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Mozhgan Shirinpour, Ehsan Atazadeh, Ahmad Bybordi, Saeid Aharizad, Ali Asghari, Ashkboos Amini,
Volume 10, Issue 1 (9-2023)
Abstract
Considering the importance of maize production and the impact of water deficit stress on reducing the yield of maize, estimating the genetic components and heritability of traits for determine the breeding method under water deficit stress is essential in breeding programs. The generations drived from a cross between two inbred lines of maize including B73 (maternal line) and MO17 (paternal line), SC704 (F1) as well as F2, BC1, BC2 and F3 generations in order to estimate the genetic effects and heritability of yield, yield components and morphological traits were studied. Seven maize generations using the generations mean analysis under the full irrigation, mild and severe water deficit conditions were evaluated. The experiment was conducted in the form of randomized complete block design with 20 replications per experimental unit during two cropping seasons (2018-2019) at the Agricultural Research Station of University of Tabriz. The results of two-year combined analysis of variance and mean comparisons under three different irrigation regimes showed that water deficit stress significantly reduced all of the studied traits (except root/shoot ratio). The generations mean analysis showed the high contribution of non-additive gene effects for the genetic control of grain yield, ear diameter, number of kernel row, ear weight (in full irrigation conditions), 100 grain weight, plant height, fresh shoot weight and biological yield traits. According to these results, selection in the advanced generations and the breeding method based on hybridization can be effective to improve these traits. Also, the significant contribution of additive gene effects in controlling the inheritance of ear length, ear weight (in both stress conditions) and root/shoot ratio traits indicated that selection in early segregating generations and inbred parents can be effective for breeding of these traits and taking advantage of additive variance. Hybrid SC704 and inbred MO17 compared with the inbred B73 showed the lowest variation percentage under the water deficit stress conditions, which indicated their high yield potential and stability in the stress conditions.
Maryam Ebrahimi, Reza Darvishzadeh, Amir Fayaz Moghaddam,
Volume 10, Issue 1 (9-2023)
Abstract
Protection of food security is one of the basic priorities of any country, which is achieved through the development and introduction of new, high-yielding and stress-resistant crop varieties. Considering the wide range of usage; human nutrition, livestock and poultry nutrition as well as use in industrial products production, maize is of special importance in agricultural development programs. To improve a trait with complex behavior and low heritability, indirect selection by other traits or a suitable index developed based on several traits can be used. In this research, 86 maize genotypes were cultivated in the form of randomized complete block design with three replications in the field in the Faculty of Agriculture, Urmia University under two normal and salt stress conditions. The measurement of the traits was done from the tassel appearance to kernel physiological maturity. In order to speed up genotype selection and increase the acuracy of selecting high yielding genotypes, four selection indices including Smith- Hazel, Pasek- Baker, Brim and Robinson were used and calculated. The results of present study revealed that selection based on the Smith- Hazel index with the highest selection efficiency (∆H) will increase the grain yield in normal and grain yield and plant height in salt stress conditions. This index, with its high correlation with the breeding value is introduced as a superior index. Based on this index, R59 and 6*/88 genotypes were introduced as the superior genotypes under normal and salt stress conditions, respectively. Nonetheless, these genotypes were recognized as the best genotypes considering the results of all other investigated indices. Identifying and introducing genotypes tolerant to salinity stress is of particular importance due to the expansion of saline lands and the limitation of access to water suitable for irrigation. Based on the above results, 6*/88 genotype is recommended for the development of promising hybrids for cultivation in areas with water or saline soil.
Seyedeh Somayeh Mousavi, Omidali Akbarpour, Dr Tahmasb Hosseinpour,
Volume 10, Issue 1 (9-2023)
Abstract
In this research, 15 bread wheat genotypes along with Aftab variety as a control variety were implemented with 4 replications in the form of randomized complete block design for 3 crop years (2016-2019) at Sarab Chengai Station in Khorramabad. The likelihood ratio test (LRT) showed that the genotype-year interaction effect was significant for grain yield. Based on this, singular value analysis (SVD) was performed on the matrix of best linear unbiased predictions (BLUP) of genotype × year interaction to evaluate the stability of genotypes. The scree plot showed that the first principal component accounted for 71.7% and the second principal component accounted for 28.3% of the matrix changes resulting from the best unbiased predictions of the genotype interaction per year. The biplot of the first principal component of the environment against the nominal yield also showed that genotypes No. 9, 12 and 13 had a negligible contribution to the genotype × year interaction and had higher general stability. Also, the biplot of grain yield against the weighted average of absolute scores (WAASB) placed the genotypes in four regions, so that genotypes No. 15, 16, 12, 11, and 10 are in the fourth region due to high stability (low values WAASB) and magnitude of response variable (high performance) were identified as superior genotypes. The WAASBY index (weighted average of WAASB stability and performance) identified genotypes No. 15, 16, 12, 10, 11, 14, 9 and 4 as stable and high yielding genotypes. In general, based on WAASB and WAASBY indices and their comparison, genotypes 15, 16, 12, 11 and 10 were selected as the best genotypes that can be recommended for cultivation in similar climates.
