Document Type : Original Article

Authors

• Roghayeh Fatemi ¹
• Mehrdad Yarnia ²
• Soleiman Mohammadi ³
• Ebrahim Khalil Vand ⁴
• Bahram Mirashkari ²

¹ Ph.D. Student, Department of Agronomy and Plant Breeding, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

² Associate Professor, Department of Agronomy and Plant Breeding, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

³ Seed and Plant Improvement Research Department, West Azerbaijan Agricultural and Natural Resources Research Center, AREEO, Urmia, Iran.

⁴ Assistant Professor, Department of Agronomy and Plant Breeding, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

Abstract

Introduction
Barley (Hordeum vulgare L.) is a widely cultivated cereal crop in many rainfed areas in the Mediterranean region where drought is considered the main yield-limiting factor. In such marginal lands, yield losses is associated with drought conditions resulted from low and inconsistent precipitation during the whole plant growth cycle, either early in the fall or winter (initial drough conditions) or late during spring (terminal drought).Drought stress reduces grain yield of barley through negative affecting the yield components i.e. number of plants per unit area, number of spikes and grains per plant or unit area and single grain weight, which are determined at different stages of plant development.
Materials and methods
In order to Consistency Study, Grain Yield Potential and Relationship between Traits in Spring Barley Cultivars and Lines, an experiment was done in Agricultural and Natural Resources Research Station of Miandoab in cropping 2016-2017. In this research, 12 lines and variety were evaluated in a randomized complete block design with three replications under complete irrigation and cut irrigation after 50% flowering (Grain filling water stress). In present study Plant Height, spike length, Peduncle length, Spike weight, spike number / m2, Grain number / spike, 1000 grain weight, Biomass, Grain yield and harvest index were measured. Analysis of variance was performed using the SAS9.4 and SPSS programs.
Result
Results of analysis of variance showed that there was a significant difference between genotypes for all traits, Also, Also, the interaction of genotype in conditions was significant on all traits except spike length and 1000-grain weight. results showed that water deficit redused plant height, peduncle length, grain number per spike, 1000 seed weight, biomass, grain yield and harvest index by 8.39, 2.10, 7.03, 46.63, 37.18, 42.79 and 5.71 percent respectively. Among the studied genotypes, jonoob cultivar, M-88-2 and MD-88-15 by 4.42, 4.43 and 4.93 t/ha under normal condition and 3.44, 3.75 and 3.66 t/ha respectively under water deficit condition produced the highest grain yield compared to other genotypes. In both conditions correlation of grain yield with spike weight, number of grain per spike, biological yield and harvest index was positive and significant. Based on stepwise regression analysis, under normal conditions, number of seeds per spike, spike weight and number of spikes per square meter (with, R2 = 0.76), and under water deficit condition grain number, plant height and 1000 grain weight (with, R2 = 0.62), justified in grain yield variation. Based on the results of path analysis in normal conditions, seeds per spike, spike weight and number of spikes per square meter and in water deficit condition grain number, plant height and 1000 grain weight had a direct positive and significant effect on grain yield. In percent study seed number per spike was identified as the most effective trait for grain yield in both conditions. Cluster analysis classified the cultivars and barley lines under normal condition in two groups and in under water deficit, into three groups, which under normal condition cluster 2 (in cluding lines of Jonoob, M-88-2 and MD-88-15) and in water deficit condition cluster 1 (Jonoob, M-86-5, M-88-2, RIHANE 03 and MD-88-15) were obtained The highest grain yield and yield components.

Conclusion
According to the results of this study, there were a high genetic variation between barley Cultivars lines both normal and water deficit condition. Also genotypes of Jonoob, M-88-2 and MD-88-15 by achieved the highest grain yield in both conditions were identified as the most suitable genotypes for cultivation in the West Azarbaijan region. Also, grain number per spike in both conditions was recognized as the most effective trait on grain yield.

Keywords

• Correlation
• Grain yield
• Spring Barley
• Stepwise Regression Cluster Analysis
• Water deficit