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Fusarium dieback is a prevalent disease of tea (Camellia sinensis (L.) Kuntze) in India and China. The pathogen affects plucking shoots and causes complete crop loss under favourable conditions. Although, other fungal diseases that infect tea were widely explored for pathogen identification and characterization, little is known about Fusarium dieback in major tea growing regions of India. Therefore, in this study 24 isolates of Fusarium species causing dieback on tea in 24 tea gardens of Assam and North Bengal were isolated and characterized through micro-morphological and molecular analysis using multi-locus DNA sequences to determine whether multiple species of Fusarium are responsible for dieback disease. Molecular analysis revealed the association of four species of Fusarium , namely F. concentricum, F. solani, F. fujikuroi, and F. oxysporum. The most dominant species was F. concentricum (62.5%), whereas the occurrence frequencies of F. solani, F. fujikuroi, and F. oxysporum were 20.8%, 12.5%, and 0.04%, respectively. All Fusarium isolates were pathogenic to tea leaves when individually and co-inoculated, with F. concentricum HPE0F10 and NHT0F17 exhibiting 19.3 mm lesion length being the most virulent isolates. The growth rate of the pathogen was positively correlated with lesion lengths (P < 0.001). Co-infection of two or multiple Fusarium species enhanced the disease severity and quicker disease development compared to single inoculation. All the isolates showed diverse genetic backgrounds based on Inter Simple Sequence Repeat (ISSR) primers and principal coordinate analysis. In fungicide screening test, all isolates except HPE0F10, NDS0F18, and SNY0F22 were insensitive to M1 fungicide (copper oxychloride). Isolates GNP0F8 and LKW0F16 were insensitive to MBC + M3 (Carbendazim + Mancozeb), whereas HPE0F10, NLG0F11, IND0F13, and NLW0F19 were insensitive to DMI (respective each two to Hexaconazole and Valextra) fungicides. Notably, all the isolates were susceptible to propiconazole. Further, ISSR segregated isolates insensitive to MBC + M3 and M1 fungicides into two separate clusters, representing their distinctiveness. The fungicide screening results indicate that fungicide resistance can be managed by rotating different modes of action of fungicides against multiple Fusarium species causing tea dieback. • Fusarium concentricum, F. fujikuroi, F. oxysporum, and F. solani were identified as causal agents of tea dieback. • The identification was confirmed by multi-locus phylogenetic analysis. • Fusarium isolates showed variable pathogenicity through individual and co-inoculation tests. • ISSR primers revealed diverse genetic backgrounds among 24 Fusarium isolates. • Propiconazole was effective against all Fusarium isolates tested. [ABSTRACT FROM AUTHOR]

The biodeterioration of food commodities by microbial pathogens remains a major public health concern. Worldwide, investigations have been carried out to develop harmless natural food preservatives based on essential oils (EOs) to protect food commodities, and advances have been made to meet users' acceptance as a substitute for synthetic preservatives. In recent years, antimicrobial and antioxidant potential of the EOs from Thymus species have been documented with increasing demands from legislation changes, adaptation to the consumer trends, search for alternatives to solve rising food microbial pathogen resistance, and substitution of synthetic preservatives associated with adverse health effects. Hence, the present review paper emphasizes on the antimicrobial and antioxidant applications of EOs from different species of the genus Thymus and discloses the gaps where investigations are required. In addition, progress in the using Thymus EOs (TEOs) based nanoemulsions in food preservation, and their challenges in the application in food systems have also been discussed. TEOs are rich in pharmacologically active constituents that confirm their industrial and health applications. In addition, TEOs and their nanoemulsions not only provide themselves to exploit in the food industry, but are also put under GRAS (Generally Recognized As Safe) category, and have shown potential inhibitory activity against a broad range of pathogens in food commodities. Thus, TEOs can be a source for the development of natural preservatives that meet the needs of the food industry to satisfy both its requirements and those of the consumers. However, despite the potential for EOs, more studies are required to assess their probable side effects and safety levels before considering their deployment for food purposes. [Display omitted] • Biological activities of Thymus essential oils (TEOs) were reviewed. • Microorganisms deteriorating foodstuffs were re-studied. • Phytochemical properties of biologically active TEOs were explained. • Exploitation of TEOs and their nanostructures in food preservation was discussed. • Challenges in using TEOs in food systems were addressed. [ABSTRACT FROM AUTHOR]

