جمشید سلطانی ایدلیکی

Sugar beet is one of the root knot nematode (Meloidogyne spp.) hosts and destructive virus (Beet necrotic yellow vein virus, BNYVV) which is the cause of rhizomania disease. The use of resistant cultivars is the simplest and most efficient method of managing plant diseases. Based on this, to develop a cultivar resistant to rhizomania and root knot nematode in sugar beet, two populations carrying resistance genes to the above-mentioned diseases were identified and selected. From the target population, 10 half-sib families were developed and crossed with single cross monogerm 7112*SB36 and 10 monogerm hybrids were developed. Evaluation of hybrids in terms of quantitative and qualitative traits led to the selection of four superior hybrids including SBSI043, SBSI042, SBSI041 and SBSI044. Results of combined analysis of these hybrids with a domestic resistant control to rhizomania (Arya) and two foreign resistant controls (Castile and Rosier) and a susceptible cultivar for two years in a field infected to rhizomania in four regions (Mashhad, Shiraz, Hamadan and Qazvin) showed the complete superiority of all four hybrids compared with domestic resistant control. This hybrid was recognized as the best domestic hybrid in the test to determine the agricultural capacity of new domestic cultivars in seven infected and non-infected regions of the country, with an average sugar yield of 8.79 tons per hectare after two foreign controls. The new hybrid SBSI043 is the first cultivar with double-resistant (rhizomania and root knot nematode) named "Asia" and was introduced to growers for spring cultivation in different regions of my country, especially the regions infected to both diseases and exports to Azerbaijan, Syria and Egypt countries.

Cystic nematode is one of the limiting factors of sugar beet growth. Considering the importance and extent of this nematode in Iran and in order to prevent its damage, it is recommended to use resistant cultivars. The prerequisite for the development of resistant cultivars is the presence of resistant genotypes. Therefore, this study was aimed to evaluate the quantitative and qualitative yield of new sugar beet hybrids and determining their agronomic value in the field with natural infection under sugar beet cyst nematode in Razavi Khorasan province.

In order to determine the agronomic value of advanced sugar beet hybrids, 15 new domestic hybrids along with two resistant (Aria) and sensitive (Sharif) control cultivars were evaluated during the years 2020 and 2021 in the field infected with cystic nematode in Torogh Agricultural Research Station (Mashhad) in the form of randomized complete block design with four repetitions. The investigation of resistance to sugar beet cyst nematode of 17 genotypes was also carried out under greenhouse conditions using a completely randomized design with 10 replications. Muller's method was used to evaluate cultivars under greenhouse conditions. After performing the homogeneity of variances test through Bartlett's test, composite analysis of two years' data was done. By using correlation coefficients between measured parameters, their relationships were compared to each other. In order to group the experimental materials, Ward's cluster analysis was used. LSD test was used at the probability level of five percent to compare the mean of the traits.

The combined analysis of variance showed a significant difference between the hybrids in terms of all traits. Mean comparison showed that hybrid SBSI 126 had the highest root yield (57.91 tonha-1). In addition, this hybrid had higher values of sugar content, sugar yield and white sugar yield than the resistant control cultivar (Aria) as well as the average of all genotypes. The SBSI 138 hybrid had the lowest values of root yield, sugar yield, white sugar yield, sugar content and white sugar content, and it was the most sensitive genotype to cyst nematode among the genotypes after the sensitive control variety (Sharif). The results of cluster analysis in the field experiment showed that hybrids SBSI 126, SBSI 129 and SBSI 128 had high yield potential and were placed in one cluster.Correlation coefficients of studied traits showed that the highest positive and significant correlation (0.97) was found between root yield and sugar yield and the highest negative and significant correlation (-0.93) was also obtained between extraction coefficient of sugar and sugar beet molasses. There was a positive and significant correlation at the level of 1%between white sugar yield and root yield (0.85), sugar content (0.40), sugar yield (0.95), potassium (0.57), nitrogen (0.51) and molasses sugar percentage (0.25). While a negative and significant correlation was observed between white sugar yield and alkalinity coefficient (-0.52) at the level of 1%. In this research, there was a significant difference at the level of 1% between the evaluated genotypes in greenhouse conditions in terms of female index of the cyst nematode (FI). The results of cultivar grouping according to Schmidt and Shannon showed that the SBSI 126 genotype with the lowest index (11.66%) has the highest resistance among genotypes.

In general, the results showed that the SBSI 126 hybrid can be recommended as a cyst nematode-resistant hybrid for growing in infected fields due to its resistance and high white sugar yield.

