Biocontrol Progress in India

Once again, the Project Directorate of Biological Control (PDBC) based in Bangalore has been a hive of biocontrol activity. Major highlights of work in the last year¹ included the introduction of two parasitoids of the coffee berry borer (Hypothenemus hampei; CBB). Prorops nasuta and Phymastichus coffea were imported from Colombia and were established in the field, thus contributing two new country records.

The maintenance and supply of host insects and natural enemies from PDBC, together with the basic research that supports this, continues to be a priority activity to which much energy and expertise is devoted. Biosystematic studies were conducted on Indian predatory coccinellids, with Diomus recorded from India for the first time. Rearing techniques were standardized for a number of natural enemies, and biological and behavioural studies were conducted. Artificial diets were devised for host insects including Spodoptera litura and a number of natural enemies. More progress was made in the development of temperature- and multiple pesticide-resistant strains of trichogrammatid parasitoid wasps. Advances were also made on the production and use of insect viruses and fungi, fungal and bacterial antagonists, entomopathogenic nematodes, and fungal biocontrol agents of plant parasitic nematodes and weed pathogens.

On the information side, a CD version of the expert system BIORICE is now available, and a system for pest control in oilseeds and pulses is in preparation.

The success of PDBC in conducting necessary basic research, and developing this through lab studies and field trials to effective pest control solutions for farmers is illustrated by the many and varied field tests of modules they are developing for the biological management of pests in many crops. In the past year a vast number of field trials have been conducted in sugarcane, cotton, tobacco, pulses, rice, coconut, fruit and vegetable crops and potatoes in different states. A striking success this year has been the development of a biopesticide for coconut mite (Aceria guerreronis) [see 'Coconut mite in India: biopesticide breakthrough', General News, this issue]. Monitoring and evaluation of weed control agents against water hyacinth (Eichhornia crassipes) is also highlighted.

The Annual Report² provides details of these and other research efforts by PDBC in Bangalore and in its coordinating centres spread over different parts of India. The work at PDBC included biosystematic studies on Indian predatory Coccinellidae. Progress in rearing work included multiplication of Harmonia octomaculata on Ferrisia virgata and Aphis craccivora in the lab. It was also shown that higher parasitization rates of Helicoverpa armigera eggs by Trichogramma chilonis could be achieved with the aid of synomones (herbivore-induced plant chemicals). Artificial diets were syn-thesized for rearing Cheilomenes sexmaculata, Coccinella septempunctata, Chilocorus nigrita and Cryptolaemus montrouzieri. Endosulfan-resistant T. chilonis was utilized for developing a multiple-resistant pesticide strain. Fungal pathogens were isolated from Helicoverpa armigera, Plutella xylostella, and Chilo partellus. Nomuraea rileyi was cultured and a water dispersible powder formulation of Bacillus thuringiensis (Pusa Bt) developed and bioassayed. Trichoderma harzianum PDBCTH10 and T. viride PDBCTV23 as powder formulation were tested for control of fusarial wilt and Rhizoctonia wet root rot of chickpea. The entomopathogenic nematodes (EPNs) Steinernema carpocapsae, S. bicornutum and Heterorhabditis indica isolates were successfully used for control of Leucinodes orbonalis on brinjal [aubergine] in field trials. A talc-base formulation of EPN isolates showed a shelf-life of more than 3 months. The mycoherbicidal potential of Lasiodiplodia theobromae, Nigrospora oryzae, Phoma chrysanthemicola and P. eupyrena was tested against Parthenium hysterophorus.

In Punjab, a BIPM (biocontrol-based IPM) module proved effective for cotton pest control. In Gujarat, Andhra Pradesh, Tamil Nadu, Maharashtra and Punjab, cotton bud and boll damage and populations of sucking pests were lower with the BIPM module than with insecticide treatments. Bt products gave effective control in cotton in Gujarat. In Andhra Pradesh, the use of the EPN Steinernema carpocapsae was found superior to SlNPV against Spodoptera litura in tobacco nurseries. In Tamil Nadu, the pod borer (H. armigera) complex in pigeon pea was controlled with Bt-HaNPV application. In Andhra Pradesh, Heter-orhabditis indica sprays were successful against Helicoverpa armigera in pigeon pea. In Assam, Punjab, Gujarat and Tamil Nadu, integrated use of biocontrol agents and Bt was effective in reducing rice stem borer (Scirpophaga incertulas) popu-lations. BIPM modules at different crop stages were useful in management of rice stem borer and leaf folder (Cnaphalocrocis medinalis) in Kerala and Punjab. In Karnataka, as noted above, control of coconut mite was successfully achieved with the mycoacaricide formulation 'Mycohit' containing Hirsutella thompsonii. In Himachal Pradesh and Karnataka, fruit damage due to pomegranate fruit borer (Deudorix isocrates) was controlled with parasitoid (Trichogramma chilotraeae) releases. In Kerala and Assam, the weevils Neochetina eichhorniae, N. bruchi and the mite Orthogalumna terebrantis gave successful control of water hyacinth.

By: Dr. S. P. Singh

1Singh, S.P.; Rao, N.S.; Ramani, S.; Poorani, J. (eds) (2001) Research highlights - 2000-01. Bangalore, India; PDBC, 21 pp.

2Singh, S.P.; Rao, N.S.; Ramani, S.; Poorani, J. (eds) (2001) Annual Report 2000-01, Project Directorate of Biological Control, Bangalore. Bangalore, India; PDBC, 218 pp.

Copies can be obtained from:
Project Directorate of Biological Control (ICAR),
P.B. No. 2491, H. A. Farm Post,
Hebbal, Bellary Road,
Bangalore 560 024,
Karnataka, India
Email: pdblc@kar.nic.in / drspsingh@valise.com
Fax: +91 80 3411961