Effects of drought stress on morphology and physiological characteristics of three Melastomataceae species

Effects of drought stress on the morphology and physiological characteristics were investigated， selecting 3 species of Melastomataceae as experimental materials. With fuzzy menbership function value method， the capability for drougt resistance of 3 Melastomataceae species were comprehensive evaluated. The results indicated: the relative conductivity and proline content of all 3 species showed an increasing trend with the increase of soil drought stree. The MDA content were up of Melastoma malabathricum‘ Tianjiao’ and Allomorphia eupteroton var. Teretipetiolata，which peaked under heavy drought stress，while Tibouchina granulosa were up first and then down，which peaked in moderate drough stess（18.1μmol/g）. Protein content of the 3 species were insensitive to drought stress. The soluble sugar content increased first and then increased，which was at lowest volume under slight drough and peaked in heavy drought stress. The result of membership function analysis showed that A. eupteroton var. teretipetiolata and M. malabathricum‘ Tianjiao’ had is stronger drought tolerance，and T. granulosa had weak drought tolerance.