Yellow Mosaic Research Articles

Plant virology

The first infectious agent to bear the name 'virus' was described in 1898: a plant pathogen called tobacco mosaic virus that infects a wide range of plants and results in a yellow mosaic of the leaves. Since then, the study of plant viruses has facilitated new discoveries in both virology and plant biology. Traditionally, research has focused on viruses that cause severe disease in plants used for human and animal food or recreation. However, closer inspection of the plant-associated virome is now revealing interactions that range from pathogenic to symbiotic. Although they are often studied in isolation, plant viruses are usually found as part of a broader community that includes other plant-associated microbes and pests. For example, biological vectors of plant viruses (arthropods, nematodes, fungi, and protists) can facilitate the transmission of viruses between plants in an intricate interaction. To enhance transmission, viruses can induce the plant to 'lure' the vector by modulating plant chemistry and defenses. Once delivered to a new host, viruses are dependent on specific proteins that modify the structural components of the cell to enable transport of viral proteins and genomic material. Links between antiviral plant defenses and key steps in virus movement and transmission are being revealed. Upon infection, a suite of antiviral responses is triggered, including the expression of resistance genes - a favored strategy to control plant viruses. In this primer, we discuss these features and more, highlighting the exciting world of plant-virus interactions.

Impact of Large Scale Demonstration on Productivity and Profitability of Blackgram Under Rainfed Conditions of Chamarajanagara District, Karnataka (Zone-6)

Background: Blackgram is a major pulse crop grown next to horsegram and greengram in Chamarajanagar district. Unavailability of high yielding and yellow mosaic resistant varieties, poor agronomic and pest management practices has led to drastic fall down in productivity and profitability of blackgram in Chamarajanagara district. Methods: Large scale demonstration was conducted in an area of 60 ha covering 150 farmers of K. Mukahalli, Kotamballi, Devalapura, Doddatuppuru and Y.K. mole villages. Further the integrated crop management practices in blackgram variety LBG-791 was demonstrated during Pre-kharif of 2020-21, 2021-22 and 2022-23 by ICAR-Krishi Vigyan Kendra, Chamarajanagara, Karnataka. Result: The Yellow mosaic disease incidence was significantly less in LBG-791 (1.40%) when compared to T-9 (Farmers’ variety) (66.8%). Adoption of LBG-791 along with improved crop management practices resulted in 121.5% higher mean grain yield as compared to farmers practice. Higher Benefit: Cost ratio of 1.94 was recorded with integrated crop management practices as compared to farmers’ practices (1.03). The study exhibited mean extension and technology gap of 379 kg/ha and 119 kg/ha respectively. Further the mean technology index was 14.73 per cent. These results indicate that there is a great opportunity for farmers of Karnataka (Zone-6) for increasing productivity and profitability of the blackgram crop by adoption of Integrated Crop Management Practices (ICMP).

Complete genome sequence of a new virus from Allium sativum L in China

The complete genome of a new virus belonging to the family Betaflexiviridae was identified in garlic and sequenced by next-generation sequencing and reverse transcription PCR. The complete RNA genome (GenBank accession number OP021693) is 8191 nucleotides in length, excluding the 3' poly(A) tail, and contains five open reading frames (ORFs). These open reading frames encode the viral replicase, triple gene block, and coat protein, and the genome organization is typical of members of the subfamily Quinvirinae. The virus has been tentatively named "garlic yellow curl virus" (GYCV). Phylogenetic analysis suggested that it represents an independent evolutionary lineage in the subfamily, clustering with the currently unclassified garlic yellow mosaic associated virus (GYMaV) and peony betaflexivirus 1 (PeV1). Differences between the phylogenies inferred for the replicase and coat protein indicate that the new virus does not belong to any established genus of the family Betaflexiviridae. This is the first report of GYCV in China.

