جستجوی مقالات مرتبط با کلیدواژه « molecular marker » در نشریات گروه « زراعت »

Chickpea (Cicer arietinum L.) with a high amount of protein and valuable minerals, is considered one of the important items in the Iranian food basket. Due to its adaptability to the harsh climatic conditions of the country's drylands, it is grown in 500,000 ha of rain-fed and dry areas of Iran.  It is considered as the most important county’s rainfed legume crop and because of its rotation cultivation with cereals, plays an important role in the sustainability of agriculture in these areas. Yellowing and wilting disease caused by Fusarium oxysporum f.sp. ciceris is one of the most important diseases of the plant worldwide. The disease causes a quantitative and qualitative decrease in the production of the crop in all areas of the country. The most effective and economical method of managing and controlling the disease is the production and use of resistant cultivars.

In this study, 92 infested farms with suspected plants showing symptoms of yellowing and wilting were visited in the northwest and west of the country. The detailed characters of the samples were recorded. Subsequently, they were transferred to the laboratory and the pathogen was isolated from the host, purified and their pathogenicity on a susceptible chickpea variety was verified. For identification, in the first step, classical methods based on morphological characteristics and taxonomic keys were used, while in the second step, molecular techniques were applied.

Based on classical methods, all samples were characterized as a species of Fusarium genus (Fusarium spp.). Based on taxonomic and morphological methods, 39 isolates were identified as F.oxysporum. Subsequently, by using a molecular marker, the belonging of 32 isolates to the special form (forma specialis) of chickpea was confirmed. In the final step, using specific markers, 15 isolates were identified as races 1B/C, 2, 4 and 6. These results indicate the existence of races 2 and 4 among the collected samples, which is the first report of their presence in Iran. These findings can be used in the production of disease-resistant cultivars for the infested areas of the country.

Fusarium wilt (FW) caused by F. oxysporum f. sp. ciceris causes extensive damage to chickpea in many parts of the Iran. The technique of Marker-assisted backcrossing (MABC) is one of the effective and accurate methods in transferring specific genes such as disease resistance genes in a short time in self-pollination plants. Hashem is one of Iranian chickpea cultivars with high yield, plant height and tall stems which its cultivation is limited due to susceptibility to the fusarium wilt. Therefore, Purpose of this study was to introgression resistance to fusarium wilt from Ana cultivar, as a donor, to Hashem as a recurrent and susceptible cultivar using molecular marker-assisted backcrossing.

This research was conducted during five cropping seasons (2018-2023). Crossing was done between the selected parents of chickpea cultivar Ana (as a donor parent) and Hashem (as a recurrent parent) and the F1 progeny was backcrossed with Hashem to produce the BC1F1 generation. By using three backcrosses and one rounds of selfing, BC3F2 progeny was obtained. Foreground selection (FGS) was conducted with four markers (TA59, TA96, TR19, and CaM1402) linked to FW resistance genes. Background selection (BGS) was employed with evenly distributed 16 (Ana × Hashem) SSR markers in the chickpea genome to select plant(s) with higher recurrent parent genome (RPG) recovery. Finally, the selected lines of BC3F2 generation were phenotypically evaluated in terms of Fusarium disease resistance.

In first year, from the crossing of two parents, 20 real F1 plants were obtained and backcrossed with Hashem to produce BC1F1 plants. Based on results of foreground selection (FGS), was undertaken using four markers (TA59, TA96, TR19, and CaM1402) linked to resistance genes, 6 BC1F1 plants contained 4 resistant alleles and participated in the second backcrossing to produce BC2F1 plants. In the following, from a total of 52 BC2F1 plants 12 BC2F1 plants contained 4 resistant alleles, for background selection (BGS) to observe the recovery of recurrent parent genome using 16 SSRs, At this stage based on the BGS results 5 plant, with the highest background recovery, selected and backcrossed with recurrent parent to produce BC3F1 plants. Followed by cycles of, 6 plants in BC3F1 containing resistant genes and most similar to the recurrent parent were selected. The identified plants were selfed to obtain 6 BC3F2 lines which were screened phenotypically for resistance to fusarium wilt. Finally, 12 BC3F2 lines were obtained which led to identification of 3 highly resistant lines of Hashem with FWR gene introgressed in them. Also, in this study using Meta-QTL analysis region associated with genetic resistance to different race of fusarium wilt were identified on chromosomes 2, 4, 5 and 6.

