Search

Citrus is one of the most important and widely grown fruit crops around the world. Citrus fruit drop is due to the influence of various biotic and abiotic factors. Major biotic factors include insects like fruit flies and diseases such as Huanglongbing (HLB) and postbloom fruit drop (PFD) due to Colletotrichum acutatum. The associated abiotic factors are temperature, rainfall, hailstorms, water stress, nutritional imbalance, etc. Studies have been conducted to understand fruit drop and its relation to various plant growth regulators. Plant growth regulators such as auxin and gibberellins have been categorised as abscission inhibitors, while ethylene, abscisic acid (ABA) and methyl jasmonate (MJ) are abscission promoters. Here, in this review, we have emphasised on the different phases of fruit drops, factors causing fruit drop, the role of plant growth regulators, fruit detachment force (FDF), rootstocks, water relation, nutrient status and different chemical, biological, botanical and hormonal strategies applied for controlling citrus fruit drop. Moreover, we have also discussed the molecular basis of citrus fruit drop and have reviewed recent studies involving biosynthesis/signalling pathway genes and phytohormone genes affecting fruit drop. This review offers comprehensive information about citrus fruit drop and shall provide the direction of future research for students, horticulturists, researchers and other stakeholders.

C3HC4-type RING finger gene family is one of the largest, ubiquitous, and diverse proteins, involved in positive regulation of stress response, and enhances drought and salt stress tolerance. The genome-wide characterisation and biological functions of this family protein are well characterised in several plants and animals. However, their characterisation and functions in Capsicum and its related species are unknown. In this study, we identified 16 C3HC4-type RING finger family genes in pepper (Capsicum annuum L). Moreover, chromosome localisation, gene structure, phylogenetic relationships, conserved domain analysis, and cis-element analysis were carried out. In silico expression analysis was carried out to determine the level of expression of these genes in different tissues of pepper. Moreover, RT-qPCR analysis validated that CaRHC1, CaRHC7, and CaRHC13 are upregulated, while CaRHC3, CaRHC4, and CaRHC6 are downregulated in various tissues of pepper. Upregulation and downregulation of few candidate C3HC4-type RING finger genes in the placenta and pericarp of pepper indicates their possible role in capsaicin biosynthesis and pungency, which needs to be investigated further. Thus, the genome-wide analysis provides a comprehensive understanding of C3HC4-type RING finger gene family in Capsicum genome and it shall help to design effective strategies for functional analysis of these genes.

The study was designed to elucidate the potential of jackfruit clonal accessions having diverse flake colours from nutritional and medicinal perspectives. Jack fruit accessions with deep yellow flakes were found to contain the highest flavonoids, antioxidant activity, ascorbic acid, and α-glucosidase inhibition whereas, orange-red flakes exhibited the highest β-carotene, phenol, minerals (iron and zinc) and better inhibition of α-amylase and β-glucosidase enzymes. Phenolic compounds profiling revealed the presence of higher sinapic acid, ferulic acid and quercetin contents in the orange-red-coloured flakes. Metabolite analysis revealed presence of anti-diabetic compounds (n-Hexadecanoic acid, tridecane, 2-Heptadecenal etc.) in deep yellow and orange-red coloured jack flakes with lower glycemic load. Considering the abundant health benefits as evident from the present study, orange-red and deep yellow-coloured flakes may be recommended for consumption to manage the hyperglycemic condition.

