| چکیده انگلیسی مقاله |
Extended Abstract
Background: The PachBaghela (Phaseolus vulgaris) is one of the most widely consumed beans in Guilan province. The growth period of this crop is short, about 60-70 days, and it can be cultivated in spring and summer. The annual cultivated area of PachBaghela is 10-20 thousand hectares, of which about 40 percent is related to spring cultivation. The time of harvesting and consumption of PachBaghela is at the maximum growth stage of immature and discolored pods (before pods dry). Currently, due to the lack of improved varieties, farmers use local landraces of PachBaghela, which offers limited yield, and non-uniform crop production, and has created challenges in the cultivation of this crop. Three types of these landraces are different from other landraces, which in order of importance are black-veined, red-veined, and Brown-veined beans, with black-veined landraces being the most cultivated and preferred by consumers. Therefore, the need to introduce lines with optimal yield and high marketability seems essential. Accordingly, to introduce a promising high-yielding line with appropriate stability, nine PachBaghela lines selected from preliminary yield evaluation experiments resulting from breeding programs of this crop at the Seed and Plant Improvement Institute (SPII), along with the local control landrace, were evaluated.
Methods: This experiment was conducted in three regions of Guilan province (Rasht, Lahijan, Shanderman) in spring for two years (2016 and 2018) in a randomized complete block design with three replications using nine lines (G1-G9) along with the local Kuchsfahan landrace (G10). The lines were sown in late April. It should be noted that these lines were selected from native populations of different regions in Guilan province and were superior in preliminary experiments to evaluate the yield of PachBaghela. The results of the fresh pod yield of the lines were subjected to a combined analysis of variance for the three regions. Of course, before that, the data normality test and homogeneity of variance of environments were examined using Bartlett's test using SAS 9.4 software. The AMMI method was performed using GenStat 12.0 software and PBTools version 2013, and 16 stability methods including S (1-6): Nassar and Hahn stability statistics, NP(1-4): Tanazero stability statistics, Wᵢ²: Rick's equivalent, σ²ᵢ: stability variance Shukla, bi: regression coefficient, S²dᵢ: deviation from the regression line, CV: coefficient of variation, θ(i): Genotype-environment interaction variance, θᵢ: average plastid variance, KR: total Kang rank, were calculated using STABILITYSOFT software. The mean and standard deviation of the stability statistics rank for each line were calculated using EXCEL software, and a three-dimensional graph of the mean yield and stability statistical rank along with their standard deviation was calculated.
Results: The results of this research showed that there is a high genetic diversity among the studied lines in fresh pod yield. The effects of genotype, year × location, location × genotype, and year × location × genotype were significant for the fresh pod yield trait, indicating that pod yield response was varied in different locations and that environments affected the lines differently. The means comparison results of two years and three regions showed that lines G9, G3, and G6 had the highest fresh pod yield per hectare. Lines G9 and G7 lines had the highest number of pods per plant and number of seeds per pod, and line G9 also had the longest pods. The results of AMMI analysis of variance showed that the effects of genotype, environment, and genotype-environment interaction were significant at the 1% level of probability. Notably, the first two components explained 81.1% of the genotype-environment interaction variation. These two components explained 66.2% and 14.9% of the variation, respectively. In the AMMI biplot analysis, lines G4, G7, G6, and G5 were the closest lines to the biplot center, so it can be said that they showed the least environmental changes and were recognized as stable lines of PachBaghela. Additionally, lines G8, G9, and G3, which are located at the top of the polygon, exhibited good specific adaptability with the regions of Rasht, Lahijan, and Shanderman. Consequently, they can be determined as selected genotypes for the studied locations. The results of the 16 stability statistics were different, therefore, to select the superior lines in terms of all statistics and appropriate yield, the mean and standard deviation of the statistical rank were used. The lines that had the lowest sum of the statistical rank (SR) the average statistical rank (AR) and the highest yield were selected as stable lines. Consequently, lines G6, G7, and G8 were identified as stable and superior lines.
Conclusion: According to the agronomic characteristics and the results obtained from the statistical methods, lines G7 and G6 were selected as PachBaghela lines with high-yield stability. If these lines are named and introduced into the agricultural sector as new improved varieties, they will increase farmers' income, increase production in the country, and consequently contribute to food security |