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Showing 6 results for Pahlevani
Saeed Bagherikia, Mohammadhadi Pahlevani, Ahad Yamchi, Khalil Zenalinezhad, Ali Mostafaie,
Volume 4, Issue 1 (9-2017)
Abstract
Under drought stress conditions, as one of the most important limiting factors of grain yield in wheat at arid and semi-arid regions, the remobilization of assimilates gain would be more valuable to grain filling. There are a few reports on the importance of remobilization of the root during the grain filling period under drought stress conditions. An advanced mutant line of bread wheat (T-65-7-1) along with its wild type (cv. Tabasi), were planted at two moisture conditions (normal and 30-40% of field capacity) as a factorial experiment based on a completely randomized design with three replications. Sampling for gene expression analysis was conducted from the root in two stages (7 and 21 days after anthesis). In these genotypes, fructan remobilization, efficiency of fructan remobilization, and relative expression of genes involved in the synthesis and hydrolysis of fructan during the grain filling period, in root, were studied under terminal drought stress. The results showed that the stored fructan in the root participated in the assimilate remobilization. Higher fructan remobilization through root to grain in mutant line under drought stress conditions was due to over-expression of genes involved in the synthesis of fructan (1-SST and 6-SFT) at 7-days after anthesis and in hydrolysis of fructan (6-FEH) at 21-days after anthesis, compared to wild type. Drought stress did not cause a significant change in gene expression of 1-FFT and 1-FEH genes in the root of both genotypes, which confirms the only β (2,6) linkages as predominant form of fructan has affected under drought stress conditions. In wheat breeding programs, 1-SST, 6-SFT and 6-FEH can be used as molecular markers for selecting genotypes with high fructan content and more remobilization.
Arash Salami, Mohammadhadi Pahlevani, Khalil Zenalinezhad, Mohsen Esmaeilzadeh Moghaddam,
Volume 5, Issue 1 (9-2018)
Abstract
Collection and conservation of germplasm, particularly for landraces of important agronomically species and organizing their information, cause to continuity of their usefulness and reduce the risk of their genetic erosion. In this experiment, 10 Iranian wheat landraces along with the Chinese Spring cultivar, as control, were used to assess inter and intra populations variation by using ISSR molecular markers and morphological traits. Evaluation of populations in terms of height, spike length, awn length, number of spike nodes, number of grains per spike, flag leaf length and grain weight showed that there were considerable variation among landraces. Also, in some landraces like KhorramAbad and Ardabil, intra population diversity for some of these traits, such as plant height and length of awn, was obvious. Evaluation of the landraces for ISSR markers showed that among 99 scored bands, 78 bands were polymorphic. Percent of polymorphism with mean of 81.88 % was varied from 53.33 for primer of ISSR-4 to 100% for primers of ISSR-9, ISSR-14, ISSR-5 and ISSR-7. Average PIC of the landraces was estimated 3.0. Results of this study showed that there was considerable intra population diversity for the ISSR markers in landraces of KhorramAbad, Maragheh and Torbat-e-Heydarieh however, a little diversity for Khoy, Ahwaz, Isfahan, Mashad, Urmia, Shiraz and Ardabil was observed. Results of this study showed that there is inter and intra genetic diversity within Iranian landraces of wheat with different levels and these landraces can be used as basic population for extraction of pure lines.
Fatemeh Darvishnia, Mohammadhadi Pahlevani, Khalil Zaynali Nezhad, Khosro Azizi, Saied Bagherikia,
Volume 7, Issue 1 (9-2020)
Abstract
In order to determine the most effective indices for quantifying drought tolerance and identify genotypes that are tolerant to water stress in bread wheat, 50 bread wheat genotypes were compared in a randomized complete block design with three replications under both the non-stress dry farming with two complementary irrigation and the water stress dry farming conditions in Khorramabad, Iran. Analysis of variance showed that there was a significant difference among the genotypes in terms of all of the traits except the number of spike per area. In this study, eight indices including: Stress Tolerance Index (STI), Geometric Mean Productivity (GMP), Mean Productivity (MP), Yield Index (YI), Harmonic Mean (HM), Yield Stability Index (YSI), Stress Susceptibility Index (SSI), and Tolerance index (TOL) were calculated by using of seed yield of the genotypes under both conditions. Indices that selection based on them will improve the yield in both conditions, are considered as suitable index. STI, GMP, MP and HM were introduced as suitable index for drought resistance selection. Genotypes Shiroodi and S-90-5 were determined as the most appropriate based on 3D plot. Based on positive correlation between water stress resistance indices and yield under stress and non-stress environments, STI and GMP were the best indices. By using the Biplot method, Shiroodi, S-90-5 and Oroum genotypes were considered as high yielding potential genotypes under the both conditions. According to the results of cluster analysis, genotypes were classified into three groups based on drought tolerance indices. Graphical analysis of genotypes also showed that genotypes Shiroodi and S-90-5 were more profitable than others under both drought stress and non-drought stress conditions. These genotypes could also be used as parents caring desirable genes in the crossing programs and selection of tolerate genotypes.
