Disease Of Mungbean Research Articles

Antimicrobial effect of green synthesized TiO<sub>2</sub> nanoparticles against Cercospora canesces growth in mung bean

Mung bean is one of the economically important leguminous crops generally grown in arid region of Pakistan. Mung bean grows best at 30-35℃ and is a nutrient enriched crop with higher amounts of starch (50%), proteins (18-25%), fat (3%) and fiber (3-4.5%). Many biotic factors affect crop production. Yield losses due to biotic factors are up to 40-80% in mung bean. Cercospora leaf spot (CLS) is very common disease in mung bean caused by hemi-biotrophic fungal pathogen Cercospora canescens. For sustainable agrocontrol there is need to develop alternative solutions for conventional methods. Green synthesized nanoparticles offer promising solution to mitigate adverse effect of agrochemicals and fungicides. In this review green synthesized TiO2 nanoparticles used to mitigate the disease severity by seed priming with 50mgL-1 and 150mgL-1 nanoparticles (NPs) suspension solution in mung bean. The result shows that 50mgL-1 Tio2-NPs inhibit fungal growth by 87.85% in in vitro and 74.07% in in vivo experiment. Tio2-NPs application improve root, shoot, leaf surface area, chlorophyll content, stomatal conductance and boost plant immunity by enhancing expression of the Pathogenesis-related (PR-1) gene in response stress. Therefore, present study indicates that green synthesized Tio2-NPs is an effective way to enhance the growth and productivity of mung bean by inhibiting C. canescens.

First Report of Stem Blight of Mungbean (Vigna radiata) Caused by Diaporthe longicolla in the United States.

Mungbean (Vigna radiata) is primarily grown in Asia and directly consumed by humans. U.S. consumers embraced mungbean as a plant-based protein in vegan eggs and meat substitutes. New cultivars are being developed for American farmers because of the crop's tolerance to heat and drought, and its adaptability to current farming infrastructure. Mungbean's short season complements various cropping systems such as intercropping, alternative cropping, and green manure. With rotations and inclusion with soybean systems, there is a concern about the overlap of common pathogens for soybean and mungbean. During August 2022 when mungbeans reached full maturity (growth stage R6), reddish-brown and necrotic stem lesions with linear rows of black pycnidia were observed on Berken and OK2000 cultivars at fields located in Hancock County, IA and Story County, IA in the United States. Pycnidia measured 0.5-0.6mm in length. Disease incidence was approximately 10% of plants in Hancock County, IA and less than 3% of plants in Story County, IA. Pycnidia from 16 plants were excised and immersed in a 0.5% NaOCl solution for 1 min, rinsed with autoclaved distilled water, and placed onto potato dextrose agar (PDA). Eighteen isolates were hyphal tipped and grown on PDA and were stored at 25°C. Isolates were then visually identified by culture and conidia morphology (Hobbs et al. 1985, Santos et al. 2011). Colonies were cream to white, dense, and floccose. Large black stromata were formed in a concentric pattern or scattered; alpha conidia were ellipsoidal. Template DNA for PCR amplification of the internal transcribed spacer region of the nuclear ribosomal DNA operon (ITS) and the beta-tubulin gene (TUB) was extracted from 18 isolates by scraping mycelia with a sterile pipette tip and transferring it into 50 ul of PrepMan Ultra Sample Reagent (Applied Biosystems, Foster City, California, USA). Fungal primers were ITS1 and ITS4 (White et al. 1990) and Bt-2F/Bt-2R (Udayanga et al. 2014). Sequences of isolates obtained from fields in both counties were identical, providing no species diversity. GenBank accession numbers for the ITS region were PP105598 and PP105599; PP108254 and PP108255 for TUB sequences. BLAST results showed the ITS 550/550 base pairs with type specimen D. longicolla ATCC 60326 GB NR_144924 and the TUB 446/446 base pairs with type specimen D. longicolla ATCC 60325 GB KJ610883. Thus, the isolates were identified as Diaporthe longicolla (Hobbs) J.M. Santos, Vrandecic & A.J.L. Phillips based on morphology and molecular characters (Santo et al 2011; Udayanga et al. 2014). To confirm the pathogenicity of the D. longicolla isolates, twenty mungbean plants (cv. Berken and OK2000) were grown in the greenhouse at 85% RH and 16hr light for 20 days. Inoculum was prepared by placing sterile toothpicks on 1/3 PDA with a single representative isolate from each field location for 21 days (Ghimire et al. 2019). Mungbean plants were grown in a 10cm-by-10cm pot containing a greenhouse professional growing mix (Sungrow, Agawam, Massachusetts, USA) and grown for 30 days post emergence. After 12 days of growing, a 3mm segment of the infested toothpick was inserted into a stem wound below the first trifoliate and sealed with parafilm. A sterile toothpick was inserted into the control plants. After 14 days, red lesions extended downward 1 to 3 cm from the inoculation site, and white mycelial was present in the wound. At 21 days red lesions spanned 3 to 9 cm upward and downward from the inoculation site. Pycnidia were present on collapsed stem tissue, and leaves became chlorotic. Damage was limited to 2mm from the mock-inoculation site, with no discoloration in the control plants. Symptomatic tissues were plated and compared to the original isolates. Alpha conidia were ellipsoidal with the base end rounded. To our knowledge, this is the first report of Diaporthe longicolla causing disease on mungbean within the U.S. and worldwide. The presence of this disease in two locations suggests the potential for Diaporthe longicolla to be a serious disease of mungbean in the future.