In rice, the use of male sterility is a prerequisite for the commercial exploitation of heterosis. Two well established male sterility systems in rice are cytoplasmic genetic male sterility (CMS), a three-line system, and environmentally sensitive genic male sterility (EGMS). EGMS has two types of mechanisms: PGMS and TGMS. TGMS lines are sterilized when they are at a temperature above 25-30°C during the cluster and flowering stages. In order to accelerate the development of TGMS lines in various genetic fields, marker-assisted selection (MAS) can increase the speed and accuracy of this transmission. The aim of this study was to identify the chromosomal location of the gene controlling the sterility trait TGMS and the SSR marker associated with this gene in Nemat TGMS cultivar.

 For this study, Nemat TGMS cultivar was crossed with Fajr cultivar to obtain F2 and BC1 populations for genetic studies. After DNA extraction from 142 genotypes and PCR, the results observed in F1, F2 and BCF1 generations clearly indicated that the TGMS trait in TGMS is controlled by a recessive gene. For this study 14 SSR markers were used to determine the marker correlated with TGMS gene. The frequency of recombination between markers and TGMS locus was estimated using maximum likelihood, assuming that all individuals were completely sterile in terms of TGMS homozygous location. Linkage between marker loci and TGMS QTL was tested by chi square (χ2) test and LOD score.

Among the markers, RM110 and RM29 primers had a high correlation with TGMS gene (5.74 and 11.63 cM, respectively). Various markers have been reported by researchers for the TGMS gene on chromosome 2.

The use of mutation in sterilization (TGMS) and variation in cultivar genotype has led to different markers being reported even for a particular gene. The use of markers that have a high correlation with this trait (MAS) can facilitate the transfer of TGMS gene to other cultivars.

Rhizomania is the most destructive disease in spring sugar beet along with root-knot nematode and are spreading in some parts of Iran. The best control method against these two diseases is using resistant cultivars. Therefore, the aim of this study was to develop and select a high yield hybrid resistant to rhizomania and root knot nematode. Twenty-seven full-sib families (S1) from SB-34 origin which screened with molecular markers for rhizomania and root knot nematode resistance gene, were used to develop double resistant hybrids. In the spring of 2015, vernalized families were crossed to one single cross (7112*SB-36) in separate isolates. In summer, S1/S2 seeds from the paternal plants and three-way cross hybrid seeds from maternal plants were harvested and cleaned. Out of 27 isolates, only 19 isolates had adequate seeds from both parental lines. In autumn of the same year, selected hybrids were planted in greenhouse in Karaj. Seedlings were analyzed by SCAR and SNP markers linked to rhizomania and root knot nematode resistance genes to determine gene frequencies in hybrids. Based on the results of molecular evaluation, 14 hybrids were selected. In the spring of 2016, selected hybrids along with some controls, overall 20 varieties, were planted in two rhizomania-infected areas in Khorasan Razavi and Fars based on randomized complete block design with six replications. Roots were harvested in autumn and qualitative and quantitative characteristics such as root yield, sugar content, and white sugar yield were measured. Data were analyzed using SAS 9.1.3 software. According to the results of field trials and the frequency of rhizomania resistance gene and root node nematode in the laboratory, hybrid SB36*(7112*930620) with 10.92 t/ha white sugar yield to be used.

