FIGURE 7
The activities of the four enzymes in relation to starch synthesis in
grain exhibited variable responses
to stresses (Figure 8). Compared with CK, sucrose invertase activity was
decreased by 30% in DS, 41% in HS and 30% in DHS on the
10th DAP for
superior grain. For inferior
grain, it was reduced by 57% in DS, 40% in HS and 51% in DHS. Similar
or even higher sucrose invertase activity was observed on the
25th DAP in stress treatments (Figure 8a). For sucrose
synthase activity, it was decreased by 30-45% on the
10th DAP and by 28-39% on the 25thDAP for superior grain in stress treatments. For inferior grain, it was
decreased by 19-21% on the 10th DAP in stress
treatments (Figure 8b). For ADP Glc pyrophosphorylase activity, it was
decreased by 21-67% on the 10th DAP and by 16-50 %
on the 25th DAP for superior grain in the stress
treatments compared with CK. For inferior grain, lower ADP Glc
pyrophosphorylase activity was observed in both DS and DHS treatments
(Figure 8c). For starch synthase activity, it was decreased by 22-34%
on the 10th DAP in stress treatment for superior grain
(Figure 8d).