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Introduction: Banded sheath blight (Bsb) disease, caused by Rhizoctonia solani , is an emerging problem in barnyard millet cultivation. One of the significant goals of pathogenomic research is to identify genes responsible for pathogenicity in the fungus. Methods: A virulence profiling-based approach was employed and six R. solani isolates were collected from various ecological zones of India. The morphological parameters and virulence of all of the six R. solani isolates were investigated. The most virulent strain was designated as RAP2 and its genome has been sequenced, assembled, and annotated. Results: The RAP2 genome is 43.63 megabases in size and comprises 10.95% repetitive DNA, within which 46% are retroelements, 8% are DNA transposons, and 46% are unidentified DNA. The Gene Ontology (GO) annotation of RAP2 proteins revealed that "phosphorylation", "membrane", and "ATP binding" have the highest gene enrichment in the "biological process", "cellular component" and "molecular function" domains, respectively. The genome comprises a majority of secretory proteins in the pectin lyase fold/virulence factor superfamily, which break down plant cell wall polymers to extract saccharides. The RAP2 genome is comparable to R. solani , which infects maize and rice, but it diverges further from soybean in terms of nucleotide-level genetic similarity. Orthologous clustering of RAP2 protein sequences with R. solani infecting maize, rice, and soybean yields 5606 proteins shared across all genomes. GO analysis of 25 proteins specific to the RAP2 genome found enrichment in the ethylene response, which can cause spore germination and infection in host plants. Discussion: Interestingly, a 28-bp deletion in the RAP2 strain's cutinase domain was discovered in the cutinase protein, which might be important in the infection process, perhaps rendering the enzyme inactive or allowing the pathogen to infect barnyard millet while avoiding host defense. This study sheds light on the genetic makeup of R. solani , allowing researchers to discover critical genes related with pathogenicity as well as potential targets for fungicide development. [ABSTRACT FROM AUTHOR]

Blast disease causes significant damage to millets (pearl millet, finger millet and foxtail millet) and rice in India. This study investigates strains of Pyricularia, the causal agent of blast disease, in rice and millets in India in terms of their diversity, host preferences and phylogeny. One hundred and thirty‐six Pyricularia isolates causing rice and millet blast were collected from 46 locations in India. They displayed morphological diversity irrespective of host or location. All Pyricularia isolates were separated into two major clusters by a multilocus sequence‐based phylogenetic tree, which also demonstrated that most isolates are grouped according to their host associations. In contrast, a few finger millet isolates were found to be grouped with foxtail millet isolates. We explored how Pyricularia isolates behaved when exposed to rice and millets. Finger millet isolates were shown to be pathogenic on a wide variety of millets, whereas rice isolates were only found to infect rice and wheat. The majority of the blast isolates of millets were shown to be pathogenic on common weed species of the millet ecosystem, such as Echinochloa crusgalli, Eleusina indica and Erogrotis gagantica. Our findings emphasize the importance of pathogen surveillance in both cultivated crops and weed hosts, as well as the possible risk of blast fungus infection in Indian millets due to host expansion. Blast disease control programmes in India will be greatly enhanced by the knowledge gained in this study on the diversity and host association of Pyricularia strains. [ABSTRACT FROM AUTHOR]

Grapes (Vitis vinifera L.) is a popular horticultural crop which is vulnerable to a variety of infections during pre and post-harvest conditions. Presently management of these diseases is by the application of synthetic fungicides but non-chemical control methods have gained importance recently in reducing the postharvest decay. Among the epiphytic microflora (29 bacterial and 2 yeast) isolated from phylloplane and fructoplane of the grapes, screened for their antagonistic activity in vitro against grapes postharvest pathogens viz., Penicillium citrinum, Alternaria alternata and Colletotrichum gloeosporioides, 15 bacterial and 2 yeast isolates inhibited the growth of all three tested pathogens. These antagonists were found effective and can be utilized for the management of post-harvest diseases of grapes. [ABSTRACT FROM AUTHOR]

