نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکتری، دانشکده کشاورزی، واحد سنندج، دانشگاه آزاد اسلامی، سنندج، ایران
2 استادیار، دانشکده کشاورزی، واحد سنندج، دانشگاه آزاد اسلامی، سنندج، ایران
3 استادیار، گروه اصلاح نباتات، دانشکده کشاورزی، دانشگاه شاهد، تهران، ایران
4 استاد پژوهش، مؤسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، ترویج و آموزش کشاورزی،کرج، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction
Durum wheat is considered one of the most important crop plants globally and in Iran, and it’s growth and yield is consistently affected by drought stress in Mediterranean regions, especially with global climate changes. However, local varieties or landraces of this crop can serve as valuable genetic resources for identifying and introducing drought-tolerant genotypes. The objective of the present study was to evaluate the drought tolerance of Iranian and foreign durum wheat landraces (primarily from the Fertile Crescent) in order to identify and introduce superior genotypes.
Materials and Methods
In this study, 150 durum wheat landraces from the Fertile Crescent were assessed for drought tolerance using stress tolerance indices. The experiment was conducted in an augmented randomized complete block design with four check varieties under supplementary irrigation and rainfed conditions in the research field of Razi University, Kermanshah, Iran, during two consecutive years (2019-2020 and 2020-2021). Stress tolerance indices were calculated after measuring grain yield under both supplementary irrigation and rainfed conditions. Cluster analysis, principal component analysis, and biplot analysis were used to screen the studied landraces for drought tolerance. R software version 4.3.1 was used to calculate stress tolerance indices and homogeneity test of variance of experimental errors. R software was used to perform principal component analysis and determine the optimal number of groups based on Silhouette method in Factoextra package.
Research findings
The results of combined analysis of variance of the two years data revealed a significant difference among the studied durum wheat landraces for grain yield under both supplementary irrigation and rainfed conditions. The interaction of genotype × year was also significant, indicating different responses of the genotypes during two experimental years. Biplot analysis of genotype × index for the first year data showed that all the studied stress tolerance indices appeared in the first, third, and fourth zones of the coordinate axes, but more important stress indices including MP, TOL, GMP, HM and STI were located in the fourth zone, which were used to identify superior with high yielding drought-tolerant genotypes. A similar trend with minor differences was observed in the second year. In total, the studied durum wheat landraces were categorized into four distinct groups from drought-sensitive to drought-tolerant based on the genotype × index biplot.
Conclusion
Based on the results of this study, TOL, GMP, HM, STI and MP indices were selected as suitable and useful indices for distinguishing and identifying high-yielding drought-tolerant durum wheat landraces. Accordingly, the studied durum wheat landraces in terms of drought tolerance or sensitivity were grouped into four distinct groups from sensitive to tolerant. Among the studied landraces, two landraces, 44SAU and 9IRQ from Sudan and Iraq, respectively, were identified as superior landraces.
کلیدواژه‌ها [English]
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