Saffron is a triploid and sterile plant having no or little genetic variation. Mutation induction is a way of increasing genetic diversity in vegetatively propagated plants. The first step in the mutation induction is to perform a radio-sensitivity test for determining the proper dose of gamma ray. Therefore, the aim of this study was to test the sensitivity of different doses of gamma ray in two conditions of cold and non-cold treatment of saffron corms. For this purpose, a factorial experiment with two factors including cold pre-treatment (cold and non-cold) and different doses of gamma ray (0, 5, 10, 15, 20 and 25 Gy) was conducted in a randomized complete block design with three replications. Growth and morphological characteristics such as plant height, number of leaves per plant, leaf dry weight, sprouting rate and percentage in the first year (MV1), and attributes related to daughter corms and flower yield, such as mean height of the stigma and dry weight of the stigma in the second year (MV2) were measured. The results of the study showed that the effect of cold treatment, radiation and their interaction was statistically significant, with the increase in gamma dose, most of the traits decreased significantly compared to the control. The radio-sensitivity test for the mean of plant height and sprouting rate and percentage, corm weight in two levels of pre-cold treatments showed that 50% survival was in the range of 15±2 Gray. According to the radio-sensitivity test, the number of leaves per plant was less susceptible to gamma rays. In order to study the genetic diversity of the gamma-irradiated saffron. The mutated samples of saffron were evaluated using RAPD and ISSR molecular markers. Cluster analysis was performed using the UPGMA method for both marker systems. The results showed that there was polymorphism between the control samples and radiated samples. In general, the results showed that the RAPD and ISSR markers could detect the polymorphic mutants and identify saffron mutants.

This study was performed to screen 35 commercial potato cultivars and 24 promising clones for resistance to Potato virus X (PVX) using biological and molecular marker assays. To purify and propagate the virus, infected potato samples were inoculated on common globe amaranth (Gompherena globose) and then on tobacco and maintained under in vitro conditions. The reaction of genotypes to PVX were evaluated based on International Potato Centre (CIP) standard method by mechanical inoculation and grafting under the greenhouse conditions. In mechanical experiment, three plants of each genotype were inoculated and the resistant genotypes were identified based on virus detection by ELISA. To determine the type of resistance, the resistant genotypes were grafted on tomato cv. Rutgers plants infected with PVX in three replications, and their infection by virus was examined using DAS-ELISA, 21 days post inoculation. The results of both experiments showed that 12 commercial potato cultivars and 11 promising clones were extremely resistance (ER) to PVX. Moreover, nine commercial potato cultivars and one promising clone showed hypersensitive resistance (HR) reaction. Twenty-six genotypes showed infection to PVX, at least in one replication, and considered as susceptible to the virus. In addition, resistance genes, Rx1 and Rx2, were successfully amplified in resistant genotypes using specific primers 5RX1 and 106RX2, respectively. However, no PCR product could be detected in the PVX susceptible and HR genotypes which were in accordance with the results of biological assays. Finally, Rx1 and Rx2 genes were detected in 13 and seven potato genotypes, respectively. It was concluded that genotypes carrying Rx1 and Rx2 genes can be used in potato breeding programs to develop new potato cultivars with desirable agronomic characteristics and resistance to PVX.

In this study, the genetic diversity of 22 bread wheat cultivars was investigated through microsatellite markers and physiological traits under controlled condition. For this purpose an experiment was implemented via those varieties with four treated levels of cold stress (8 (control), +2, 0, -2 Celsius) in factorial arrangement in a randomized completely block design (RCBD). Results of variance analysis showed the effects of interaction between cultivars spring cold levels is signification at the 1% probability of error level. According the results of trait Proline content in -2ºC, The highest level of this trait belongs to Moqane2 and the Golestan was the lowest one. Fructan content, Also in this level of cold stress, showed Ohadi and Dez cultivars, respectively. To investigate the genetic diversity at the molecular level were used from 21 microsatellite primer pairs. The 11 pairs of them could show good polymorphism and totally identified 19 alleles. The mean number of produced alleles was 2.27 alleles per marker locus and the range of alleles at loci was 1 to 4. The polymorphic information contents (PIC) values of the loci had ranged from 0.09 t0 0.98 with average 0.62. Results of stepwise regression, shows the significant relationship 2 markers, Xgwm174 Proline-related traits in intense stress condition and Xgwm642 with fructan-related In terms of control.

