مجله بیوتکنولوژی کشاورزی
سال پانزدهم شماره 3 (پیاپی 52، پاییز 1402)

Goal: 

production of antibodies against the coat protein of Apple stem grooving virus and their application in diagnostic assays and biosensor design represents a crucial strategy for effective plant virus detection. ASGV is a significant pathogen affecting pome fruit trees. The objective of this study was to express the coat protein gene of ASGV in E. coli, generate antibodies against the expressed protein, and assess their effectiveness in diagnostic assays.

In the PCR, we successfully amplified a 714 bp fragment corresponding to the complete coding region of the ASGV coat protein gene. The amplified fragment was then cloned into the pTG19 vector. Subsequently, the desired fragment was subcloned into the pET28a (+) expression vector using BamHI and EcoRI restriction enzymes. The resulting construct was then introduced into E. coli BL21(DE3) cells for gene expression. To determine the optimal conditions for protein expression, the transformed cells were induced with one mM IPTG for various durations (3, 4, 6, and 16 hours). The expression of the protein was confirmed through SDS-PAGE electrophoresis and western blot analysis. Following the purification of the expressed protein, it was utilized as an antigen for immunizing rabbits. Immunoglobulins (IgGs) were subsequently purified from the rabbit serum, and some of them were employed for conjugate production. The efficacy of the conjugates was evaluated in serological assays.

Sequencing analysis of the amplified fragments conclusively verified their correspondence to the ASGV coat protein gene. Moreover, PCR and enzymatic digestion of the resulting clone provided further evidence of the successful construction of pET28-ASGV-CP. Comprehensive sequence analysis of the constructed plasmid in both directions confirmed the accurate insertion of the coat protein gene into the expression vector, while also confirming the absence of any nucleotide mutations. Following optimization, the expression of the ASGV coat protein was successfully achieved, resulting in an approximate size of 27 kDa. This confirmation was attained through SDS-PAGE electrophoresis and subsequent western blotting, conducted four hours after induction. The direct, indirect, and dot-blot assays were performed to assess the efficiency of the conjugate. The results indicated that the optimal concentration of the conjugate was approximately 1:1000.

The generated and conjugated antibodies exhibit suitable titers relative to the antigen concentration and demonstrate specificity and effectiveness in the detection and identification of Apple stem grooving virus (ASGV). These antibodies can be utilized for various serological diagnostic kits, including ELISA, offering valuable applications in virus detection and identification.

The importance of wool has led to extensive research on its structure and genetic since decades ago. Identifying genes affecting economic traits is one of the most important goals of breeding in sheep. The genetic and functional potential of genes can be used to obtain animal products with the best quality and quantity. For the analysis of large data, sequencing software is cost-effective, which has greatly helped to understand the mechanisms and genetic background of various phenotypic traits in sheep. Identifying different characteristics of candidate genes and types of genotypes related to important phenotypic traits is essential in animal breeding. Therefore, the aim of the present study is to identify the genes affecting the production of wool fibers in sheep based on the functional analysis of those genes.

In order to identify genes affecting wool fibers in sheep, the data used in this research were downloaded from the GEO database with access number GSE85844. In the current study, the criterion for selecting genes is the expression difference in the range 0.3 < LogFC <-0.3 and P-value at the 5% level. After identifying and specifying the genes with significant difference (increased and decreased expression), DAVID database was used to analyze the ontology of genes. In order to investigate the interaction and relationship between the genes, the STRING database was used and the Cytoscape software package was utilized to analyze the created network.

1008 genes with different and significant expression were identified (p<0.05). Genes with Log FC <-0.3, have low expression and their number was 431, and genes with Log FC > 0.3 have high expression and their number is 577. The ontology results for CHRD, PLOD1, BMP4 and ITGA5 genes showed that these genes are effective in the pathways related to hair morphogenesis and construction, hair follicle regeneration and development and density of skin.

selecting to improve the quality of wool produced in sheep by using these findings will accelerate the genetic progress of related breeding programs.

Awns increase photosynthesis, reduce bird damage, and play a distinct role in grains spreading of wild species. However, there are some challenges to its effect on grain yield under irrigated conditions. The objective of this research was evaluation the effect of awns on important agronomic traits including grains number per spike, 1000-grain weight and earliness. For this purpose, near-isogenic line in Roshan’s background was developed to assess the effect of this trait on yield and yield components.

