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Showing 12 results for Rahimi
Reza Mir Drikvand, Goodarz Najafian, Mohammad Reza Bihamta, Asa Ebrahimi,
Volume 1, Issue 2 (2-2015)
Abstract
This study was conducted to identify markers associated with some kernel traits in bread wheat in two separate experiments under field and laboratory. One hundred wheat genotypes were evaluated in an alpha lattice experimental design with two replications. Grain hardness, seed length, seed width and thousand kernel weights were measured. Association mapping was performed based on 96 unlinked and 22 SSR QTL linked markers, using structure and Tassel software. Correction for population structure was performed using genome wide SSR markers so that genotypes were divided into six sub-populations. Totally, 35 SSR markers linked to traits were detected eight of them being QTL linked markers and other markers that were linked to traits, were used to investigate population structure. The QTLs linked markers were as follows: Chromosomes 5B, 5D and 6D had three QTL for grain hardness. Nine QTLs were detected on chromosomes 1A, 1B, 2A, 2B, 2D, 5B, 5D, 6D and 7B for kernel length, kernel width and thousand kernel weights. The results of this study demonstrate that association mapping is a useful approach to complement and enhance previous QTL information for marker-assisted selection in wheat.
Sedigh Ebrahimi, Abdolhossein Rezaei Nejad, Ahmad Ismaili, Farhad Karami,
Volume 1, Issue 2 (2-2015)
Abstract
Evaluation of genetic diversity among apricot genotypes may increase our genetic knowledge and provide better plant materials for selection of desirable genotypes. In this study, genetic diversity of 26 apricot genotypes phenological and physiological traits of 26 apricot cultivars collected at Kurdistan agricultural research station was studied based on a randomized complete block design with three replications for phenological and physiological traits. Analysis of variance showed that the effect of genotype on flower initiation, flowering period, relative water content (RWC), ion leakage, proline and potassium content of flower pistil tissue, spring frost damage to flowers, harvest date, total soluble solids, titratable Acidity (TA) and pH was significant at the 1% level. These results indicated that the existence of significant genetic variation among studied genotypes. The lowest heritability (28.5%) was belonged to date of 50% flowering, indicating the strong effect of environmental factors on this trait. The highest heritability (99%) estimated for related traits to yield including total soluble solids, fruit harvesting period and uniform rippening, suggested that the influence of environmental effects on these traits were very low.
Reza Mir Drikvand, Asma Khyrolahi, Asa Ebrahimi, Mohammad Rezvani,
Volume 2, Issue 1 (5-2015)
Abstract
In this study, genetic diversity of 25 rainfed bread and durum wheat genotypes were assessed using 20 SSR primers that all of them were generated scorable bands. Totally 69 alleles (ranged between 2 allele for Xcfd40 and Xgwm369, and 5 allele for Xbarc54 primers per each locus), were distinguished. Polymorphic information content (PIC) for all SSR primers was calculated. The highest (0.98) and the lowest (0.64) amount of PIC was pertained to Xcfd40 and Xgwm30 primers, respectively. Based on similarity matrix, the highest and lowest genetic similarity was belonged to Seri82 and Seri (0.86) and Sita/chil and Baviacora (0.14), respectively. Cluster analysis could distinct spring and winter wheat genotypes and as well as bread and durum wheat genotypes. It was concluded that SSR marker was suitable for evaluation of genetic diversity in rainfed wheat genotypes. This genetic diversity can be used in wheat breeding programs.
Mohammad Ali Ebrahimi, Rahim Mohammadian, Marouf Khalili,
Volume 3, Issue 1 (9-2016)
Abstract
Estimation of genetic variation in crops, a very important role in the development of breeding programs and preservation of genetic resources through morphological characteristics, is possible. To identifying genetic variation and double haploid barley lines classification in relation to germination traits, 72 lines derived from the cross of Steptoe and Morex were evaluated in randomized complete block design (RCBD) with two replications, at three conditions including normal and two salinity levels of NaCl (100 and 200 mM NaCl). Investigated traits in this study were coefficient of velocity of germination, final germination percentage, mean germination daily, germination rate index and average germination speed. The results indicated that considerable genetic variation among genotypes in all traits. Genetical correlation based on average of the three environments indicated that high significant correlation exist (r= 0.85**) between the daily germination and final germination percentage. In this study, the highest value of phenotypic and genotypic variation coefficient, broad and narrow sense heritability and genetic gain were calculated for final germination percentag. Based on cluster analysis, barley genotypes were grouped into three categories and genotypes of the third cluster, were superior coefficient of variation of germination, germination percentage, germination rate and mean daily germination index, but had low a mount of germination rate. Therefore, the genotype of this group can be used in breeding for high germination percentage. Using principle component analysis; five traits were grouped in the form of two new variables that explained 99.061 percent of the total variance. Analysis biplot indicated that the genotypes of first group have a high percentage of germination index and germination index coefficients.