Milk Thistle (Silybum marianum L.) is a plant from the Asteraceae family that has high therapeutic properties due to its secondary metabolites, such as silymarin. Considering the significant therapeutic effects of this plant and the necessity of its cultivation in Iran, evaluation of its genetic diversity is important for breeding purposes. In the present study, the genetic relationship of eight milk thistle accessions was studied using CDDP and SCoT markers. Based on the results of the molecular evaluation, a total of 62 detectable bands were obtained from seven selective SCoT primers, of which 53 polymorphic band (85.48%) were found, while from the seven CDDP primers, a total of 58 detectable bands were obtained, of which 50 bands were polymorphic (86.2%). The mean polymorphic information content index (PIC) obtained from CDDP and SCoT markers were 0.39 and 0.23, respectively. Both the CDDP and SCoT markers showed more variation between accessions than within accessions. The high level of genetic diversity observed in the studied accessions can be used in milk thistle breeding programs.

IntroductionSunflower (Helianthus annuus L.) is one of the most important crops grown mainly for edible oil. Sclerotinia sclerotiorum (Lib.) de Bary is a common and widespread pathogen of sunflower. Sclerotinia stem rot is one of the most damaging diseases of sunflower in world, causing average yield reductions of 10 to 20%. It causes total production loss under favorable environmental conditions. Hence, plant improvement projects must focus on creating of new genotypes with higher resistance against diseases. Resistance to S. sclerotiorum (Lib.) de Bary has been described as quantitatively inherited with additive and dominant gene effects. Identification of chromosome regions controlling partial resistance to sclerotinia stem rot can increase understanding about the genetic control of the diseases and developing cultivars with improved partial resistance. In this study, retrotranposon-based molecular markers associated with resistance to disease as well as some important agromorphological traits identified using general and mixed linear models in Tassel software.
Materials and MethodsA collection of 100 sunflower lines, kindly provided by several research centers in Europe, Iran and the United States, were evaluated using a 1010 simple lattice design with two replications. Each plot comprised 2 lines 5 m long, with a spacing of 65 × 25 cm between lines and plants, respectively. The experiment was conducted in 2015 at a farm in ‘Vaghaslo-e-Sofla’ village on Urmia. Five plants per genotype in each replication were inoculated with a fungal isolate collected from naturally infected sunflower plants of this farm in previous year.Some resistant and agronomical traits including percentage of necrotic area after 4, 8, 12 days inoculation, 100 seeds weight of non contaminated plants, 100 seeds weight of contaminated plants, yield per plant in non contaminated plants, yield per plant in contaminated plants, 100 seeds weight loss, and per plant yield loss were measured. The genetic profile of population was prepared with 28 rerotransposon markers.
Results and DiscussionBased on molecular marker data, the studied association panel was subdivided into two subpopulations (K=2). Association analysis using mixed linear model (MLM) identified 27 loci significantly (P

Fennel (Foeniculum vulgare Mill.) is one of the well-known medicinal and aromatic plants. To determine variability between 16 Iranian Fennel landrace based on molecular markers, this experiment was conducted in the biotechnology laboratory of Payame Noor University of Kermanshah in 2014. In this experiment, 16 landrace of the Foeniculum vulgare Mill. were selected from the Natural Resources Gene Bank of Iran of Research Institute of Forest and Rangeland. Landrace were evaluated based on 15 SCoT primers markers. All of the SCot primers showed 77 visible bands in which four bands were similar patterns. The SC5 and SC29 primers had the most number of bands with 10 and 9 bands respectively, while SC10, SC26 and SC44 with two bands showed the least band numbers. The Polymorphic information content (PIC), marker index (MI), EMR and RP indices were calculated for all primers. With this point of view, SC15 and SC63 were the best primers to identify variability among these Fennels. Total genetic similarity based on these primers was 66 percent. The greatest genetic similarity was between Ardabil1 with Ardabil2 and Tehran2 landrace. The lowest genetic distance was between Ghazvin and Yazd fennel landrace. Cluster analysis based Jakard coefficient by UPGMA was classified all genotype to four groups and this clustering was confirmed by principal coordinate (PCo) and analysis of molecular variance (AMOVA). Portion of between group variance was just 24 percent of total variance.

