New Delhi -- Monday, May 02, 2005
Bt cotton prone to diseases: study
ASHOK B SHARMA
NEW DELHI, MAY 1: A study conducted by a team of cotton experts from the government has noted that Bt cotton hybrids are susceptible to diseases like bacterial blight, alternaria leaf spot and grey mildew.Bacterial blight,alternaria leaf spot and grey mildew were the major diseases on cotton identified in central and southern parts of the country in 2004 season.
This report of the government body confirms the claims by different studies conducted by civil society organisations and independent scientific bodies pointing to the failure of Bt cotton in 2004 season. It also justifies the claims of Andhra Pradesh Bt cotton growers for compensation for crop loss.
The Genetic Engineering Approval Committee (GEAC) has withheld its decision to extend the approval period for three varieties of Mahyco-Monsanto'Bt cotton, on getting adverse reports about its performance.
Farmers leader Mallareddy of AP Rythu Sangam has written to GEAC not to approve extension period for "three failed Bt cotton hybrids," while S Jaipal Reddy of the Federation of Farmers Association (FFA) has demanded immediate extension of the approval period. FFA and its leaders have entered into close partnership with the apex industry body, Confederation of Indian Industries (CII) and have floated Farmers-Industry Alliance.
All India Coordinated Cotton Improvement Project (AICCIP) in its annual report for the year 2004-05 said: "The Bt cotton hybrid trials laid out in the central and south zone centres were assessed for the occurrences of Alternaria leaf spot, grey mildew and bacterial blight. A comparative study on the incidence of diseases on Bt and non-Bt cotton was carried out.
The results revealed that both Bt and non-Bt cotton hybrids are equally susceptible to bacterial blight, alternaria leaf spot and grey mildew. The results indicate that the presence of Bt gene does not have any impact on the nost susceptibility and disease development in the Bt cotton hybrids tested so far."
The AICCIP report added: "The outbreak of alternaria leaf blight and grey mildew disease in central and south zones was significant, especially in hybrids such as Bunny and certain Bt hybrids. The critical damage of these diseases at peak boll formation stage was quite threatening, while adequate pre-emptive control measures were taken by AICCIP by alerting the local state agricultural departments."
Three separate teams for evaluation of Bt cotton for north, central and south zones were constituted by AICCIP. The teams studied breeding, entomology and pathology.
Regarding the south zone, the AICCIP report said: "All the hybrids tried at Lam, Siruguppa and Coimbatore were statistically on par, whereas in Nandyal, Mech 12 Bt and Mech 162 Bt gave significantly higher seed cotton yield over NHH-44.
In Dharwad, Mech 184 Bt and RCH 2 Bt seems to be superior over Mech 162 Bt." This means all cotton hybrids - whether Bt or non-Bt - had same yields as per the evaluations made in Lam, Siruguppa and Coimbatore. Only the evaluation done in Nandyal showed Bt hybrids having more yields than non-Bt varieties. The AICCIP study said the farmers practicing integrated pest management (IPM) benefited in net income and the number of pesticide sprays were reduced by nearly 50%.