Nasrin Akbari, Siamak Alavi Kia, Mostafa Valizadeh,
Volume 10, Issue 2 (2-2024)
Abstract
Due to world population incline and the increasing wheat consumption as human main staple food, as well as high amount of waste of bread which is mainly due to its low quality, the wheat breeding programs to improve bread quality are of great importance. Therefore, evaluating the wheat grains quality and the genetic variation of bread-making quality traits among lines derived from crosses becomes imperative. To this end, the gliadin protein banding pattern of 28 recombinant inbred lines, their corresponding parents and 10 other commercial cultivars were examined via A-PAGE method. The variation between and within the lines and cultivars was determined using AMOVA according to the protein bands. The results of this study revealed high variation for gliadins coding loci with total mean of 73.96%. The percentage of polymorphism was estimated to be 91.67 and 56.25 for lines and commercial cultivars, respectively. The minimum and maximum number of gliadin bands were 12 and 25 bands, respectively. Also, based on PhiPT statistics, the significant difference was observed (P<0.05) between commercial cultivars and recombinant inbred lines in terms of gliadin banding patterns. Cluster analysis and PCoA via banding pattern of gliadins led to formation of three and four distinct groups, respectively. The highest variation was observed in ω-gliadins, suggesting that they may have a role in observed variation among genotypes and their bread making-quality traits.
Nasrin Akbari, Reza Darvishzadeh,
Volume 11, Issue 1 (9-2024)
Abstract
Sunflower, one of the important oilseed plants, is affected by drought stress, consequently leading to yield decreases. Direct selection for improving seed yield, as the end product of multiple traits, is often ineffective due to the significant impact of environmental conditions. For many years, indirect selection through other traits or selection indices has been proposed to improve seed yield. In the present experiment, 100 oilseed sunflower genotypes were evaluated in terms of some agro-morphological traits using a simple 10 × 10 lattice design under normal and drought stress conditions during two consecutive croping seasons. In drought stress conditions, irrigation was applied after 180 mm of evaporation from class A evaporation pan, compared to 90 mm in normal irrigation conditions. Brim, Smith-Hazel, Robinson and Pesek-Baker selection indices were calculated to select genotypes under two environmental conditions. In order to evaluate and compare the efficiency of selection indices and select the best index, the genetic gain of traits (∆G), expected gain (∆H) and relative efficiency of selection index (RE) were calculated. The results of this study showed that the direct response to selection for the traits including kernel oil content, days to maturity and leaf length under both environmental conditions was more favorable compared to the correlated response. However, for head and stem diameter traits, the lowest efficiency of direct selection was observed under both environmental conditions compared to other investigated traits. Considering the two criteria; the genetic gain of traits (∆G) and expected gain (∆H) under normal and drought stress conditions, the two indexes of Brim and Smith-Hazel were introduced as the best index and the genotype ENSAT-254 was introduced as the superior genotype. The selected ENSAT-254 genotype can be considered in developing hybrid cultivars for cultivation under drought stress conditions, provided it is validated at the molecular level by analyzing the expression of genes related to water deficit stress tolerance.
Fatemeh Bagherzadeh, Hannaneh Mirahmadi, Soraya Pourtabrizi, Ali Kazemipour, Maryam Dorraninejad, Roohollah Abdoshahi,
Volume 11, Issue 1 (9-2024)
Abstract
Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat in many parts of the world. Genetic resistance is the best way to deal with this disease. This disease evolves very quickly, and for this reason, the resistance of many major-effect resistance genes has been overcome. In this study, the Yr5 and Yr15 genes, which are among the most effective resistance genes in a full-grown plant stage, were introduced to the Iranian cultivars, including Baharan, Rakhshan, Setareh, Sivand, Parsi, and Amin using the marker-assisted backcrossing method. These genes were intrroduced to the mentioned cultivars in six distinct breeding projects. Cultivars were crosses with the donor parents Yr5/6*Avocet‘S’and Yr15/6*Avocet‘S’. The progeny of F1 generation, were backcrossed with the Iranian cultivars (recurrent parent) to obtain BC1F1 progeny in each population. By genotyping 30 random plants in each project, the heterozygous genotypes carrying the resistance genes were identified using specific markers, and the second backcrossing was performed. Overall, the results of this studuy demonstrated that within each population, a stripe rust-resistant line can be developed through repeated generations of backcrossing followed by one generation of selfing. The introduction and pyramiding of yellow rust resistance genes into the Iranian cultivars not only enhance durable resistance and mitigate yield losses during epidemic years but also can contribute to benefits to the environment.