O-type lines have an important role in sugar beet breeding as their cross with CMS lines results in male-sterile single cross production which can be used as female in cultivar development. In this study, thirty-six O-type lines resistant to rhizomania disease were produced from two breeding populations. Lines were evaluated for rhizomania resistance in Zarghan station, Fars province using a randomized complete block design with four replications. At harvest, roots were scored for infection to rhizomania. At the same time, genotypes were evaluated for the presence of resistance gene using molecular marker. Among O-type lines, lines 32302 and 32304 had lower scores than imported resistant check cultivar and in total, 18 lines together with two parental lines and resistant check cultivar were placed in one group. Gene presence percentage for resistant and susceptible check cultivars was 92 and 0%, respectively. There was 65% association between gene presence and average disease infection score of genotypes.

In order to evaluate drought tolerance and genetic variation in barley genotypes based on morpho-physiological traits and molecular markers, an experiment carried out in split plot based on randomized complete block design (RCBD) in three replications. Main factor was the different levels of irrigation included continuous irrigation as control, 2/3 and 1/3 continuous irrigation and secondary factor included 18 barley genotypes. Analysis of variance showed considerable variation among genotypes for the measured traits. Also, the Genotype×Stress interaction had significant effect on grain number per spike, protein content, proline content, carotenoid content, chlorophyll a, b and yield. In ISSR markers analysis 9 primers used that were totally produced 61 bands, where 50 bands were polymorphic. The mean PIC and MI indices were obtained for all primers were 0.46 and 2.6, respectively. High value of these indices showed high performance of certain primers for synchronized analysis of more bands. At current study, primer 2 with PIC index of 0.57 was the best primer for evaluation of genetic variation amon the studied barley genotypes. At well watered level (control), the highest significant correlations found between markers and morphological traits related to P5L5 and the highest correlation among markers and physiological traits were related to P16L2 markers. At 2/3 well watered condition the highest significant correlations between markers and morphological were related to P5L5 and P9L5, and also among marker and physiological traits belonged to P13L4 and P5L5 markers. According to cluster analysis, the genotypes were classified into four clusters. The first clusters included three genotypes Licivi, Sahand and FA1-2. Also, the genotypes F-GRB-84-11,F-GRB-85-5,PALLIDUM48//NORDIC…¡.GLORIA-BAR/COPAL//.., Dasht and Sahra were located in second cluster and third cluster containing genotypes CHAMICO/TOCTE// CONGONA (a), CHAMICO/TOCTE//CONGONA(d) CONGONA/BORR and the other genotypes were located in the fourth cluster. Overall of indices and studied traits, it seems that among the studied genotypes the genotypes STIPA/PETUNIA//KOLLA/BBSC (a) and CHAMICO/TOCETE//CONGONA (a) for irrigated areas and the Sahand genotype for rainfed areas are suitable genotypes.

Saffron is a triploid، sterile plant، used as a spice and medicinalplant in all countries. Stigma is the most important part of saffron. So far no reliable molecular methods were provided to identify and prediction of the three/multi branches species. In this study، using different bioinformatics algorithms، new tools for prediction based on Sequence-Related Amplified Polymorphismmolecular markers is presented. Five alleles M1311400، M151200، M12100 and M10850 selected as the most important classifier by Attribute Weighting models which has the potential to cluster and recognize the three from multi branches stigma. K-Means and K-Medoids unsupervised clustering algorithms were fully able to cluster each genotype to the right classes. Our results showed that for the first time، data mining techniques can be effectively used to genetic differentiation between three and multi stigma with above 90 percent the accuracy andprecision. These methods can use in gene mapping and selection by biomarker.

In order to increase beet cyst nematode resistance gene frequency, one population named 261*(20314*W-1009) that contains Hs1pro-1 was used in present research. In first year, the population was planted in selection plotes in field. Single plants were labeled and leaf samples were prepared. Then DNA extraction from leaves was done and molecular analysis of plants containing resistance gene accomplished using STS marker and specific PCR test. In second year, gall signs onto resistant vernalized roots were noted and the roots were planted under cages in isolated plots to produce S1 seeds.The S1 seeds were sowed in greenhouse for molecular analysis and in the steckling field to produce the roots. The roots were vernalized in the field in winter season. The molecular results of the S1 plants by Hs1pro-1 marker showed that presence of the resistant gene among the S1 lines is varied 25 to 63 percent. In third year, the vernalized roots were planted under cages in isolated plots to produce new S1 seeds. The new S1 seeds were grown in greenhouse for molecular analysis. The molecular results of the new S1 plants by Hs1pro-1 marker showed enhancement of the resistant gene among the S1 lines that varied 39 to 80 percent. The results showed that resistance gene frequency can be increased by increasing in selfing number and genotypic selection by molecular marker.