First report of leaf spot caused by Colletotrichum camelliae in mung beans (Vigna radiata (L.) R. Wilczek) in South Korea.

Mung bean (Vigna radiata (L.) R. Wilczek) is a legume with high nutritional and economic value that is cultivated widely across Asia (Kang et al. 2014). In March 2022, a leaf spot disease in mung bean was observed at the Gangneung-Wonju National University Experimental farm (Gangneung, South Korea, 37.77°N, 128.86°E). The affected plants had irregular brown-gray leaf spots, and the bottom of the leaves showed concentric brown-gray rings that eventually progressed to necrotic lesions. Regardless of the cultivar, approximately 30% of the plants in the field were infected. To isolate the pathogen, the affected leaves were surface-sterilized by washing with 70% ethanol for 1 min, followed by washing with 2% NaClO for 2 min, then rinsing with sterile distilled water. We placed 3-mm sized diseased lesions on potato-dextrose agar (PDA), then incubated them at 27 ± 1 °C in the dark for 7 days and we obtained 1 isolate (CC1). The fungus on PDA had white aerial mycelia that became gray toward the center. Single spore cultures were obtained from fungal isolate. Isolated conidia were single celled, hyaline, cylindrical, and measured between 20.75 to 22.07 μm × 5.85 to 6.92 μm (n = 20), similar to other reports of C. camelliae(Wang et al. 2016). Mycelium from the single spore isolate was used for DNA extraction using Exgene™ Plant SV / (GeneAll®, Cat.No. 117-152), and we amplified the ITS region with primers ITS1 + ITS2 and ITS3 + ITS4, a portion of the actin gene with primers ACT-512F + 738R, and a portion of the beta-tubulin gene with primers BT2aF + BT2bR (Carbone et al. 1999; Glass et al. 1995; White et al. 1990). The amplified regions were sequenced by by Macrogen® (Seoul, South Korea). Sequences were deposited under GenBank accession numbers OR523262 (ITS), OR582483 (Actin), and OR566953 (beta-tubulin). MegaBLAST analysis of the ITS1, ITS2, ACT, and TUB regions showed 99% (216/217 bp) similarity with C. camelliae strain HNCS-26 (MK041440.1), 99% (303/305 bp) similarity with C. camelliae strain G3 (ON025203.1), 99% (242/244 bp) similarity with C. camelliae strain FWT41 (MN525820.1), and 99% (456/460 bp) with C. camelliae strain LF152 (KJ955239.1), respectively. To fulfill Koch's postulates, we conducted a pathogenicity teston the mung bean cultivar VC1973A (Seonhwanokdu) grown for four weeks at 25 °C with a 16-h day/8-h night cycle, simulating the field conditions when the symptoms were observed. We tested the pathogenicity on six plants , three control and three infected plants. Using three leaf replicates per plant resulting in total of nine leaves per group. Leaves were first injured using a sterile needle then either sterile 5 mm PDA plugs or plugs with C. camelliae were placed on the leaf for control and infected conditions, respectively. Irregular gray leaf spots were observed on the abaxial and adaxial of the infected leaf after 2 weeks, like the symptoms observed in the field. This was observed only on infected leaves and nowhere else on the plant and the control plants had no infection. We re-isolated the pathogen from diseased leaves and identified it as C. camelliae using the same molecular markers described previously, completing Koch's postulate. To the best of our knowledge, this is the first report of leaf spot caused by C. camelliae in mung bean plants in Korea, previously the fungi was reported to infect tea plants in Korea (Hassan et al. 2023). More studies are required to investigate potentially resistant mung bean varieties to minimize future damage caused by this fungus.