Plant breeding is based on genetic diversity. Genetic diversity originates from natural evolution and is the most important component in the stability of biological systems and ensures long-term adaptation and population survival . Conventional agriculture has caused a drastic reduction in the diversity of crop plants. Among the 30,000 identified edible plant species, only 30 species are the main sources of nutrition for the world's people. Considering that the existence of genetic diversity is necessary for success in plant breeding, therefore, the selection of superior genotypes from among the modified populations depends on the existence of genetic diversity. The purpose of this research is to evaluate the genetic diversity of sugar beet half-sib families in the conditions of natural infection with rhizomania and cyst nematode and to determine the relationships of different traits using multivariate statistical methods.

This experiment was studied the half-sib families of sugar beet (90 lines) in a field naturally infected with cyst nematode and rhizomania at Torogh Agricultural Research Station (Mashhad) in 2020 using Augmented design with four controls, Aria, Fernando, Pauletta and Sharif.

The results of analysis of variance showed that there was a significant genetic diversity among the half-sib families studied in terms of root yield, sugar yield and white sugar yield. The highest amount of heritability among the evaluated traits was related to white sugar yield with 86.87% heritability, which indicates that this trait is less influenced by environmental factors. In this research, white sugar yield had a positive and significant correlation with all traits except molasses sugar percentage at the probability level of 1%. Stepwise regression showed that the two attributes of sugar yield and extraction coefficient of sugar cause more than 99% of changes in white sugar yield. Path analysis results showed that sugar yield had the most direct and positive effect on white sugar yield. Based on cluster analysis, the experimental genotypes were classified into three distinct groups; So that the first group included half-sib families that had high root yield and sugar.

Due to the existence of considerable diversity between the traits and experimental half-sib families, half-sibs with desirable traits can be selected based on breeding goals and used in future breeding programs in order to prepare cultivars resistant to cyst nematode and rhizomania diseases.

To prepare and evaluate test cross hybrids resistant to rhizomania and cyst nematode based on new single crosses, 48 test cross hybrids produced were evaluated in 2021 in the augmentation design along with Iranian and commercial hybrid varieties in six regions )Karaj, Mashhad, Shiraz, Kermanshah, Miandoab, and Hamadan(. Genotypes mean comparison showed that BTS2015N had the highest root yield in Karaj, Mashhad, Shiraz, Kermanshah, and Hamadan and an average of six locations with an average of 133.97, 114.45, 77.14, 102.80, 97.08, and 104.91 t/ha, respectively. The Wawilow cultivar also had the highest sugar content in Karaj, Mashhad, Shiraz, and Kermanshah and an average of six locations with an average of 17.61, 18.31, 24.06, 19.57, and 18.62 percent, respectively. In addition, in a total of six locations, there was no significant difference among hybrids 39, 40, 31, and 35 in terms of root yield and hybrids 24 and 47 in terms of sugar content with the external control cultivar BTS2015N. In this study, new hybrids 40, 38, 23, Nika, and Bifort cultivars have the lowest ASV values with 0.062, 0.117, 0.154, 0.245, and 0.256, respectively, were considered stable genotypes in terms of root yield. Also, based on the results of the GGE biplot method, the new hybrids 13, 24, 32, 23 had the highest general stability. In this study, the BTS2015N cultivar for the environments of Karaj, Kermanshah, Shiraz, and Hamadan and the Annamira KWS cultivar for the Miandoab environment showed high specific adaptability.

Beet necrotic yellow vein virus (BNYVV) and Beet black scorch virus (BBSV) have been observed in infected sugar beet roots from Iranian fields. This study aimed to detect the two viruses simultaneously to save time and energy during the infection detection process.

Three methods were utilized in this study. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect two viruses following total RNA extraction from the farm sample. In the first method (the standard method), the mentioned viruses were identified by amplifying 545 bp fragments from the TGB region of the RNA2 genome of the BNYVV virus and 305 bp fragments from the 3'UTR region of the BBSV virus using specific primers. Viruses on an infected root were identified using RT-PCR with primers specific to each virus and performed independently. In the second and third methods, we employed simplex and duplex RT-PCR gradient methods to simultaneously identify two viruses at annealing temperatures of 52, 54, and 56 °C. To this end, virus-specific primers (designed from a part of the gene encoding the coat protein) were used separately but simultaneously with a common PCR program in a thermocycler. These specific primers amplified 391 and 453 bp fragments of the BNYVV and BBSV coat proteins, respectively.

