Mungbean Yellow Mosaic Virus Disease Research Articles

Induced mutagenesis for resistance to mungbean yellow mosaic virus and yield traits in mungbean

The M0 ѕeedѕ of mungbean variety DGGV 2 treated with different doѕeѕ of ethyl methane ѕulphonate (EMЅ) at 0.1%, 0.2% and 0.3% concentrations were assessed for Mungbean Yellow Mosaic Virus (MYMV) in M2 generation during summer 2023 at University of Agricultural Sciences, Dharwad. Considering the yield superiority over check (Mean + 2 Standard Deviation) and highly resistant response to MYMV disease, out of 962 M2 plants 17 superior M2 plants were identified. The seed yield plant-1 in these identified mutants ranged from 21.9 to 32.0 g which is higher compared to the average yield of check DGGV 2 (11.7 g) during that season. Also, the other yield contributing traits such as number of productive branches, number of cluster plant-1, number of pods cluster-1, and number of pods plant-1 were observed to be higher in these mutants in comparison to check variety.

Assessing the Performance of Latest Greengram Varieties under Improved production Packages in Thiruppur, Tamil Nadu, India

On Farm Testing (OFT) in Mungbean Yellow Mosaic Virus (MYMV) resistant and high yielding greengram varieties was conducted by Krishi Vigyan Kendra, Tamil Nadu Agricultural University, Tirupur in farmers field during kharif 2020. Totally 15 farmers each with one acre were selected in three villages of Pongalur Block in Tirupur district of Tamil Nadu. Critical input viz., seeds of greengram varieties CO 8 and DGG 1 were distributed to the farmers and the varietal performance were assessed along with the existing variety under cultivation VBN 2. The plant physiological parameters viz., plant height, number of nodules / plant and yield attributing parameters such as number of pods / plants, number of branches/plant, Mung bean Yellow Mosaic Virus (MYMV) disease incidence (%), yield (q ha-1) and B:C ratio were recorded. The results revealed that, among the three varieties, Greengram CO 8 was recorded more number of pods (42) and minimum incidence of Mungbean Yellow Mosaic Virus (MYMV) disease incidence of 3.2 per cent resulting in the highest yield of 9.5 q ha-1 followed by DDG 1 with 34 pods/plant, MYMV disease incidence of 7.3 per cent and yield of 8.4 q ha-1 compared to the existing variety VBN 2, which recorded the lowest number of pods (31 Nos.), yield (7.6 q ha-1) with the highest MYMV disease incidence (12.5%). The highest B:C ratio was recorded in greengram variety CO 8 (2.92) which was followed by DDG 1 (2.58). It was concluded that, farmers of Tirupur district in Tamil Nadu were satisfied with cultivation of greengram CO 8 variety due to the lowest disease incidence, higher yield and Benefit Cost Ratio.

Development of bruchid pest and mungbean yellow mosaic virus disease resistance lines in blackgram [Vigna mungo (L.) Hepper] through marker- assisted selection

Bruchid beetles (Callosobruchus maculatus) and mungbean yellow mosaic virus (MYMV) disease are the two major causes of yield constraints in blackgram. Marker-assisted selection was performed among a population developed from the cross combinations of MDU 1 (susceptible female parent) and the TU 68 (resistant male parent) to select for bruchid and MYMV disease resistance. The selected introgression lines (ILs) were significantly superior for bruchid and MYMV disease resistance traits. The introgression lines namely IL-9-1, IL-12-1, IL-12-2, IL-12-7, IL-12-9 and IL-12-10 recorded higher seed yield during the disease prevalent environment than the female parent MDU 1. But the yield performances were lower than the female parent MDU 1 in the disease-free environment. The reduced performance for yield might be due to the linkage drag among the introgression lines. Hence, the linkage drag can be eliminated by the backcross breeding method. However, the successful selection for dual biotic resistance was achieved among the introgression lines. Further, better recombinants must be isolated to obtain good yielding variety and bruchid and MYMV disease resistance.

Epidemiology and Management of MYMV Disease in Mung Bean (Vigna radiata (L.))