Simple sequence repeats (SSR) polymorphism in citrus including male sterile, sterile, low fertile and fertile was examined by analyzing 28 representative accessions sampled from north of Iran. Fifty four polymorphic alleles with an average of 4.2 alleles per primer were detected from eight pairs of used primers. The lowest number of alleles was observed in TAA27, CTT01, CCSM18 and ATC09 loci with only three alleles and the highest number of alleles was observed in TAA15 locus with eight alleles. Polymorphic information content (PIC) values changed from 0.34 (AG14) to 0.90 (CCSM18). Genetic similarities among accessions were calculated according to Jaccard Similarity Index and used to construct a dendrogram based on the unweighted pair group method using arithmetic averages (UPGMA) which put the 28 samples into four major groups (A, B, C and D). The cultivars of male sterile Satsuma mandarin were clustered into group A; those of orange, grapefruit and Page (a complex hybrid) into group B; mandarin cultivars into group C; and lemon Lisbon into group D.

Rhizomania is the most important disease of sugar beet in Iran and some other parts of the world, and plays an essential role in decreasing sugar yield in fields. The best approach to control this disease is to use resistant varieties. Tagging the resistance genes in breeding programs, by molecular markers is necessary. In this study, some breeding populations and commercial varieties of sugar beet originated from Rz1 resistance source were used for validation and repeatability of 6 repulsion molecular markers. Accordingly, ELISA data related to greenhouse evaluation of rhizomania resistance were used in some breeding populations. For molecular analysis, DNA was extracted from leaf samples and RAPD-PCR was performed by using the primers related to the markers of interest. The RAPD-PCR products were separated by gel electrophoresis, After electrophoresis, was stained with ethidium bromide and was observed using gel documentation device and finally was scored for the presence or absence of marker bands. In next step, conformation of the markers with ELISA data in single plants were measured in breeding populations and the precent presence of the markers in commercial varieties was determined. Comparison between ELISA and molecular analysis results showed that repulsion markers (the markers linked to the susceptibility allele) PN3 and PN7-2 had acceptable agreement with ELISA (92% and 98% respectively), susceptible varieties (87% and 90% respectively), and resistant varieties (75% and 97% respectively). Also, the results of the gene dose effect showed that the average OD value of ELISA of the dominant homozygote plants (Rz1Rz1) was significantly lower than the heterozygote plant (Rz1rz1) in the repulsion markers.

Breeding desired cultivar in rapeseed programs is the main goal of plant breeders. Modern plant breeding has been formed on the basis of variation induction, selection, evaluation and multiplication of desired genotypes. To reach these goals, mutation breeding has played an important role to neonate variation. In this study seeds of PF and Zarfam cultivars were treated with five dosages of gamma rays (500, 700, 900, 1100 and 1300 Gry). Studied traits were: plant height, number of lateral branches, number of pods per plant, length of pods and weight of 1000-seed in M2 generation. For detection of loci controlling oleic acid, SCAR and RAPD markers were used. Results showed that in PF cultivar, in all the traits except number of pods on main stem, significant deduction observed in compare with the control. In Zarfam cultivar, effect of gamma rays was significant only for the 1000-seed weight. In this study the most of relative variation coefficient between different traits belong to the number of pods on lateral branches. In this study, various lines with improved traits (lower height, more number of pods, and length of pods and 1000-seed weight) in compare with the control were obtained. Therefore, it is possible to choose desirable traits and introduce desirable variety in colza. Results of molecular markers showed that all lines treated with gamma rays in PF and Zarfam cultivars, had 399 bp and 830 bp bands.