The study's findings show that by performing simplex and duplexRT-PCR simultaneously and optimizing the annealing temperature of primers from the gene encoding the protein coat, target fragments of 453 and 391 bp from BBSV and BNYVV, respectively, are amplified. This study found that an annealing temperature of 56 °C is the optimal temperature for duplex RT-PCR to separate the two viruses. Consequently, simultaneous identification of the BNYVV and BBSV was achieved through this method.

The present study demonstrates that simplex and duplexRT-PCR are suitable for simultaneous detection and are cost-effective in terms of saving time and energy. They can also be used to prepare distribution maps in sugar beet cultivation areas and to evaluate and identify resistant sugar beet lines in breeding programs under greenhouse conditions.

Correlation between yield and qualitative traits of sugar beet cultivars with rhizomania disease indices under field infection conditionsAbstractBackground and ObjectivesRhizomania viral disease is one of the limiting factors of sugar beet cultivation and significantly reduces its yield. The most important way to deal with this disease is to use resistant cultivars. Materials and MethodsIn order to evaluate the correlation between yield and qualitative traits of sugar beet cultivars with rhizomania disease indices, an experiment was conducted in a randomized complete block design with 12 different sugar beet cultivars in four replications in field with natural infection with rhizomania in 2018. The traits studied in this study included root yield, sugar content, sugar yield, white sugar content, white sugar yield, sodium, potassium, trace nitrogen, alkalinity, sugar extraction coefficient, leaf growth score, root growth score, disease severity and ELISA test index (OD). Analysis of variance was performed using SAS v.9.1 statistical software. Mean comparisons of traits were performed using LSD test at the probability level of 5 and 1%. ResultsAnalysis of variance showed significant differences among genotypes for all studied traits except for sodium and potassium. Cluster analysis of yield, crop quality as well as rhizomania severity of infection divided the sugar beet cultivars into three groups. Correlation between traits in a rhizomania infected field and different levels of resistance to rhizomania was different. DiscussionIn all cultivars with different levels of resistance, there was a significant correlation between pure sugar yield with leaf growth score (r = 0.95 **), root growth score (r = 0.94 **), disease severity (r = 0.92 **) and ELISA index (r = -0.68 **) was observed. Therefore, these traits are suitable indicators for evaluation of cultivars for suseptibility or resistance to rhizomania disease. In addition, correlation between leaf growth index and ELISA (r = 0.87 **), root growth score (r = -0.85 **) and disease severity (r = -0.60 *) was significant.Correlation between yield and qualitative traits of sugar beet cultivars with rhizomania disease indices under field infection conditionsBackground and ObjectivesRhizomania viral disease is one of the limiting factors of sugar beet cultivation and significantly reduces its yield. The most important way to deal with this disease is to use resistant cultivars. Materials and MethodsIn order to evaluate the correlation between yield and qualitative traits of sugar beet cultivars with rhizomania disease indices, an experiment was conducted in a randomized complete block design with 12 different sugar beet cultivars in four replications in field with natural infection with rhizomania in 2018. The traits studied in this study included root yield, sugar content, sugar yield, white sugar content, white sugar yield, sodium, potassium, trace nitrogen, alkalinity, sugar extraction coefficient, leaf growth score, root growth score, disease severity and ELISA test index (OD). Analysis of variance was performed using SAS v.9.1 statistical software. Mean comparisons of traits were performed using LSD test at the probability level of 5 and 1%.

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.

Beet black scorch virus is one of the soil-borne sugar beet viruses in Iran. In this research work, we collected 80 samples of sugar beet farms in Razavi and Northern Khorasan Provinces. After extraction of their total RNA, the 3'UTR region of the virus genome was amplified to 315 nucleotides using reverse transcription polymerase chain reaction using specific primers. The 3'UTR of six different isolates was sequenced following cloning and then submitted to NCBI. Phylogenetic analysis based on nucleotide sequences of the 3'UTR region showed that the entire world isolates could be classified into two main groups II and I and each one was divided into two subgroups. Isolates of this study were grouped with 23 isolates from Iran in subgroup IA and Four isolates from Khorasan province were placed in the IB subgroup. Four Iranian BBSV isolates from the West were grouped in the subgroup GIIA. All Chinese isolates and the European isolates together with the USA isolate clustered in subgroup GIIB. The results of nucleotide comparison of six isolates showed that although no mutation occurred at position 3477 (uridine instead of guanine), However, in position 3398, adenine replaced guanine (similar to 60% of Iranian isolates) and in position 3393, uridine was substituted for cytosine only in Fariman isolates (MW274750). The results of comparing the average nucleotide identity of 3'UTR isolates in this study showed that they are identical to Iranian isolates in the range from 97.75% to 97.98%. Nevertheless, they had the least identity with Kermanshah isolates (92.52%).