Mung bean is a short-duration ancient legume crop that can be grown as a sole or intercrop for grain and green manure in all three crop seasons, including winter, summer and rainy in various regions of the country. MYMV (Mungbean Yellow Mosaic Virus) disease is one of the most destructive diseases transmitted by whitefly (Bemisia tabaci Genn) persistently. Weather parameters have no direct effect on MYMV, but affect the whitefly population. Field experiments were conducted for three consecutive years from 2019-2021 as to know the effect of weather parameters on the whitefly population. Development of whitefly population and MYMV disease severity were recorded in mungbean crops at 7 days interval starting from 20 days after sowing (DAS). The present study showed that whitefly population builds up starting in July and reached to maximum at end of August to early September. There are various factors influencing the build-up of whitefly population viz., maximum temperature 36±2°C, minimum temperature 25±2°C, morning relative humidity more than 90 percent, more sunshine hours and no rainfall prevailing during that period. Whitefly population had positive significant correlation with maximum temperature and bright sunshine hours while evening relative humidity and rainfall were recorded as negatively significant. Three-year data is very helpful in guiding the farmers for timely and preventive sprays based on existing infections and the population of whitefly in a season.

Influence of meteorological parameters on incidence of mungbean yellow mosaic virus disease in green gram in Assam

Green gram (Vigna radiata) is one of the most important pulse crops grown in India and abroad bean yellow mosaic virus disease caused by Mung bean yellow mosaic virus has become a major threat in greengram cultivation in Assam. An experiment was conducted in the Experimental field, Department of Plant Pathology, Biswanath College of Agriculture, Assam Agricultural University, Biswanath Chariali during 2021-22, where green gram was sown in five dates starting from 5th September 2021to 3rd October 2021 at 7 days interval to study the effect of meteorological parameters in the incidence of green gram yellow mosaic virus disease, effect on growth and yield parameters so as to find out the best sowing time of the crop as a strategy for managing the disease. During the study, symptoms like, appearance of chlorotic specks along the veins, puckering of leaves, typical mosaic pattern, complete yellowing and drying of the leaves were recorded. Highest whitefly population (12.42 no/plant) was recorded in the crop sown on 19.09.2021 and the lowest (6.24no/plant) was recorded in the 05.9.2021 sown crop. Lowest (40.32%) disease incidence with highest seed yield (4.50 q/ha) was recorded in the crop sown on 05.09.2021, whereas highest (88.25%) disease incidence with lowest yield (2.50 q/ha) was recorded in the crop sown in second fortnight of September (19.09.21). Maximum temperature ranging from 29-33 oC, minimum temperature 13-23 oC with 8-9 bright sunshine hours were found to be conducive for incidence and rapid spread of the disease.

Validation of IPM Modules for the Management of Whitefly, Bemisia tabaci and Mungbean Yellow Mosaic Virus Disease in Greengram

Greengram is known to be infected by several viral diseases. Among them, Mungbean Yellow Mosaic Virus (MYMV) is the most destructive in India, and it is popularly known as the yellow plague. MYMV transmitted exclusively through plant-to-plant by whitefly, Bemisia tabaci (Gennadius). For the management of MYMV, vector control is the only possible option. Hence, the attempt was made to evaluate IPM modules against whiteflies by reducing their population or disrupt MYMV transmission. The field experiment was conducted at Agricultural and Horticultural Research Station, Bhavikere, during the Kharif seasons of 2018 and 2019. The results of two seasons indicated that, the lowest whitefly population (1.70 per trifoliate leaf) and significantly lowest MYMV incidence was recorded in module-3 (Maize as a border crop + one spray of NSKE 5 % at 20 days after sowing + one spray of fish oil rosin soap @ 5ml/liter at 40 DAS). The highest grain yield (9.64 q/ha) and cost: benefit ratio (1: 3.23) was recorded in this module, followed by module-1 (Maize as a border crop + Seed treatment with imidacloprid 600 FS @ 5 ml per kg of seeds). For the management of MYMV and its vector whitefly, B. tabaci module-3 was effective compared to the standard check (Dimethoate 30 EC at the rate of 1.75 ml per liter). The importance of IPM in whitefly management to reduce virus incidence is discussed.