Pestalotiopsis -like species are necrotrophic fungi, which infect many annual and perennial crops, including agricultural, horticultural, and plantation crops, in postharvest and under field conditions worldwide. They cause multiple diseases on crops, which results in severe yield loss. At present, Pestalotiopsis- like species cause gray blight on tea, which is a widely prevalent disease in major tea-growing countries and rapidly spreading in other tea-growing countries of minor importance due to climate change. The global increase in disease incidence and severity and the emergence of new virulent isolates have prompted research on the evolution of pathogenic determinants in these fungal species. This review synthesizes the epidemiology, molecular and genetic studies of the gray blight pathogen with particular reference to tea crop and the approaches to mitigate it. Further, the adaptation of Pestalotiopsis- like species on other crops and their management strategies are also discussed along with potential areas for future research. • In many crops, including tea, Pestalotiopsis -like species cause gray blight. • Morpho-molecular detection of Pestalotiopsis -like species are summarised. • Molecular studies on Pestalotiopsis -like species infecting tea plants are discussed. • Management strategies for Pestalotiopsis -like species are discussed along with potential gaps. [ABSTRACT FROM AUTHOR]

In the present laboratory bioassay, antibacterial activity of 22 Asteraceae essential oils were evaluated against two phytopathogenic bacteria Erwinia herbicola (Lohnis) and Pseudomonas putida (Kris Hamilton). Of 22 oils, Eupatorium adenophorum Spreng oil exhibited highest toxicity against both bacteria followed by Artemisia nilagirica Linn., Blumea eriantha DC., Blumea lacera (Burm.f.) DC and Tagetes erecta Linn oils. During MIC and MBC determination, E. adenophorum oil displayed its superiority over the other four toxic oils as well as antibiotics (agromycin and streptomycin) with MIC and MBC values ranges of 0.25–4.0 µl ml −1 for both bacterial species. GC and GC–MS analysis of E. adenophorum oil revealed that the oil was mixture of 35 major and minor components. Among these components, acoradiene (10.11%), bornyl acetate (10.60%), camphene (12.05%), p -cymene (11.6%) and α-phellandrene (8.57%) represent higher percent composition. E. adenophorum oil showed potent antioxidant activity and IC 50 values were 8.3 and 4.2 µl, when tested by DPPH and β-carotene bleaching methods, respectively. The findings concluded that E. adenophorum oil may be supplemented as potent antibacterial and antioxidant agent in food and pharmaceutical systems. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol-A (BPA), a toxic chemical from polycarbonate plastics, is known for behavioural and neural abnormalities. These neuro-behavioural changes reflect the changes in neural activity. However the effect of BPA on nerve action potential is not available. Therefore, present investigation was undertaken to study the effect of BPA on compound action potential (CAP) of frog sciatic nerve. Bundle containing small group of nerve fibres in a sciatic nerve was dissected and placed in a Perspex chamber perfused with Ringer solution. Suction electrodes were applied to the cut ends of the nerve for stimulating and recording purposes. The stimulation of one end (with supramaximal strength) produced CAP in the recording electrode. BPA (1–100μM) decreased the amplitude and repolarization time of CAP in a concentration-dependent manner, without any alteration in latency, rise time and threshold. The decrease in amplitude was directly correlated with decrease in repolarization time (r =0.76). The BPA-induced decreases were absent in Ca2+-free medium or in presence of L-type Ca2+-channel antagonist (nifedipine/deltiazem). T and P type Ca2+ channel antagonist (Ni2+) failed to block the BPA-induced responses. Pre-treatment with an Erα antagonist (tamoxifen) blocked the BPA-induced decrease in CAP parameters. These observations indicate that the BPA decreased the amplitude and repolarization time of CAP involving L-type Ca2+-channel dependent mechanisms. Further involvement of Erα in the modulation of Ca2+ channels is a possibility. [Copyright &y& Elsevier]