ADAPTIVE VALUE OF SOYBEAN VARIETIES GROWN IN DIFFERENT ECOGRADIENTS

The further expansion of soybean acreage and increase in productivity will be facilitated by the introduction of new modern varieties, which are determined by higher productivity potential and a higher level of resistance to the main fungal and bacterial diseases. However, soybean plants are affected by more than 50 diseases. It is known that pathogenic organisms lead to significant losses of the soybean crop (by 15-20%, and by epiphytotic development – by 50%).The results of studies on the assessment of soybean varieties for adaptability (ecological plasticity and stability) in different soil and climatic conditions for resistance to diseases (ascochitosis, yellow mosaic) are presented. Soybean varieties were ranked according to ecological plasticity and stability according to their response to environmental conditions. Our studies have shown that the intensity of the development of ascochitosis and yellow mosaic depends not only on the genetic characteristics of the genotypes, but also on factors related to the growing area, especially the hydrothermal and edaphic conditions of the region. The varieties Oriana – 93.4% and Hoverla – 93.2% stood out for their resistance to ascochitosis damage under different hydrothermal and edaphic conditions, which were characterized by a low reaction to a change in the hydrothermal growing regime, the coefficient of ecological plasticity (bi) < 1. That is, these varieties soybeans provided high indicators of resistance to ascochitosis despite a deficit or sufficient moisture supply in different ecogradient studies. The following varieties stood out for resistance to yellow mosaic: Hoverla – 85.0%, Oriana – 84.9%, Amethyst – 83.0. It should be noted that according to the parameters of ecological plasticity and stability (adaptability), the listed varieties belong to genotypes with a conservative reaction to changes in the agro-environment of cultivation, the coefficient of ecological plasticity (bi) < 1.

Impact assessment of natural variations in different weather factors on the incidence of whitefly, Bemisia tabaci Genn. and yellow vein mosaic disease in Abelmoschus esculentus (L.) Moench

Bemisia tabaci Gennadius, also renowned as the silver leaf whitefly, is among the most damaging polyphagous insect pests in many commercially important crops and commodities. A set of field experiments were conducted for three consecutive years i.e., 2018–2020, to investigate the role of variations in rainfall, temperature, and relative humidity on the abundance of B. tabaci in okra (Abelmoschus esculentus L. Moench). In the first experiment, the variety Arka Anamika was cultivated twice a year to analyse the incidence of B. tabaci concerning the prevailing weather factors and the overall pooled incidence recorded during the dry and wet season was 1.34 ± 0.51 to 20.03 ± 1.42 and 2.26 ± 1.08 to 18.3 ± 1.96, respectively. Similarly, it was observed that the highest number of B. tabaci catch (19.51 ± 1.64 whiteflies/3 leaves) was recorded in morning hours between 08:31 to 09:30 a.m. The Yellow Vein Mosaic Disease (YVMD) is a devastating disease of okra caused by begomovirus, for which B. tabaci acts as a vector. In another experiment, screening was conducted to check the relative susceptibility of three different varieties viz., ArkaAnamika, PusaSawani, and ParbhaniKranti against B. tabaci (incidence) and YVMD ((Percent Disease Incidence (PDI), Disease Severity Index (DSI), and Area Under the Disease Progress Curve (AUDPC)). The recorded data was normalized by standard transformation and subjected to ANOVA for population dynamics and PDI. Pearson's rank correlation matrix and Principal Component Analysis (PCA) have been used to relate the influences of various weather conditions on distribution and abundance. SPSS and R software were used to create the regression model for predicting the population of B. tabaci. Late sown PusaSawani evolved as a highly susceptible variety in terms of B. tabaci (24.83 ± 6.79 adults/3leaves; mean ± SE; N = 10) as well as YVMD i.e., PDI (38.00 ± 4.95 infected plants/50plants), DSI (71.6–96.4% at 30 DAS) and AUDPC (mean β-value = 0.76; R2 = 0.96) while early sown Parbhani Kranti least susceptible to both. However, the variety ArkaAnamika was observed as moderately susceptible to B. tabaci and its resultant disease. Moreover, environmental factors were predominantly responsible for regulating the population of insect pests in the field and hence its productivity like rainfall and relative humidity were negative while the temperature was positively correlated with B. tabaci (incidence) and YVMD (AUDPC). The findings are helpful for the farmers to choose need-based IPM strategies than timing-based, which would fit perfectly with the present agro-ecosystems in all ways.

