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Darvishzadeh R.,Urmia University | Alavi R.,Urmia Tobacco Research Center | Sarrafi A.,Laboratoire Of Biotechnologie Et Amelioration Des Plantes Bap
Journal of Crop Improvement | Year: 2010

Powdery mildew (Erysiphe cichoracearum DC.) is an important disease of tobacco (Nicotiana tabacum L.) in many countries. Losses in yield and quality have been reported to be around 30% to 80% in severe cases. Northwestern Iran is a hotspot for tobacco powdery mildew. To identify resistant genotypes, tobacco germplasm, including recombinant inbred lines (RILs) derived from the cross Basma S.31 × Dubec566, some Iranian landraces, and cultivars from different countries were evaluated under field conditions using a simple lattice design (10×10) with two replications. Each plot comprised 3 rows, 5 meters long. Spacing between rows was 65 cm and between plants within rows 20 cm. Susceptible line (Basma S.31) was planted throughout the experiment to guarantee homogeneous inoculation. The most resistant genotypes were 12 RILs (PD205, PD209, PD379, PD324, PD328, PD329, PD336, PD345, PD364, PD365, PD371, and PD381), three Iranian landraces (SPT413, Jahrom15, and Jahrom12), and cultivars (Basma104-1 and Pobeda1). Three cultivars (Kuklen6, Nevrokop261, and L17), two mutants (Mutant 2 and Mutant 3), and Matianus were included in the resistant group. The more resistant RILs (PD205 and PD209) were evaluated across three years and showed consistent behavior across years. Most genotypes studied were susceptible or highly susceptible to the disease. This information should be helpful in tobacco breeding programs. © Taylor & Francis Group, LLC. Source

Hatami Maleki H.,Islamic Azad University at Maragheh | Darvishzadeh R.,Urmia University | Sarrafi A.,Laboratoire Of Biotechnologie Et Amelioration Des Plantes Bap
Australasian Plant Pathology | Year: 2014

Black stem, caused by Phoma macdonaldii, is one of the most important diseases of sunflower in the world. Quantitative trait loci (QTLs) implicated in partial resistance to three isolates of P. macdonaldii including MA6, MP6 and MP10 were investigated using F2/F3 population from the cross between sunflower resistant mutant line 'M6-54-1' and susceptible inbred line 'ENSAT-B4'. A genetic linkage map was constructed with 88 amplified fragment length polymorphism (AFLP) and 44 simple sequence repeat (SSR) markers using 101 F2 individuals. The map comprises 17 linkage groups (LGs) with an overall length of 1,490 cM and mean density of one marker per 12.44 cM. Parental lines and their 101 F3 families were evaluated for their resistance to P. macdonalii isolates in controlled conditions in a randomized complete block design with three replications. High genetic variability and transgressive segregation were observed among F3 families for partial resistance to all of three P. macdonaldii isolates. Composite interval mapping analysis revealed 14 putative QTLs, localized on seven linkage groups, with phenotypic variance ranging from 4 to 42 %. The QTL bsrMP6.8.1 was detected as non isolate-specific QTL and the rest of them were 'isolate-specific' QTLs. The major QTL on LG8 which was involved in partial resistance to three isolates could be good candidate to introduce resistance to three P. macdonaldii isolates into elite sunflower breeding lines via marker assisted breeding program. © 2013 Australasian Plant Pathology Society Inc. Source

Darvishzadeh R.,Urmia University | Pirzad A.,Urmia University | Hatami-Maleki H.,Islamic Azad University at Maragheh | Kiani S.P.,Kansas State University | Sarrafi A.,Laboratoire Of Biotechnologie Et Amelioration Des Plantes Bap
Spanish Journal of Agricultural Research | Year: 2010

