Bt food crop controversy is far from over

Debates over introducing Bt brinjal, the first genetically modified food crop in India, might have taken a different turn if the government had taken note of studies by one of its own R&D bodies, the Indian Council of Agricultural Research, showing that indigenous methods of controlling the notorious fruit and shoot borer can be as effective, cheaper and more environment friendly than using chemical pesticide.

Controlling damage by the fruit and shoot borer to brinjal -- the second-most important vegetable grown in India along with onion and tomato -- and reducing the use of harmful chemical pesticide have been cited as the main benefits of Bt brinjal.

Yet, two methods tested and cross-validated under ICAR auspices over a two- or three-year period suggest that there are low-cost indigenous alternatives to chemical pesticides with comparable yields and returns that could alter perspectives on the need for a genetically modified alternative.

These techniques, which are several decades old, involve either spraying the crop with tobacco-soaked water or applying a compost of cow dung and urine with seeds and leaves of the kochila tree. Yet, scientists who conducted the validation studies confirm that neither method is widely used any longer.

The findings appeared in a wider study that ICAR started in 2000. They are part of a wider "mission mode" project on collecting indigenous technical knowledge under the National Agriculture Technology Project.

The fruit and shoot borer is the single-largest cause of brinjal crop damage, estimated to cause yield losses of 60 to 70 per cent, often forcing consumers to buy insect-damaged and -infested fruit or those with high pesticide residues. The experiments under the NATP umbrella compared brinjal grown using indigenous and chemical pesticides.

The initial experiments with tobacco-soaked soap water were conducted in two villages in Nawada district in Bihar, the country's fourth-largest brinjal producer, by the departments of agronomy and extension education in Birsa Agricultural University, Ranchi.

The technique, which has been in use in this area for 30 years, involves soaking tobacco in water overnight, mixing it with soap or detergent and spraying a strong solution on the plants. One seedbed of brinjal was given five sprays of endosulphan, the most commonly used pesticide to control the fruit and shoot borer, and the other a similar number of sprays of tobacco-soaked water.

The results were tabulated on seven parameters that showed that the indigenous solution was as effective as the chemical one. The experiment also showed that the yield per hectare did not vary significantly: 354 quintal per hectare (q/h) for crops treated with tobacco-soaked water and 365 q/h for crops sprayed with endosulphan. Net returns were also roughly similar: Rs 135,906 and Rs 139,886 per hectare for crops sprayed with indigenous and chemical pesticide respectively.

Cross-validation studies in three other villages in the same district between 2002 and 2004 came to similar conclusions. "Both tobacco-soaked water and endosulphan are equally good at controlling fruit and shoot borer in brinjal and economically viable for production," the study said.

Significantly, however, the study also pointed out that, "The farmers informed that tobacco stalk was easily available at cheaper rate in the market (sic). It is eco-friendly and has no side effects either on soil or human health. In most of the houses, people use tobacco for chewing purpose and the waste product is utilised in controlling the insect pest in brinjal. Hence, (there was) no additional monetary involvement."

Dr K D Kokate, deputy director general (agricultural extension), ICAR, said technology validated by ICAR-affiliated universities are eligible to be disseminated through its extension network. He did not, however, reply to an email asking why this was not being done for these technologies.

Either way, as the Centre for Indian Knowledge Systems said in a memorandum to Jairam Ramesh, "The experts involved in the process (of evaluating Bt brinjal) have not given due consideration to indigenous technical knowledge that is available on this subject." Indeed, the multi-location field trials for Bt brinjal were compared against non-Bt counterparts sprayed with chemical pesticide simply because this is the method most widely used by farmers.

Those trials showed that the genetically modified version reported 98 per cent insect mortality in the shoots and 100 per cent in the fruit, significantly higher than the non-Bt versions. In addition, productivity and marketable yield were 30 and 24 per cent higher, respectively.

Some scientists opposing Bt brinjal, however, argue that technology that focused on killing insect pests is not sustainable because insects constantly evolve and eventually develop immunity to prophylactic measures, whether pesticide or GM varieties. "You have to consider that all insects came before humans and will outlive us. So when humans invent something effective against pests, it remains effective for a very short time," said Professor P C Kesavan of the M S Swaminathan Research Foundation.

He is among a growing band of scientists who argue for an integrated pest management system that combines multiple solutions to balance economic interests and ecological concerns. Many of these solutions are available in the Indian system.

Kesavan points, for instance, to a variety of brinjal grown in Karnataka that is immune to the fruit and shoot borer and suggests that it would be worth exploring the use of such genes "within the family" to develop pest-resistant varieties. MSSRF is also exploring using bio-pesticides such as cultivating a variety of wasps that are natural enemies of the fruit and shoot borer.