Chikungunya virus (CHIKV) infection and subsequent high patient morbidity is a global threat. The present study aimed to identify the potent antiviral agent against Chikungunya virus, with minimum in vitro cytotoxicity. CHIKV nsP4 3D structure was determined using the I-TASSER server followed by its refinement and pocket determination. Furthermore, high-throughput molecular docking was employed to identify candidate CHIKV nsP4 inhibitors in a library containing 214 compounds. The top ranked compound was evaluated further with various assays, including cytotoxicity, antiviral activity, time of drug addition, viral entry attachment, and microneutralization assays. High-throughput computational screening indicated silibinin to have the best interaction with CHIKV nsP4 protein, immature and mature glycoproteins with highest negative free binding energy, - 5.24 to - 5.86 kcal/mol, and the lowest inhibitory constant, 50.47 to 143.2 µM. Further in vitro analysis demonstrated silibinin could exhibit statistically significant (p 0.05) dose-dependent anti-CHIKV activity within 12.5-100-µM concentrations with CC

Following the disruptive epidemics throughout the Indian Ocean, Southeast Asia and the Americas, efforts have been deployed to develop an effective vaccine against chikungunya virus (CHIKV). The continuous threat of CHIKV (re-)emergence and the huge public health and economic impact of the epidemics, makes the development of a safe and effective vaccine a priority. Several platforms have been used to develop candidate vaccines, but there is no consensus about how to translate results from preclinical models to predict efficacy in humans. This paper outlines a concept of what constitutes an effective vaccine against CHIKV, which may be applied to other viral vaccines as well. Defining endpoints for an effective vaccine is dependent on a proper understanding of the pathogenesis and immune response triggered during infection. The preclinical model adopted to evaluate experimental vaccines is imperative for the translation of preclinical efficacy data to humans. Several CHIKV animal models exist; however, not all provide suitable endpoints for measuring vaccine efficacy. This review summarizes the current knowledge related to CHIKV pathogenesis and the correlates of protection. We then define what would constitute an effective CHIKV vaccine in humans using four key endpoints, namely: (i) prevention of chronic disease, (ii) prevention of acute disease, (iii) prevention of transmission to mosquitoes, and (iv) complete prevention of infection. Lastly, we address some of the gaps that prevent translation of immunogenicity and efficacy findings from preclinical models to humans, and we propose to use the combination of virus–cytokine–ferritin levels as a read-out for measuring vaccine-induced protection.

With increasing agricultural production after green revolution in India, generation of agricultural waste is a concern for clean agricultural production system. The purpose of the study is to recycle locally available agricultural wastes into vermicompost and apply it on crops. In this study vermicomposts prepared from combinations of four sources of each plant biomass and animal excreta were characterized and tested for yield and quality of green bell pepper (Capsicum annum L.). Vermicompost samples were analyzed for macronutrients, micronutrients and enzymatic activities at intermediate (40 d) and final (80 d) stages of decomposition. During composting, total organic carbon content of the bedding material decreased and C: N ratio was narrowed down. Zinc, Cu, and Mn contents were decreased by 6.9–177.3%, 28.5–318.5% and 0.7–207.4%, respectively, while Fe content increased by 15.4–64.3% in the matured samples. Acid phosphomonoesterase and dehydrogenase activities were reduced by 2.5–26.0% and 15.5–84.1%, respectively; while the β-glucosidase activity of vermicompost from cow dung and pig dung was increased by 2.0–30.7% at maturity. Application of vermicompost along with NPK fertilizers enhanced morphological, biochemical and yield attributes of green bell pepper which in-turn improved yield (7.1–135.7%) over the control. Vermicomposts also improved soil fertility by increasing organic C and plant-available N, P and K. Hierarchical cluster analysis revealed that the properties of mature vermicomposts were mainly determined by the animal excreta. Poultry litter along with paddy straw and Azolla pinnata proved to be superior raw material in the production of high quality vermicompost which could produce good quality and quantity of fruits. The study also suggests that production of vermicompost from locally available plant biomass and animal excreta will sustain crop harvest with quality produce and improve soil fertility.