In this study, 21 genotypes of sunflower (Helianthus annuus L.) derived from a half diallel cross between six inbred lines were evaluated in both water-stressed and well-watered environments. In each environment, the genotypes were evaluated using a randomized complete block design with three replications. From the grain yield data, drought tolerance indices comprising of stability tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress susceptibility index (SSI), tolerance index (TOL), yield index (YI) and yield stability index (YSI) were calculated for every genotype. The resulting data were analyzed as obtained from a randomized complete block design. Significant differences among genotypes were observed for all drought tolerance indices except for SSI and YSI. High yield value in non-stress and stress environments was exhibited by genotypes 'LR4 × LR25' (14.02 g) and 'LR25 × C100' (3.84 g) respectively. The maximum value of STI (0.93), MP (8.72), GMP (6.91) and HM (5.48) indices was by genotype 'LR4 × LR25'. Correlation coefficients revealed that TOL, MP, GMP, STI, HM, and YI indices could effectively be used for screening of drought tolerant genotypes. Using MP, GMP, HM, TOL, YI and STI indices, genotypes UPGMA classification was done and three clusters were established that paralleled the biplot analysis results. According to results in this study, 'LR4 × LR25' is the most drought tolerant genotype which was clustered as group A. We suggest that tolerance indices including MP, GMP and HM are suitable for sunflower drought tolerant genotypes selection. Source

Darvishzadeh R.,Urmia University | Azizi M.,Urmia University | Hatami-Maleki H.,Islamic Azad University at Maragheh | Bernousi I.,Urmia University | And 3 more authors.
African Journal of Biotechnology | Year: 2010

Information about the genetic diversity and relationships among breeding lines and varieties is not only useful for germplasm conservation and inbred line identification, but also for the selection of parental lines for quantitative trait loci (QTL) mapping as well as hybrid breeding in crops, including sunflower. In order to develop mapping populations, genetic distances among twenty eight sunflower genotypes were evaluated using simple sequence repeat (SSR) markers. One hundred and two markers were generated by 38 SSR loci and the mean for the number of allele per locus was 2.32. Polymorphism information content (PIC) values ranged from 0.09 (locus ha3555) to 0.62 (locus ORS598) with an average of 0.41. Jaccard's coefficient similarity matrix for the studied sunflower genotypes varied from 0.25 to 0.9 indicating a broad genetic base. The maximum similarity (0.9) was observed between genotypes RT931 and ENSAT-R5, while the lowest similarity (0.25) was between genotypes LC1064C and LR64. Based on unweighted pair group method with arithmetic mean (UPGMA) clustering algorithm, the studied genotypes were clustered in four groups. However, some genotypes have the same specific characters that influence their clustering, and as a result, the results of the principal coordinate analysis (PCoA) largely corresponded to those obtained through cluster analysis. © 2010 Academic Journals. Source

Davar R.,University of Tehran | Darvishzadeh R.,Urmia University | Majd A.,University of Tehran | Ghosta Y.,Urmia University | Sarrafi A.,Laboratoire Of Biotechnologie Et Amelioration Des Plantes Bap
Phytopathologia Mediterranea | Year: 2010

Basal stem rot, caused by Sclerotinia sclerotiorum (Lib.) de Bary, is an important cause of yield loss in sunflower (Helianthus annuus L.). Quantitative trait loci (QTLs) implicated in partial resistance to basal stem rot disease were identified using 116 recombinant inbred lines (RILs) from the cross between the sunflower parental lines PAC2 and RHA266. The RILs and their parents were arranged in a completely randomized design with six replications and inoculated with a moderately aggressive isolate (SSU107) of S. sclerotiorum under controlled conditions. QTLs were mapped using a recently developed high-density simple sequence repeat/ amplified fragment length polymorphism (SSR/AFLP) sunflower linkage map. Analysis of variance showed highly significant differences among the sunflower genotypes for susceptibility to basal stem rot. The frequency distribution of genotypes for susceptibility to disease showed continuous patterns, suggesting that resistance is controlled by a polygenic system. Transgressive segregation for resistance occurred in this cross. Composite interval mapping analysis revealed 7 QTLs for percentage necrotic area, localized on 7 linkage groups. The effects of QTLs were small to moderate indicating a polygenic control of the studied character. However, like any other quantitative trait, it is necessary to confirm the position of the QTLs and to carry out fine-scale mapping before marker assisted selection (MAS) can be done. LG8 and LG16 are good candidates for further analysis to develop molecular markers for resistance to Sclerotinia disease. Source

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