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Mahmodi F.,University Putra Malaysia | Kadir J.B.,University Putra Malaysia | Puteh A.,University Putra Malaysia | Pourdad S.S.,Dry land Agricultural Research Institute DARI | And 2 more authors.
Plant Pathology Journal | Year: 2014

Genetic diversity and differentiation of 50 Colletotrichum spp. isolates from legume crops studied through multigene loci, RAPD and ISSR analysis. DNA sequence comparisons by six genes (ITS, ACT, Tub2, CHS-1, GAPDH, and HIS3) verified species identity of C. truncatum, C. dematium and C. gloeosporiodes and identity C. capsici as a synonym of C. truncatum. Based on the matrix distance analysis of multigene sequences, the Colletotrichum species showed diverse degrees of intera and interspecific divergence (0.0 to 1.4%) and (15.5-19.9), respectively. A multilocus molecular phylogenetic analysis clustered Colletotrichum spp. isolates into 3 well-defined clades, representing three distinct species; C. truncatum, C. dematium and C. gloeosporioides. The ISSR and RAPD and cluster analysis exhibited a high degree of variability among different isolates and permitted the grouping of isolates of Colletotrichum spp. into three distinct clusters. Distinct populations of Colletotrichum spp. isolates were genetically in accordance with host specificity and inconsistent with geographical origins. The large population of C. truncatum showed greater amounts of genetic diversity than smaller populations of C. dematium and C. gloeosporioides species. Results of ISSR and RAPD markers were congruent, but the effective maker ratio and the number of private alleles were greater in ISSR markers. © The Korean Society of Plant Pathology. Source

Safavi S.A.,Islamic Azad University at Tehran | Pourdad S.S.,Dry land Agricultural Research Institute DARI | Taeb M.,Islamic Azad University at Tehran | Khosroshahli M.,Dry land Agricultural Research Institute DARI
Journal of Food, Agriculture and Environment | Year: 2010

Genetic variation in twenty safflower (Carthamus tinctorius L.) accessions was characterized by means of agro-morphological traits, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) markers in order to evaluate. A field trial was conducted to evaluate 17 agro-morphological traits. To study RAPD and ISSR, initially, 53 primers were screened, of which 22 produced reproducible amplification products. Using 13 selected RAPD primers 74 markers were generated of which 60 were polymorphic (81.08%). The number of amplified bands varied from three to nine, with size ranged from 250 to 2,500 bps. The nine selected ISSR primers produced 50 bands across 20 genotypes, of which 48 were polymorphic (96.00%). The number of amplified fragments with ISSR primers ranged from three to eight and varied in size from 250 to 1,450 bps. By all primers (RAPD + ISSR), a total of 124 bands were detected, of which 108 bands (87%) were polymorphic with an average of 5.63 bands per primer. High percentage of polymorphism (87%) observed with combined markers data revealed high level of genetic variation existing among the accessions. Genetic relationship estimated using similarity coefficients (Jaccard's) values between different pair of accessions varied from 0.26 to 0.84 in RAPD, 0.28 to 0.86 in ISSR and 0.29 to 0.78 with combined markers suggested a variation (dissimilarity) ranging from 16 to 74%, 14 to 72% and 22 to 71% respectively. ISSR markers were relatively more efficient than the RAPD assay. The Mantel matrix correspondence test between two Jaccard's similarity matrices, showing statistically significant correlation between ISSR- and RAPD-based similarities. Cluster analysis based on combined data of both molecular markers (ISSR+RAPD) separated the accessions into five groups and based on morphological traits, RAPD and ISSR data accessions formed in four distinct groups. Classification schemes generated by morphologic and molecular markers data did not coincide. The grouping of accessions was supported by principal coordinate analyses (PCoA). It is suggested that ISSR and RAPD are effective markers system for detecting variation among safflower genotypes. Source

Jamshidmoghaddam M.,Dry land Agricultural Research Institute DARI | Pourdad S.S.,Dry land Agricultural Research Institute DARI
Euphytica | Year: 2013