Mehdi Ramezani, Mehdi Rahimi,
Volume 4, Issue 1 (9-2017)
Abstract
Ispaghula (Plantago ovata) is used to reduce gastrointestinal and urinary tract infections, as well as control blood glucose and cholesterol levels in the human body. The phylogeny and genetic diversity of 22 different ecotypes of Ispaghula were evaluated using 12 ISSR markers and nine morphological and phenological traits. Analysis of variance showed that there were significant differences among cultivars for all traits. Cluster analysis grouped 22 different ecotypes of Ispaghula in two groups using UPGMA method based on field data. The assessment of genetic diversity among ecotypes based molecular markers showed that the 12 primers amplified 91 polymorphic bands. The maximum number of bands (11) was produced by UBC813 and primers UBC811 with 10 bands were in the next steps, respectively. The minimum band number (4) was produced by UBC824. Polymorphism information content (PIC) value was varied from 0.26 to 0.45 and Marker index (MI) was varied from 0.90 to 4.13. Cluster analysis using UPGMA based on molecular markers, placed 22 ecotypes in the study in five groups, include 1, 1, 2, 3 and 15 ecotypes, respectively. Grouping of ecotypes with molecular markers was different with classification of the ecotypes based morphological traits. According to the results, ecotypes that are far apart can be used in the breeding program of Ispaghula.
Seyedeh Zahra Hosseini, Behroz Shiran, Mohammad Ali Ebrahimi,
Volume 5, Issue 2 (3-2019)
Abstract
Phylogenetic relations among 12 wild species of almonds, one cultivated almond and one species of peach were investigated by using of ITS1-5.8S rDNA-ITS2 sequences and trnL region of chloroplast DNA. To do this, maximum-parsimony and neighbor joining analysis adopted. Results of ITS data showed that studied species of Prunus only divided in two groups but incapable to separate different sections. P. tenella showed more diverse genetic distance in compare to other studied species and it seems that this species does not belong to Amygdalus. Also, by using the ITS data it can be reported that Prunus is monophyletic. In this research, the genetic distances for each pair of species were determined and the average genetic distance between species shows only the lowest genetic distance within the genus. Therefore, Prunus is a single genus. Regarding its high similarity of trnL region in wild almond species, it can be reported that maternal ancestor of Prunus is the same and trnL is not optimum marker to separate species of almond.
Mehdi Rahimi, Maryam Abdolinasab,
Volume 6, Issue 2 (3-2020)
Abstract
Biochemical and physiological traits are affected by environmental stresses and therefore the breeding of these traits will play an effective role in stress tolerance. In this study, hybrids of five S7 lines of maize in a 5 × 5 half-diallel design were investigated in order to study the combining ability of biochemical and physiological traits of maize at the Research Farm of Graduate University of Advanced Technology, Kerman, Iran during the 2017-18 crop year based on randomized complete block design with three replications. The results of analysis of variance by fourth Griffing's method showed that the general (GCA) and specific (SCA) combining ability variances were significant for protein, proline, sugar content, carotenoid, chlorophyll a, chlorophyll b and total chlorophyll traits. Therefore, the role of additive and non-additive effects was identified in controlling these traits. Protein, proline, chlorophyll a and total chlorophyll traits were more controlled by additive effects, whereas the carotenoid trait was more controlled by non-additive effects and the role of additive and non-additive effects in controlling other traits was almost equal. The KSC704-S7-11 line showed positive and significant general combining ability for most of the studied traits, suggesting this line can be used in breeding programs to improve and increase stress tolerance. In addition, P1 × P3 and P4 × P5 crosses showed the most positive and significant specific combining ability for proline, chlorophyll a, total chlorophyll and carotenoid traits; thus they can be considered as the best hybrids to improve and increase stress tolerance in corn.
Jamal Rahimi Darabad, Varahram Rashidi, Hossein Shahbazi, Mohammad Moghaddam Vahed, Ebrahim Khalilvand,
Volume 7, Issue 2 (3-2021)
Abstract
In order to determine the heritability and genetic parameters of some agronomic traits in barely (Hordeum vulgare L.) cultivars, a seven-parent half diallel (F1 crosses + parents) was conducted in the non-stress and salt stress (8 and 12 ds m-1) conditions in a randomized complete block design with three replications. Genetic analysis was performed by Hayman’s method and Griffing’s fixed model, method 2. The slope of linear regression of Wr on Vr were significantly higher than 0 and had not significant difference with 1 indicating the additive-dominant model was satisfied in all cases. The narrow-sense heritability of traits was medium to high (0.4-0.8) but their broad-sense heritability was estimated relatively high (0.7-0.9). Results of regression graphs showed that Afzal parent had the most dominant allele. The significance of “a” component in most of the studied traits indicated the presence of the additive effects in controlling of traits. The significance of “b” component in most of the studied traits indicated the presence of the dominance effects in controlling of traits. The proportion of positive and negative genes was lower than 0.25 in all of the traits (except for grain weight per spike in 12 ds m-1 salinity), indicating the presence of asymmetry in the distribution of the positive and negative alleles in the parents. Based on general combining ability effects, it was concluded that under salinity, cultivar “Kavir” had favorable alleles in plant height, grain weight per spike and 100 grain weight traits and can be used as a general parent in breeding programs. Estimates of high broad-sense heritability and narrow-sense heritability in most traits indicated that these genetic materials were promising for breeding under normal and salinity stress conditions.
