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Lichens are symbiotic organisms that are composed of fungal partners and photosynthetic algal partners. During the symbiotic process in lichen thallus, the fungus synthesizes certain secondary metabolites in which lecanoric acid is very important in terms of antibiotic properties. Considering the vital importance of lecanoric acid, the present study aimed to produce lecanoric acid from the thallus of Parmotrema austrosinense lichen using Modified Bold's basal salt medium and evaluate the bio-efficacy against tea fungal pathogens. Lecanoric acid was purified and confirmed by micro-crystallization method and subsequently bioassayed against tea fungal pathogens. The results revealed that lecanoric acid registered a significant antifungal activity in terms of the growth inhibition of test pathogens. Companion systemic and botanical fungicides were found to be inferior to lecanoric acid in the percentage of growth inhibition. The inhibition rate varied among tea pathogens. Of the tea pathogens tested, tea leaf disease-causing pathogens including Cercospora theae (C. theae), Glomerella cingulata (G. cingulate), and Phomopsis theae (P. theae) showed the highest percentage of growth inhibition followed by stem and root rot diseases. The present study suggests that lecanoric acid showed an inhibitory effect against tea pathogens, which might be due to antibiotic properties and fungicidal action of lecanoric acid. [ABSTRACT FROM AUTHOR]

Tea is an important beverage with several health benefits to human beings, but increase in tea diseases is of much concern in recent days. Amongst several stem and root diseases of tea plants, Poria hypolateritia causing red root-rot and Phomopsis theae causing Phomopsis canker diseases are very important in terms of heavy crop loss in young as well as mature tea plantations, respectively. In the present study, indigenous biocontrol agents such as bacteria, fungi and actinomycetes were isolated from southern Indian tea soils collected from different agroclimatic regions and subjected to biosynthesis of copper and silica nanoparticles. Copper and silica nanoparticles were produced using selected indigenous biocontrol agents such as Pseudomonas fluorescens, Trichoderma atroviride and Streptomyces griseus and then characterise for their nature, size, shape, elemental analysis, distribution and functional groups. The results showed that copper and silica nanoparticles were inhibited the growth of P. hypolateritia and P. theae. Nanocopper and nanosilica were subjected to prepare various nanoformulations using suitable inert and eco-friendly carrier materials. Toxicity of nanoformulations was done using zebrafish model. It was confirmed that there was no toxicity of nanocopper and nanosilica when exposed to 0.5, 3 and 30 µg concentrations in terms of viability percentage of embryo, hatching rate, body mass index and heartbeat counts. The present investigation could be a novel approach for the management of root and stem diseases in tea plantations which in turn useful to enhance tea quality parameters. [ABSTRACT FROM AUTHOR]

The efficacy of talc based bioformulations containing various biocontrol agents against rhizome rot disease caused by Pythium aphanidermatum in turmeric plants was evaluated under field condition. Indigenous biocontrol agents such as Streptomyces lydicus, Streptomyces griseus and Streptomyces sannanensis belonging to actinomycetes group, Pseudomonas fuorescens (bacterial) and Trichoderma atroviride (fungal) were selected for the biological control of rhizome rot of turmeric. The results indicated a signifiicantly stronger reduction in disease severity in trial plots treated with Bacillus subtilis based commercial fungicide ‘Companion’ when compared to plants treated with indigenous biocontrol agents. However, it was reverse in trial plots in terms of turmeric rhizome yield potential, yield attributes, physiological components, biochemical constituents and quality characteristics of rhizomes. Among 17 treatments, a dual mixture of S. griseus and T. atroviride achieved the best disease control as well as plant growth improvement when compared to single and triple combinations of biocontrol agents. The present study confirms that exploration of microbial formulations containing Streptomyces spp. as soil inoculant to turmeric plants exhibited some benefits to turmeric plant growth as well as controlling rhizome rot disease, which ultimately enhance the overall quality characteristics of rhizomes. Further, our results suggest that a dual combination of biocontrol agents represent a promising method for effective management of rhizome rot of turmeric. [ABSTRACT FROM AUTHOR]

