Bt cotton seed purity in Burkina Faso: status and lessons learnt

Table 1 Presence of Bt genes in seeds from fields cultivated with conventional variety

	Presence of Cry1Ac	Presence of Cry2Ab	Double genes presence
Number of sample	297	297	297
Share of samples with presence^a of the concerned Cry gene /%	63.5	59.3	52.2
Presence rate^b of Cry1Ac /%
Mean	41.5		43.1
Std. deviation	23.2		22.5
Presence rate^b of Cry2Ab /%
Mean		39.3	40.3
Std. deviation		23.2	23.3

^a Presence was claimed when observed on at least one out of 11 seeds of each sample
^b Rate of presence in samples where the presence was observed according to the retained criterion, calculated from the number of seeds with Bt gene detected out of eleven

ISSN: 2523-3254