Affiliations: Department of Agronomy and Plant Breeding, Faculty of Science and Agricultural Engineering, Razi University, Kermanshah, Iran
Corresponding author: Leila Zarei, Department of Agronomy and Plant Breeding, Faculty of Science and Agricultural Engineering, Razi University, Kermanshah, Iran. Tel.: +98 9122519289; Fax: +98 8338233731; E-mail: Lzarei1360@yahoo.com.
Abstract: BACKGROUND:The strawberry is one of the most important small fruits; it is widely cultivated in the world and is sometimes subjected to drought stress. Investigating the effects of drought stress on cultivar related plant physiology is necessary to broaden the knowledge of resistance mechanisms to drought. OBJECTIVE:The present study was conducted to investigate the morpho-physiological characteristics of drought tolerance and the relationships between these and strawberry fruit yield under short- and long-term drought stress conditions. METHODS:The effect of two strawberry cultivars, Queen Eliza and Parus, was examined under four moisture regimes. A short-term stress for one month and a long-term stress for four months were undertaken in greenhouse condition. RESULTS:The analysis of variance indicated significant differences between the cultivars for carotenoid content, relative water content, relative water loss, stomatal conductance and quantum yield of photosystem II under short-term stress and stomatal conductance, and carotenoid content and membrane stability under long-term stress. Correlation analysis revealed that yield correlated positively with relative water content and quantum yield of photosystem II (Fv/Fm), under short- term and long- term stress. Using factor analysis, totally four factors were identified that accounted for 82.14% of the total variance. The factors were in decreasing order of influence yield components, photosynthesis, physiological characteristics and chlorophyll. CONCLUSIONS:Generally, ‘Parus’ was superior to ‘Queen Eliza’ in terms of measured traits under short and long-term stress conditions. It seems that measuring physiological traits is a convenient, simple and fast tool for screening genotypes for their drought tolerance.