A Cluster of Peronospora parasitica 13-like (NBS-LRR) Genes Is Associated with Powdery Mildew (Erysiphe polygoni) Resistance in Mungbean (Vigna radiata).

Powdery mildew (PM) caused by Erysiphe polygoni is an important foliar disease in mungbean (Vigna radiata). A previous study showed that QTL qPMRUM5-2 is a major locus for PM resistance in mungbean accession RUM5 (highly resistant). Bioinformatics analysis revealed that flanking markers of the qPMRUM5-2 covered a region of 1.93 Mb. In this study, we conducted fine mapping for the qPMRUM5-2 using the F2 population of 1156 plants of the cross between Chai Nat 60 (CN60; highly susceptible) and RUM5. PM resistance evaluation was performed under field conditions using F2:3 lines grown in three different environments. QTL analyses consistently located the qPMRUM5-2 to a 0.09 cm interval on linkage group 6 between InDel markers VrLG6-InDel05 and VrLG6-InDel10, which corresponded to a 135.0 kb region on chromosome 8 containing nine predicted genes of which five were NBS-LRR-type genes Recognition of Peronospora parasitica 13-like protein (RPP13L). Whole-genome re-sequencing of RUM5 and CN60 showed polymorphisms in four RPP13L genes predictively cause substantial amino acid changes, rendering them important candidate genes for PM resistance. The InDel markers VrLG6-InDel05 and VrLG6-InDel10 flanking to the qPMRUM5-2 would be useful for marker-assisted breeding of PM resistance in the mungbean.

Management of Cercospora leaf spot disease in mungbean using novel fungicides, botanicals and bio-agent

Management of Cercospora leaf spot disease in mungbean using novel fungicides, botanicals and bio-agent

Arbuscular mycorrhizal fungi association and root rot disease in mungbean (<i>Vigna radiata</i>) growing areas of Haryana

The study was carried out during rainy (kharif) seasons of 2021 and 2022 at Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana to provide a comprehensive understanding of how the presence and activity of arbuscular mycorrhizal (AM) fungi may influence the development of root rot in mungbean (Vigna radiata L.) crops in different mungbean-growing areas of Haryana. Root colonization by AM fungi in Hisar, Bhiwani, Mahendragarh, and Charkhi Dadri districts of Haryana ranged from 16.45 to 24.07%, 7.71 to 16.73%, 7.02 to 21.43% and 7.59 to 22.28%, respectively. This variability underscores the diverse interactions between mungbean plants and AM fungi in these distinct geographical regions, reflecting the influence of environmental factors and local soil conditions on mycorrhizal associations. Sporocarp numbers in these districts ranged from 76.5 to 131.5, 37 to 102, 54 to 119.5 and 65.5 to 118 per 100 g of soil, respectively. These findings emphasize the dynamic nature of AM fungal populations and their potential impact on the overall soil health and plant-microbe interactions in mungbean cultivation. Similarly, root rot incidence in these districts varied from 6.59 to 11.62%, 7.48 to 11.29%, 7.05 to 11.43% and 5.88 to 11.76%, while root rot intensity ranged from 2.77 to 4.82%, 2.70 to 4.61%, 2.06 to 4.61% and 2.43 to 4.85% in Hisar, Bhiwani, Mahendragarh, and Charkhi Dadri districts, respectively. This variability in root rot incidence and intensity highlights the susceptibility of mungbean crops to this detrimental disease and emphasizes the importance of region-specific strategies for disease management.