Improved Spectral Detection of Nitrogen Deficiency and Yellow Mosaic Disease Stresses in Wheat Using a Soil Effect Removal Algorithm and Machine Learning

Wheat yellow mosaic disease is a low-temperature and soil-borne disease. Crop infection by the yellow mosaic virus can lead to severe yield and economic losses. It is easily confused with nitrogen deficiency based on the plant’s morphological characteristics. Timely disease detection and crop management in the field require the precise identification of crop stress types. However, the detection of crop stress is often underappreciated. Wheat nitrogen deficiency and yellow mosaic disease were investigated in the field and wheat physiological and biochemical experiments were conducted to collect agronomic indicators, four years of reflectance spectral data at green-up and jointing were collected, and then studies for the detection of nitrogen deficiency and yellow mosaic disease stresses were carried out. The continuous removal (CR), first-order derivative (FD), standard normal variate (SNV), and spectral separation of soil and vegetation (3SV) preprocessing methods and 96 spectral indices were evaluated. The threshold method and variance inflation factor (TVIF) were used as feature selection methods combined with machine learning to develop a crop stress detection method. The results show that the most sensitive wavelengths are found in the 725–1000 nm region, while the sensitivity of the spectrum in the 400–725 nm region is lower. The PRI670,570, B, and RARSa spectral indices can detect nitrogen deficiency and yellow leaf disease stress, and the OA and Kappa values are 93.87% and 0.873, respectively, for PRI670,570, which is the best index. A 3SV-TVIF-SVM stress detection method was then proposed, using OA and Kappa values of 96.97% and 0.931, respectively, for field data validation. The results of the study can provide technical support and a theoretical basis for the accurate control of yellow mosaic disease and nitrogen fertilizer management in the field.

COMPARATIVE ASSESSMENT OF VARIETY SAMPLES OF COMMON BEANS ACCORDING TO THE VARIABILITY OF VALUABLE ECONOMIC CHARACTERS

A comparative evaluation of the selection material was carried out and the best variety samples of common beans were selected, both in terms of the level of manifestation of signs, and their sustainable implementation under a contrasting hydrothermal growing regime during the period of research. The differences between the variety samples were established by means of a comparative assessment of the manifestation of signs compared to the standard. According to the height of attachment of the lower beans, the following cultivars stood out: UD0302930 - 16.4 cm, coefficient of variation (V, %) - 2.6%, coefficient of agronomic stability (As) - 97.4%, homeostaticity (Hom) - 6.3; UD0302957 – 16.1 cm, coefficient of variation (V, %) – 3.5%, coefficient of agronomic stability (As) – 96.5%, homeostaticity (Hom) – 4.6. The highest number of seeds per plant was noted in variety UD0301736 - 42.4 pcs., the coefficient of variation (V, %) - 6.2%, the coefficient of agronomic stability (As) - 93.8%, and the highest homeostaticity (Hom) among the presented varieties - 6.9. The highest mass of 1000 grains was noted in the sample UD0300227 – 230.1 g, however, this form has higher variability indicators compared to the standard. Coefficient of variation (V,%) – 11.2%, coefficient of agronomic stability (As) – 88.8%, homeostaticity (Hom) – 20.6; UD0303753 – 187.1 g, coefficient of variation (V, %) – 8.1%, coefficient of agronomic stability (As) – 91.9% and the highest homeostatic index (Hom) in our studies – 23.2. Compared to the standard, the best yield samples were: UD0300227 – 349 g, UD0301736 – 359 g, UD0300411 – 339 g, UD0301043 – 333 g, Local 1 – 333 g.The highest resistance to damage by virus and yellow virus mosaic was noted in varieties: UD0301736 – 83.0 and 79.9%, UD0300227 – 81.2 and 78.9%, UD0300411 – 77.0 and 78.1%. The following cultivars stood out for their resistance to bacterial blight and bacterial wilt: UD0301736 – 92.4 and 89.4%, UD0300227 – 92.3 and 88.5%, UD0300411 – 89.9 and 85.9%; Local 1 – 88.6 and 83.4%.

Deciphering the role of alternative splicing as modulators of defense response in the MYMIV- Vigna mungo pathosystem.

