Invertase specific activity measured a in bottom (B) middle (M) and top (T) portions b in source leaf (L1), LTM leaf (L2) and sink leaf (L3). c SPS specific activity measured in bottom (B) middle (M) and top (T) portions d in source leaf (L1), LTM leaf (L2) and sink leaf (L3) of CoJ64 at 210, 240, 270, 300 and 330 DAP. Errors bars indicate ± SD from three independent experiments