This is the first study reporting whole genome sequences of two CHIKV strains (KJ679577 and KJ679578) isolated from Eastern Indian patients sera during 2010–2011 outbreak, both of which were of ECSA genotype, but from different subgroups: Indian Ocean outbreak and ECSA subtypes. Furthermore, viral sequences were analyzed using different in-silico approaches to identify potential genetic variations that might have functional implications on various aspects of virus replication, viral protein functionality, immunogenicity and transmission. Epitope prediction analysis revealed 70.9% increase in number of MHC Class-II interacting epitopes of KJ679578 and 25–28% increase in Class-I interacting epitopes of KJ679577 and KJ679578 compared to that of EF027141 (CHIKV of Asian genotype circulating in India during 1973, after which CHIKV infection disappeared from India for three decades). CHIKV peptides DLAKLAFKRSSKYDLECAQIPVHMKSDA and KVVLCGDPKQCGFFNMMQMKYNYNHNI were predicted to interact with maximum number of HLA Class-I (68 and 76.5%, respectively) and Class-II (47 and 100%, respectively) alleles present within Indian population with allele frequency of > 0.1 and were also recognized as predicted B-cell epitopes with BCPred score between 0.766 and 0.961 and with antigenicity ranging from 0.52 to 1.69; thus these peptides might be used to induce T- and B-cell-mediated immunity against CHIKV. Thus, the present study might help to bridge the gap between virus microevolution and its implication in host immunity by taking into account viral genetic and conformational changes. Predicted epitopes might be used as promising targets for peptide-based vaccine development and rapid diagnostics against CHIKV infection. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13205-018-1339-3) contains supplementary material, which is available to authorized users.

Chikungunya virus (CHIKV) infection leads to activation of innate immune response by triggering Toll-like receptor (TLR) pathways resulting in elevated cytokines and type-I interferon levels. Genetic variations of these genes may influence human CHIKV-susceptibility and disease progression. Present study aimed to identify role of TLR polymorphisms in CHIKV-susceptibility and their association with cytokines and clinical symptoms. This is the first study illustrating certain genotypes of TLR-7 and TLR-8 SNPs viz. CT(p = 0.002)]; rs3853839[GC(p < 0.001), CC(p = 0.039)] and rs3764879[GC(p < 0.001)] were considerably associated with CHIKV susceptibility. Increased risk of CHIKV infection among male patients with CC-genotype (rs179010) (p = 0.028) and female patients with GT-genotype (rs5741880) (p = 0.019) was observed. Significant higher IFN-α (P = 0.002) levels among chikungunya TNF-α (P = 0.034) patients was reported. Chikungunya patients with rs179010-CC genotype showed significantly high IFN-α level(p = 0.003). Thus, these TLR variants might act as potential prognostic biomarkers for predicting CHIKV susceptibility among uninfected individuals.

During last three decades, dengue (DF), an arthropod-borne viral disease is increasingly prevalent worldwide including India, resulting in serious public health problems.This study was carried out during 2012-2013 to evaluate the association of WHO-classified dengue disease symptoms with viral load (VL) and serum IFN-gamma levels in dengue patients from India.Blood samples were collected from dengue symptomatic febrile patients (n=127). DEN-VL was determined by quantitative real-time RT-PCR using RNA, extracted from plasma and anti-DENV-IgM was detected by ELISA. Serum IFN-gamma level was detected by ELISA among DENV infected and age-matched control individuals. Association between DEN-VL and IFN-gamma level in patient's sera with WHO-classified disease symptoms was statistically analyzed.DENV RNA and anti-DENV-IgM was detected among 94% (n=73) and 36% (n=28) of dengue infected patients (n=78) respectively. Fever, nausea, rash, achespains, leucopenia and persistent vomiting were significantly correlated with DENV infection (P-value0.05). Only patients with high-VL exhibited leucopenia, persistent vomiting, abdominal pain and clinical fluid accumulation, which were warning signs of dengue infection according to revised WHO-criteria (P-value0.05). Clinical symptoms of DENV infected patients, viz. leucopenia, abdominal pain and persistent vomiting were significantly correlated to each other (P-value0.05). Increased serum IFN-gamma level was detected among dengue patients compared to control individuals. DEN-VL and symptoms like nausea, leucopenia, persistent vomiting and abdominal pain were significantly negatively correlated with serum IFN-gamma level (P-value0.05).Serum IFN-gamma level and dengue viremia among acute stage patients might be used as early prognostic marker for disease severity prediction.

