Achievements of Bio-control in India
Eighty two natural enemies (NEs) have been studied for utilization against crop pests and weeds, out of which sixty one NEs could be successfully multiplied in the laboratory, thirty seven species have been recovered from the field, two are providing partial control, three substantial control and four are providing economic benefits worth millions of rupees and twelve are augmented the same way as indigenous natural enemies. Eneyrtid nymphal parasitoid Leptomastix dactyopii introduced from West Indies in 1983 has successfully established on common mealy bug infesting citrus and many other crops in South India. Coccinellied predator Curtnus coeruleus (origin South America) introduced from Thailand in 1988 has colonized on subabul psyillid. Weevil Cyrtobagous salviniae(origin: Argentian) introduced in 1982 colonized on exotic water fern Salvinia molesta in 1983. The release of weevils has resulted in annual saving of Rs 681 lakhs on labour alone in Kuttanad district of kerala. Weevils Neochetina bruchi and N etchhorniae and hydrophilic mite Orthogalumna terebrantis (Origin Argentian) were introduced in 1982 and colonized in 1983 on stands of water hyacinth. Weevils have now established in 15 states. Saving on labour alone is Rs. 1120 per hectare of weed mat. Cephalonomia stephanoderis introduced in 1995-96 for the biological suppression of coffee berry borer, Hypothenemus hampei has established in several coffee growing areas.
Biosystematic studies on predatory coccinellids have been conducted and an annotated check list of more than 400 species prepared.A sort of classical biological control has been achieved by redistribution of Epiricanta melanoleuca, a parasitoid of Pyrilla perpusilla. Two species of Encarsia were found in 1999 – 2000 in Minicoy Island of Lakshdweep and have now established in the main land enabling suppression of the spiraling whitefly, Aleurodicus disperses. Breeding techniques for 48 host insects have been standardixed including rearing on semi-synthetic diet and the cost of production has been worked out improved laboratory techniques have been worked out for the multiplication of twenty six egg parasitoids, six egg-larval parasitoids, weed insects. An acrytic multi-cellular rearing unit was revised for rearing Helicoverpa armigera. Semi-synthetic diet developed for Chrysoperla carnea and Chellomenes sexmaculata.
Mass culturing methods for aphidophagous syrhids, predatory and ento coccids and several coccinellids developed.
Surveys for natural enemies of key crop pests have been conducted and the list of predators, parasitoids and pathogens complied.
Tritrophic relationship between natural enemies, their hosts and host plants has been detrmined. Oxidized and hydrolyzed L-tryptophan elecited greater egg laying by coccinellieds in cotton field. As a mass priming agent for the larvae of C. carnea tricosane increased the predatory potential Ahyposoter didymator and Tlenomous remus preferred to parasites Spodiptera litura larvae and eggs respectively, on castor and beet root. Spodiptera litura larvae and eggs respectively, on castor and beet root. Kairomones from scale extracts of H armigera and cotton and tomato crops and okra while Cotesia marginiventris preferred knoll-knol castor and cowpea and Eucelatoria bryani preferred cotton.
Suitable low temperatures for short term storage of trichogrammatids, Sticholotis madagassa, Eucelatoria bryani, Senometopia (= carcelia) iliota, Allorhogar pyralcphagus, Copidosoma koehleri, Hyposoter didymator, Cotesia marginiventris, Leptomasitix dactylopii, Strumipsis inferens, Paruchaetes psedoinsulta etc have been determined superior strains of Trichogramma chilonis have been determined for cotton sugareane and tomato crop. Endosulfan tolerant strain of Trichogramma chilonis have been determined for cotton sugarcane and tomato crop. Endosulfan tolerant strain of Trichogramma chilonis was developed for the first time and the technology transferred to a private company for large scale production. High temperature and multiple insecticide tolerant strains of T. chilonis being developed. Different pesticides have been screened against 37 natural enemies for indentifying relatively safer ones to used in BIPM. Primary cell nature from the embryos of Spodoptera litura has been established which will facilitate the multiplication of obligate microorganisms. Baculoviruses from several lepidopterous hosts were identified and cross infectivity studied. Physico chemical characters of NPVs of Spodoptera exigua and Galleria mellonella analyzed.