In the present study, in a 10-year wheat breeding program (from 2010 to 2020), awny head characteristic was transferred from Mahdavi to Roshan using backcrossing. In the second generation of the fifth backcross (BC5F2), awny and awnless progenies (isogenic lines with the genetic background of Roshan) were selected. Isogenic lines and their parents (Roshan and Mahdavi) were evaluated in a randomized complete block design with five replications in the 2021-2022 cropping season under irrigated conditions.

In the present research, the awny head character was successfully transferred from Mahdavi to the Roshan cultivar. The awny Roshan was cultivated under farm conditions (300 plants m-2). The results of mean comparisons showed that, out of the 16 evaluated agronomical traits, only three traits including grains number per spike, spikelet number per spike, and plant height were affected by awns. Awny head characteristic increased grain yield by 820 kg/ha in comparison with Roshan, but it was not significant. Awny Roshan produced 26% more grains number per spike than Roshan. The significant increase of spikelet number per spike in awny line also confirmed the increasing of grains number per spike. In comparison with Roshan, awnd isogenic line had 12 cm higher plant height, where 6 cm was due to awn length.

Awns not only did not hurt the wheat yield under irrigated conditions of Kerman but also potentially can increase grain yield by increasing the number of grains per plant. Due to the reduction of bird damage, the promising line produced in the present research can be an appropriate alternative for the Roshan cultivar.

Nowadays, environmental pollution and its consequences have become one of the most serious human concerns, and management of pollution caused by the entry of hazardous substances such as radionuclides, pesticides, and heavy metals into the environment is of particular importance. Advances in technology and nuclear knowledge have led to increasing of release and accumulation of nuclear waste and radionuclides in the environment. Mining, production and processing of nuclear fuels and military operations are the most important causes of nuclear waste production. Because of the possibility of transferring radionuclides to the food chain, soil contamination with these pollutants creates many hazards to human health. There are various physical and chemical methods to eliminate nuclear waste, but most of them are expensive and complex. Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up the polluted environment. This process is very simple, practical, economical and environmentally friendly. In this research, wheat and sunflower plants were used to remove uranium from soils of Saghand and Bandar Abbas mine's districts. Also, the effect of different concentrations of citric acid on the plants accessibility to this element was investigated.

PH meter and X-ray fluorescence spectroscopy were used to determine the pH and constituents of the soil. Also, liquid scintillation analysis was applied to determine the concentration and amount of uranium absorption.

In general, sunflower had better efficiency in absorption of uranium from soil of Saghand. In the case of uranium absorption from soil of Bandar Abbas, Wheat had better efficiency in the absence and low concentrations of citric acid, but with increasing acid concentration the accessibility of sunflower to the uranium in the soil increased.

In comparison to wheat sunflower had a better performance in uranium uptake from Saghand soil before and after acid addition. In the case of uranium uptake from Bandar Abbas soil, wheat had better performance in the absence of citric acid and in its low concentrations, while with increasing acid concentration, the uranium uptake by sunflower increased.

Due to the fact that the use of nanomaterial technology has expanded in recent years in tissue culture studies, the present study is based on the use of graphene nanomaterials and has been studied its derivatives such as graphene oxide and graphene oxide with putrescine in different levels of Ammonium nitrate was studied for increase microtuberization efficiency . This study was performed with aim of to induce suitable environmental conditions for microtuberization and stimulate anatomical and biochemical changes for in vitro conditions on potato microtuberization of Agria cultivar.The general purpose of using these compounds is to increase the osmotic potential, as well as the possibility of increasing the amount of starch grains in cells by using these nanomaterials.Nitrogen content of control medium included control, 50 and 25 percent of nitrogen of MS medium. Graphene treatments were used as control (without graphene oxide), 25 and 50 mg / l graphene oxide (alone) and 25 and 50 mg / l graphene oxide with putrescine. In this experiment, the number of microtuber in the first, second and final month microtuber, as well as the number of microtuber sproute, number of eyes, average microtuber weight, diameter of microtubers and microtubers yield were evaluated.The results showed that the most positive response to microtuberization was obtained in treatments with 25 percent nitrogen and graphene oxide with putrecsine treatments. It was also observed that the reduction of 25 percent of the culture medium nitrogen and the addition of graphene oxide with putrescine increased the final microtuberization, while the microtuberization in the control treatment (without nitrogen reduction and without graphene oxide) showed the lowest percentage. On the other hand, the results showed that 25 percent nitrogen and 50 mg / l graphene oxide with putrescine had the highest average microtuber weight (39 mg) compared to the lowest average microtuber weight (graphene oxide with putrescine without nitrogen reduction treatment) that Showed 240 percent increase in microtuber weight. In general, the use of graphene oxide with putrescine and 25 percent nitrogen could have positive effects on the microtuberization.The general results showed that reducing the amount of nitrogen in the culture medium increases the amount of microtuberization and also its effective the use of graphene and graphene oxide with putrescine in microtuberization. The results of this experiment showed that the culture medium containing 25% nitrogen and graphene oxide with putrescine were the most suitable treatments for this experiment.

