RESUMEN
Chilli (Capsicum annuum L.) is an important vegetable crop grown in the Indian sub-continent and is prone to viral infections under field conditions. During the field survey, leaf samples from chilli plants showing typical symptoms of disease caused by cucumber mosaic virus (CMV) such as mild mosaic, mottling and leaf distortion were collected. DAC-ELISA analysis confirmed the presence of CMV in 71 out of 100 samples, indicating its widespread prevalence in the region. Five CMV isolates, named Gu1, Gu2, BA, Ho, and Sal were mechanically inoculated onto cucumber and Nicotiana glutinosa plants to study their virulence. Inoculated plants expressed the characteristic symptoms of CMV such as chlorotic spots followed by mild mosaic and leaf distortion. Complete genomes of the five CMV isolates were amplified, cloned, and sequenced, revealing RNA1, RNA2, and RNA3 sequences with 3358, 3045, and 2220 nucleotides, respectively. Phylogenetic analysis classified the isolates as belonging to the CMV-IB subgroup, distinguishing them from subgroup IA and II CMV isolates. Recombination analysis showed intra and interspecific recombination in all the three RNA segments of these isolates. In silico protein-protein docking approach was used to decipher the mechanism behind the production of mosaic symptoms during the CMV-host interaction in 13 host plants. Analysis revealed that the production of mosaic symptoms could be due to the interaction between the coat protein (CP) of CMV and chloroplast ferredoxin proteins. Further, in silico prediction was validated in 13 host plants of CMV by mechanical sap inoculation. Twelve host plants produced systemic symptoms viz., chlorotic spot, chlorotic ringspot, chlorotic local lesion, mosaic and mild mosaic and one host plant, Solanum lycopersicum produced mosaic followed by shoestring symptoms. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03777-8.
RESUMEN
Garden croton (Codiaeum variegatum L.) plants showing typical begomovirus symptoms of vein twisting, enation and curling were collected from different gardens at Varanasi, Uttar Pradesh state of India ranged from 20 to 30%. All the 10 ten (CR1-CR10) infected samples of garden croton resulted in expected amplicon of 1.2 Kb in PCR specific to begomoviruses. No amplification was obtained for betasatellite and alphasatellite specific primers. The complete genome sequence of DNA-A and DNA-B for two isolates (CR1 and CR2) was obtained through rolling cycle amplification (RCA) and comparisons were made with other begomoviruses using Sequence Demarcation Tool (SDT) which revealed that, DNA-A of two isolates, CR1 (Acc.No.: MW816855) and CR2 (Acc.No.: MW816856) showed maximum nucleotide (nt) identity of 85.7-85.9% with Tomato leaf curl Karnataka virus, which is below the threshold percentage of begomovirus species demarcation, hence considered as novel begomovirus and proposed the name Garden croton enation leaf curl virus (CroELCuV) [IN: Varanasi: Croton: 18]. Further, DNA-B these isolates shared maximum nt identity of 91.0-92.2% (DNA-B) with Tomato leaf curl New Delhi virus. Recombination and GC plot analysis showed that the recombination occured at in low GC content regions of DNA-A and DNA-B of the CroELCuV and are derived from the previously reported several begomoviruses. This is the first record of novel bipartite begomovirus associated with vein twisting, enation and leaf curling of disease of garden garden croton in India and world. Supplementary Information: The online version contains supplementary material available at 10.1007/s13337-022-00772-0.
RESUMEN
The Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in outbreak of global pandemic, fatal pneumonia in human referred as Coronavirus Disease-2019 (Covid-19). Ayurveda, the age old practice of treating human ailments in India, can be considered against SARS-CoV-2. Attempt was made to provide preliminary evidences for interaction of 35 phytochemicals from two plants (Phyllanthus amarus and Andrographis paniculata used in Ayurveda) with SARS-CoV-2 proteins (open & closed state S protein, 3CLpro, PLpro and RdRp) through in silico docking analysis. The nucleotide analogue remdesivir, being used in treatment of SARS-CoV-2, was used as a positive control. The results revealed that 18 phytochemicals from P. amarus and 14 phytochemicals from A. paniculata shown binding energy affinity/dock score < - 6.0 kcal/mol, which is considered as minimum threshold for any compound to be used for drug development. Phytochemicals used for docking studies in the current study from P. amarus and A. paniculata showed binding affinity up to - 9.10 kcal/mol and - 10.60 kcal/mol, respectively. There was no significant difference in the binding affinities of these compounds with closed and open state S protein. Further, flavonoids (astragalin, kaempferol, quercetin, quercetin-3-O-glucoside and quercetin) and tannins (corilagin, furosin and geraniin) present in P. amarus have shown more binding affinity (up to - 10.60 kcal/mol) than remdesivir (up to - 9.50 kcal/mol). The pharmacokinetic predictions suggest that compounds from the two plants species studied in the current study are found to be non-carcinogenic, water soluble and biologically safe. The phytochemicals present in the extracts of P. amarus and A. paniculata might have synergistic effect with action on multiple target sites of SARS-CoV-2. The information generated here might serve as preliminary evidence for anti SARS-CoV-2 activity of phytochemicals present from P. amarus and A. paniculata and the potential of Ayurveda medicine in combating the virus. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-020-02578-7.