After a gap of three decades, from 2005 onwards, a series of Chikungunya virus (CHIKV) outbreaks occurred worldwide. This study was performed to detect CHIKV infection, its genotype among symptomatic Eastern Indian patients and to analyze any association between the presence of CHIKV genome in patient body with appearance of disease symptoms (n = 199). Plasma-extracted viral RNA was reverse transcribed to cDNA and PCR-amplified followed by agarose gel electrophoresis. Viral load among CHIKV-positive patients was determined by real time RT-PCR. CHIKV-IgM in sera was detected by ELISA. Sequencing and phylogenetic analysis of plasma-extracted PCR products was done. CHIKV genome and IgM were detected among 65.3% (n = 130) and 41.2% (n = 82) patients respectively. Joint swelling was significantly associated with CHIKV infection (P-value: 0.0003). CHIKV PCR positive patients were grouped in two categories: Group-I: viral load

Pathogenic Klebsiella pneumoniae, resistant to beta-lactam and quinolone drugs, is widely recognized as important bacteria causing array of diseases. The resistance property is obtained by acquisition of plasmid encoded blaTEM, blaSHV, blaCTX-M, QNRA, QNRB and QNRS genes. The aim of this study was to document the prevalence and association of these resistant genes in K. pneumoniae infecting patients in India. Approximately 97 and 76.7 % of the 73 K. pneumoniae isolates showed resistance towards beta-lactam and quinolone drugs respectively. Bla genes were detected in 74 % of K. pneumoniae isolates; with prevalence in the following order: blaTEM > blaSHV > blaCTXM. QNR genes were detected in 67 % samples. Chi-square analysis revealed significant association between presence of bla and qnr genes in our study (P value = 0.000125). Sequence analysis of some blaTEM, blaSHV, blaCTX-M and QNRB PCR products revealed presence of blaTEM1 (GenBank accession: JN193522), blaTEM116 (JN193523 and JN193524), blaSHV11, blaCTXM72 variants (JF523199) and QNRB1 (JN193526 and JN193527) in our samples.

After a gap of three decades, from 2005 onwards, a series of Chikungunya virus (CHIKV) outbreaks occurred worldwide. This study was performed to detect CHIKV infection, its genotype among symptomatic Eastern Indian patients and to analyze any association between the presence of CHIKV genome in patient body with appearance of disease symptoms (n = 199). Plasma-extracted viral RNA was reverse transcribed to cDNA and PCR-amplified followed by agarose gel electrophoresis. Viral load among CHIKV-positive patients was determined by real time RT-PCR. CHIKV-IgM in sera was detected by ELISA. Sequencing and phylogenetic analysis of plasma-extracted PCR products was done. CHIKV genome and IgM were detected among 65.3% (n = 130) and 41.2% (n = 82) patients respectively. Joint swelling was significantly associated with CHIKV infection (P-value: 0.0003). CHIKV PCR positive patients were grouped in two categories: Group-I: viral load10(4) copies/ml and Group-II: viral load ≥10(4) copies/ml. Higher number of acute stage patients clustered in Group-II. Fever and joint swelling were significantly more prevalent among Group-II patients, whereas rash and diarrhoea among Group-I patients (P-value0.05). Patient-isolated CHIKV sequences clustered with CHIKV ECSA genotypes in the phylogenetic tree, with two types of CHIKV strains found to circulate among them-as indicated by their different nucleotide sequences. This is the first study detecting the presence of CHIKV ECSA genotype among Eastern Indian patients. Fever and joint swelling might have appeared first followed by rash, diarrhea during disease progression-as indicated by CHIK viral load in patients. Thus, viral load can be used as unique diagnostic and prognostic marker of Chikungunya disease pathogenesis.