Impact of Bt-cotton on soil microbiological and biochemical attributes. (1st October 2016)

• Record Type: Journal Article
• Authors: Yasin, Sanaullah; Asghar, Hafiz Naeem; Ahmad, Fiaz; Ahmad Zahir, Zahir; Waraich, Ejaz Ahmad
• Is Part Of: Plant production science. Volume 19:Number 4(2016)
• Page Start: 458
• Page End: 467
• Publication Date: 2016-10-01
• Subjects: Bt-cotton -- Bt-toxin -- ecology -- phosphatase -- dehydrogenase -- rhizosphere; Agronomy & Crop Ecology; Plant products -- Periodicals; Field crops -- Periodicals; 571.2
• DOI: 10.1080/1343943X.2016.1185637
• Languages: English
• ISSNs: 1343-943X

Abstract

Abstract: Transgenic Bt -cotton produces Bt -toxins ( Cry proteins) which may accumulate and persist in soil due to their binding ability on soil components. In the present study, the potential impacts of Bt - and non- Bt genotypes of cotton on soil microbial activity, substrate use efficiency, viable microbial population counts, and nutrient dynamics were studied. Two transgenic Bt -cotton genotypes (CIM-602 CIM-599) expressing cry1 Ac gene and two non- Bt cotton genotypes (CIM-573 and CIM-591) were used to evaluate their impact on biological and chemical properties of soil across the four locations in Punjab. Field trials were conducted at four locations (Central Cotton Research Institute-Multan, Naseer Pur, Kot Lal Shah, and Cotton Research Station-Bahawalpur) of different agro-ecological zones of Punjab. Rhizosphere soil samples were collected by following standard procedure from these selected locations. Results reveled that Bt -cotton had no adverse effect on microbial population (viable counts) and enzymatic activity of rhizosphere soil. Bacterial population was more in Bt -cotton rhizosphere than that of non- Bt cotton rhizosphere at all locations. Phosphatase, dehydrogenase, and oxidative metabolism of rhizosphere soil were more in Bt -cotton genotypes compared with non- Bt cotton genotypes. Cation exchange capacity, total nitrogen, extractable phosphorous, extractable potassium, active carbon, Fe and Zn contents were higher in rhizosphere of Bt -cotton genotypes compared with non- Bt cotton genotypes. It can be concluded from present study that the cultivation of Bt -cotton expressing cry1 Ac had apparently no negative effect on metabolic, microbiological activities, and nutrient dynamics of soils. Further work is needed to investigate the potential impacts of Bt -cotton on ecology of soil-dwelling insects and invertebrates before its recommendation for extensive cultivation.