New Proso millet variety GPUP 28 was developed at Project Coordinating unit, ICAR-AICRP on Small Millets, University of Agricultural Sciences, GKVK, Bengaluru for cultivation in Zone 5 and 6 of Karnataka. It has been evolved through hybridization between two released varieties GPUP 8 and K1. This variety has desirable characteristics of both the parents. This new variety matures in 80-85 days. It has intermediate compact with globose-elliptic shaped inflorescence. Grain is oval shaped with golden yellow colour possesses higher test weight. This variety is moderately resistant to leaf blight and resistant to brown spot diseases. GPUP 28 contains more grain calcium (127.7 ppm) content compared to the check GPUP 21. This variety has iron content of 28.8 ppm, 11.6 per cent protein, and 24.2 ppm of Zinc. Fodder contains high crude fiber (39.91 %) and crude fat (0.62 %) content. New variety GPUP 28 recorded an average grain yield of 29.43 q/ha in station trials, 27.8 q/ha in multilocation trials and 12.76 q/ha in farm trials with mean grain yield of 23.33 q/ha. Across all the trials GPUP 28 registered an average yield of 23.33 q/ha with 20.84 per cent increased yield over check variety GPUP 21. In All India Co-ordinated trials, GPUP 28 yielded 1643 kg/ha across the locations. GPUP 28 ranked 2nd and recorded 13.38 per cent increased seed yield over the check GPUP 21 in AICRP trials. This new variety is recommended for release in annual plant scientists group meeting held at UAS, GKVK, Bengaluru on 1-3rd March 2021, Annual ZREP workshop of Zone-6 held on 5th April 2021, Annual ZREP workshop of Zone-5 held on 8th April 2021 and State varietal evaluation committee (SVEC) meeting held on 13th to 16th December 2021. NBPGR, New Delhi has issued national identity number IC 635735 for this variety. Because of its superior performance in Zone 5 and 6 of Karnataka this variety has been recommended for cultivation in Southern (Zone 6) and Eastern (Zone 5) Dry Zones of Karnataka state. [ABSTRACT FROM AUTHOR]

Little millet (Panicum sumatrense Roth ex Roem. and Schult.) is one of the hardiest minor cereal crop indigenous to Indian sub-continent. The crop is cultivated by tribal and poor farmers for food and feed. Leaf blight disease has been a major production constraint and fungicidal sprays for the management of the disease may not be economically viable and feasible. Hence, the present in vitro study was carried out to know the antifungal activity of six fungal and 10 bacterial bio-agents against Alternaria alternata inciting little millet leaf blight disease. Among the fungal bio-agents, Trichoderma harzianum (ThB5) and among the bacterial bio-agents, Bacillus velezensis (P42) showed mycelial growth inhibition of 75.18 and 84.75%, respectively. [ABSTRACT FROM AUTHOR]

Maximum percentdisease incidence (45.16%) was noticed in Besigeger village of Bellary district. In Koppal districts, maximum per cent disease incidence was recorded in Jerkundi (43.58%) followed by Koppal (41.07%). While lowest disease incidence was observed in Kalakbandi (21.87%). In Bagalkot district, maximum per cent disease incidence was recorded in Hebbal (31.41%) followed by Mahalingpur (22.42%). In Gadag district, maximum per cent disease incidence was recorded in Chumnal (36.42%). While lowest disease incidence was observed in Unchgere (25.70%). In Bijapur district, maximum disease incidence was observed in Babaleshwara (31.14%).Similarly, maximum disease incidence was observed in Appledinni (22.30%) followed by Tuntapur (18.75%) in Raichur district. Among different districts the Bellary district recorded maximum disease incidence (32.46%) followed by Koppal district (32.13%). While lowest incidence was observed in Raichur district (16.70%). Further Shot hole borer (Xyleborus fernicatus) association was noticed in the entire district, but it was absent in Raichure district. Higher wilt disease incidence was noticed in more than above 4-5 years orchards and while it was less in belove 3 years orchards. Shot hole bore association was noticed in more than 4-5 years. It was evident from the survey that among the commonly growing pomegranate cultivars, viz.,Bhagwa, Kesar, Ganesh, Arkta and Sindhur; the cultivar Bhagwa was found to be highly susceptible to C. fimbriata and shot hole borer. [ABSTRACT FROM AUTHOR]