Prediction of mungbean yellow mosaic virus disease using multiple regression models

BackgroundThe main cause for low mungbean [Vigna radiata (L.) R. Wilczek] productivity is mungbean yellow mosaic virus (MYMV). Generally, the management of MYMV relies upon frequent insecticide sprays to control its vector (whitefly) and genetic resistance. However, disease forecast models can help to economize the pesticide sprays. Hence current study was designed to identifying environmental factor that promote disease development and developing a disease prediction model. MethodsOne hundred and twenty-seven mungbean accessions were planted for two years (2012 and 2013) and infection was dependent on natural inoculum. Weekly and daily data on disease incidence and environmental variables were collected and analyzed using correlation and stepwise regression analysis. ResultsWind velocity and high temperature had a negative relation with disease occurrence during both years, whereas low temperature, rainfall, and relative humidity, had positive relationship based on linear regression. The environmental conditions responsible for the highest disease incidence were, maximum temperature (32–34 °C), relative humidity (72–75 %), minimum temperature (27–29 °C), rainfall (1.8–2.1 mm) and wind velocity (3–4.5 km/hr) during both growing seasons Overall, five environmental variable multiple regression model encompassing relative humidity, wind speed, rainfall, suboptimum temperature, and optimum temperatures accommodate the data rightly explaining 83 % variation in disease outgrowth. ConclusionThe observed MYMV disease occurrence values for most of the mungbean genotypes, and those predicted by the model were very close. This multi-environmental variable model can be utilized to provide early warning forecasts for the management of MYMV in Pakistan.

Biotechnological Initiative for Management of Mungbean Yellow Mosaic Virus in Mungbean (Vigna radiate L.)

Mungbean (Vigna radiate L.) is one of the most important legume crops of Asiatic region. The average yield of mungbean is quite low due to its susceptibility against mungbean yellow mosaic virus (MYMV). Mungbean yellow mosaic virus disease (MYMD) is caused by MYMV, which is transmitted through whitefly (Bemisia tabaci). The controlling of this devastating disease is mainly depends upon spraying of insecticides, which cause serious ill effect on humans and soil health. Breeding for its resistance is one of the best strategies for developing MYMV resistant genotypes in mungbean. Several types of molecular markers have been used in marker assisted breeding (MAB) in mungbean. Among them SSR markers are widely used and a plethora of scientific advocate the use of the SSR marker in developing MYMV resistance in mungbean. Recent advancements in functional genomics and gene editing technologies can further enhance our understanding of the molecular mechanisms underlying resistance to MYMV and hence facilitate the development of MYMV resistant mungbean genotypes.

Blackgram CO 7: A new high yielding and bold seeded variety suitable for Tamil Nadu

Blackgram (Vigna mungo L.) is an important pulse crop in Tamil Nadu. An inter sub- specific cross was made VBN (Bg) 5 x V. mungo var. silvestris (22/10) to develop high yielding variety with yellow mosaic disease resistance. A high yielding blackgram culture (COBG 10-05) was identified and evaluated in different yield trials from 2012 to 2020. The culture matures in 60 - 65 days. It recorded an overall mean yield of 881 kg/ha which is 12.1 , 12.4 and 14.4 per cent yield increase over the check varieties viz., CO 6 (786 kg/ha) , VBN 6 (784 kg/ha) and VBN 8 (770 kg/ha), respectively. This culture is resistant to mungbean yellow mosaic virus disease and moderately resistant to leaf crinkle and stem necrosis diseases. It has bold seeds with 100 seed weight ranged from 5.5 to 6.0 g. The plant type is determinate with synchronized maturity and suitable for single/mechanical harvest. It contains 22.3 per cent protein. This culture was released as Co 7 and it is recommended for cultivation during kharif and rabi seasons in Tamil Nadu. Keywords : Blackgram, CO 7, High yield, Bold seeds, MYMV disease resistance

Novel and stable QTL regions conferring resistance to MYMV disease and its inheritance in blackgram (Vigna mungo (L.) Hepper)

