Effect of salinity on relative water content and pigment concentration in three genotypes of bean (Phaseolus vulgaris L.)

Abstract

This work was developed at the Agricultural Research Institute “Jorge Dimitrov” in November 2011, with the aim of studying the effect of salinity on the relative water content (RWC) and the concentration of pigments in plants of three varieties of beans (Phaseolus vulgaris L.): HOL-17 HOL-35 HOL-74, using a saline soil (EC 5.2 dS.m-1) and a non-saline soil as control. The Relative Water Content (RWC) was determined by the method described by Yamasaki and Rebello and the concentration of pigment by the methodology of Lichtenthaler and Wellburn. The results indicated a significant decrease in the RWC in the saline treatment, relative to control, in the three studied varieties. The content of chlorophyll b was affected in the three varieties under saline conditions, while HOL-17 and HOL-74 varieties exhibited a significant increase in the concentration of carotenoids, suggesting a protective mechanism of chlorophyll photooxidation induced by salt stress.

Keywords

• bean
• saline stress
• pigment