Dry root rot (DRR), caused by Macrophomina phaseolina , is a prevalent disease of mungbean in Myanmar, and an emerging problem in South Asia. The pathogen is a polyphagous necrotroph, survives in the soil for many years that results disease mitigation difficult. Managing DRR in mungbean through an integrated approach has been suggested, and the use of resistant varieties is one of the economical methods. The present study aimed to identify sources of resistance against DRR from a mungbean mini-core collection and to characterize the associated M. phaseolina isolates from India and Myanmar. Evaluation of the 296 mungbean mini-core accessions against the isolate MP1 by paper towel method identified 29 accessions with DRR resistance (disease scores: ≤ 3), and 18 of them with the consistent resistance in the repeated experiment. During the screening of 18 resistant accessions in the glasshouse, nine accessions were found DRR resistance in repeated sick pot experiments with ≤10% disease incidence. A subset of 30 accessions was selected from the mini-core collection based on their in vitro DRR reactions. These accessions were evaluated for DRR resistance in the field in Yezin, Myanmar in 2018 and 2019. Out of the 30 accessions, ten accessions were found DRR resistance with ≤10% disease incidence in both years of evaluations. Pooled analysis of percent disease incidence data of 15 accessions common in both glasshouse and field revealed the stability of accessions VI001509AG, VI001244AG, and VI001400AG for DRR resistance across years and locations. The three resistant accessions along with a susceptible check VC693088 were re-evaluated by paper towel method against nine additional M. phaseolina isolates from India (MP3-MP11). The accessions VI001509AG and VI001400AG were resistant to all nine isolates, while accession VI001244AG was resistant to MP5, MP6, and MP7 isolates. These accessions could be used in mungbean DRR resistance breeding programs. • Macrophomina phaseolina isolated from mungbean from different regions showed morpho-cultural and pathological variability. • In vitro screening of 296 mungbean mini-core accessions against DRR identified 29 accessions with resistance. • Nine accessions in the glasshouse and ten accessions in the field showed DRR resistance. • GGE biplot analysis revealed that accessions VI001509AG, VI001244AG, and VI001400AG with stable DRR resistance. • Accessions VI001509AG and VI001400AG showed resistance against nine M. phaseolina isolates from India. [ABSTRACT FROM AUTHOR]

Background: Terminalia bellirica (Gaertn.) Roxb. is one of the oldest medicinal herbs of India, Pakistan, Nepal, Bangladesh and Sri Lanka as well as South-East Asia. Its medicinal utility has been described in the different traditional medicinal systems, such as Ayurveda, Unani, Siddha, and traditional Chinese medicine.Purpose: The present study is aimed at providing a comprehensive overview on the traditional medicinal use, major phytoconstituents, biological and pharmacological activities and related mechanisms of actions and clinical studies of T. bellirica. Another objective is to describe current limitations and future direction of T. bellirica-related research.Methods: PubMed, ScienceDirect, Scopus, Cochrane Library, and EBOSCO host databases were selected to explore literature published between 1980 and 2020 (till March). Keywords used in various combinations comprised of Terminalia bellirica, phytoconstituents, health effects, pharmacological activities, molecular targets, in vitro, in vivo, clinical studies, and disease prevention.Results: A broad spectrum in vitro and in vivo studies suggested various biological and pharmacological effects, including antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, hepatoprotective, renoprotective, antidiabetic, anti-hyperlipidemic, and anticancer activities. Diverse bioactivities of T. bellirica have been ascribed to the presence of many bioactive phytochemicals, such as glucoside, tannins, gallic acid, corilagin, ellagic acid, ethyl gallate, galloyl glucose, chebulagic acid, and arjunolic acid.Conclusion: Preclinical and clinical studies have suggested that T. bellirica plant and its phytoconstituents have immense potential for prevention and treatment of various diseases. Additional in vivo studies and clinical trials are warranted to realize the complete medicinal attributes of this plant. [ABSTRACT FROM AUTHOR]