Nowadays, due to the intrinsic ability of viruses in transferring genes and their incorporation into the host genome, they are used as a powerful tool for silencing and overexpression of different genes in plants. Virus-induced gene silencing (VIGS) is widely used in plant genetics for knocking genes down thanks to its ease of use and the short time required to generate the associated phenotype. Apple latent spherical virus (ALSV)-based vectors can be used for effective and stable VIGS in a broad range of plant families such as Brassicaceae, Rosaceae, Solanaceae, Fabaceae, Cucurbitaceae, Scrophulariaceae and so forth. However, to the best of our knowledge, there is no report on the replicability and applicability of this viral vector in wild strawberry and fenugreek. In this research, we aimed to optimize and evaluate the propagation of an ALSV-based VIGS vector in these two horticultural plants.

The seeds from the accession Hawaii-4 (H4) (PI551572) of the woodland (wild) strawberry, Fragaria vesca L. ssp. vesca f. alba (Ehrh.) Staudt, and Trigonella foenum-graceum (fenugreek) were planted and thereafter, the grown plants were used for inoculation. The Chenopodium quinoa was used as a propagation mediator plant. To do this, viral plasmids pEALSR1 and pEALSR2 were inoculated into C. quinoa plants by two methods, carborundum-mediated and injection-by-syringe.

The C. quinoa plants showed virus-induced chlorosis and necrosis symptoms 3-5 week after inoculation. Subsequently, the extract of infected plant tissues was inoculated onto the leaves of wild strawberry and fenugreek plants. Total RNA were extracted from all inoculated leaves and used for RT-PCR. Results indicated that a 211 bp fragment of pEALSR2 plasmid was amplified using RNA of all inoculated plants.

It was concluded that this ALSV-based vector was introduced and propagated in the target plants and can be used successfully as a VIGS vector in these plants for gene silencing and overexpression purposes.

The production of siderophore and cellulase by Trichoderma species is one of the effective indexs in plant growth, effective control and management of pathogens as well as application in industry. Therefore, primary screening of best isolates is very important based on the defined indicators.

In this study, the optimal conditions for the qualitative and quantitative production of siderophore and cellulase were investigated using test plate method for the initial screening of 27 Trichoderma strains. For measuring cellulase enzymes (Endoglucanase, exoglucanase and beta glucosidase), the reactive dyes phenol red, congo red (0.5, 0.05 and 0.015%) were used at pH levels of 4, 5, 7 and 9 with carbon sources including Avicel, CMC and cellobiose. Quantitative measurement of cellulase was investigated using the dinitrosalicylic acid method. Screening of Trichoderma strains for siderophore production was studied by CAS agar method as mycelial culture and crude extract in a well method.

The results of this research showed phenol red 0.015% under pH5 is the best reagent for detection of cellulase, Because of there is no inhibition on mycelial growth and the purple zone diameter is clear. In quantitative cellulase assay, the highest enzyme specific activity is related to T. harzianum CT-763 with 3 U/mg. T. atroviride CT-482, CT-473 and CT-865 were known as active strains in siderophore production, which were able to produce two types of siderophore, hydroximate and catechol. The results of siderophore production in liquid medium using the well method showed that T. afroharzianum CT-891 has the highest siderophore production by creating a halo zone of 1.2 cm, while T. harzianum CT566 produced the lowest amount of siderophore without creating halo.