One of the most important diseases of sugar beet (Beta vulgaris L.) is Rhizomania or Root madness, which is currently prevalent in all parts of the world. The damage of this disease in susceptible cultivars has been estimated at more than 50% and in some cases up to 100%. Due to the increase in the countrychr('39')s population and the need for sugar, sugar beet crop has a special place among crops. To evaluate genetic parameters, relationships between traits, and grouping of different sugar beet genotypes, 44 sugar beet hybrids in four regions (Hamedan, Kermanshah, Mashhad, and Shiraz) was evaluated in 2019. The experiment was conducted in the form of an incomplete block design (alpha latest) in 6 replications. The results showed that sugar content and root yield with 88.24 and 59.53%, respectively, had the highest and lowest values of broad-sense heritability. In this study, white sugar yield with root yield, sugar content, sugar yield, sugar extraction coefficient, and white sugar content showed a positive and significant phenotypic and genetic correlation, and with root potassium content and molasses sugar had a negative and significant correlation. Based on stepwise regression analysis root potassium, sugar content, and nitrogen content were explained 52% of the white sugar yield variation and identified as the most effective traits in justifying white sugar yield variation. Cluster analysis classified 44 hybrids and 3 controls of sugar beet cultivar into four clusters in four locations. Cluster number four included hybrids No. 20, 43, 31, 23, 25, 24, and 37 and foreign control cultivars Succara and BTS 213, and had the most suitable quantitative and qualitative characteristics. In factor analysis through principal component analysis, two factors were identified that explained 82.52% of the total variance of the data. In this study, root potassium content and sugar content were identified as the most effective traits, and hybrids located in the cluster of four identified as the most suitable hybrid for future breeding programs.

Testing plant varieties under different regions is necessary to assess their stability. In this study, 17 sugar beet genotypes were evaluated in a randomized complete block design with six replications in five regions including Karaj, Hamedan, Miandoab, Mashhad, and Shiraz. After checking the homogeneity of mean squares in five experiments by Bartlett’s test, analysis of the combined was performed for sugar yield. In this analysis, location, genotype and genotype × location interaction effects were significant. Based on regression coefficient and deviation from regression parameters, genotypes G2, G6, G9 and G13 were the most stable genotypes. Genotypes G2, G3, G5 and G6 had the highest stability based on Shukla’s stability variance and Wrick’s ecovalence. Based on superiority measure, genotypes G6 and G9 and based on coefficient of variation genotypes G2 and G5 were identified as the most stable genotypes. Using coefficient of determination, genotypes G3, G5 and G6 were selected and by Tai’s regression method, genotypes G2, G6 and G12 genotypes were selected as the most stable genotypes having sugar yield higher than average. Based on the above mentioned methods, genotype G2 was recognized as the most suitable genotype for sugar yield stability.

Soil-borne sugar beet viruses are responsible for the destructive diseases of sugar beet. They can cause significant yield losses worldwide. Four of the soil-borne sugar beet viruses consisted of Beet necrotic yellow vein virus (BNYVV), Beet soil-borne mosaic virus (BSBMV), Beet soil-borne virus (BSBV) and Beet virus Q (BVQ) are transmitted by the protis Polymyxa betae, a common root infecting parasite which ensures the long-term persistence of the viruses in the soils and one consisted of Beet black scorch virus (BBSV), is transmitting by Olpidium brassicae. So far, four out of five aforementioned viruses have been reported (except for BSBMV) in Iran. BNYVV is the causal agent of the rhizomania disease which has been reported in mixed-infections with BSBV, BVQ and/or BBSV. In previous studies, BSBV, BVQ and BBSV have been found alongside the BNYVV in some root samples. Nevertheless, up to now, no field has been spotted with black scorch symptoms of sugar beet leaves. Recently, we observed symptoms of burns on leaves and similar signs of rhizomania disease in the roots of some sugar beet cultivars in the fields of Khorasan Razavi province. The purpose of this study was to detect soil-borne viruses of sugar beet and determine some of their molecular aspects.

