3.2. Proline accumulation in response to salinity
Proline (Pro) is an osmoprotectant that has been shown to
accumulate in plants in response to salinity stress [27]. Earlier
studies from this laboratory showed that there is high
accumulation of Pro in salt sensitive rice IR20 [28]. In concurrence
with this, our results (Fig. 1E) show that the salt
sensitive cv. PB accumulates significantly higher levels of
Pro under stress. For instance, when exposed to 200mM
NaCl, cv. PB accumulated over 20-fold more Pro than control.
In contrast, only a negligible increase in Pro level was
observed in the tolerant cv. PK under NaCl stress.
3.3. Lipid peroxidation as an indicator of
oxidative damage
Changes in lipid peroxidation serves as an indicator of the
extent of oxidative damage under stress [29]. To determine