Esmaeil Dasturani, Khalil Zaynali Nezhad, Masood Soltani Najafabadi, Mohammadhadi Pahlevani, Hassan Soltanlo, Saeed Bagherikia,
Volume 8, Issue 1 (8-2021)
Abstract
The aim of this study was to determine the haplotype groups and identify the specific alleles associated with desirable agronomic characteristics in bread wheat. For this purpose, 42 local bread wheat genotypes belong to Iran region and nine commercial cultivars along with Chinese Spring variety (reference genotype) were cultivated in the format of augmented design and evaluated based on their 13 phenotypic traits. The results of descriptive statistics showed that awn length and day to flowering had the highest and lowest phenotypic coefficient of variation, respectively. Eight microsatellite markers were used to investigate the haplotype variation of QTLs associated with phenotypic traits located on wheat chromosomes 4B and 7D. The result showed that the genotypes were classified into 13 and 6 haplotype groups according to the allelic comparison with the reference genotype on chromosome 4B and 7D, respectively. In order to investigate the relationship between traits and markers, analysis of variance was performed based on completely randomized design with unequal numbers of replications for each marker. In general, of the 13 traits studied, there was a statistically significant linkage for eight traits and for the three traits, an allele-specific was introduced simultaneously. If the breeders are interested in genotype selection that simultaneously have three desirable characteristics such as early anthesis, semi-dwarfing and a greater number of grains per spike, they can use an allele-specific (153 bp) of Xgwm149-4B marker.
Kaveh Sadeghi, Mohammadhadi Pahlevani, Mohsen Esmeilzadeh Moghaddam, Khalil Zaynali Nezhad,
Volume 8, Issue 2 (3-2022)
Abstract
Identifying selection indices is the most important step of a breeding project that aims to improve grain yield. The definition of the selection index is usually done by evaluating the variables in multivariate statistical methods. In the present study, the relationship between grain yield and its components in bread wheat genotypes was determined by multivariate statistical methods. The experiment was conducted in a randomized complete block design with 3 replications in the research farm of Gorgan University of Agricultural Sciences and Natural Resources in the 2018-19 crop years. Ten commercial cultivars of bread wheat along with their offspring from direct and inverse crosses in a dialysis arrangement were evaluated for morphological and phenological traits, especially grain yield and its components. The results of genotypic and phenotypic correlation coefficients showed a positive and significant correlation (at 1% probability level) between grain yield and spike length, spike weight, number of fertile tillers, number of seeds per spike, number of spikes per spike, 1000-seed weight, biological yield and harvest index. Based on the results of stepwise regression analysis, biological yield, harvest index, number of grains per main spike and main spike weight were entered into the regression model, respectively, and explained a total of 98% of the variation in grain yield. Based on the results of path analysis, biological yield had the highest direct effect on grain yield. After biological yield, the most direct effect on grain yield was related to the weight of main spike. Also, by considering eigenvalues greater than one in factor analysis, 8 hidden factors were identified that explained a total of 75.18% of the data changes. In general, it can be concluded that biological yield, harvest index, number of seeds per spike and weight of spike compared to other traits can be used as appropriate indicators in breeding programs to select high-yield genotypes in field conditions. Genotypes Alo, Ehsan♂ × Gonbad♀ and Ehsan had the highest value for the studied traits, which can be used in future breeding researches.
Ramezanali Pourali, Mohammadhadi Pahlevani, Khalil Zeinalnejad,
Volume 10, Issue 2 (2-2024)
Abstract
Increasing grain yield and improving the quality of bread are among the most important goals of wheat breeding programs in Iran. Understanding the genetic control of traits and finding molecular or morphological markers associated with them are also prerequisites for any genetic engineering program. In this study, 100 progenies of a 10 × 10 diallel cross were used to analyse the genetics of grain yield and bakery values using STS markers associated with HMWG subunits. This research was carried out during 2018 and 2019 cropping season at Gorgan University of Agricultural Sciences and Natural Resources experimental fields. In the first year, 10 wheat cultivars, including Gonbad, Morvarid, Kalate, Ehsan, Sirvan, Baharan, Chamran2, Shush, Mehrgan and Brat collected from different geographical regions of Iran were planted and crossed in the field. In the second year, the parents and crosses were planted in the form of a randomized complete block design with three replications. The grain yield, number of spikes per plant, number of seeds per spike, seed weight, days to emergence and plant height were recorded. The results of this study indicated significant genetic differences between the parents. Narrow-sense heritability analysis revealed that the crossing of cultivars is the best breeding method to enhance seed yield, number of spikes per plant and days to emergence. Also, to improve the number of seeds per spike, seed weight and plant height, classical breeding methods may offer higher efficiency. Marvarid and Gonbad were ranked 1st and 2nd, respectively with respect to general combining abilities for grain yield, attributed to their positive and significant general combining ability effects. The highest specific combining ability was observed for Ehsan×Gonbad, Marvarid×Chamran 2 and Shush×Sirvan crosses. The results of molecular markers analysis showed that the STS markers were able to identify the difference in the baking value of cultivars. The quality score of the cultivars ranged 6 and 10 and to this end, Kalate and Brat were the top cultivars. Therefore, due to superiority in terms of both quantity and quality for yield, these cultivars can be used as parents with desirable genes for future breeding programs. Overall, the STS markers employed in this study proved to be valuable markers for enhancing the genetic background of bread wheat, particularly when employing marker-assisted selection for bakery value.
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