Management of Cercospora leaf spot disease in mungbean using novel fungicides, botanicals and bio-agent

Management of Cercospora leaf spot disease in mungbean using novel fungicides, botanicals and bio-agent

Management of Macrophomina phaseolina (Tassi.) Goid. Causing Leaf Blight Disease in Mung Bean in Maharashtra State

Leaf blight (LB) disease caused by Macrophomina phaseolina, an important constraint in mung bean production in India. In the present investigations, the aimed to evaluate the loss in yield, better mung bean cultivars against LB and the efficient management. Based on symptomatology, cultural and morphological characteristics the pathogen isolated from cv JL-781 it was identified as M. phaseolina (Tassi.) Goid. inducing LB disease. Pathogenicity of M. phaseolina was proved on the mung bean cv JL-781. Subsequently, field experiment was conducted for the management of LB disease using seed treatment with carbendazim 50 WP a.i. 0.2% (2 g/kg) + spraying of zinc sulphate monohydrate @ 0.01% + soil application of Trichoderma viride @ 5 g/ha mixed with 3 kg of FYM + foliar spray of garlic extract (10%) showed 15.45% incidence. This result was followed by 16.79% disease incidence and 15.44% disease severity by seed treatment with carbendazim, foliar spray of zinc sulphate, and soil application with T. viride @ 5 g/ha mixed with 3 kg of FYM.

Unveiling the Factors Affecting Leaf Spot Disease in Mungbean and its Management

Unveiling the Factors Affecting Leaf Spot Disease in Mungbean and its Management

Evaluating molecular diagnostic techniques for seed detection of Pseudomonas savastanoi pv. phaseolicola, causal agent of halo blight disease in mungbean (Vigna radiata)

Halo blight of mungbean (Vigna radiata var. radiata) is caused by the bacterium Pseudomonas savastanoi pv. phaseolicola. This pathogen is transmitted via infected seed, facilitating the spread of the disease into new cultivated areas. Prospective mungbean seed crops are currently subjected to visual inspection as a means of determining disease status, however, this is a poor method that relies on visible symptoms and does not account for latent infections. A range of molecular diagnostics targeting P. savastanoi pv. phaseolicola have been developed, but these have not been deployed on seeds. Quantitative PCR (qPCR) SYBR assay, hydrolysis probe, and conventional PCR, using the same primers were optimised against a plate-truthed dilution series of P. savastanoi pv. phaseolicola. The detection limit of the conventional PCR assay was approximately 9,000 CFU µl-1, while both qPCR assays could detect 9 CFU µl-1. These tests were then used to screen DNA extracted from 200 g allotments of 38 seed lots comprising six mungbean cultivars representing the primary Australian production area, and two seed lots of known infection status. Of these, the pathogen was detected in six seed lots by conventional PCR. The SYBR assay and hydrolysis probe methods detected 20 and 24 infected seed lots respectively. This shows that the hydrolysis probe method was the most effective at diagnosing the presence of P. savastanoi pv. phaseolicola in mungbean seed, providing a valuable molecular diagnostic to aid in integrated disease management and seed certification, substantially mitigating losses to halo blight disease.

New Report of Cercospora canescens Isolates from Coastal Regions of Odisha, India causing Cercospora Leaf Spot (CLS) Disease in Mung Bean (Vigna radiata L.)

Background: Cercospora leaf spot (CLS) is one of the major diseases causing a major loss in production of mung bean of up to 60%. Although it is cultivated all round the world, its major contribution is attributed to the Asian continent especially the countries of Indian subcontinents which accounts for about 90% of the world’s mungbean production. Due to its high nutritional content, mung bean is a major contributor to the Nation’s economy. The present study was to isolate and characterize the new isolates of Cercospora canescens collected from coastal belts of Odisha, India. Methods: Surveys were conducted in the mung bean growing fields of Bhubaneswar (20.26°N, 85.8°E) and Berhampur (19.36°N, 84.77°E), coastal regions of Odisha during 2018-20. New Cercospora canescens isolates were collected and characterised through morphological, biochemical and molecular basis. Result: New Cercospora isolates were characterized on the basis of morphological, biochemical and molecular analysis to understand the gravity of the disease. Pathogenicity tests were conducted by artificial inoculation to identify the resistant and susceptible mung bean genotypes. On the basis of molecular analysis (internal transcribed spacer (ITS) region), there was a difference between the two isolates and forming different clades. These isolates were sequenced having the NCBI Acc. No. MZ475049 and MZ475050. Both isolates are different from each other because of transitional substitution of thymine and cytosine. The findings will be a complementary contribution for conservation and better management strategies of CLS disease in mung bean.