Mungbean yellow mosaic virus (MYMV) disease is a significant constraint for blackgram production. The present study employed a mapping population derived from a cross between susceptible (MDU 1) and resistant (TU 68) genotypes to identify quantitative trait loci (QTL) associated with MYMV disease resistance in addition to bruchine resistance loci identified from the previous study. Phenotyping was carried out in F2 generation under the disease spreader row method at field condition. Disease score observations were carried out 60 days after sowing (DAS). The chi-square goodness of fit test revealed inhibitory gene action with two genes controlling the expression of resistance to MYMV disease. However, QTL analysis revealed one major QTL region, i.e. qMYMVD_60 at LG 10 responsible for MYMV disease score at 60 DAS, accounted for 21 per cent of variation. The identified QTL has the flanking markers as CEDG180 and CEDG116. Hence, the QTL, qMYMVD_60 may be utilized in the breeding of MYMV disease resistance. Further, the marker-assisted introgression of both the MYMV and bruchine resistance QTLs can be performed in the near future.

Marker-assisted backcross breeding for enhancing Mungbean Yellow Mosaic Virus (MYMV) disease resistance in blackgram [Vigna mungo (L.) Hepper] cv MDU 1

Mungbean yellow mosaic virus (MYMV) disease is the major disease of blackgram that affects crop growth and yield under severe epiphytotic conditions. Marker assisted backcross (MABC) breeding was employed to introgress the MYMV disease resistance Quantitative Trait Loci (QTL) regions from resistant donor Mash 1008 into the popular blackgram variety MDU 1. The MABC approach was applied to introgress two major QTL on linkage groups 2 and 10 into elite line MDU 1. All F1 were resistant to MYMV, so the resistance is dominant. After a series of two backcrosses and subsequent selfing, a total of 185 BC2F2 lines were obtained from the cross MDU1 x Mash 1008. Among them, three BC2F2 lines were identified with introgression of both QTL regions. A genome recovery of up to 63.80% was observed among these introgression lines. These introgressed lines were forwarded as single plants for further field evaluation. Finally, nine advanced backcross lines viz., BIL-4-47-1, BIL-4-47-3, BIL-4-47-4, BIL-4-47-5, BIL-4-47-7, BIL-4-47-8, BIL-4-47-9, BIL-4-47-10 and BIL-5-10-4 were found with significant superior performances over MDU1 for yield and MYMV disease resistance. These lines can be further evaluated in large scale trials to prepare their release as variety.

Salicylic Acid Induced Resistance against Mungbean Yellow Mosaic Virus (MYMV) and Enhanced Seed Yield in Resistant and Susceptible Urdbean [Vigna mungo (L.) Heper] Genotypes

Background: Urdbean’s low productivity is largely due to its susceptibility against whitefly-transmitted mungbean yellow mosaic virus (MYMV) disease. The effect of Salicylic acid (SA) on MYMV disease resistance and its impact on seed yield under field conditions on diverse genotypes is largely unknown. Therefore, in present investigation, we have analysed the effect of SA on induction of antioxidant enzymes leading to MYMV resistance and enhanced seed yield in urdbean genotypes. Methods: Different concentrations of SA were sprayed on 3 week-old susceptible urdbean genotype (LBG 623) and induction of antioxidant enzymes was analysed. A pot experiment was conducted to see the effect of SA on initial induction of antioxidant enzymes maintained over long period of time in 39 urdbean genotypes. Under field conditions, the effect of SA treatment on MYMV disease resistance and seed yield was assessed. Result: Rise in antioxidant enzyme production was observed in SA treated urdbean plants challenged with MYMV. The field experiment revealed that exogenous SA application significantly reduced MYMV incidence and increased seed yield in all 39 urdbean genotypes tested. The ability to confer MYMV resistance along with the increase in seed yield suggests the incorporation of SA in effective MYMV management strategies in urdbean.

