MANAGEMENT OF TEA (CAMELLIA SINENSIS) DISEASES WITH APPLICATION OF MICROBES: A REVIEW

Tea (Camellia spp.) is one of the most economically important plantation crops and the second-largest non-alcoholic beverage in the world next to water being consumed by people in different forms. It is cultivated mainly in Assam, West Bengal covering the regions such as Darjeeling, Dooars, Terai, and South India in about 6.36 lakh hectares with a production of about 1338 million Kg made teas. Darjeeling tea is world famous for its specific aroma and flavor whereas Assam is known for premier CTC teas. Among various challenges encountered on its bountiful production and desired quality, the occurrence of numerous diseases is one of the major factors. Different fungal and one algal genus are considered as the major phytopathogens to cause leaf, stem, and root diseases. Blight (blister, gray, and brown), dieback, charcoal stem rot, root rot (brown and violet), and black rot are the major threat to tea sustainability. These diseases can be managed through the timely adoption of good agricultural practices. For the past couple of decades, due to the increased awareness about the adverse effects of synthetic fungicides usage, people have been looking for ideal alternative strategies to take care of tea diseases in India under the organic production system. Microbes such as genus Trichoderma, Bacillus, Pseudomonas, and Actinomycetes are capable of providing a protective umbrella to this crop against different diseases

Pure epitheliod perivascular epitheloid cell tumor (epitheliod angiomyolipoma) of kidney: Case report and literature review

Malignant kidney tumors are rare neoplasms accounting for 3% of adult malignancies. Majority of these arises in the renal parenchyma and are adenocarcinomas. Malignant mesenchymal tumors of kidney are extremely rare. We report on the clinical behavior, the radiological and histopathological details of one such case of malignant mesenchymal tumor, we encountered

H yposidra talaca NPV (HytaNPV): a potential baculovirus for efficient control of the black inch worm, Hyposidra talaca Walker (Lepidoptera: Geometridae), a major pest of tea Camellia sinensis (Ericales: Theaceae (L.) O. Kuntze)

Abstract Background The black inch worm (BIW), Hyposidra talaca Walker (Lepidoptera: Geometridae), is a pest that defoliates tea leaves in India, posing a significant threat to the tea industry. Nucleopolyhedrovirus (NPV) is capable of infecting larvae of this species, which has raised the possibility of its use as a biocontrol agent. Results Rearing larvae in a semi-synthetic artificial diet produced healthy adults, which is sufficient for mass culture of H. talaca to support one of the IPM components using baculovirus. In artificial diets, the NPV was evaluated for its insecticidal activity against H. talaca. The bioassay findings of inoculated H. talaca nucleopolyhedrovirus virus (HytaNPV) at various concentrations showed that it was effective in killing the BIW. Purified polyhedral inclusion bodies (PIBs) were estimated to a concentration of 1 × 1010 PIBs per ml by mixing with water, and various concentrations of 0.25, 0.5, 1, 2, 5, 7.5, 10 ml/l were evaluated against BIW. Both laboratory and field studies revealed that HytaNPV is an eco-friendly and ecologically safe agent for controlling BIW. Besides no residue was estimated in made tea after the seventh day of exposure, and it is nontoxic to non-target species. Conclusion It was found that NPV is environmentally beneficial for the control of pests on tea plants and in production of pesticide-free tea. Tea ecosystems can reduce their reliance on conventional insecticides by using HytaNPV as an alternative bio-insecticide

Insect Microbial Symbionts: Ecology, Interactions, and Biological Significance

The guts of insect pests are typical habitats for microbial colonization and the presence of bacterial species inside the gut confers several potential advantages to the insects. These gut bacteria are located symbiotically inside the digestive tracts of insects and help in food digestion, phytotoxin breakdown, and pesticide detoxification. Different shapes and chemical assets of insect gastrointestinal tracts have a significant impact on the structure and makeup of the microbial population. The number of microbial communities inside the gastrointestinal system differs owing to the varying shape and chemical composition of digestive tracts. Due to their short generation times and rapid evolutionary rates, insect gut bacteria can develop numerous metabolic pathways and can adapt to diverse ecological niches. In addition, despite hindering insecticide management programs, they still have several biotechnological uses, including industrial, clinical, and environmental uses. This review discusses the prevalent bacterial species associated with insect guts, their mode of symbiotic interaction, their role in insecticide resistance, and various other biological significance, along with knowledge gaps and future perspectives. The practical consequences of the gut microbiome and its interaction with the insect host may lead to encountering the mechanisms behind the evolution of pesticide resistance in insects

Functional traits and phylogenetic analysis of top-soil inhabiting rhizobacteria associated with tea rhizospheres in North Bengal, India

Rhizobacteria associated with cultivated crops are known to stimulate plant growth through various indirect or direct mechanisms. In recent years, the host list of plant growth promotion/promoting rhizobacteria has expanded to include bean, barley, cotton, maize, rice, vegetables, peanut, rice, wheat, and several plantation crops. However, interaction of rhizobacteria with tea plants of organic and conventional tea gardens is poorly understood. In the present study, rhizobacterial species associated with tea rhizosphere were isolated from 14 tea gardens located in North Bengal, India. In total, 16 rhizobacterial isolates isolated from collected soil samples were assessed for antagonistic and plant growth promotion/promoting activity under laboratory conditions. Molecular characterization based on sequencing of 16S rRNA gene revealed dominance of Bacillus with five species followed by Pseudomonas with two species. Interestingly, only one isolate was affiliated with actinobacteria, i.e., Microbacterium barkeri. Out of 16 isolates, isolates Bacillus subtilis OKAKP01, B. subtilis BNLG01, B. paramycoides BOK01, M. barkeri BPATH02, and Stenotrophomonas maltophilia BSEY01 showed highest growth inhibition against Fusarium solani (68.2 to 72.8%), Pseudopestalotiopsis theae (71.1 to 85.6%), and Exobasidium vexans (67.4 to 78.3%) causing respective Fusarium dieback, gray blight, and blister blight diseases in tea crop. Further, these five isolates also possessed significantly greater antifungal (siderophore producer, protease, chitinase, and cellulase activity) and plant growth promotion/promoting (indole-3-acetic acid production, ACC deaminase, ammonia, and phosphate solubilization) traits over other eleven rhizobacterial isolates. Therefore, these five isolates of rhizobacteria were chosen for their plant growth promotion/promoting activity on tea plants in nursery conditions. Results from nursery experiments revealed that these five rhizobacteria significantly improved growth rates of tea plants compared with the control. Therefore, this study suggests that these rhizobacteria could be used to formulate biopesticides and biofertilizers, which could be applied to sustainable tea cultivation to improve crop health and reduce disease attack

Enhancement of the reproductive potential of Mallada boninensis Okamoto (Neuroptera: Chrysopidae), a predator of red spider mite infesting tea: An evaluation of artificial diets

Green lacewing Mallada boninensis is an important predator of various soft-bodied arthropods, including red spider mites in tea. Efforts were made to develop mass rearing technology for this predator in a cost effective manner. Three combinations of artificial diets (Protinex (AD1), egg yolk (AD2) and royal jelly (AD3) based) were evaluated in comparison with standard diet (Protinex + Honey). All the tested diets influenced the egg-laying capacity of M. boninensis. The egg yolk-based diet resulted in more egg production than the other two diets. Survival of all life stages of M. boninensis was also observed on each diet and no significant difference was noticed. Results revealed that the egg yolk-based diet is the best of the three diet combinations tested in view of high fecundity and survival rate of M. boninensis