Dry root rot (DRR) is an important emerging disease of mungbean caused by fungus Macrophomina phaseolina. The disease is seed and soil-borne and hence management is difficult. Exploitation of host resistance could be a good option to manage the disease. The objectives of this study were to characterize the isolates of M. phaseolina from three legume crops and to identify resistant sources against DRR of mungbean. Isolates of M. phaseolina from mungbean, urdbean, and vegetable soybean were identified using morphological characteristics and sequencing internal transcribed sequence (ITS) region of 18S rRNA. Isolates of M. phaseolina from urdbean and vegetable soybean were inoculated on susceptible check genotype of mungbean to assess their pathogenicity. Forty three mungbean genotypes were screened against M. phaseolina isolate of mungbean using the paper towel method to identify sources of resistance. Among these genotypes, 9 were resistant in repeated experiment, with disease score ranging from 1.9 to 3.0. Resistant genotypes showing lower disease score, namely IPM99-125, EC693368, and EC693369, were further screened using the sick pot method to confirm their resistance. Among these three genotypes, IPM99-125 showed consistently higher plant survival rate followed by EC693368 and EC693369 as compared to susceptible checks (VC3960-88, KPS1). In addition, these three genotypes were resistant when screened with two strains of M. phaseolina isolated from urdbean and vegetable soybean, with IPM99-125 having lower disease score. The mungbean genotype IPM99-125 could be useful in mungbean breeding programs to develop root rot-resistant varieties. • Macrophomina phaseolina isolated from mungbean, urdbean and vegetable soybean showed identical cultural and molecular characteristics. • Screening of 43 mungbean genotypes against DRR revealed resistance of IPM99-125, EC693368 and EC693369 genotypes. • The above three genotypes also showed resistance against M. phaseolina isolated from urdbean and vegetable soybean. • Genotype IPM99-125 exhibited higher plant survival could be useful in mungbean breeding programs to develop DRR resistant varieties. [ABSTRACT FROM AUTHOR]

Background: Aloe vera is commonly used in the primary health care of human beings since time immemorial. It is an herb widely used in various traditional systems of medicine worldwide. Systematic and scientific investigation on A. vera as a medicinal plant has drawn considerable attention, and many laboratories are involved in isolation, characterization and evaluation of phytoconstituents for their nutraceutical and pharmaceutical applications.Purpose: The aim of this study was to provide an overview of the phytochemical, biological and medicinal attributes of A. vera against various diseases with special emphasis on underlying mechanisms of action.Methods: PubMed, EBOSCO host, Science Direct, Scopus, and Cochrane library databases were utilized to search literature published between1977 and 2019 (till March). Major keywords used in various combinations included: Aloe vera, phytochemistry, metabolism, pharmacological activity, prevention, treatment, health, disease, in vivo, in vitro, and clinical studies.Results: Various biological and pharmacological activities of A. vera, such as antioxidant, anti-inflammatory, immuno-modulatory, antimicrobial, antiviral, antidiabetic, hepatoprotective, anticancer, and skin-protective and wound-healing responses, have been attributed to the presence of many active compounds, including anthraquinones, anthrones, chromones, flavonoids, amino acids, lipids, carbohydrates, vitamins and minerals.Conclusion: Based on various preclinical studies, A. vera constituents have enormous potential to prevent and treat various diseases. Randomized clinical trials are needed to understand the full therapeutic potential of this unique medicinal plant. [ABSTRACT FROM AUTHOR]

Root exudates are a complex group of organic substances that mediate plant–microbe interactions in the rhizosphere. Plants modify their root exudates to cope with abiotic and biotic stress factors. Understanding factors affecting the root exudation requires an in-depth analysis of this process across contrasted environmental conditions and cropping practices. Cropping practices may attenuate the negative effects of climate change by steering root exudation process that foster recruitment of beneficial organisms and repeal the detrimental ones. Steering root exudation processes via crop management is an important way for sustainable management of soil-borne disease complexes. Ongoing climate change will both profoundly impact land-use (e.g., changes in crop species or cultivar and cropping practices) and abiotic factors (e.g., moisture and temperature), which will in turn alter plant–microorganism interactions in soils, including soil-borne pathogens (i.e., plant pathogenic bacteria, fungi, oomycetes, viruses, and nematodes). These pathogens often cause soil-borne disease complexes, which, due to their complexity, frequently remain undiagnosed and unmanaged, leading to chronic yield and quality losses. Root exudates are a complex group of organic substances released in the rhizosphere with potential to recruit, repel, stimulate, inhibit, or kill other organisms, including the detrimental ones. An improved understanding of how root exudates affect interspecies and/or interkingdom interactions in the rhizosphere under ongoing climate change is a prerequisite to effectively manage plant-associated microbes, including those causing diseases. [ABSTRACT FROM AUTHOR]

