Effect of different levels of water deficit on yield and amount of osmotic regulator in tetraploid and hexaploid wheat genotypes
To investigate the effect of water deficit stress on yield and osmotic regulator of tetraploid and hexaploid wheat genotypes an experiment was carried out at Research Station of Islamic azad university of Miandoab in 2015. The soil texture of experimental site was sandy loam. The research field was located in a semi-arid region. This experiment was conducted as factorial based on completely randomized block design with three replications. Water deficit levels were A: control (normal condition), B: no irrigation of fertilization stage, C: no irrigation of grain filling stage. Studied genotypes were hexaploid of bread wheat ‘Sabalan’ and ‘Zarrin’ and tetraploid of durum wheat ‘Syrian-4’ and ‘Zardak’. Plant density was 400 plants.m-2. In the present experiment data showed that under severe water deficit (non-irrigated stage of pollination) situations, the highest and the lowest grain yield belonged to tetraploid genotype of durum wheat ‘Zardak’ and hexaploid genotype of bread wheat ‘Zarrin’. Under severe water deficit conditions, the highest decrease in grain yield as well as concomitant increase in proline content were seen in bread wheat of ‘Sabalan’ and ‘Zarrin’. However, the highest amount of grain yield and proline content were observed in durum wheat of ‘Syrian-4’ and ‘Zardak’. In total, water deficit had adverse effects on yield of wheat genotypes had negligible potential to compensate the deteriorative effects of water deficit condition and these condition tetraploid durum wheat for the cultivation and production of superior hexaploid wheat bread.