Alternative splicing (AS) is a crucial regulatory mechanism that impacts transcriptome and proteome complexity under stressful situations. Although its role in abiotic stresses is somewhat understood, our understanding of the mechanistic regulation of pre-mRNA splicing in plant-pathogen interaction is meagre. To comprehend this unexplored immune reprogramming mechanism, transcriptome profiles of Mungbean Yellow Mosaic India Virus (MYMIV)-resistant and susceptible Vigna mungo genotypes were analysed for AS genes that may underlie the resistance mechanism. Results revealed a repertoire of AS-isoforms accumulated during pathogenic infestation, with intron retention being the most common AS mechanism. Identification of 688 differential alternatively spliced (DAS) genes in the resistant host elucidates its robust antiviral response, whereas 322 DAS genes were identified in the susceptible host. Enrichment analyses confirmed DAS transcripts pertaining to stress, signalling, and immune system pathways have undergone maximal perturbations. Additionally, a strong regulation of the splicing factors has been observed both at transcriptional and post-transcriptional levels. qPCR validation of candidate DAS transcripts with induced expression upon MYMIV-infection demonstrated a competent immune response in the resistant background. The AS-impacted genes resulted either in partial/complete loss of functional domains or altered sensitivity to miRNA-mediated gene silencing. A complex regulatory module, miR7517-ATAF2, has been identified in an aberrantly spliced ATAF2 isoform that exposes an intronic miR7517 binding site, thereby suppressing the negative regulator to enhance defense reaction. The present study establishes AS as a non-canonical immune reprogramming mechanism that operates in parallel, thereby offering an alternative strategy for developing yellow mosaic-resistant V. mungo cultivars. This article is protected by copyright. All rights reserved.

Development of Specific Detection for Mungbean Yellow Mosaic India Virus Infecting Yard Long Bean in Java, Indonesia

Yellow mosaic disease was reported for the first time in Indonesia in 2008. Its infection on yard long bean caused significant yield loss. Mungbean yellow mosaic India virus (MYMIV), member of genus Begomovirus was identified as the main causal agent. Specific and accurate detection is important for disease monitoring as part of disease management strategy. The aim of this study was to construct specific primer pairs for quick and robust detection of MYMIV using polymerase chain reaction method. A pair of primers MY1/MY2 was designed in this study to amplify part of MYMIV coat protein. In silico and in vitro test showed that MY1/MY2 primers specifically amplified MYMIV.

Gene Effects of Quantitative Traits through Six Parameter Model of Generation Mean Analysis in Black Gram [Vigna mungo (L.) Hepper

Background: Yellow mosaic disease (YMD) caused by Mungbean Yellow Mosaic Virus (MYMV) is one of the most destructive biotic constraints for production in urdbean. Development and introduction of resistant cultivars with high seed yield is considered as the most economical and eco-friendly option to manage YMD, for which understanding the gene action controlling the inheritance of different traits along with YMD resistance is an important requirement. Methods: Material comprised of four diverse genotypes (TU 94-2, PU 31, IPU 94-1 and LBG 623), six F1s, six BC1s and six BC2s and six F2s. These six generations of all the six crosses were evaluated for various yield related traits in rabi, 2020-21 and phenotyped for YMD in summer, 2021 at Lam, Guntur, Andhra Pradesh which is hotspot for YMD. Result: Inadequacy of additive-dominant model for all most all traits including YMD except for test weight was observed. It was found that, [l] type of non-allelic interaction was observed to be predominant for majority of the traits. Further, the existence of duplicate type of epistasis in the inheritance was evident at least in few crosses for all the traits (except days to maturity). The duplicate epistasis will reduce the variation in F2 and subsequent generations, thereby hinder the pace of the progress through selection.

Infection of Ageratum yellow vein virus on Weed Crassocephalum crepidioides in Bengkulu

Infection of Ageratum yellow vein virus on Weed Crassocephalum crepidioides in Bengkulu Weeds with symptoms of virus infection were found on three cultivation areas of papaya (Carica papaya) in Bengkulu province, Indonesia. Symptoms on weeds involved yellowing of lamina and vein, yellow mosaic, and leaf curling. This study aimed to identify and detect Begomovirus on weed species, Crassocephalum crepidioides. Virus detection was conducted by polymerase chain reaction method using a pair of universal primers for Begomovirus (SPG1/SPG2). A DNA fragment of 912 bp in size was successfully amplified from C. crepidioides with leaf curl symptom. Analysis using Blastn showed that Begomovirus sample from C. crepidioides has the closest relationship with Ageratum yellow vein virus (AYVV) isolate from Taiwan (DQ866134.1) with nucleotide homology of 99%. This is the first report of AYVV infection in C. crepidioides in Indonesia.

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.

In Vivo Antiphytoviral and Aphid Repellency Activity of Essential Oils and Hydrosols from Mentha suaveolens and Foeniculum vulgare to Control Zucchini Yellow Mosaic Virus and Its Vector Aphis gossypii.