Inheritance Pattern of Mungbean Yellow Mosaic Virus (MYMV) Disease Resistance in Blackgram [Vigna mungo (L.) Hepper

Background: Mungbean yellow mosaic virus (MYMV) disease is the most destructive disease in blackgram. Development of MYMV resistant varieties is one of the best possible solutions to avoid the yield reduction in blackgram. There are conflicting reports on the genetics of resistance to MYMV disease claiming that it is controlled by both dominant and recessive genes. Hence the present study was aimed to understand the inheritance pattern of the MYMV disease resistance in eight crosses of blackgram.Methods: Parents, F1 and F2 generation of eight cross combinations were raised during July - Sep, 2018 at National Pulses Research Centre, Tamil Nadu Agricultural University, Vamban, Tamil Nadu. An infector row of CO 5 was raised to intensify the MYMV disease pressure after every eight rows. Based on disease incidence on 60th day after sowing, two phenotypic classes were formed among F2 plants with the scales of (1 to 3) as resistant phenotype and (4 to 9) as susceptible phenotype. The goodness of fit to Mendelian segregation ratio for MYMV disease resistance in the segregating population was tested by Chi square test (Stansfield, 1991).Result: The MYMV disease incidence was tri-genically controlled with inhibitory gene action in four crosses viz., MDU 1 x Mash 114, CO5 x Mash 114, MDU 1 x VBN 6 and CO 5 x VBN 6. Complementary gene action with two genes was observed in four crosses viz., MDU 1 x Mash 1008, CO 5 x Mash 1008, MDU 1 x VBN 8 and CO 5 x VBN 8. Differences in number of genes were observed due to the presence of recessive inhibitory gene in both male and female parents of the crosses which had complementary gene action for MYMV disease. The putative gene symbols assigned for the six genotypes viz., S1S1S2S2ii (MDU 1 and CO 5), s1s1s2s2II (Mash 114 and VBN 6) and s1s1s2s2ii (Mash 1008 and VBN 8), respectively.

Interspecific Hybridization Between Vigna radiata and Vigna mungo Towards the Broadening of Genetic Base for MYMV Disease Resistance and Generating Variability

Background: The main cause for low yield in greengram is its susceptibility to Mungbean Yellow Mosaic Virus (MYMV) which is the most prevalent and destructive viral pathogen cause 85% yield lose. Inter specific hybridization between Vigna radiata and Vigna mungo could be an alternate approach to develop MYMV resistant genotypes in greengram which leads to additional source of creating variability for desirable attributes including yield, nutritional quality, biotic and abiotic stresses.Methods: The present investigation was carried out at National Pulses Research Centre (NPRC), Tamil Nadu Agricultural University, Vamban during 2016-2017. Interspecific hybridization has been effected between Vigna radiata var. VBN (Gg)2, VBN (Gg) 3 (as females) and Vigna mungo Var. Mash 114 (as male) during Summer 2016. The interspecific F1 hybrids, F2 and F3 populations were evaluated during Kharif 2016, Rabi 2016-17 and summer 2017 respectively. The F2 and F3 populations were evaluated for days to 1st flowering, days to maturity, plant height (cm), number of branches / plant, number of clusters / plant, number of pods / clusters, pod length (cm), number of seeds / pod, number of pods / plant, single plant yield (g.). The MYMV resistance has been confirmed under infector row method using CO 5 as susceptible check variety. Phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV), Heritability (h2) in broad sense, genetic advance as per cent of mean, Skewness and Kurtosis were estimated for yield and yield components. Result: Four true F1 plants were recovered in Vigna radiata var. VBN (Gg)2 x Vigna mungo Var. Mash 114 cross combination. The fertile F1 had the shallow lobbed leaf of Vigna radiata var. VBN (Gg)2 and black colour seed of Vigna mungo var. Mash 114 with pollen fertility of 42.0 per cent and crossability of 12.50%. Most interestingly all the four interspecific F1 plants were free from MYMV disease. In F2 generation, only one healthy plant was survived which had a pod, stem and branching behaviour of blackgram and greengram characters of lobbed leaf and green seed colour. In F3 generation, number of branches per plant, number of clusters per plant, number of pods per plant, pod length and seed yield per plant had high GCV, high PCV, high heritability coupled with high genetic advance as per cent of mean. Present study suggests that MYMV resistant cultivars of greengram can be explored through interspecific hybridization with Vigna mungo var. Mash 114 as a source of resistance and the hidden transgressive segregants can be recovered in F3 generation.

