase and ACC deaminase were found to be