ngin - Norfolk Genetic Information Network

20 April 2002


India's recent commercial approval of the growing of Bt cotton, granted by its Genetic Engineering Approval Committee, has been surrounded by a massive amount of hype centering on claims that Bt cotton can deliver phenomenal results for farmers.
Indian Government advisor, CS Prakash, for instance, was reported as saying that even though the Bt seed might be more expensive due to patent protection, the value generated from using Bt cotton seed (in  terms of savings in labour and pesticide costs and improved productivity) far outstripped the cost. [Commercial Seeds Set To Take Root: Expert]
Similarly, India's Science and Technology Minister Murli Manohar Joshi claimed that the science showed that "use of Bt cotton eliminated the use of pesticides" and so delivered huge savings to farmers. [Govt to go by scientists on GM cotton: Joshi Times of India , MARCH 25, 2002]
The article below, however, from The Financial Express, India's leading business paper, paints quite a different picture.
Its account of Bt cotton performance appears to draw on details of a leaked copy of the very report from the Indian Council of Agricultural Research which underlay the GEAC's commercial approval and claims such as those of India's Science and Technology Minister that Bt cotton eliminates pesticide use.
"Bt Cotton Belies Promises: Research" is the telling headline.


Bt Cotton Belies Promises: Research
Ashok B Sharma, The Financial Express, April 20 2002
New Delhi, April 19: The final evaluation report of the Central Institute for Cotton Research (CICR) on Bt cotton field trials shows that these varieties, developed by Monsanto and marketed by Mahyco in India, are still susceptible to jassids, aphids and sucking pests and several crop diseases.
The Indian Council of Agricultural Research (ICAR) was asked by the Genetic Engineering Approval Committee (GEAC) to conduct co-ordinated field trials for Mech 12, Mech 162 and Mech 184 Bt cotton seeds in Central and Southern India. ICAR entrusted this work to its organisation, CICR. This organisation submitted its report about a month before GEAC took the decision to approve these varieties for commercial cultivation. The CICR study was, however, limited to agronomic evaluation, plant breeding evaluation and pest control. It did not study the impact on health and environment.
The field trials for assessing the efficacy of Bt cotton was taken up in comparison with the corresponding non-Bt hybrids and local and national check varieties, namely NHH 44.
The report stated that jassid population was higher in Bt and non-Bt Mech hybrids compared to check hybrids. Mech 12 was found more susceptible to jassids at all locations. In south zone, there were no significant differences in the incidence of sucking pests on Bt, non-Bt and check hybrids. Besides, seed treatment with Imidacloprid, the Bt cotton hybrids need two sprays in the central zone and three to four sprays in the south zone for controlling the sucking pests. Similarly, the non-Bt and check hybrids require three to four sprays both in the central and south zones. Among Bt hybrids, only Mech 12 Bt requires more number of sprays for sucking pests.
The report, further, stated that in central zone, Bt Mech 12 showed significant reduction in plant height due to its susceptibility to sucking pests. Higher fertiliser levels led to marginal improvement in plant height. Bt Mech 12 should be cultivated under assured soil moisture conditions. The field trials at Khandwa showed that aphid population was significant on Bt cotton except for the Mech 184 variety.
However, Bt hybrids exhibited excellent tolerance to bollworm, particularly Helicoverpa and Earias besides reasonable tolerance to pink bollworm. But they still require two sprays for its control. Bt cotton needs one additional spray beside seed treatment for control of sucking pests.
The reported stated that even though disease incidence was noticed at varying intensities at different centres, there was no distinct difference in the susceptibility to diseases between Bt and non-Bt hybrids. All were susceptible, at varying degrees, to diseases. In fact Bt Mech 184 and Bt Mech 12 showed higher susceptibility to bacterial blight, grey mildew diseases.
Bt cotton hybrids showed a marginal improvement in ginning out turn over their respective non-Bt counterparts. There was also no difference in lint index between the Bt and the non-Bt counterparts.

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