1- University of Zanjan
Abstract: (7 Views)
Introduction and Objective: The impact of climate change on agricultural production has emerged as one of the important research priorities in recent decades. In this regard, drought stress plays a critical role in reducing crop yield and adversely affects agricultural production worldwide. In Iran, lentil is mainly cultivated in the spring under rainfed conditions. This cropping system is associated with challenges, including low grain yield and production fluctuations. Shifting to a fall-sown cropping system could be an effective strategy to increase yield potential and production stability. However, the success of this strategy depends on the identification, evaluation, and introduction of cold-tolerant cultivars.
Materials and methods: The present study was conducted during the 2023–2024 growing season at the research farm of the Faculty of Agriculture, University of Zanjan. Twenty-nine native lines, 11 lines from the International Center for Agricultural Research in the Dry Areas (ICARDA), four cultivars from the Field Crops Central Research Institute (FCCRI), Turkey, one unknown genotype and four control checks were evaluated under regional rainfed conditions. The experiment was laid out in a randomized complete block design with three replications. Days to 50% flowering, days to 50% podding, days to 50% maturity, and grain filling period were recorded. Three plants were randomly selected from each plot to measure morphological traits, including plant height, lowest pod height, and height of most pods. Grain yield per plant, number of seeds per plant, straw weight per plant, biomass per plant, thousand-grain weight, and harvest index were recorded. Survival percentage was used to assess cold tolerance. The analysis of variance and hierarchical clustering were conducted using R software. The deviation of the mean of each cluster from the overall mean was calculated using standardized data. Mean comparisons were performed using Duncan’s multiple range test. Phenotypic and genotypic coefficients of variation and heritability were estimated.
Results: The minimum air temperature recorded during the growing season was −12.5 °C. A late-spring frost at −2 °C occurred during the flowering of the genotypes. Analysis of variance revealed highly significant differences (P < 0.001) among genotypes for all measured traits. High phenotypic and genotypic coefficients of variation were observed for the number of seeds per plant, grain yield per plant, biomass per plant, and straw weight per plant. The cluster heatmap grouped the genotypes into four distinct clusters. Genotypes 33, 17, 12, 3, 42, and 23 had the lowest survival percentages and were assigned to the I and II clusters; all were derived from ICARDA. Clusters III and IV had a higher survival percentage than the overall mean. Native lines 7, 8, 26, 44, 38, 40, 34, 29, and 4, all with survival percentages exceeding 90%, were grouped into these clusters. Genotypes with the lowest days to 50% flowering (mainly from ICARDA) were grouped in Cluster II. Clusters III and IV, mainly composed of native lines, exhibited grain yield and seed number means higher than the overall mean. Genotypes 31, 49, 32, and 13 exhibited the highest grain yield and belonged to native lines. Genotypes 38, 13, 1, 31, 44, 32, and 49 exhibited the highest number of seeds, all of which were native lines. In terms of plant height, genotypes 49 and 44 (native line), 16 and 30 (from FCCRI) exhibited the highest values. Genotypes 5 (native line) and 16 showed higher values for the height of the lowest pod, while genotypes 16, 9, and 30 (from FCCRI) demonstrated higher values for the height of most pods.
Conclusions: The valuable genetic variability observed among genotypes can be effectively utilized in breeding programs. High heritability (84%) was observed for survival percentage as a cold resistance indicator. This underscores the potential for effective selection to improve plant survival in lentil under cold stress conditions. The highest-yielding genotypes were found among the native lines. Several FCCRI cultivars exhibited superior performance in height-related traits. A subset of ICARDA lines exhibited desirable phenological traits, such as early flowering and maturity. Integrating diverse genetic resources into breeding programs will accelerate the development of lentil cultivars adapted to rainfed conditions, resistant to cold, and suitable for mechanical harvesting. This study indicates that some evaluated genotypes have favorable potential for adaptation to autumn cultivation. Nevertheless, it is essential to repeat the experiment under on-farm conditions over multiple years for a more precise assessment of yield stability and cold tolerance.
Send email to the article author
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
