WANG Dong-Mei, LI Hai-Qiang, DING Rui-Feng, WANG Fei, LI Hao-Bin, XU Yao, AHTAM Uwayis, LIU Jian
Cotton Science. 2012, 24(1): 18-26.
To study the spatial and temporal expression of Bt insecticidal protein in transgenic Bt cotton planted in northern Xinjiang Province, Bt insecticidal protein levels in four transgenic Bt cotton varieties (CCRI 43, GK62, GK19, sGK321), were quantitatively tested and compared during different developmental periods in 2009 and 2010, using the ELISA method. Trends in the spatio-temporal expression of Bt insecticidal protein were basically consistent between 2009 and 2010, although the expression amount was different, and some varieties had significant differentiation. Bt insecticidal protein levels varied with organs and developmental periods. The Bt insecticidal protein content gradually decreased with cotton development. The Bt insecticidal protein content of the cotyledon was the highest, and levels in the tender leaves during the cotyledon period, the three-leaf period, and the seven-leaf period were higher than those in the tender leaves, squares, petals and young bolls during the squaring period, flowering period, bolling period, respectivesly. Bt insecticidal protein levels in squares during the squaring period were higher than those in the flowering period and bolling period, and the levels in petals during the flowering period were higher than those during the bolling period. In the squaring period, the tender leaves had more Bt insecticidal protein than the squares; but in the flowering period, the squares had more Bt insecticidal protein than the tender leaves or the petals. In the bolling period, Bt insecticidal protein levels in tender leaves and squares were higher than those in petals and young bolls. The expression level of Bt insecticidal protein in transgenic Bt cotton can thus be influenced by the kind of organ, the developmental period, variety, and planting season.