Strategies to select genetic variations of barley (Hordeum vulgare L.) cultivars for agronomic zinc utilization characters

Author: M. Rüştü Karaman ¹, Nejdet Kandemir ², Sezer Şahin ^1* and Serpil Çoban ¹

Received 10 February 2010, accepted 8 April 2010.

Abstract

Zinc deficiency limits cereal production in soils especially with high lime content. In order to eliminate this problem, it is necessary to use cultivars that use the available zinc better. In this study, zinc sulphate heptahydrate (ZnSO₄.7H₂O) was used as Zn fertilizer at the levels of 0 (-Zn) and 10 mg Zn kg^-1 (+Zn) in a zinc-deficient calcareous soil. Twenty barley genotypes from Europe, North America and Turkey were used to determine genotypic differences under zinc deficient soils and after zinc application in a greenhouse pot experiment. There were significant differences among the genotypes used for plant dry weight, zinc concentration and uptake. There was a significant correlation (r = 0.67**) between dry matter yield and Zn uptake in Zn-treated conditions. The results showed that changes in the Zn utilization characters of barleys were related to the plant genotypes and Zn levels. Dry weight (DM) and total Zn content of the plants were used to calculate the efficiency index parameter for classification of genotypes which was evaluated to select barley genotypes with improved Zn utilization characters as ER (efficient responsive), ENR (efficient non- responsive), IR (inefficient responsive) and INR (inefficient non-responsive). The linear regression analysis between dry matter weight and EI for Zn-10 level had a significant degree of association, and the regression equation was DM = 0.0226*EI + 2.9791. As a result of the classification, the barley genotypes Yesevi-93, Baronesse, Steptoe, Harrington, Bülbül as ER, Avusturalya, Özdemir-2005, Orza, Ince-2004 as ENR, Morex, Tarim-92, Rihane, Dicktoo, NE-93760, Kaya, Kearney as INR, and Schuyler, Golden Promise, Barke, Yerçil-147 as IR were defined. Thus, barley cultivars defined as ER and ENR could be used for the development of barley cultivars with better Zn responses. Considering the fact that about half of the cereal areas are low in available Zn content, development and use of cultivars that use Zn more efficiently will be valuable for further breeding studies. The results have revealed that these practical classification strategies could be confidently evaluated for further agricultural breeding studies which will lead to economical and environmental benefits.

Key words: Barley genotypes, zinc fertilizer, zinc utilization.