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Azimzadeh M.,University of Tehran | Amiri R.,University of Tehran | Davoodi-Bojd E.,University of Tehran | Soltanian-Zadeh H.,University of Tehran | And 2 more authors.
Spanish Journal of Agricultural Research | Year: 2010

In plant and animal breeding, the best individuals are selected for the next breeding cycle based on the selection index computed from observed phenotypic values of several traits. However, in calculating the selection index, large amounts of data must be analyzed which is still performed by a calculator. This can cause imperfections in the breeding procedures. In this paper an automatic method for simulating a population under natural selection is proposed based on the selection operator of the genetic algorithms. The fitness function of the algorithm is a linear combination of the individual traits imported by the user. The algorithm generates both general and detailed scores of each trait for each labeled individual. The individuals are sorted with respect to their general scores and it is possible to extract individuals whose general scores are greater than a threshold defined by the user. The outlier individuals can also be eliminated. Moreover, for improved illustration and comparison, the individuals are displayed in a graph based on their index values. The proposed algorithm was applied to two distinct dataset and shown that results of the two methods coincide. The proposed method is automatic, fast, and free of human mistakes. Therefore, it is expected to improve the breeding procedures, especially when the numbers of individuals and traits are huge. Source


Stevanato P.,University of Padua | Trebbi D.,University of Padua | Norouzi P.,Sugar Beet Seed Institute | Broccanello C.,University of Padua | Saccomani M.,University of Padua
International Sugar Journal | Year: 2012

The productivity of sugar beet is strongly limited by several biotic stresses. These include rhizomania (induced by beet necrotic yellow vein virus, BNYVV) that causes yield losses of 20-50% or more. The only way to control this disease is the use of resistant varieties. Rz1 is the major resistance gene present within commercial sugar beet varieties. A linkage analysis was carried out on F2 individuals to identify single nucleotide polymorphism (SNP) markers linked to Rz1. From the 384 SNPs evaluated, three SNPs (SNP1, SNP2 and SNP3) resulted tightly linked to Rz1. Linkage analysis confirms that the Rz1 gene is located on chromosome 3 and is flanked by two closely linked markers named SNP1 and SNP2 with genetic distances of 0.7 cM and 5.2 cM, respectively. The SNP3 is located at 8.9 cM. These first reported SNPs provide a valuable basis for marker assisted introgression of Rz1 resistance to rhizomania. Source


Amiri R.,University of Tehran | Sarafraz E.,University of Tehran | Sadat noori S.A.,University of Tehran | Norouzi P.,Sugar Beet Seed Institute | Seyedmohammadi N.,University of Tehran
Romanian Agricultural Research | Year: 2011

Monogermity is a character that is controlled by one pair of recessive allele in sugar beet. This character is used in many breeding projects. If the character is tagged with molecular markers, it will be possible to easily distinguish monogerm and multigerm plants by DNA extraction followed by PCR analysis in seedling stage. Bulked segregant analysis using 297 RAPD primers in an F 2 population of a hybrid between monogerm and multigerm sugar beet accessions was performed for identification of RAPD marker linked to monogerm gene. DNA of 10 plants from multigerm and monogerm plants were separately mixed. At first, the primers were tested on DNA bulks and then on individual plants of the bulks. When the polymorphism of the primers was confirmed, they were tested on other individual plants. Eventually, two coupling and three repulsion markers were identified in F2 population, which their distances to monogerm gene were lower than 50 cM. OP-S 4-2000r marker was the nearest marker to monogerm gene. The distance of between this marker and monogerm locus was estimated to 6.1 rf. Source


Norouzi P.,Sugar Beet Seed Institute | Sabzehzari M.,University of Tehran | Zeinali H.,University of Tehran
Journal of Crop Science and Biotechnology | Year: 2015

Sugar beet (Beta vulgaris L.) is one of the two major products supplying sugar (sucroses) in the world. Rhizomania is one of the most destructive diseases of sugar beet world-wide. Holly is the major source of resistance to rhizomania. The objectives of this study were to identify the dominant homozygous genotypes resistant to rhizomania using ZN1 molecular marker, to field evaluate S1 progenies of plants already proved to be containing the marker and also to determine the relationship of this and other SCAR (sequence characterized amplified region) markers with SNP1 (single nucleotide polymorphism) marker associated with the Rz 1 gene. Molecular analysis was carried out on 27 O-type populations (consisting of 13 susceptible and 6 resistant genotypes). Field evaluation and scoring of the phenotypic traits including greenness, growth, uniformity and disease score of 12 O-type populations were carried out on a rhizomania-infested field. The percent agreement of coupling marker ZN1 and repulsion marker ZN8 with disease score was 0.91 and 0.93, respectively. Although all O-types had the Rz 1 resistance gene but the phenotypic differences were observed due to the effect of different genetic backgrounds and modifier genes. Overall, the results showed that the selected markers can be used for marker-assisted selection (MAS) to reduce the time and cost of breeding programs and increase the efficiency of selection. © 2015 Korean Society of Crop Science and Springer Science+Business Media Dordrecht. Source


Mahmoudi S.B.,Sugar Beet Seed Institute | Ghashghaie S.,Islamic Azad University at Tehran
Euphytica | Year: 2013

Interactions of 17 sugar beet lines and cultivars with four isolates of Macrophomina phaseolina (the causal agent of charcoal rot) and one isolate of Rhizoctonia solani (the causal agent of crown and root rot) were studied in separate experiments under greenhouse conditions. The isolates of Macrophomina were taken from their host plants, sugar beet (two isolates), soybean and sesame. In the first experiment, the colonized toothpick was used as inoculum. In the second experiment, six-month-old sugar beet plants were inoculated with barley seeds colonized with M. phaseolina. For the inoculation of sugar beet lines with R. solani, the colonized corn seeds were used. Root symptoms were recorded four weeks after inoculation, by estimating the proportion of the root surface infected by the pathogens, using a 1-9 standard scale. Our results showed a significant difference among lines and cultivars in their resistance to these two pathogens. Line B8618 was found to be considerably resistant to the isolates of the both pathogens. The inoculation methods of Macrophomina isolates had no significant effect on the results. The interaction between isolate and cultivar was not also significant in Macrophomina-resistant lines. Therefore, it appears that the response of sugar beet lines to the tested fungal isolates was not differential. These resistant lines showed a high resistance to all the tested M. phaseolina isolates. Our results revealed that the Macrophomina-resistant lines also showed resistance to R. solani. Furthermore, the sugar beet drought tolerant lines (M293, M362 and M345) were susceptible to the tested M. phaseolina and R. solani isolates. © 2012 Springer Science+Business Media Dordrecht. Source

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