Morpho-physiological and Biochemical Variability in Greengram [Vigna radiata (L.) Wilczek] Varieties for Mungbean Yellow Mosaic Virus (MYMV) Resistance under Natural Field Conditions

Background: Mungbean yellow mosaic virus (MYMV) is economically most important disease of greengram reducing grain yields by 20-70%. Whiteflies and thrips are the most important insect pests which transmit the viral diseases MYMV and LCV respectively. The host plant resistance to MYMV disease in greengram genotypes has a great importance. The morpho-physiological and biochemical traits play an important role in host plant resistance against MYMV disease through insect vector resistance.Methods: A field experiment was conducted during rabi 2017-18 and 2018-19 at RARS Lam Guntur in a randomized block design with eight greengram genotypes and replicated thrice under receding soil moisture condition. The experiment was conducted using eight greengram varieties (WGG 42, Pusa Vishal, LGG 607, LGG 630, LGG 601, LGG 610, LGG 460 and LGG 450) obtained from RARS Lam Guntur and the genotype LGG 450 was considered as a susceptible check. The estimation of sugars, phenols, tannins, trichome density and SCMR was done at vegetative and reproductive stages of crop growth.Result: A significant variation was observed among the varieties for all the traits observed at vegetative and reproductive growth stages during both rabi 2017-18 and 2018-19. The total sugar content of the greengram varieties varied from 25.55 to 47.32 mgg-1 FW; the leaf phenolic content values ranged from 12.09 to 26.83 mg g-1 FW and the tannins content of the dried leaf samples ranged from 0.020 to 0.055 mgg-1 DW. The Trichome density of the greengram varieties varied from 75 to 162/cm2 of leaf area and the SCMR values ranged from 35.12 to 58.67. Higher seed yield was recorded in the variety LGG 630 followed by WGG 42 and the lower seed yield was recorded in the variety LGG 450 during rabi 2017-18 and 2018-19. The MYMV resistant varieties showed relatively higher phenolic, tannins content and trichome density and lower total sugar content in the leaf. The total sugar content showed a significant negative correlation with the seed yield. The SCMR value was significantly lower in the susceptible varieties of greengram with higher disease scores.

Identification and Validation of Quantitative Trait Loci of Mungbean Yellow Mosaic Virus Disease Resistance in Blackgram [Vigna mungo (L). Hepper

Background: Blackgram [Vigna mungo (L.) Hepper] is an important food legume crop of India. Mungbean yellow mosaic virus (MYMV) disease is the major problem in blackgram. The disease can reduce seed yield upto 100% or even kill a plant infected at an early vegetative stage. The most effective way to prevent the occurrence of this disease is to develop genetically resistant cultivars of blackgram. However, a major difficulty in breeding MYMV disease resistant in blackgram is field screening for the virus disease. Hence identification of QTL followed by Marker-assisted selection (MAS) is highly useful for genetic improvement of crops. With this background, a study was made for identification as well as validation of quantitative trait loci (QTL) for MYMV disease resistance in blackgram.Methods: A total of 112 F2:3 lines were evaluated for MYMV disease resistance along with parents viz., MDU 1 (MYMV disease susceptible) and Mash 1008 (MYMV disease resistant) at the National Pulses Research Centre, Tamil Nadu Agricultural University, Vamban, Tamil Nadu during July-September 2018 under Augmented Design in the field. Each line was sown in one row of 3 m in length with a spacing of 30 cm as between row and 10 cm as within row. Susceptible genotypes CO 5 and MDU 1 were sown as disease spreader rows after every eight rows and also around the plots. The MYMV disease score was recorded on 60 DAS, by using phenotype rating scale from 1 (resistant) to 9 (highly susceptible), as suggested by Singh et al. (1995). The mean of each progeny was calculated and used as phenotypic data. A total of 525 SSR primers were used to test polymorphism between parents MDU 1 and Mash 1008. Genotyping was carried out for 112 F2:3 RILs of the cross MDU 1 x Mash 1008 with 35 polymorphic SSR markers. Linkage and QTL analyses were performed using QTL IciMapping (version 4.1.0.0) (Wang et al. 2016) and QGene 4.4.0 (Joehanes and Nelson 2008) respectively. Two mapping populations MDU 1 x Mash 114 and CO 5 x VBN 6 in F2:3 and F2 generations respectively were used in this study to validate the identified QTL regions.Result: QTL study indicated the presence of two major QTLs for MYMV disease score in LG 2 and LG 10 at 60 DAS with 20.90 and 24.90% of phenotypic variation respectively. Validation of these QTLs in two other mapping population indicated that QTL on LG 10 was validated with high phenotypic variation of 45.40-46.00%. Hence it may conclude that qmymv10_60 may be utilized for MAS/MABC with assured improvement on MYMV disease resistance in blackgram.

