Assessment of drought tolerance indices in tall fescue genotypes  (Festuca arundinasea Schreb.)

Ebrahimiyan, Maryam; Majidi, Mohammad-mahdi; Mirluhi, Aghafakhr; Gheysari, Mahdi

doi:10.22092/ijrfpbgr.2011.7644

Assessment of drought tolerance indices in tall fescue genotypes (Festuca arundinasea Schreb.)

Document Type : Research Paper

Authors

10.22092/ijrfpbgr.2011.7644

Abstract

In order to study drought tolerance indices and to identify drought tolerant genotypes, 75 genotype of tall fescue (Festuca arundinace) (25 early maturity, 25 late maturity and 25 parental genotypes) were evaluated under moisture stress and non-stress field environments using a randomized complete block design for each environment in the research farm of Isfahan University of Technology, Isfahan, Iran. Five drought tolerance indices including mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), stress susceptibility index (SSI), and tolerance index (TOL) were calculated. Analysis of variance for each maturity group showed that there was a significant genetic variation among genotypes for all criteria. Correlation analysis showed that MP, GMP and STI had significant and positive correlation coefficient with yield under both stress and non stress conditions, suggesting that these indices are more efficient in determining drought tolerant genotypes. Based on multivariate biplot on all indices and triple plot on the two most important indices (STI and GMP) similar genotypes were indentified as the most tolerant genotypes in low irrigation condition. These were genotypes number 21 and 23 in parental group, numbers 10 and 23 in early maturing group and 3, 5 and 13 in late maturing group. Classification of genotypes using cluster analysis based on the three indices of MP, GMP and STI confirmed the results of biplot and triple plot for identifying tolerant genotypes.

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