Medicated cotton crepe bandages have been developed, using natural curcumin conjugated polymer nanoparticle with biocompatible and biodegradable properties. Curcumin (C) has been incorporated into Chitosan (Ch) and sodium alginate (A) microcapsule, which serve as templates for nanofibres. The coating of C-ChA results in chitosan scaffold (CS) containing curcumin-chitosan microcomplex (CS-CChM). Both the substances act as a powerful biomaterial for tissue engineering applications, especially for wound healing. CS-CChM along with C-ChA have been characterized using FTIR and SEM. The free radical scavenging effect is determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) and anti-inflammatory assay. The developed CS-CChM nanofibre shows an impressive mechanical stability which is an essential requirement for wound healing. The bearing of curcumin shows cytotoxic effect. The in vitro radical scavenging activity and the anti-inflammatory assay are performed by inhibition of albumin denaturation. These microencapsulated matrix displays potent anticancer activity against mouse fibroblast on both normal (L929) and human lung adenocarcinoma (A549) cells. The cell viability is observed to be 51.4 ± 0.71 and 30.53 ± 0.99 respectively for both. CS-CChM nanofibre is found to be stable against enzymatic degradation, which is the most important parameter for promoting the proliferation of cells, contributing to repair and remodeling of tissues during wound healing applications. [ABSTRACT FROM AUTHOR]

An attempt has been made to analyze the architectural traits of six elite tea (Camellia sinensis) clones representing the three principal taxa Assam, China and Cambod with respect to the correlation of blister blight disease (Exobasidium vexans) development. In order to analyze the architecture, branching habit and flushing behavior were observed and subsequently compared with disease incidence. All the clones followed similar architectural pattern irrespective of the cultivar but varied with levels of disease severity. The number of branches was higher in China when compared to Assam and Cambod, branch length was bigger in Assam followed by Cambod and China. Branch angle of all the clones lay well within the described range of theoretical value of 45 to 90°. In general, internodal length was bigger in Assam followed by Cambod and China. These architectural characteristics determined the number of harvestable tea shoots in the bush canopy. China cultivars exhibited an erectophile type of leaf angle, which influenced effective net photosynthesis, transpiration rates and light penetration in leaves. These factors are playing important roles in a disease development strategy. This study should be useful for clonal selection for new clearings and re-planting areas. Moreover, plants breeding programmes for studying the yield and tea quality losses due to blister blight disease benefit from the findings herein. [ABSTRACT FROM AUTHOR]

Tea leaves have economic importance in preparation of the popular beverage of the world "tea". Bird's eye spot disease of tea leaves creates significant revenue loss in tea trade of many tea plant cultivating countries. Management of this disease by silver (AgNps) and copper (CuNps) nanoparticles that are biosynthesised by efficient antagonists was studied. The biocontrol agents like Pseudomonas fluorescens, Trichoderma atroviride and Streptomyces sannanensis were evaluated for nanoparticle synthesis against Cercospora theae isolates namely KC10, MC24 and VC38. Initially, the freshly prepared extracellular AgNps showed high disease control (59.42 - 79.76%), but the stability of antagonistic property in stored nanoparticles were significantly high in CuNps (58.71 - 73.81%). Greenhouse studies on various treatments imposed also showed reduced disease incidence percentage of 13.4, 7.57 and 10.11% when treated with CuNps synthesized by P. fluorescens, T. atroviride and S. sannanensis respectively. Various treatment schedule in fields suggested the use of Bionanocopper@1.5 ppm for highest yield (3743 kg/ha) with 66.1% disease prevention. The results suggest the use of biosynthesised CuNps using Streptomyces sannanensis for controlling the tea plant pathogens causing foliar disease with higher stability in releasing the antagonistic activity during sporadic disease incidence of bird's eye spot disease in tea plants. [ABSTRACT FROM AUTHOR]