VBN 11 - A new high yielding and MYMV disease resistant blackgram variety

Blackgram variety VBN 11 (VBG 12-062) was derived from PU 31 x CO 6. It matures in 70 – 75 days. VBN 11 has a yield potential of 899 kg/ha. It is 14.8 and 11.8 % increased yield over VBN 6 (783 kg/ha) and VBN 8 (804 kg/ha) respectively. This variety has determinate plant type, medium duration with synchronized maturity and resistance to Mungbean Yellow Mosaic Virus (MYMV) disease and moderate resistance to powdery mildew disease. It is recommended for Kharif, Rabi and Summer seasons of Tamil Nadu. It was released by State Variety Release Committee during 2020 with the variety designation blackgram VBN 11.

Development of Mapping Population and Validation of Molecular Markers Associated with MYMV Resistance in Mungbean

Background: Mungbean yellow mosaic virus disease is the most devastating disease on Mungbean production. The virus is transmitted by whitefly and can cause yield losses from 75 to 100 per cent. The development of mungbean cultivars resistant to both virus and its vector is considered as one of the most desirable means of managing the disease as it is environmentally safe and highly efficient. The selection of resistant genotypes in conventional methods is complex and time consuming. Hence, the use of molecular markers linked with resistance genes is powerful as it hastens the breeding programmes. The current study was aimed to develop mapping population and to validate molecular markers associated with Mungbean yellow mosaic virus (MYMV). Methods: The present investigation was carried out with 260 F2 individuals that were derived from crossing DGGV-2 and IPM 2-14 during Kharif-2017 at Main Agril Research Station, UAS, Dharwad. Hybrid seeds of this cross were harvested individually and sown during rabi 2017 along with the two parents, as checks for distinguishing the true hybrids. Hybridity of F1s was confirmed through molecular marker analysis and the true F1s were selfed to raise the F2 generation. Result: Of the 24 previously reported simple sequence repeat markers used for detecting the polymorphism, two markers viz., CEDG305 and CEDG115 were found to be polymorphic between DGGV-2 and IPM-2-14. Two hundred and sixty F2 plants segregated in the ratio of 3 S:1 R (202 susceptible: 58 resistant) as phenotypic and 1: 2 :1 as genotypic ratio implying that single recessive gene controlled resistance. Single marker analysis revealed that the molecular markers CEDG305 and CEDG115 were associated with MYMV resistance with a phenotypic variance of 24.5 and 10.3 per cent respectively.

Screening of mungbean germplasm against mungbean yellow mosaic virus under natural condition

Mungbean [Vigna radiata (L.) Wilczek] is an important legume which can be grown in all three crop seasons viz., kharif, rabi and spring/summer in India, as sole or inter crop for grain and green manure. The production of mungbean is severely affected by mungbean yellow mosaic virus (MYMV) caused by begmoviruses transmitted by white fly, Bemesia tabaci. The absence of resistant/tolerant sources against MYMV disease leads to tremendous crop yield losses, with the aim of identifying the resistant source we carried out an experiment at UAS Dharwad, screened one hundred seven genotypes of mungbean germplasm lines against MYMV during summer season under field conditions. The germplasm was categorized in to resistant and susceptible depending upon severity of disease. The differential response of mungbean accessions to MYMV was determined and most of the genotypes studied were categorized as susceptible to moderately susceptible. In spite of the variable response to MYMV, the genotypes HUM 1, KM 15, KM 16, KM 24, KM 28, KM30, KM 36, KM 39, KM45, KM 47, KM 49, KM 51, KM 60, KM70, KM78 and KM 79 exhibited resistant reaction against the MYMV disease fourteen were moderately resistant and 30 were moderately susceptible. Remaining 30 accessions were classified as susceptible and 43 as highly susceptible accessions.

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).