Disease complexes involving nematode and fungi have gained momentum in the recent years. There was no conspicuous gall production in nematode alone and in combination with fungi. The affected roots showing brownish discolouration were observed in fungal spore suspension, fungal giant culture and fungal giant culture + M. incognita and M. incognita alone treatments. In uninoculated treatment there was no brownish discolouration. The two pathogens (M. incognita, C. fimbriata) adversely affected plant growth parameters like shoot and root length, fresh and dry weight of shoot, fresh and dry weight of root per plant. Among the two pathogens inoculated individually, maximum reduction in plant growth parameters noticed in fungal giant culture (C. fimbriata) treatment over control compared to fungal spore suspension, or M. incognita. Reduction in plant growth parameters caused by fungal spore suspension were noticed which is on par with M. incognita. With respect to of combined inoculations with nematode and fungi, greatest reduction in growth parameters was noticed in M. incognita + C. fimbriata. However, the treatment receiving the inoculum both pathogens, showed a highest reduction in plant growth parameters in comparison with other treatments. [ABSTRACT FROM AUTHOR]

In this experiment 45th day was crucial day for wilting. Branches were rapidly wilted in all treatment. After 45th day gradual yellowing and wilting was noticed very slowly due to effect of chemicals, bio agents and plant product, micronutrientand insecticide. Among the chemicals propiconazole was more effective followed by Difenoconazole. However in bio agents T. harzianumand P. fluorescens were effective than alone.Before drenching all plants showing partial wilting and yellowing but none of the plants completely wilted in all treatments. Propiconazole was significantly superior than remaining treatments. Propiconazole treated plants were recovered at 105th day, followed by difenconazole the plants were recovered at 120th day. These two chemicals were effective than remaining treatments. After 120th day propiconazole (0.00%), difenconazole (0.00%) and T. harzianum + P. flourescence (0.00%) are on par with each other. captan+ carbendazim (16.66%), T. harzianum (16.66%), Copper oxychloride (16.66%) and mancozeb (16.66%) were on par with each other. Followed by neemcake (33.34%) and vitavax power (33.34%). In control (83.33%) was showing highest percent of wilting. [ABSTRACT FROM AUTHOR]

In this experiment 45th day was crucial day for wilting. Branches were rapidly wilted in all treatment. After 45th day gradual yellowing and wilting was noticed very slowly due to effect of chemicals, bio agents and plant product, micronutrient insecticide. Among the chemicals propiconazole was more effective followed by Difenoconazole. However in bio agents T. harzianumand P. fluorescens were effective than alone. The propiconazole and difenconazole was significantly superior than remaining treatments after 120th day propiconazole (0.00%), difenconazole (0.00%) and T. harzianum + P. flourescence (0.00%) are on par with each other. The percent survival of plants in captan+ carbendazim (83.34%), T. harzianum (83.34%), Copper oxy chloride (83.34%) and mancozeb (83.34%) were on par with each other. Followed by neemcake (66.66%) and vitavax power (66.66%). In control (83.33%) totally showing least percent of survival of plants. [ABSTRACT FROM AUTHOR]

