Identification of Cold-Tolerant Olive Genotypes Based on Physiological and Biochemical Traits Using Genotype-By-Trait Biplot Analysis

• Published in: Journal of plant growth regulation 2024-03, Vol.43 (3), p.716-726
• Main Authors: Dadras, AhmadReza, Azimi, Mahmoud, Taheri, Mehdi, Abdollahi, Azizollah
• Format: Article
• Language: English
• Subjects: Agriculture; Biomedical and Life Sciences; Cell death; Cold; Cultivars; Edible oils; Environmental stress; Fruit trees; Genotype & phenotype; Genotypes; Graphical methods; Life Sciences; Olives; Physiology; Plant Anatomy/Development; Plant Physiology; Plant Sciences; Proline; Stomata
• ISSN: 0721-7595; 1435-8107
• DOI: 10.1007/s00344-023-11130-9

The olive tree is one of the oldest fruit tree cultivars in the ancient world and is the primary source of edible oils and olives. Like many other plants, the olive tree is susceptible to cold stress, one of the most significant environmental stresses that can lead to reduced plant yield or cell death. In this study, the researchers implemented a graphical analysis of the genotype-by-trait (GT) biplot for the first time to identify cold-tolerant olive genotypes. The study was conducted at the Tarom Olive Research Station on 16 olive genotypes with 15 physiological and biochemical traits. According to the GT biplot, the first and second components explained 40% and 20%, and 60% of the total variance, respectively. Concerning the correlation between traits and proline as a criterion, the biplot ranking of different genotypes based on proline content revealed that Zard, Grossane, Abou-satl, Picual, Konservolia, Cornicabra, and Amin cultivars exhibited above-average proline content. Furthermore, Grossane, Cornicabra, Abou-satl, Picual, Zard, and Kaissy cultivars were simultaneously identified as superior based on a pair of proline and stomatal conduction traits. In contrast, the Koroneiki, Meshkat, and Direh cultivars ranked lowest when these two traits were evaluated simultaneously. The hypothetical ideal genotype indicated the genotype with the highest values based on all variables according to the biplot graphic method. Other genotypes were ranked based on their distance from this genotype; the cultivar closest to the hypothetical ideal genotype was Grossane, a cold-tolerant genotype. Next in line were the Abou-satl, Zard, Picual, Konservolia, Cornicabra, and Amin cultivars. This study demonstrates that the graphical method of GT biplot can be used effectively to identify superior genotypes for simultaneously improving several traits.