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Showing 4 results for Biplot
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.
Seyedeh Zahra Hosseini, Ahmad Ismaili, Seyed Sajad Sohrabi,
Volume 5, Issue 2 (3-2019)
Abstract
Drought is a threaded factor in the world production and application of breeding methods could improve the tolerant and adapted cultivators under drought stress condition. In order to evaluate and determine the stress tolerance indices and identifion of tolerant genotypes to drought stress, 15 safflower genotypes were evaluated in a randomized complete block design with three replications in two conditions (stress and non-stress). Analysis of variance showed significant differences among genotypes for all traits, stress tolerance indices and yield in both conditions. Significant positive correlation was found between grain yield in the stress condition with indicators stress tolerance index, harmonic mean and geometric mean productivity indicating that these indices are suitable criteria for screening drought tolerant genotypes. No significant correlation was observed between Ys with tolerance index and mean productivity, hence they can be discarded as the desirable markers for identifying drought tolerant genotypes. In conclusion, using a graphical approach of three dimensional scatter plots, Principal component analysis and biplot analysis, two tolerant genotype (Syrian and Kino-76) were selected for future programs in stress and non-stress condition.
Shaghayegh Mehravi, Gholam Ali Ranjbar, Hamid Najafi-Zarrini, Ghader Mirzaghaderi,
Volume 7, Issue 1 (9-2020)
Abstract
Anise is an annual plant belonging to Apiaceae family and fruit essential oil of this herb is used in various pharmaceutical, cosmetic and beverage industries. Drought stress is one of the most critical limiting factors for anise production in worldwide. In this research, to finding interrelationships among different traits and performance, some anise genotypes were evaluated using the biplot method. In this study, 18 anise genotypes were evaluated in normal irrigation regime and drought stress conditions according to a randomized complete block design with three replications at the field of the Western Australia University (UWA), Australia. Fifteen phonological, morphological and physiological traits were measured. Results indicated the positive and significant correlations between yield and fruit number and fruit thousand weight in both conditions. Due to the negative correlation between phonological features with fruit yield in two different irrigation conditions, it could be concluded that to have genotypes with high fruit yield, selection for early ripening genotypes should be done in anise. In this study, a significant correlation was observed between fruit yield and relative water content in the stress condition. Therefore, this trait can be used as a physiological index to evaluate drought tolerance in anise. According to cluster analysis based on the measured traits, genotypes were divided into 3 groups in both non-stress and stress conditions. According to the results of the comparison of the means of the groups in non-stress and drought stress conditions, genotypes No. 1, 5, 6, 11, 12, 14, 15 and 16 were identified as the most drought-tolerant genotypes. These genotypes could be utilized in breeding programs for further improvement of drought tolerance in anise germplasm.
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.
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