Considering the application efficiency using of siderophore and cellulase in sustainable agriculture and importance of the role of Trichoderma species in production these metabolites, the well method for siderophore and dinitrosalicylic acid method for cellulase detection suggested. In this study T. atroviride and T. harzianum species had the highest production in siderophore and cellulase, respectively

Under the influence of various abiotic stresses, the growth, development and geographic distribution of plants change. In order to survive adverse environmental conditions and to sustain life, plants have evolved various combat and adaptive strategies to enviromntal stresses, which in the context of these defense mechanisms, is referred to metabolites accumulation such as common aliphatic polyamines (PAs) including putrescine, spermidine, and spermine.ResultsOver the last two decades, genetic, transcriptomic, proteomic, metabolomic, and phenomic modern approaches have unraveled many significant functions of different PAs in the regulation of plant abiotic stress tolerance. Studies have demonstrated that because of their polycationic nature at physiological pH, and strong binding ability to negatively charged molecules in cellular components such as nucleic acids, proteins, and phospholipids, PAs enable to largely modulate the homeostasis of reactive oxygen species (ROS) and also due to regulating and stabilizating antioxidant defense systems or suppressing ROS production improve stress tolerance in plants. Environmental stresses-induced oxidative stresses can be managed by both PAs biosynthesis and their degradation, leading protection of cell metabolism. This is ascribed to generating other metabolited and also signal molecules which participate in defense systems and energy production in Krebs cycle. ConclusionsImportant role of polyamines in stress tolerance by several lines of evidences has shown that transcript levels of polyamines-biosynthetic genes as well as the activity of related enzymes are induced by stresses. Increasing the polyamines level or expression of their biosynthetic genes through spraying with polyamines leads to an increase in stress tolerance. The reduction of polyamines has been associated with the reduction of tolerance to stress. Considering the variety of bioactivities of polyamines and their biosynthesis and degradating pathways in crop plants, this metabolic pathway in plants, identification of molecular networks and selection of effective genes can be used as candidates in breeding programs and production of stress-tolerant commercial cultivars.

Various type of agricultural waste is produced annually in the world, which have not found special application in many parts of the world. Using microorganisms with high hydrolysis activity to convert waste into compost is one of the alternative methods of incineration. In the present study, after screening the enzymatic activity of Thermoascus aurantiacus, Trichoderma sp, Bacillus licheniformis, Nocardiopsis alba and B. subtilis bacteria along with the optimization of other additives, the possibility of compost production from rice straw was investigated.

One fungal and three bacterial strains were isolated from another compost and their hydrolysis power were evaluated on specific media. Compost production was performed by optimizing the additives along with the superior microorganisms including M1 (Bacillus licheniformis, Nocardiopsis alba, B. Subtilis and Thermoascus aurantiacus) and M2 (Bacillus licheniformis, Nocardiopsis alba, B. subtilis and Trichoderma sp.) in enzymatic activity in the form of 6 treatments with 3 replications for 8 weeks. Physicochemical properties of temperature, pH, EC, C/N ratio, amount of heavy metals and nutrients, toxicity and impact on wheat growth during eight weeks were investigated.

Studies showed that fungal strain T. aurantiacus and three bacterial strains Bacillus licheniformis, Nocardiopsis alba and B. subtilis has the highest enzymatic activity in the breakdown of xylan, cellulose, lignin and starch. Treatment G (containing poultry manure and T. aurantiacus) caused a significant increase in temperature of rice straw mass (63 °C) and also a significant decrease in C/N ratio (73.48%) (at the pilot level). Germination index test showed that G treatment did not have phytotoxicity and had the most positive effect on wheat growth indexes compared to the control.

According to the comparison of treatments with and without microorganisms, it was found that the hydrolysis power of T. aurantiacus has the most positive effect on physicochemical properties, especially reducing the C/N ratio and can be used as a commercial additive in compost production.

In order to identify the genes involved in the resistance of date palms to spider mite, sampling was taken from three relatively resistant and three susceptible date palm cultivars at the end of July in the Kimmeri stage, simultaneously with mite activity. Then the activity of some genes was investigated with the aim of determine the molecular mechanism of date palm resistance to the spider mite.

After RNA extraction and cDNA synthesis, the expression of 7 genes, including bZIP, MPK6, Peroxidase72, MurG, Lipoxigenase, ACC synthase and ACC oxidase genes, were investigated by qRT-PCR in susceptible and semi-resistant cultivars. In order to design the primers, the selected genes CDS were aligning with the date palm genome and finding related genes by Clustal W then primers were designed using Primer3 databases. After the end of the experiment, the amount of gene transcripts were determined and compared.