• Terminalia bellerica fruits extracts (ethyl acetate and aqueous fractions) exhibited strong free radical scavenging activity, reducing power and total antioxidant capacity. • Fruit ethyl acetate extracts possess higher amount of phenolic and flavonoid contents as compared with aqueous extracts. • Both the extracts possess notable α-amylase inhibitory activity during in vitro evaluation suggesting antidiabetic potential. • Extracts exhibited hypoglycemic effect in alloxan induced diabetic rats and regulated hepatic and renal functions. Excessive production of free radicals in the living system leads to oxidative stress which is associated with degenerative disorders including diabetes. Diabetes is increasing at a rapid pace despite the availability of synthetic anti-hyperglycemic drugs in the market. Hence antioxidant and anti-diabetic compounds of natural origin have attracted attention for drug development. The aim of the present study was to investigate the phytochemical composition, antioxidant potential, α-amylase inhibitory and antidiabetic activity of aqueous (AQ) and ethyl acetate (EA) extracts of Terminalia bellirica fruit. Chemical methods were employed for phytochemical analysis. Antioxidant activities of extracts were measured using in vitro assays viz., DPPH free radical scavenging, reducing power, hydroxyl radical scavenging and phosphomolybdate assays. The antidiabetic potential was measured by in vitro α-amylase inhibitory activity and in vivo serum biochemical assays in alloxan-induced diabetic rats. Chemical analysis showed the presence of phenols, flavonoids, alkaloids, terpenoids, saponins and glycosides as a major phytochemical in AQ and EA extracts of T. bellirica fruit. Quantitatively EA extract showed the presence of higher content of phenolics and flavonoids as compared to AQ extract. Further EA extract exhibited considerable free radical scavenging abilities in DPPH and HRSA assays (up to 94%), reducing power assay and appreciable total antioxidant power in phosphomolybdate assay (78 μgPGE/g). The EA extract exhibited comparatively better α-amylase inhibitory activity (IC50 43.5 μg/ml) as compared to AQ extract (IC50 74.8 μg/ml). The activity was comparable to standard drug acarbose. Antidiabetic activity of extracts was studied in alloxan-induced diabetic rats by monitoring the body weight, blood glucose, lipid profile and other biochemical parameters for 28 days. In diabetic rats both the extracts showed a restorative effect on body weight and blood biomarkers such as glucose, creatinine, total protein, total cholesterol, LDL, HDL, triglyceride, urea and uric acid. The ethyl acetate extract also exhibited superiority over the aqueous extracts during in vivo antidiabetic assays. The results revealed that T. bellirica fruit extracts possess antioxidant, α-amylase inhibitory and antidiabetic activities and hence it could be useful for the management of hyperglycemia and oxidative stress. [ABSTRACT FROM AUTHOR]

Moringa oleifera Lam belonging to family Moringaceae is a plant with high nutritional and medicinal value. The plant is native to India; however, it is now spread to the tropical and subtropical regions of the world. The genus consists of 13 species and they are being cultivated in Asia, Africa and another part of the world for the multiple uses. Different part of the plants is a rich source of protein, lipid, carbohydrates, amino acids, vitamin and minerals. Hence, it is used as dietary supplements in the tropics as a nutrient source where malnutrition is a major concern, especially in children and infants. Seeds of the plant have coagulant and bio sorbent property which allows it to be used in purifying water quality and reduce the microbial load. The present review highlights information regarding the traditional uses, phytoconstituents, pharmacological attributes viz., antioxidant, anticancer, hepatoprotective, antimicrobial, antiviral, anti-inflammatory, neuroprotective etc. and toxicological aspects of M. oleifera species in order to explore further their therapeutic potential and assess future research dimensions. • Moring oleifera is a rich source of protein, fats, carbohydrates, vitamins and minerals. • Seeds of the plant are widely used for water purification. • Plant is reservoir of bioactive secondary metabolites which are mainly responsible for its medicinal value worldwide. • No adverse effects of this plant have been reported. [ABSTRACT FROM AUTHOR]