Identification of mung bean germplasm for resistance against Cercospora canescens and to study the association of biochemical parameters with defense mechanisms

AbstractSizable loss in crop yields resulting from Cercospora leaf spot (CLS), caused by Cercospora canescens and is a major disease in mung bean [Vigna radiata (L.) R. Wilczek] crops, demands a thorough evaluation of various parameters dealing with the infection. Determination of components for CLS resistance is associated with leaf spot intensity in the field, which is estimated from the area under the disease progress curve (AUDPC). The present study showed that out of 261 genotypes screened in the field for CLS, 88, 89, 51 and, 33 genotypes were found to be resistant, moderately resistant, moderately susceptible, and susceptible, respectively, on the basis of the AUDPC values. Further, five resistant and five susceptible genotypes were selected from the screened genotypes for bioassay analysis and were subjected to artificial inoculation with three different isolates of Cercospora canescens to study the effectiveness in polyhouse. The morphological data along with disease incidence, chlorophyll content, proline content, phenol content and enzymatic activities of phenylalanine ammonia‐lyase (PAL), peroxidase (POX), and superoxide dismutase (SOD) were estimated. The findings showed that there was a significant increase in the enzymatic activities, total phenol, and proline contents in inoculated resistant and susceptible genotypes vs. control (without inoculation). However, the total chlorophyll content reduced in both resistant and susceptible genotypes after inoculation. Moreover, higher enzyme activities were marked in the resistant genotypes than the susceptible genotypes. This study will help to identify the resistant and susceptible mung bean genotypes against Cercospora canescens for further agronomic study as well as breeding programs.

Integrated disease management strategies against leaf spot and root rot diseases of mungbean

Integrated disease management strategies against leaf spot and root rot diseases of mungbean

Evaluation of Suitable IPM Module for Management of YMV Disease in Mungbean under West Central Table Land Zone of Odisha

Background: YMV disease in mungbean is one of the major disease causing heavy losses annually throughout the country. As the disease is transmitted by insect vector, management of vector is important to check the YMV disease that can minimise the losses. The present investigation was aimed to evaluate different IPM modules for management of YMV disease of mungbean. Methods: Field experiments were carried out during Rabi season of 2016-17 and 2017-18 at the Research Farm of Regional Research and Technology Transfer Station, Chiplima, Sambalpur, Odisha, India. Population of whitefly was recorded on three leaves selected from top, middle and bottom canopy of the plant. Disease severity was recorded by using 0-9 scale. Result: The IPM module i.e. seed treatment with Thiamethoxam 25 WG @ 5 gm kg-1 of seed, installation of yellow sticky trap @ 50 ha-1 and spraying of Acetamiprid 20 SP @ 0.3 gm l-1 of water was found as the most effective among all other modules. Pooled analysis of two years data revealed that 65.5% YMV disease control and 59.3% reduction of white fly population over control were performed by the said IPM module. A maximum increase in yield (84.8%) and highest cost benefit ratio (1.77) were also achieved with the module.

A Novel Disease of Mung Bean, Phytophthora Stem Rot Caused by a New Forma Specialis of Phytophthora vignae.

