تستر تحت شرايط تنش خشكي X تجزيه ژنتيكي برخي از صفات مورفوفيزيولوژيك در آفتابگردان با استفاده از طرح تلاقي لاين

Genetic analysis some of the morphophysiological traits using line x tester mating design of sunflower under drought stress condition

In order to genetic analysis of some morphophysiological traits of sunflower under water deficet and normal conditions, this research was conducted in the form of linextester design at Seed and Plant Research lmprovment Institue of Karaj, Iran in 2002. Thirty-six entries including 3 lines with cytoplasmic male strilities, 8 restorers and 24 their hybrids and one open-pollinated variety (Armaviruski) were grown in simple lattice design with two replications under two experiment conditions. Experiment was irrigated on the basis of evaporation from 60 mm class A pan where as in stress experiments were irrigated on the basis of evaporation from 180 mm class A pan. The plants stage at which stress was applied was 6-8 leaves stage. In this research, different morphophysiological traits were measured. Analysis of variance of measured traits in two environmental conditions showed significant differences among genotypes in all traits. To study combining ability, linextester analysis was used using procedures developed by Kempthorne, Singh and Choudari. On the basis of line significant variances for traits such as oil seed content, plant height, stem dry matter and head dry matter in two experiments, addative variance was estimated singificant. Also tester variances for oil seed content, stem dry matter and head dry matter were not significant in two environmental conditions and variances of linextester were significant for stem dry matter and head dry matter in drought conditions. Lines contribution in the most cases for traits such as oil seed content, stem dry matter weight and head dry matter weight was more in two experiments.