Dypsis lutescens, commonly known as areca palm, is a highly valued ornamental species due to its aesthetic value. However, the foliage is vulnerable to various pathogens, particularly those responsible for fungal leaf spot diseases. In October 2023, a severe incidence (93 %) of destructive leaf spots was recorded on Dypsis lutescens at the University of Agricultural Sciences, GKVK, Bangalore, and surrounding areas. The leaf spot symptoms manifested as frog-eye-like lesions, leading to complete leaf desiccation and significantly reducing the palms ornamental value. The pathogen exhibited the highest radial growth (90.00 mm) and prominent sporulation on oat meal agar, whereas Richard's synthetic agar resulted in the lowest radial growth (38.00 mm) with no sporulation. Morphological and multilocus phylogenetic analyses confirmed the pathogen as Bipolaris heliconiae. Pathogenicity tests fulfilled Koch's postulates, confirming that Bipolaris heliconiae is the causative agent of leaf spot disease in Dypsis lutescens in India. This novel finding underscores the emergence of a new disease and highlights the urgent need for effective management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this research paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Little millet (LM) is a minor cereal crop grown in the Indian sub-continent. During October 2018, dark brown, circular to oval necrotic spots surrounded by concentric rings were observed on the upper leaf surface of the LM (cv. VS-13) grown in the fields of the University of Agricultural Sciences, Bengaluru, India (13.0784oN, 77.5793oE). As the disease progressed, infected leaves became blighted. Disease incidence up to 53% was recorded in 3 fields of 0.4-hectare area each. Thirty symptomatic leaves were collected to isolate the associated causal organism. The margins of diseased tissue were cut into 5 × 5-mm pieces, surface-sterilized in 75% ethanol for 45 seconds followed by 1% sodium hypochlorite for 1 min, finally rinsed in sterile distilled water five times and placed on PDA. After 7 days of incubation at 25°C, greyish fungal colonies appeared on PDA. Single-spore isolations were performed to obtain ten isolates. Pure cultures of the fungus initially produced light gray aerial mycelia that later turned to dark grey. All isolates formed obclavate to pyriform conidia measured 22.66-48.97μm long and 6.55-13.79µm wide with 1-3 longitudinal and 2-7 transverse septa with a short beak (2.55-13.26µm) (n=50). Based on the conidial morphology, the fungus was identified as Alternaria sp. Further, the taxonomic identity of all ten isolates was confirmed as A. alternata using species-specific primers (AAF2/AAR3, Konstantinova et al. 2002) in a PCR assay. Later, one of the isolate UASB1 was selected, and its internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (gapdh), major allergen Alt a 1 (Alt a 1), major endo-polygalacturonase (endoPG), OPA10-2, and KOG1058 genes were amplified in PCR (White et al. 1990; Berbee et al. 1999; Woudenberg et al. 2015), and the resultant products were sequenced and deposited in the NCBI GenBank (ITS, MN919390; gapdh, MT637185; Alt a 1, MT882339; endoPG, MT882340; OPA10-2, MT882341; KOG1058, MT882342). Blastn analysis of ITS, gapdh, Alt a 1, endoPG, OPA10-2, KOG1058 gene sequences showed 99.62% (with AF347031), 97.36% (with AY278808), 99.58% (with AY563301), 99.10% (with JQ811978), 99.05% (with KP124632) and 99.23% (with KP125233) respectively, identity with reference strain CBS916.96 of A. alternata, confirming UASB1 isolate to be A. alternata. For pathogenicity assay, conidial suspension of UASB1 isolate was spray inoculated to ten healthy LM (cv. VS-13) plants (45 days old) maintained under protected conditions. The spore suspension was sprayed until runoff on healthy leaves, and ten healthy plants sprayed with sterile water served as controls. Later, all inoculated and control plants were covered with transparent polyethylene bags and were maintained in a greenhouse at 28±2 ◦C and 90% RH. The pathogenicity test was repeated three times. After 8 days post-inoculation, inoculated plants showed leaf blight symptoms as observed in the field, whereas no disease symptoms were observed on non-inoculated plants. Re-isolations were performed from inoculated plants, and the re-isolated pathogen was confirmed as A. alternata based on morphological and PCR assay (Konstantinova et al. 2002). No pathogens were isolated from control plants. There is an increasing acreage of LM crop in India, and this first report indicates the need for further studies on leaf blight management and the disease impacts on crop yields.