In this study, sugar beet with bearded roots and black scorching of leaves symptoms were collected from Mashhad, Fariman, Chenaran, Jolge-Rokh, and Jovein sugar beet fields. Total RNA was extracted from 100 mg of rootlets using RNeasy Mini Kit (Qiagen-Germany) based on the manufacturer's protocol. The presence of three viruses of BSBV, BVQ and BNYVV were analyzed by multiplex reverse transcription-polymerase chain reaction (mRT-PCR). However, For BBSV detection, simplex RT-PCR was used to detect of the 3′-UTR of the genomic RNA. For the molecular characterization of the BNYVV isolates, the BNYVV type (A or B) was determined with duplex RT-PCR (dRT-PCR), using A/B-type-specific primers pairs for the triple gene block (TGB) gene in RNA-2 and the partial p25 gene of the RNA-3 segment of the virus. RT-PCR was done using the PrimeScript™ Reverse Transcriptase kits and the PrimeSTAR GXL DNA Polymerase (Takara, Japan). The PCR products were cloned in pGEM®-T Easy Vector (Promega-USA). The recombinant plasmids were extracted using PrimPrep Plasmid DNA isolation kit (GenetBio-Korea) and then sequenced (Macrogene, South Korea). Nucleotide sequences data were analyzed using Chromas (version 1.45) and MEGA7 softwares.

The results showed that in the three samples with bearded root symptoms (Mashhad, Jovein, and Jolge-rokh), only BNYVV (A-type) was present and there were no BSBV and BVQ in the tested samples. In addition, in the two samples (Fariman and Chenaran), none of the three viruses was detected. The results showed that the two BNYVV isolates had ‘ACHG’ (Mashhad and Jolge-Rokh isolates) or ‘AHHG’ (Jovein isolate) residues in the tetrad position. So that the amino acid cysteine (C) in a68 position was converted to histidine (H). Although this A-type tetrad has been previously reported by Mehrvar et al. (2009) in Khorasan Razavi and Northern Khorasan, Semnan, Qazvin, Zanjan, Ilam, Hamedan, and West Azarbaijan provinces. In this study, BBSV was detected in all samples. In Mashhad, Jolge-rokh, and Jovein samples, BNYVV was present accompanied by BBSV. However, BBSV was detected alone from Fariman (holding black scorching of the leaves and vascular necrosis of root symptoms) and Chenaran (black scorching of the leaves) samples. These results are consistent with the results of other researchers from Spain and the United States who reported the presence of rhizomnia symptoms in the BBSV infected roots.

While most of  the farmers in Khorasan province cultivate resistant cultivars of sugar beet carrying the Rz1 gene for successive years in a field, the breakdown of the resistance and emerging of new resistance breaking (RB) variant of the virus have occurred via amino acid changes. However, more research on BNYVV pathogenicity by the use of additional sources of resistance and alternative disease control majors is needed to have a suitable conclusion. In addition, the results of this study showed that the presence of both viruses (BBSV and BNYVV) together could exacerbate the Rhizomania syndrome symptoms while single infection by BBSV could just cause vascular necrosis in the root and black scorching symptoms of the leaves. This could be very important in symptoms based diagnosing of the disease and preventing errors in evaluating the resistance of sugar beet cultivars in the field.

Beet black scorch virus (BBSV) is a soil-borne virus infecting sugar beet. In order to construct an infectious full-length cDNA clone of Mashhad isolate (IR-Mash1), Iran (GenBank Accession no. MK092329), and studying reaction of some sugar beet cultivars, sugar beet roots with beard lateral root growth were collected from Mashhad field and subjected to total RNA extraction and then cDNA synthesis. PCR reaction was performed to amplify the whole genome of the virus were cloned to pDrive Cloning Vector. DNA was extracted from the plasmid vector. It was used as templates for run-off transcription in vitro by use of a T7 RNA polymerase. Chenopodium quinoa was inoculated under greenhouse conditions. Necrotic local lesions formed on C. quinoa (5 dpi) leaves were used as inoculation material for inoculation of the leaves of different sugar beet cultivars grown in the greenhouse. BBSV was inoculated by rubbing the sugar beet seedling leaves. Iranian cultivar including Sharif (susceptible check), Aria, Shokoufa and foreign cultivar including Pauletta KWS (tolerant to Rhizomania and sugarbeet cyst nematode), Isabella KWS (Double Resistant to Rhizomania) and Dorothea (tolerant to Rhizoctonia) cultivars were inoculated under greenhouse conditions. Pinpoint Symptoms appeared on the leaves of all cultivars after twenty days. The result showed that the virus produces similar symptoms on leaves of susceptible and resistant cultivars to Rhizomania. So, using infectious clone, possible to screening sugar beet germplasms as part of pre-breeding programs under greenhouse conditions and to find sources of resistance to the virus in sugar beet and wild beets.