In recent years, natural compounds have gained attention in many fields due to their wide-range biological activity. In particular, essential oils and their associated hydrosols are being screened to control plant pests, exerting antiviral, antimycotic and antiparasitic actions. They are more quickly and cheaply produced and are generally considered safer for the environment and non-target organisms than conventional pesticides. In this study, we report the evaluation of the biological activity of two essential oils and their corresponding hydrosols obtained from Mentha suaveolens and Foeniculum vulgare in the control of zucchini yellow mosaic virus and its vector, Aphis gossypii, in Cucurbita pepo plants. The control of the virus was ascertained with treatments applied either concurrently with or after virus infection; choice tests were performed to verify repellency activity against the aphid vector. The results indicated that treatments could decrease virus titer as measured using real-time RT-PCR, while the experiments on the vector showed that the compounds effectively repelled aphids. The extracts were also chemically characterized using gas chromatography-mass spectrometry. Mentha suaveolens and Foeniculum vulgare hydrosol extracts mainly comprised fenchone and decanenitrile, respectively, while essential oils analysis returned a more complex composition, as expected.

Screening of Mung Bean Genotypes against Yellow Mosaic Virus (YMV) Resistance

Experiment was conducted to identify the resistant Mung bean varieties against MYMV in Kharif during 2017. Ten Indian mung bean genotypes obtained from AICRP on Arid legumes, RARI, Durgapura, Jaipur, were used in the screening experiment and the obtained results revealed that there was significant variation among the genotypes for resistance against MYMV. Based on the average MYMV score, only two genotypes (IPM 02-3 and IPM 0205-7) were found completely free from the disease and the plants had maximum chlorophyll content whereas IPM-409-4 and RMG 991 were found resistant and chlorophyll content was low as compared to the highly resistant genotypes. The rest of six genotypes observed moderately resistant, moderately susceptible, susceptible and highly susceptible to the disease.

Screening of Rajmash Varieties against Major Insect Pest

Among seven varieties screened, Amber was found resistant to Thrips and Bean Cowpea Yellow Mosaic Virus and tolerant to cold with yield of 13.66 q/ha, followed by Utkarsh susceptible to all sucking insect pest, but found tolerant to BCMV and Cold with yield of 11.58 q/ha. Uday (Bold seeded) variety was at par with Utkarsh with yield of 11.22 q/ha, but susceptible to sucking insect pest, BCMV and cold. Moderate yields were recorded in Arun (6.96 q/ha) which is also found susceptible to all sucking pests, Arka Komal (6.14 q/ha) and Chintapalle Red (5.62 q/ha). Phalguna recorded minimum yield (2.08 q/ha), as it was found susceptible to Whitefly and Thrips.

Detecting Tomato Leaf Curl New Delhi Virus Causing Ridge Gourd Yellow Mosaic Disease, and Other Begomoviruses by Antibody-Based Methods.

The incidence and severity of begomovirus diseases have been increasing around the world recently, and the ridge gourd [Luffa acutangula (Roxb.) L.] is the latest example of a crop that has become highly susceptible to the outbreak of the tomato leaf curl New Delhi virus (ToLCNDV, genus Begomovirus) in India. Accurate diagnosis of causal agents is important in designing disease management strategies. In this study the coat protein (CP) gene from a ToLCNDV-Rg ridge gourd isolate was used to produce polyclonal antibodies (ToLCNDV-Rg-CP-PAb) in a rabbit. The antibodies successfully detected a 30.5 kDa ToLCNDV-Rg-CP in extracts of symptomatic ridge gourd leaf samples by several assays, such as Western Blotting (WB), Dot Immuno Binding Assay (DIBA), Direct Antigen Coating Enzyme Linked Immuno Sorbent Assay (DAC-ELISA), Immuno Capture Polymerase Chain Reaction (IC-PCR), and Immuno Capture Loop-Mediated Isothermal Amplification (IC-LAMP) assays. However, none of the negative samples tested positive in either of the detection methods. Among all the methods tested, the immunocapture assay, IC-LAMP, was the most sensitive in detecting ToLCNDV-Rg. Furthermore, antibodies generated in this study also detected other commonly occurring begomoviruses in South India, such as tomato leaf curl Palampur virus and squash leaf curl China virus in cucurbits. Together, ToLCNDV-Rg-CP-PAb can be used for detecting at least three species of begomoviruses infecting cucurbits. The obtained antibodies will contribute to monitoring disease outbreaks in multiple crops.