Mehdi Rahimi,
Volume 7, Issue 2 (3-2021)
Abstract
The diallel mating design is an important tool used by plant breeding programs to obtain information on trait inheritance. Knowledge of gene action, heritability and genetic advance from selection is a prerequisite for starting a breeding program for developing varieties of maize. Five maize S7 lines and their F2 progenies were studied in a 5 × 5 half-diallel crossing design to evaluate the gene action and the heritability of biochemical and physiological traits. Parents and their F2 hybrids were planted in a randomized complete block design with three replications at the Research Farm of Graduate University of Advanced Technology (Kerman, Iran) in 2017 cropping year, and chlorophyll (Chl), proline, protein, carotenoid and reducing sugars traits were evaluated. Analysis of variance showed significant differences among genotypes for the studied traits at 1% probability level. The graphical results of Hayman's analysis showed the role of over-dominance genes effects in controlling proline content, sugars content, Chl a, Chl b, total Chl and carotenoids traits whiles the protein content trait was controlled by the incomplete dominance of genes. The narrow-sense heritability for carotenoid and proline content traits were 0.14, for protein content was 0.44 and for other traits were varaied in this range. The results of this study showed that the use of heterozygosity and the production of hybrid varieties can be used to breeding traits such as proline content, sugars content, Chl a, Chl b, total Chl and carotenoids. However, for breeding of protein content, use of both methods (selection and production of hybrid) are proposed.
Jawed Rahimi, Fatemeh Amini, Hossein Ramshini, Mahyar Abedi, Mahmood Lotfi,
Volume 9, Issue 2 (3-2023)
Abstract
Tomato is the second most important vegetables, after potato, which has the highest area of cultivation worldwide. Acording to FAO statistics, Iran is the sixth producer of tomato cultivation in the world. However, more than 95 percent of vegetable seeds are imported into the country. The present study was conducted in order to evaluate commercial imported hybrids (8320, Eden, Matin and Xaman) and the F2 and F3 generations resulting from their self-breeding. In this regard, after the production of F2 and F3 generations, three generations (F1, F2 and F3) together with the control variety (Early Orbana y) were evaluated in the research farm of Seed and Plant Improvement Institute, Karaj, Iran, based on a randomized complete block design with four replications during 2019-2020. The analysis of variance showed that the difference among genotypes for single plant yield, days to flowering, average single fruit weight, number of fruits harvested and acidity (pH), was significant at the level of 1% probability and total soluble solids (TSS) was significant at the level of 5%. The results of the mean comparison showed that the highest mean of single plant yield belonged to 8320 F1 (10920/10g), the highest days to flowering was observed in Xaman F2 (47.01 days), the highest mean weight of single fruit was observed in Xaman F1 (115.50 g), the highest number of fruits harvested was in Xaman F1 (106.62), the highest amount of total soluble solids was in Matin F3 generation (4.96) and the lowest amount of acidity (pH) was in 8320 F1 (4.10). The results of estimating genetic parameters showed that most of the evaluated traits had high genetic and phenotypic variances, but a slight difference was observed between the coefficient of phototypic variation and the coefficient of genotypic variation, which indicates a small effect of environment on the control of these traits. Higher variance of dominance than additive variance in most traits caused the degree of dominance to be greater than one, Therefore, the possibility of control of traits by genes with dominance or over-dominance effects is high, and in order to improve these traits, the methods for hybrid development are suggested.
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.
Mohammad Nader Ebrahimi, Hadi Ahmadi, Mostafa Darvishnia, Daryoush Ghoudarzi,
Volume 10, Issue 2 (2-2024)
Abstract
Wheat fusarium head blight (FHB) is one of the most important diseases of wheat in humid and hot regions of the world,which causes a decrease in yield and grain quality. Fusarium head blight is caused by Fusarium graminearum. In order to investigate the resistance of some wheat traits against FHB, 27 varieties and lines of bread wheat were sown in autumn of 2021 at the farm of Faculty of Agriculture, Lorestan University. The spikes were infected at the first flowering stage by spray inoculation. The results showed that there was a great diversity among the 27 varieties of bread wheat tested in terms of growth traits, yield components, and grain yield. The results of simple correlation and also stepwise regression analysis showed that the traits of 1000 seed weight, plant height, number of seeds per spike, number of spikes, spike length and plant height are very important traits for grain yield. According to values of broad sense heritability and genetic gain for plant height and high correlation of this trait and seed yield, plant height can be used as a suitable trait for improving seed yield by selection. The overall results showed that Shiraz, Pishtaz, Quds and Morwarid-2 cultivars are suitable for transferring resistance to wheat spike blight disease in breeding programs.
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