An emerging soilborne disease resembling Phytophthora stem rot was observed on mung bean plants grown in Anhui, China. To identify the causal agent, diseased plants and soil samples from 13 fields were collected to isolate the pathogen. Twenty-two Phytophthora isolates were recovered from the samples and detailed identification was conducted. Based on morphological and molecular characterizations, all of the isolates were consistently identified as P. vignae. Phylogenetic analysis using eight nuclear loci sequences of the internal transcribed spacer region, rRNA gene large subunit, a partial sequence of the β-tubulin gene, translation elongation factor 1α, 60S ribosomal protein L10, the enolase gene, heat shock protein 90, and triose phosphate isomerase/glyceraldehyde-3-phosphate dehydrogenase and a mitochondrial locus cytochrome c oxidase subunit I revealed that the mung bean isolates grouped in the same clade as P. vignae and its two formae speciales, P. vignae f. sp. adzukicola and P. vignae f. sp. vignae. A host specificity test showed that the mung bean isolates of P. vignae were pathogenic toward mung bean with a much stronger virulence and toward adzuki bean with a relatively weak virulence, but they were nonpathogenic to the other tested legume crops, including soybean, cowpea, pea, common bean, faba bean, and chickpea. The host range of mung bean isolates significantly differs from those of P. vignae f. sp. adzukicola and P. vignae f. sp. vignae based on our results and on previous studies. Thus, the pathogen causing Phytophthora stem rot of mung bean is proposed as a new forma specialis of P. vignae, designated as P. vignae f. sp. mungcola.

Halo Blight of Mungbean in Australia

Halo blight, one of the major diseases of mungbean, is caused by the bacterium Pseudomonas savastanoi pv. phaseolicola. The pathogen infects the foliar parts of the plant, causing water-soaked spots that eventually develop surrounding yellow margins. The disease is particularly destructive under moderate temperature and high humidity, especially when it occurs during late vegetative through to early reproductive stage. In such conditions, severely infected crops could experience a yield loss up to 70%. Halo blight can be widespread on mungbeans grown in Southern Queensland and Northern New South Wales. However, due to its seedborne and cryptic nature of transmission, the disease is likely to be under-reported. This report addresses major aspects of halo blight symptomology, pathology and epidemiology.

Genetic Diversity Analysis and Validation of Microsatellite Markers Linked with Tolerance to Powdery Mildew Disease in Mungbean [Vigna radiata (L.) Wilczek

Background: Mungbean [Vigna radiata (L.) Wilczek] is a self-pollinated diploid grain legume (2n=2x=22) crop and has a genome size of 560 Mb. The present study was concentrate to portray the nature and extent of genotypic variation exists among mungbean collections for a range of traits of potential agronomic and adaptive interests. Many diseases affect mungbean, causes the major constraint in the increasing production among which Powdery mildew disease caused by Erisyphepolygoni is economically significant because it reduces photosynthetic activity and physiological changes which results in 20-40 per cent reduction in yield. Some gene-specific marker were analysed and found associated with powdery mildew resistance in mungbean genotypes.Methods: The present investigation was carried out to evaluate thirty-one mungbean genotypes (including four checks) collected from the different parts of India. The genotypes were sown in an incomplete augmented bock design along with four checks varieties. viz. ‘Kamdev’, ‘OBBGG-52’, ‘IPM-02-14’ and ‘IPM-02-3’. All the mungbean genotypes were evaluated for different phenotypic traits and their tolerance to powdery mildew disease at two cropping seasons as well as at two different locations in Odisha. In this investigation, seven molecular markers viz., VrCSSTS1, VrCSSTS2, VrCSSSR3, CEDG191, MB-SSR238, CEDG166, CEDG282 were analysed.Result: SSR marker such as VrCSSSR and VrCSSTS linked with powdery mildew resistance gene were tested in different genotypes with known powdery mildew reaction and the results showed a consistent association of the marker in all the powdery mildew resistant genotypes and absent in all the powdery mildew susceptible genotypes. The results confirmed the validation of these markers with the powdery mildew resistance gene in different genetic backgrounds. Similarly, CEDG191, CEDG166, CEDG282 markers, reported to be linked to powdery mildew resistance, amplified the respective marker fragment of 100 to 300 bp in mungbean genotypes and were polymorphic. The above PCR-based and locus-specific markers could be employed for marker-assisted breeding (MAB) program as well as genotype conservation. These linked markers will boost the efficiency and precision of powdery mildew resistance breeding in mungbean.

Fine mapping of QTL conferring Cercospora leaf spot disease resistance in mungbean revealed TAF5 as candidate gene for the resistance.