Hossein Mehripour Azbarmi, Jalal Saba, Bahram Alizadeh, Amir Gholizadeh, Farid Shekari,
Volume 11, Issue 1 (9-2024)
Abstract
The genotype × environment interaction is a major challenge in studying quantitative characters because it reduces grain yield stability in different environments. In this regard, to analysis the genotype × environment interactions and to determine the yield stability of winter rapeseed mutant lines, 9 lines and 6 cultivars were evaluated in a randomized complete block design with three replications in six experimental field stations (Esfahan, Hamedan, Karaj, Kermanshah, Qazvin and Zarghan) during 2021–2023 croping seasons. The combined analysis of variance indicated that the effects of environments, genotypes and genotype × environment interaction were significant, suggesting that the genotypes responded differently in the studied environment conditions. So, there was the possibility of stability analysis. According to the stability analysis results using the Eberhart and Russel method, the Talaye cultivar with higher grain yield than overall mean and regression coefficient equal to one (bi=1) was identified as the genotype with high general stability for all regions. Based on the simultaneous selection method for yield and stability (YSi), the lines Z-900-6, T-1200-1, and Talaye cultivar with the lowest values were stable, whereas Zarafam, Okapi and Express cultivars with the highest values were unstable. Also, based on the SIIG index, the lines Z-900-6, T-1200-1, and Talaye cultivar with having high SIIG values as well as higher grain yields that total average was recognized as superior genotypes from the point of stability and grain yield. According to the results of cluster analysis, Karaj, Zarghan, Kermanshah and Isfahan locations were located in a group that indicates these locations had high predictability and repeatability power.
Behnaz Seifolahpour, Sohbat Bahraminejad, Kianoosh Cheghamirza, Shahryar Sasani,
Volume 11, Issue 1 (9-2024)
Abstract
Wheat is regarded as one of the most important cereal crops and a fundamental food staple worldwide. Bread is the primary and the main product of wheat, and its optimal quality is crucial for enhancing taste, extending shelf life, and reducing waste. In this study, some genetic parameters associated with the grain quality characteristics of 131 F6 lines resulting from the cross of Marvdasht × Nurstar cultivars (along with parents) were evaluated by measuring traits including grain protein content, moisture, starch, neutral detergent fibers (NDF), falling number, total gluten, strong gluten, weak gluten and dry gluten. The results of this study showed that the lines had highly significant differences only for grain protein content and Falling number. Results indicated that some lines had higher values than parents for important traits such as grain protein content. The results of the cluster analysis confirmed the diversity between the lines. Group five with 31 lines showed the highest mean for grain protein content. Protein content showed a significantly positive correlation with gluten-related traits. The lowest and highest values of phenotypic, genetic, and environmental variation coefficients were obtained for starch percentage and falling's number, respectively. The significant difference between the coefficient of genetic and phenotypic changes in traits such as grain starch and gluten indicate the greater influence of the environment on the traits. Protein and falling numbers had high heritability and genetic advancement. According to the results of this study, due to their high diversity and minimal environmental influence, the grain protein content and falling number traits can be used as selection criteria for superior lines (28, 35, 81, and 100).
Smaeil Talebi Kouyakhi, Bahram Maleki Zanjani, Mostafa Modarresi, Alireza Tarang,
Volume 11, Issue 1 (9-2024)
Abstract
Global food security is endanged by various factors, with one of the most significant being the quantitative and qualitative increase in agricultural production. Given the vital role of rice in the daily nutrition of Iranians and the necessity to enhance the efficiency of limited land resources, it is imperative to increase the yield per unit area. Identifying genotypes carrying alleles of genes associated with grain yield improvement is one of the methods to breed rice plant. Therefore, breeding rice genotypes can be used in breeding programs, to produce high-yield varieties. Given the importance of the number of grain per panicle and its impact on increasing rice grain yield per unit area, this study aimed to screen rice genotypes using a functional marker associated with the Gn1a gene, among several genes related to yield. In this research, 52 localraces and improved genotypes of rice were obtaied from the collection of the Rice Research Institute of Iran. The grain number trait was evaluated based on phenotypic and molecular evaluations in the field related to the band pattern amplified by gene specific primer pairs for Grain number 1a gene (Gn1a), controlling the grain number trait. The genetic evaluation identified 15 cultivars with the allele associated with a large panicle (more than 121 grains per panicle) and 37 cultivars without this allele. This finding, confirmed by phenotypic evaluation, demonstrates the reliability and accuracy of the marker used to predict and differentiate cultivars for upcoming breeding programs. The logistic regression results also supported this outcome. However, several other examined samples exhibited a high number of seeds, indicating the presence of additional genes influencing the seed count per panicle in those lines.
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