Pakistan's climate is arid to semi-arid and in a climate change scenario where rainfall patterns are expected to be erratic with longer droughts, the survival and growth potential of important forest species is likely to decrease significantly. Therefore, the effect of water stress and the salicylic acid application on the morphological, physiological and behavioral adaptation was tested in three selected tree species Populus deltoides, Dalbergia sissoo and Syzygium cumini in this study. Plants were collected from the UAF forest nursery, and 60 seedlings of uniform size (20 for each species) were selected and randomly assigned to the three treatments (20 under control, 20 under water stress and 20 under drought and salicylic acid). Data on growth, biomass production, biomass partitioning, and physiological and biochemical attributes were collected during the experiment. At the end of the experiment, the recorded data are analyzed statistically using two ANOVA factors (species, treatment and interaction effect; species × treatment effect). The results showed that the growth showed a significant effect on the species, as well as the treatment effect, as water stress negatively affected the plant growth. Interestingly, the dry root biomass remained insignificant across the three treatments. Likewise, the percentage allocation of leaf biomass and root biomass allocation remained similar between the three treatments. Therefore, it can be concluded that despite the large differences observed in all species most of the growth occurred in roots under water stress to improve their ability to absorb water.
Farhan et al. (Sat,) studied this question.