Seed yield and some physiological traits of safflower as affected by water deficit stress

Document Type : Research Paper


Department of Agronomy and Plant Breeding, College of Agriculture, Isfahan University of Technology, Isfahan 8415683111, Iran.


Safflower (Carthamustinctorius L.) is an oilseed crop adapted to drought prone
arid and semi-arid environments. This study was conducted to evaluate the effects
of water deficit stress on antioxidant activity, membrane stability index (MSI), leaf
chlorophyll content, leaf area index (LAI) and their relationship with seed yield
using 64 safflower genotypes grown under normal and water deficit stress field
condition. Plants were grown under normal irrigation until branching growth stage
when water deficit stress was applied to the plants. Analysis of variance showed
the significant effects of genotype, water deficit and their interactions on the
physiological traits that examined. Water deficit stress significantly decreased leaf
area index, leaf chlorophyll content and the membrane stability index means over
all 64 genotypes whereas it caused significant increase in antioxidant compounds
(APX and POX). The results also revealed the positive and significant correlations
between antioxidant enzyme activities with seed yield under water deficit
conditions. The stress susceptibility index (SSI) identified water-deficit tolerant
genotypes (Kordestan 3 and C411) that did have outstanding yield performance per
se in stress environments.