Determination of Fatty Acids, Tocopherols, Selenium and Total Carotene of Walnut Genotypes and Evaluations by Cluster, Pca and Correlation Analysis

Abstract

Plant genetic diversity creates unique and unrivaled resources for future climate change scenarios. Knowledge of these genetic resources and their sustainable management are essential for the development of conservation strategies. Selection studies are also the basis of these investigation. In this study, 27 selected walnut genotypes grown in the Batman region of Southeastern Anatolia were assessed for fatty acid composition, total carotene content, selenium, as well as their tocopherol content. The total fat varied between 53.25 and 68.70%. The fatty acid content was found to be 38.86-64.37% for linoleic acid, 16.27-38.20% for oleic acid, 9.58-19.38% for linolenic acid, 4.09-6.55% for palmitic acid and 1.78-4.05% stearic acid. The amount of alpha-tocopherol, gamma-tocopherol and delta-tocopherol were found to be 2.25-6.32 mg kg(-1), 38.20-136.27 mg kg(-1) and 1.65-6.21 mg kg(-1), respectively, and total tocopherol content was 89.85 mg kg(-1). Selenium contents of genotypes were between 12.28 and 65.32 mg g(-1). The genotypes were found to have 0.19-0.56 mg kg(-1) total carotene. Cluster and PCA analyses were performed and two major clusters were identified. Compared to cluster A, 72-K-11, 72-K-129, 72-S-48 and 72-K-92 genotypes in cluster B generally had the highest kernel ratio (52.609%), oleic acid (30.26%), linoleic acid (55.02%), linolenic acid (18.14%), gamma-tocopherol (122.31 mg kg(-1)), delta-tocopherol (4.45 mg kg(-1)) and selenium (50.25 mg g(-1)). The present results emphasize that the walnut genotypes selected from the Southeastern Anatolia Region can make an important contribution to human nutrition with their rich fatty acids, tocopherols and selenium contents.