Another adaptive response of plants refers to increments of total soluble carbohydrates (Fig 2A), and this occurs due to deficiency of water in soil. Plant promotes an osmotic increase in substances adjusting the adverse conditions, being essential for the maintenance of cellular turgor (Salisbury and Ross, 2012). According to Oliveira Neto (2010), the observed increases are associated with a probable decrease in starch content in the leaf, besides the decrease in photosynthetic capacity paralyzing cell growth by reducing the synthesis of sucrose for export, enabling the increase in the concentration of carbohydrates in cells plant. Other sugars can also function as compatible solutes, promoting the maintenance of water potential by osmotic adjustment and protection of the cells plant during dehydration, forming glassy structures.
Kerbauy (2009) describes an increase in the sucrose-phosphate synthase activity and sucrose synthesis in leaf tissues in response to water stress. Similar results were obtained by Costa et al. (2010), researching the Costus arabicus L. They observed that sucrose concentrations were lower in the control treatment compared plants submitted to water stress for 67 days.