This paper reports fine mapping of qCLS for resistance to Cercospora leaf spot disease in mungbean and identified LOC106765332encoding TATA-binding-protein-associated factor 5 (TAF5) as the candidate gene for the resistance Cercospora leaf spot (CLS) caused by the fungus Cercospora canescens is an important disease of mungbean. A QTL mapping using mungbean F2 and BC1F1 populations developed from the "V4718" (resistant) and "Kamphaeng Saen 1" (KPS1; susceptible) has identified a major QTL controlling CLS resistance (qCLS). In this study, we finely mapped the qCLS and identified candidate genes at this locus. A BC8F2 [KPS1 × (KPS1 × V4718)] population developed in this study and the F2 (KPS1 × V4718) population used in a previous study were genotyped with 16 newly developed SSR markers. QTL analysis in the BC8F2 and F2 populations consistently showed that the qCLS was mapped to a genomic region of ~ 13Kb on chromosome 6, which contains only one annotated gene, LOC106765332 (designated "VrTAF5"), encoding TATA-binding-protein-associated factor 5 (TAF5), a subunit of transcription initiation factor IID and Spt-Ada-Gcn5 acetyltransferase complexes. Sequence comparison of VrTAF5 between KPS1 and V4718 revealed many single nucleotide polymorphisms (SNPs) and inserts/deletions (InDels) in which eight SNPs presented in eight different exons, and an SNP (G4,932C) residing in exon 8 causes amino acid change (S250T) in V4718. An InDel marker was developed to detect a 24-bp InDel polymorphism in VrTAF5 between KPS1 and V4718. Analysis by RT-qPCR showed that expression levels of VrTAF5 in KPS1 and V4718 were not statistically different. These results indicated that mutation in VrTAF5 causing an amino acid change in the VrTAF5 protein is responsible for CLS resistance in V4718.

Influence of Temperature on the Pathogenesis and Gene Expression of Rhizoctonia solani Causing Web Blight/Wet Root Rot Disease in Mungbean

Background: Mungbean (Vigna radiata L. Wilzeck) is one of the most important pulse crops and grown in almost all parts of the India. Web blight/wet root rot disease of mungbean is caused by Rhizoctonia solani Kühn. Crop environmental factors plays a vital role in the development of web blight disease caused by R. solani. An understanding of the role of environmental factors on the infection and survival of the pathogen is necessary to develop disease management practices. Methods: The effect of different temperatures (4oC, 20oC, 25oC, 30oC and 35oC) on mycelial growth of seven different R. solani isolates belonging to different anastomosis group were evaluated under in vitro conditions. Effect of different temperatures on the development of root rot/web blight disease of mungbean was also evaluated under phytotron conditions at various temperatures with constant relative humidity (85%) and illumination (alternate dark and light period of 12 h). Effect of temperatures on the expression of selected pathogenicity related genes was evaluated through real time PCR. Result: Maximum radial growth in R. solani isolates was observed at 25 and 30oC after 48 hrs of incubation. Maximum disease incidence was observed with R. solani isolate RUPU-18 (73.11%) followed by R-17 (68.75%), RDLM-1 (63.45%) at 25oC on mungbean genotype Pusa Vishal. Expression of genes like ABC transporter was observed only at 35oC, while other genes like 1, 3 glucan hydrolase expressed maximum at 25oC after 24, 48 and 72 hrs post inoculation. Present study suggested that the expression of pathogenicity related genes in mungbean-R. solani system is dependent on the temperature and time interval post pathogen inoculation.

Development of Mungbean yellow mosaic virus Resistant Genotypes in Mungbean through Interspecific Crosses of Wild Vigna Species

Mungbean Yellow mosaic disease is a main destructing viral disease in mungbean caused by Mungbean yellow mosaic virus (MYMV) which leads to severe sometime 100 percent yield reduction and it necessitates for developing MYMV resistant lines. The present investigation was carried out with an objective of evolution of MYMV resistant progenies through incorporating wide genes of same genera. An attempt was made between V. radiata x V. umbellata crosses. This agroinoculation technique was employed to examine the F2 individuals, which were derived from a cross between VMGG012-005 (Moderately susceptible) x VGGru1 (resistant homozygous advanced line from Vigna radiata x Vigna umbellata derivative used as MYMV donor) to screen for the MYMV resistant progenies. In the field condition, MYMV infection can be evaluated by MYMV disease rating scale (1-9).