The MurG gene showed higher expression in relatively resistant cultivars: Zahedi, Hallawi and Estamaran than susceptible cultivars: Lilwi, Khadrawi and Barhee (Zahidi maximum and Lilwi minimum). The expression of the Peroxidase72 gene in relatively resistant cultivars including Zahedi (100%) and the lowest expression related to susceptible cultivar Lilwi (76.81%). The bZIP gene was found in relatively resistant cultivars including Zahedi (100%) and the lowest expression in the susceptible cultivar Lilwi (78.19%). The Lipoxigenase gene was found in relatively resistant cultivars including Zahedi (100%) and the lowest expression in the susceptible cultivar Lilwi (73.56%). The expression of the ACC synthase gene in relatively resistant cultivars including Zahedi (100%) and the lowest expression was in the susceptible cultivar Lilwi (81.56%). The ACC oxidase gene was in relatively resistant cultivars including Hallawi (100%) and the lowest expression was in the susceptible Lilwi cultivar (85.37%). MPK6 gene expression was observed in all three susceptible cultivars, but no expression was observed for this gene in all three relatively resistant cultivars.

The expression of some genes in susceptible and resistant cultivars followed a regular pattern and the expression of other genes had an irregular pattern. As a result, it can be concluded that the role of MurG and bZIP gene product is up regulating the resistance of date palm to mite, but the role of MAPK6 gene product is down regulating the resistance of date palm to mite.

This study was conducted to investigate the effects of zinc hydroxide and zinc glycine and their mixtures on performance, blood and immune parameters, liver enzymes and expression of interleukin-6 and interferon gamma genes in broiler chickens.

Birds fed on a Corn-Soybean. The study was conducted in a completely randomized design with a 3×3 factorial arrangement with 9 treatments and 4 replications, each replication containing 15 birds. (540 Ross 308 broiler chickens). The experimental diets included the control diet (without zinc hydroxide and zinc glycine) and the levels of 50 and 100 mg / kg zinc hydroxide and zinc glycine.

The results showed that the use of mixture of zinc hydroxide and zinc glycine increased feed intake and weight at the end of broiler chickens breeding (P<0.05). Among the experimental groups, 100 zinc hydroxide (mg/kg of feed) had the blood and immune parameters (P<0.05). The use of zinc hydroxide and zinc glycine in the diet of broiler chickens has significant effect on liver enzyme (P<0.05). The different levels of zinc hydroxide and zinc glycine decreased the expression of interleukin-6 and increased gamma interferon liver genes.ConclusionsIn general, it can be stated that the mixture containing 100 zinc hydroxide (mg/kg of feed) has the most effect on performance improvement, blood and immune parameters and100 zinc hydroxide and zinc glycine (mg/kg of feed) expression of liver genes in broiler chickens.The results showed that the use of mixture of zinc hydroxide and zinc glycine increased feed intake and weight at the end of broiler chickens breeding (P<0.05). Among the experimental groups, 100 zinc hydroxide (mg/kg of feed) had the blood and immune parameters (P<0.05). The use of zinc hydroxide and zinc glycine in the diet of broiler chickens has significant effect on liver enzyme (P<0.05). The different levels of zinc hydroxide and zinc glycine decreased the expression of interleukin-6 and increased gamma interferon liver genes.

In general, it can be stated that the mixture containing 100 zinc hydroxide (mg/kg of feed) has the most effect on performance improvement, blood and immune parameters and100 zinc hydroxide and zinc glycine (mg/kg of feed) expression of liver genes in broiler chickens.

Environmental stresses such as drought, high temperature, salinity and high CO2 are a serious threat to sustainable agriculture. Drought stress is one of the most important abiotic stresses in rice, which causes a decrease in crop yield. Several researches have been carried out separately to clarify the molecular mechanism of plant response to drought stress. Therefore, meta-analysis can lead to a better understanding of drought stress tolerance mechanisms by integrating the results of several related studies.

In this regard, four series of good quality microarray data of rice under drought stress and normal condition were selected and then analyzed by R software limma packages. For meta-analysis were used of meta-RNAseq package and Fisher's method to combine p-values obtained from individual data analysis. Up and down regulated meta-analysis genes under drought stress were identified. Then, Gene ontology, hub genes and Co-expression network analysis were performed. The results were evaluated using real-time quantitative PCR test in Hashemi rice as sensitive variety and native rice as tolerant variety to water deficit stress in vitro with PEG treatment.

