Morphometric and molecular properties of Aloe vera (L.) under water deficit and salinity conditions

Abstract

Aloe vera (L.) is a well-known plant with valuable properties attributed to the polysaccharides present in its gel, particularly acemannan. However, the structure and composition of these polysaccharides can be influenced by environmental factors prevailing in arid regions. This study aimed to compare the morphometric and molecular behavior of A. vera under semi-controlled conditions of shade netting in response to water deficit and salinity. A randomized block design with four replications was used, featuring large plots with two soil moisture contents (20.7% field capacity and 12.3% permanent wilting point) and small plots with five salinity levels (0, 20, 40, 60, and 80 mM NaCl). Results showed a reduction in leaf width and thickness, fresh biomass, and gel percentage, but an improvement in gel quality. Additionally, an RNA extraction method suitable for samples with high polysaccharide content is described. Finally, RT-qPCR (Reverse Transcription Quantitative Polymerase Chain Reaction) analysis revealed a positive regulation of a glucomannan mannosyltransferase (GMMT) gen of A. vera induced by salinity and salt-water stress combination.