Evaluation of genotype × environment interaction (GEI) is an important component of the variety selection process in multi-environment trials. The objectives of this study were first to analyze GEI on seed yield of 18 spine safflower genotypes grown for three consecutive seasons (2008-2011) at three locations, representative of rainfed winter safflower growing areas of Iran, by the additive main effects and multiplicative interaction (AMMI) model, and second to compare AMMI-derived stability statistics with several stability different methods, and two stability analysis approaches the yield-stability (Ysi) and the GGE (genotype + genotype × environment) biplot that are widely used to identify high-yielding and stable genotypes. The results of the AMMI analysis showed that main effects due to genotype, environment, and GEI as well as first six interaction principle component axes (IPCA1 to 6) were significant (P < 0. 01). According to most stability statistics of AMMI analyses, genotypes G5 and G14 were the most stable genotypes across environments. According to the adjusted stability variance (s2), the high-yielding genotype, G2, was unstable due to the heterogeneity caused by environmental index. Based on the definition of stable genotypes by regression method (b = 1, Sd 2 = 0), genotypes G11, G9, G14, G3, G12 and G13 had average stability for seed yield. Stability parameters of Tai indicated that genotype G5 had specific adaptability to unfavorable environments. The GGE biplot and the Ysi statistic gave similar results in identifying genotype G2 (PI-209295) as the best one to release for rainfed conditions of Iran. The factor analysis was used for grouping all stability parameters. The first factor separated static and dynamic concepts of stability, in which the Ysi and GGED (i. e., the distance from the markers of individual genotypes to the ideal genotype) parameters had a dynamic concept of stability, and the other remaining parameters had static concept of stability. © 2012 Springer Science+Business Media B.V. Source

Moghaddam M.J.,Dry land Agricultural Research Institute DARI | Pourdad S.S.,Dry land Agricultural Research Institute DARI
Euphytica | Year: 2011

Partitioning of the genotypes by environment interaction (GEI) is important in order to determine the nature of the GEI. The objectives of this study were to assess the presence and nature of GEI for nine agronomic traits of rapeseed cultivars, and to identify cultivars with favorable levels of stable oil production. Nine rapeseed cultivars, including seven open pollinated and two hybrids, Hyola308 and Hyola401, were grown in ten environments under rain-fed warm areas of Iran. The GEI was significant for all traits and was partitioned into components representing heterogeneity due to environmental index and the remainder of the GEI. Among the all traits with a highly significant heterogeneity, the largest amount of heterogeneity removed from the GEI was for seeds per pod and seed weight. We found GEIs for both oil content and seed yield were largely influenced by differences in correlations among pairs of cultivars (86.8 and 71.4% of the GEI sum of squares, respectively), suggesting that crossover GEIs (i. e., change in genotype rankings among environments) are present. The mean correlation of each cultivar with all other cultivars (r̄ ii') ranged from 0.53 to 0.83 for oil content and 0.86 to 0.96 for seed yield. A comparison was done of the significance of Sh-σ i 2 (stability variance derived from total GEI) and Sh-S i 2 (adjusted stability variance derived from residual GEI) assignable to each genotype for oil content and seed and oil yield. Based on Sh-σ i 2, three cultivars were unstable for oil content, whereas six cultivars were unstable for seed and oil yield. The removal of heterogeneity revealed that one unstable cultivar for oil content and three unstable cultivars for oil yield were judged to be stable. All cultivars with (r̄ ii') ≤ 0.63 were labeled unstable for oil content, whereas all with (r̄ ii') ≤ 0.94 were considered unstable for seed yield. The relationships between (r̄ ii') and Sh-σ i 2 were significant (P < 0.01) for oil content and seed yield. The results of rank correlation coefficients showed significant positive correlations of Yield-Stability statistic (YS i) with oil content and oil yield. Cultivars such as Option500 and Hyola401 were identified as having stable, high levels to seed yield and oil content. © 2011 Springer Science+Business Media B.V. Source

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