Genetically modified, insect-resistant Bacillus thuringiensis (Bt) cotton is cultivated extensively in Pakistan. Past studies, however, have raised concerns about the prevalence of Bt cotton varieties possessing weak or nonperforming insect-resistance traits conferred by the cry gene. We examine this issue using data drawn from a representative sample of cotton-growing households that were surveyed in six agroclimatic zones spanning 28 districts in Pakistan in 2013, as well as measurements of Cry protein levels in cotton tissue samples collected from the sampled households’ main fields. The resultant dataset combines information from 593 sampled households with corresponding plant tissue diagnostics from 70 days after sowing, as well as information from 589 sampled households with corresponding diagnostics from 120 days after sowing. Our analysis indicates that 11 percent of farmers believed they were cultivating Bt cotton when, in fact, the Cry toxin was not present in the tested tissue at 70 days after sowing (i.e., a Type I error). The analysis further indicates that 5 percent of farmers believed they were cultivating non-Bt cotton when, in fact, the Cry toxin was present in the tested tissue (i.e., a Type II error). In addition, 17 percent of all sampled farmers were uncertain whether or not they were cultivating Bt cotton. Overall, 33 percent of farmers either did not know or were mistaken in their beliefs about the presence of the cry gene in the cotton they cultivated. Results also indicate that toxic protein levels in the plant tissue samples occurred below threshold levels for lethality in a significant percentage of cases, although these measurements may also be affected by factors related to tissue sample collection, handling, storage, and testing procedures. Nonetheless, results strongly suggest wide variability both in farmers’ beliefs and in gene expression. Such variability has implications for policy and regulation in Pakistan’s transgenic cotton seed market.

Through biochemical technique of SDS-PAGE, 136 genotypes of rapeseed (Brassica napus L.) were characterized based on total seed storage proteins. The germplasm used in the study consisted of 135 accessions and one check cultivar obtained from Gene-bank of Plant Genetic Resources Institute (PGRI), NARC, and Islamabad, Pakistan. During this study 12.25% polyacrylamide gels were used and a total of 21 protein sub-units were observed among the genotypes. Out of these 21 bands, 16 (76.19%) were polymorphic and the rest of 5 (23.81%) were monomorphic. The 21 protein sub-units were found within the range of molecular weights from 6 to 180 kDa. The similarity coefficient among these genotypes ranged from 0.83 to 0.98. The genotypes studied were divided into five major clusters through constructing the dendrogram on the basis of dissimilarity matrix using UPGMA (unweighted pair group method with arithmetic averages). Overall a low level of genetic divergence was found. So, it is suggested that to find out high level of genetic diversity among these genotypes 2-D gel electrophoresis along with other modern techniques should be practiced in future because SDS-PAGE technique alone is insufficient to fully explore the genetic diversity present in these genotypes.

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