The results of present study, 578 up-regulated genes and 660 down-regulated genes were obtained. Gene ontology (GO) analysis showed drought response mechanisms and drawing the protein-protein interaction network revealed that the down regulated hub genes under drought stress is mainly related to photosynthesis process and up regulated hub genes under drought stress mainly related to stress tolerance including HSP, LEAs, PP2Cs genes. Finally, the data obtained from the present meta-analysis were confirmed by real-time quantitative PCR on peroxidase 47, OsDSSR1, homeobox-leucine zipper protein and an unknown gene. These findings significantly improve our understanding of drought stress pathway. Identification of hub genes in this study can be effective to obtain an overview of hub genes that play an important role in response to drought stress in rice.

Identifying downstream of hub genes can help in the production of drought-tolerant rice through classical breeding methods by pyramiding genes or genome manipulation and increase tolerance to drought stress.The result will lead to sustainable agriculture.

The locations of ROHs which are under positive selection, or laboring favorable allele in population, tend to be fixed in the genome and formation of ROH Island during long times. Also, selection not only increases the frequency of new-useful mutations but also remains some signals throughout the genome. Since these regions are often control economically important traits, identifying and tracking these regions is the most important subject in the animal genetics.

In order to identify the signatures of selection and ROH Islands, 81 native Zandi sheep including prolific ewes (42 animal) and others with only singleton records (39 animal) were genotyped using the medium-density Illumina Ovine SNP50 array. Theta unbiased statistical method in R software was used to identify selection signatures. Candidate genes were identified by SNPs located at 0.1% upper range of Theta using BioMart software in ensemble 109. Also the detectRUNS package of R was useful to find the proportions of the homozygous genome and one percent of SNP with the highest frequency in ROH were considered as ROH Islands.

Based on the results of obtained Theta values genomic regions on chromosomes 1(3 regions), 2 (2 regions), 5, 6 (2 regions), 8 (2 region), 10 and 25 were identified. A total of 17 ROH Islands with length: 270.46 Kb to 8.25 Mb related to studied trait were identified, which covering less than 1% of the sheep genome. The ROH Islands was not distributed across the genome uniform. The highest number ROH Island was observed on chromosome 1, while the lowest was on chromosome 24. Candidate genes PER2, KCNH7, CLCN3, UTG8 and EPHA5 obtained these regions. Further investigation using bioinformatics tools showed these genomic regions overlapped with the genes associated with development of ovarian granulosa cells, ovulation rate, lipid transport in Sertoli cells and early growth fetus.

The results of this study revealed that, the selection processes in different sheep breeds for economic traits during several years, has led to the formation of many ROH islands in sheep genome, therefore scanning these regions at the genome level can be an alternative strategy to identify genes and associated loci with economic traits. However, it will be necessary to carry out more association and functional studies to demonstrate the implication of these genes.

Flowering time in bread wheat is controlled by three groups of genes including photoperiod (Ppd), vernalization (Vrn) and earliness per se (Eps). The objective of the present study was to assess the effect of photoperiod and vernalization genes on phenology of bread wheat using near-isogenic lines (NILs) in three genetic backgrounds.

Genomic DNA was extracted from parents, the earliest and the latest heading genotypes of each BC5F2 population obtained from backcrossing three Iranian cultivars including Roshan, Mahdavi and Kalheydari (recurrent parents) with Australian cultivar, Excalibur (donor parent). PCR was performed using specific primers for Ppd and Vrn genes.

Excalibur and Mahdavi had Ppd-D1a allele whereas Kalheydari and Roshan were carrying Ppd-D1b allele. As it was expected, early and late heading progeny of Mahdavi were similar to parents. Late heading progeny of Roshan was homozygote and similar to recurrent parent whereas early heading progeny was heterozygote. Early and late heading progeny of Kalheydari were heterozygote. The reason for this could be the presence of modifier genes that are influenced by genetic background. Excalibur, Kalheydari and Mahdavi were possessed Vrn-B1a and vrn-D1 alleles, while Roshan carried vrn-B1 and Vrn-D1a alleles in Vrn-B1 and Vrn-D1 loci, respectively. Since Excalibur, Kolhaydari and Mahdavi did not show genetic diversity, as it was expected, early and late heading progeny were similar to their parents. In Roshan background, since vrn-B1 and Vrn-D1a improve earliness, early and late heading progeny were similar to recurrent parent.

The Ppd-D1a allele discriminated early and late heading progeny of Roshan genetic background. This result showed the importance and role of this gene on earliness. Early and late heading progeny of Roshan were similar to Vrn-B1 and Vrn-D1 loci. The reason is phenotypic selection for earliness in backcrossing program, where genes controlling late maturity have not selected during phenotypic selection.