Back to Contents

FREE FULL TEXT PDF

THE POTENTIAL OF USING K/Na RATIO AS INDEX OF SALINITY TOLERANCE IN TOMATO

MARIO V. LOPEZ AND M.E. SATTI

Abstract: The effects of adding K, P and Ca to saline nutrient solutions on K/Na ratio and salinity tolerance in tomato (Lycopersicon esculentum Mill) in five tomato cultivars viz., Tropic, Marikit, Montecarlo, Strain B and Pearson was studied. Addition of K, K+P and K+P+Ca to saline nutrient solutions significantly increased K/Na ratios in the leaf, stem and root as well as fruit yield by 25-35 %, whereas addition of Palone significantly reduced K/Na ratio in the stem but not in the leaf and root with a increase in fruit yield by 9%. Two types of physiological mechanism conferring salinity tolerance to tomato cultivars based on their respective K/Na ratios were detected where Marikit exhibited a typical halophytic characteristic while Tropic, Montecarlo, Strain B and Pearson showed typical glycophytic response, reaction.

Department of Agronomy, College of Agriculture, 2989 Makiling Subdivision, Anos, Los Banos, Laguna 4030, Philippines.