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Showing 25 results for Cluster Analysis
Mahmood Aslanparviz, Varahram Rashidi, Mansour Omidi, Alireza Etminan, Alireza Ahmadzadeh,
Volume 8, Issue 2 (3-2022)
Abstract
Evaluation of genetic diversity is the key principal for plant breeding, providing an opportunity to discover novel characters and alleles for breeders. In the present study, 69 durum wheat genotypes were investigated for genetic diversity using several inter-simple sequence repeat (ISSR) markers. Sixteen ISSR primers amplified a total of 163 fragments, which out 160 fragments were polymorphic. The mean values of polymorphic information content (PIC), resolving power (Rp) and marker index (MI) indicated that the used ISSR primers could be exploited for further assessing relationships among investigated genotypes and population structure analysis. The results of the molecular analysis of variance showed that the genetic variation within populations is more than between them. Based on genetic variation parameters, the highest number of observed alleles (Na), Shannon’s information index (I) and the percentage of polymorphic loci (PPL) were found in Iranian landraces. Cluster analysis and population structure grouped all investigated genotypes into three main clusters and six subpopulations, respectively. In conclusion, our results revealed the high rate of genetic diversity within Iranian landraces, so this germplasm can be used as a valuable gene source for the selection of parent lines and use of them in durum wheat breeding programs.
Soheila Afkar, Faranak Hadi, Ali Ashraf Jafari,
Volume 8, Issue 2 (3-2022)
Abstract
Festuca is one of the largest genera of the grass family, which has more than 600 species with different ploidy levels. The aim of this study was to estimate the genetic diversity within 22 populations of three species of Festuca (Festuca arundinacea, F.rubra and F.ovina) using a seed storage protein electrophoresis pattern. These species showed a significant variation in the number of protein bands from 5-13. The highest number of bands was found in G17 (F.rubra) and the lowest number of protein bands was in G5 (F.ovina). Band number 14 was only observed in G3. It is suggested that this band can be considered as a specific band for the identification of this genotype. According to the results of AMOVA analysis, there is a high level of genetic diversity within the species rather than between species that can be due to the out-crossing nature of this genus. According to observed differences for variation parameters among the three studied species, it is concluded that they have dissimilar genetic structures. The results of cluster analysis based on seed storage protein profiles in evaluated genotypes using Euclidean distance matrix and UPGMA method showed four groups. The lowest similarity coefficient was between G14 and G15 (F.arundinacea) with G6 (F.ovina). Hence, it is suggested that they evolved from a different evolutionary process and it is suggested to use them as the parents of new synthetic varieties. The observed diversity in the seed protein pattern in the three species of Festuca, can be explained by allogamy-induced-heterozygosity, species difference or population collection from various regions.
Shahla Hosseini, Mohammad Reza Rahgozar, Hedieh Badakhshan,
Volume 8, Issue 2 (3-2022)
Abstract
Genus Allium L. contains very taxonomically complex sections, especially the subgenus Melanocrommyum. The systematic position of the species in each section has been revised many times over time. In the present study, the relationship between 32 ecotypes belonging to 10 different species of Allium was investigated using ISSR markers. The nine primers used produced 166 polymorphic bands (average 18 bands per primer). Among the primers used, ISSR873 primer with 27 bands made the most, and ISSR4 primer with two bands had the lowest polymorphic bands. The PIC of the markers ranged from 0.04 to 0.43. Cluster analysis by UPGMA method based on molecular markers divided the studied ecotypes into four groups. The clustering and principal coordinate analysis results showed that most morphologically similar species were grouped in closed clusters. According to Dice similarity coefficient, the highest percentage of similarity was shown between Allium stipitatum and Allium saralicum ecotypes (72 percent) from the Melanocrommyum subgenus, and the lowest similarity was obtained between Allium tripedale and Allium iranicum ecotypes (12 percent). The ecotypes with the lowest similarity percentage belong to the subgenus Allium and Nectaroscordum, which are placed in separate clusters. Based on the results, the ecotypes of Pseudoprason, Melanocrommyum, and Procerallium sections showed the highest affinity. In general, it can be concluded that ISSR markers are useful for classifying Allium species and have sufficient potential for phylogenetic studies of species. In addition, due to significant genetic diversity among the studied ecotypes of wild Allium species, this diversity can be used in future breeding programs of crop.
Ahmad Kaab Omeyr, Payam Pourmohammadi, Abdolali Gilani, Khalil Alami-Saeid, Mohammad Fakhari,
Volume 8, Issue 2 (3-2022)
Abstract
Various strategies have been developed to reduce water consumption in rice cultivation, including rice cultivation in water-saturated soil, drying and wetting of the soil (periodic irrigation), and aerobic rice cultivation. In this study, in order to identify and grouping rice cultivars suitable for aerobic cultivation, 34 cultivars of native and improved rice cultivars were selected and evaluated. Factor analysis based on principal components analysis based on all traits showed that 6 factors were extracted with special values of more than one. These 6 factors, after the Varimax rotation, justify the 6 main and independent factors, justifying 78.08% of the total variation. In the first harvest, cluster analysis using WARD method, cultivars were grouped into 4 groups, which cluster 3 being the largest cluster. Discriminant analysis of first harvest, showed that all cultivars were grouped correctly. In canonical discriminant the first two canonical functions with eigenvalues greater than one explained a total of 88.9% of the variance. In cluster analysis based on the average of the data obtained from Raton product, genotypes were divided into two different groups. The genotypes of the first group were higher than the genotypes of the second group in terms of yield and yield components and were introduced as superior genotypes. Heritability with genetic improvement for leaf area duration, number of seedling (grown plants), number of spikes per unit area, number of full seeds and degree of maturity showed that these traits can be transferred to hybrid offspring and selections based on these traits are effective.
Davood Kiani, Gholamreza Ghodrati, Sadollah Mansouri,
Volume 9, Issue 1 (9-2022)
Abstract
Sesame is an important crop plant for harsh environmental conditions because it is relatively resistance to drought stress. Evaluation of different genotypes in different climate condition plays a fundamental role in selection of the best genotypes before the commercial release of a variety and helping in identify plant traits that should be monitored during breeding experiments. In the present study, 10 promising lines obtained from the preliminary yield test were investigated to evaluate the yield compatibility along with 6 local cultivars in a randomized complete block design experiment with three replications in two cropping years (2018 and 2019) in Dashtestan climate condition in Bushehr province. During the growing season, phenology traits, grain yield components and grain yield were measured. Based on the results of ANOVA, statistically significant difference was observed between different genotypes for plant height, height of the first sub branch, height of the first capsule, number of sub branches, number of capsules per plant, length of capsule, length of capsule bearing zone, number of seeds in capsule and grain yield. Based on the mean comparison and biplot analysis the genotype 12 (Local Dashtestan), 2 (SES97-103), 7 (SES97-110) and 15 (Local Jiroft), were identified as superior genotypes for grain yield. Genotype 5 (SES97-105) and genotypes 14 (SES97-124) with 104.5 days and 4 (Local Darab1) with 111 showed the highest and lowest number of days to maturity, respectively. First capsule height showed the highest positive and significant phenotype (0.56) and genetic (0.78) correlation with grain yield. Days to the end of flowering and days to physiological maturity traits showed a negative genetic correlation with yield. Cluster analysis separated 16 sesame genotypes into four separate groups. Based on regression analysis, the height of the first capsule was identified as the most sensitive trait in predicting the yield of sesame genotypes in Dashtestan region in Bushehr province, which seems it can be considered during breeding programs.
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