A wheat bran powder based formulation of Trichoderma harzianum (PDBCTH 10) was found very effective in controlling chckpen root rot and wilt (Rhizoctonia solani). A now cost effective medium (molasses-soy) was identified which resulted in maximum production of chlamydospores of T. harziamum. Pseudomonas putida (PDBCAB 19) and P. flucrescens (PDBCAB 2, DBCAB 29 and PDBCAB 30) were identified as potential antagonists of Botrytis cinera, Macrophomina phaseolina, Rhizoctonia solani and Fusarium oxysporum f sp. Cicer.
Efficient strains of entomophilic nematodes isolated and tested from soil samples throughout the country. In vitro mass production technique for entomophilies nematodes, Steinernema spp. And Heterphabidytis spp developed utilizing wout’s medium, Verticlillum chlamydosporium Psedomonas flourscen and Pasteuria penetrans were found effective in suppressing plant parasitic nematodes.
Hirsutella thonpsonii was found effective against coconut mite, Aceria qurreronis and developed as a formulation called “Mycohit”.
Egg parasitoids T. chilonis and Telenomus dignoides, larval parasitoids Cotesta flavipes, Glyptomorpha nicevillel and Isotima lavensls were found important for the control of sugarcane borers. Beauveria basstana, B. brongntatti and Metarhizium anisophliae were mass cultured and utilized effectively against sugarcane white grubs. T. chilonis has proved to be effectively against maize stem borer, Chilo partellus. BIPM modules developed for cotton pest control were found effective in Ludhiana, Coimbatore and Ananad. The module could increase yield, conserve naturally occurring biotic agents and increase the benefit as compared to insecticidal sprays. Intergration of Telenomus remus, Chrysoperla carnea, Bt, SINPV and neem seed kernel suspension was successful in the management of S. litura and tobacco.
BT and SINPV formed important components of BIPM in tobacco; BT and HaNPV were important components of BIPM of pod borer complex in pigeon pea and pod borer of chickpea.
Biocontrol based IPM module involving Trichogrammatid releases for the control of stem borer and leaf folder of rice were found better than routine insecticide schedules. The cost – benefit ratio for BIPM was 1:2.74 whereas for chemical control it was 1:1.52.
Apanteles taragamae, Bracon hebetor, Gonizus nephontidis, and Brachymeria nosatoi are the key Biocontrol agents on Opisina arenosella. Their inundative release coinciding the first release with the first appearance of the pest has proved effective. Orystes baculovirus has been highly successful in reducing the Oryctes rhinoceros popular in Kerala, at minicoy and Andrah – Lakshadweep and Andaman islands.
Release of Cryptolaemus motrouzieri was found to reduce the population of mealy bugs, Planococcus lilacinus and Maconellicoccus hirsuius. Eggs of pomegranate fruit borer, Deudorix isacrates were heavily parasites by three species of eggs parasitoids. Aphielinus mali and several cocconellid predators were found effective against apple wooly aphid. San Jose scale natural enemies, Encarsia perniciosi and Aphytis sp. were well established in Jammu and Kashmir and Himachal Pradesh.
Trichogrammatoidea bacitrae and BT were found effective against Plutella xylostella. Management of tomato fruit borer, H. armigera through release of T. pretiosum and HaNPV spray was found effective. Copidosoma koehleeri and Bt were found effective against potato tuber moth in country stores.
Significant impact of Neochetina eichhorniae, N. bruchi and Orthogalumna terebrantis against water hyacinth was seen in Assam, Maharashtra, Gujrat, Kerala and Punjab. Fusarium pallidoroseum was found suitable as a candidate for Parthenium control. Training programmes on mass production and demonstration of the impact of Trichogramma Cryptolaemus, Chrysoparia, HaNPV and SINFV have been conducted in many states.Sotiwares PDBC INFOBASE, giving information about bioagent producers and BIOCOT, giving information about Biocontrol measures for cotton pest developed.