Development of improved genotypes for extra early maturity, higher yield and Mungbean Yellow Mosaic India Virus (MYMIV) resistance in soybean (Glycine max)

Context Breeding for early maturity and higher yield is the principal objective in genetic improvement of Indian soybean. Yellow Mosaic Disease caused by Mungbean Yellow Mosaic India Virus (MYMIV) causes 80% yield loss in soybean. Aims This study aimed to develop early maturing, MYMIV resistant and high yielding soybean genotypes for enhancing soybean production and expanding the land area under cropping. Methods MYMIV resistance was introgressed from G. soja in to a widely adaptable cultivar JS 335 through a series of four generations of backcrosses and by evaluating derived progeny against MYMIV at a disease hot spot. Key results An extra-early maturing (71 days) genetic stock called NRC 252 was developed, which can be a potential gene donor in breeding for early maturing soybean varieties. Introgression lines YMV 1, YMV 2, YMV 11 and YMV 16 with MYMIV resistance and higher yield performance over recurrent parent and other check varieties were identified and characterised. Biplot analysis, assessing the main effect of genotype and the interaction of genotype with environment, revealed an ideal genotype with respect to 100-seed weight and grain yield that was also promising under sugarcane-soybean intercropping system in spring season. Conclusions Alleles from wild type soybean could improve yield attributing traits and MYMIV resistance in cultivated soybean. Improved genotypes such as YMV 1, YMV 2, YMV 11 and YMV 16 were found superior to the recurrent parent JS 335 as well as other check varieties. Implications The genotypes developed in the present study will help in reducing the damage caused by MYMIV disease and expansion of the area of soybean cultivation through intercropping with sugarcane.

Detection and Classification of Yellow Mosaic Disease in Vigna mungo using Convolutional Neural Network Deep Learning Models

The yield of the black gram crop is negatively impacted by Yellow Mosaic Disease (YMD). Both quantity and quality of the black gram suffer significantly from this disease. Accurate diagnosis, flawless identification, and early detection guide the grower for proper and timely management of the disease. Deep learningbased pre-trained models have revolutionized the classification and identification of plant leaf disease in recent times. In the present study yellow mosaic disease of black gram has been classified using four deep learning models namely; DarkNet-19, SqueezeNet, AlexNet, and GoogLeNet. A total of 1100 images were collected from field experiments for each of three classes namely healthy, moderate and susceptible plants. During the field investigation, datasets with images of three classes; healthy, moderate, and susceptible were collected, pre-processed, and augmented to create a set of 1100 images of each class. Seventy percent of the images were used for the training of the models and thirty percent of the images were used for validation. The results obtained for different deep learning architectures DarkNet-19, SqueezeNet, AlexNet, and GoogLeNet showed validation accuracy and loss scores of 96.09, 60.74, 94.41, and 93.85%, and 0.2319, 0.6923, 0.2429 and 0.1399, respectively. For the YMD classification in blackgram, DarkNet-19 showed the highest accuracy and SqueezeNet showed the lowest accuracy.

Morphological Screening of Black Gram Genotypes with Reference to Mung Bean Yellow Mosaic Virus

One of the most devastating diseases affecting blackgram productivity in India is mung bean yellow mosaic. It is transmitted by whitefly (Bemisia tabaci). The current investigation was carried out to identify the blackgram genotypes resistant against the Mung bean yellow Mosaic virus (MYMV) through field screening at natural condition. The genotypes were screened using the infector row method. Twelve blackgram genotypes namely VBN-2, VBN-3, VBN-5, VBN-6, VBN-7 VBN-8, VBN-9 VBN-10, VBN-11, ADT-5, ADT-6 and CO-5 were used for screening during summer 2022. The genotypes viz., VBN-6, VBN-10 and VBN-11 were found to be resistant and moderately resistant viz., VBN-4, VBN-5, VBN-7, and VBN-8. It implies that utilization of these genotypes as YMV resistance donors for results in the production of high yielding MYMV resistant varieties through backcrossing or marker assisted backcrossing by introgression of the genes to agronomically potential genotypes that were susceptible to MYMV.

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.