Figure 2.

MaDREB1F overexpression increases banana resistance to cold and drought stress. (a) T-DNA region of pCAMBIA1302 for generating transgenic plants. (b) Floral apex slices on differentiation medium. (c) Callus regenerated from floral apex slices. (d) Induction of shoot growth on shooting medium. (e) Shoot growth to 3 cm in height. (f) Rooting of explants on rooting medium. (g) Hardening of rooted transgenic plants. (h) Integration of MaDREB1F transgene in lines L1 and L2 from Southern blot analysis. M, marker; PC, positive control. (i) Amplification of hpt-II gene by PCR in transgenic lines. (j) MaDREB1F expression in transgenic lines using qRT–PCR. Duncan’s range test was used for significance examination (n = 3; P < .05). (k) 100-day-old banana seedlings were exposed to cold conditions (8°C) for 5 days and recovery for 10 days, then photographs were taken. (i) 100-day-old banana seedlings were treated by withholding water for 10 and 15 days and recovery for 10 days, then photographs were taken.