Fig. 2

Effects of Bacillus thuringiensis (Bt) genes on potassium (K) concentration (A–D), accumulation (E–G) and utilization index (I, the dry matter produced per unit K concentration at the plant level) in roots (A, E), stems (B, F), leaves (C, G) and reproductive parts (D, H, including squares, flowers, and bolls) of cotton plants in the field. The available K+ in soil was 47.8 mg·kg−1. DAS: days after sowing. WT: wild type (Jihe 321); OE-29317 and OE-29312: transgenic Bt lines. Bars with different letters indicate significant differences within the same day (P < 0.05). Error bars depict standard errors of the mean