Metatranscriptome analysis of symptomatic bitter apple plants revealed mixed viral infections with a putative novel polerovirus.

BACKGROUND: Next-generation Sequencing (NGS) combined with bioinformatic analyses constitutes a powerful approach for identifying and characterizing previously unknown viral genomes. In this study, leaf samples from bitter apple plants (Citrullus colocynthis (L.) Schrad) exhibiting symptoms such as dwarfing, leaf crinkling, and chlorosis were collected from the southern part of Kerman province, Iran. RESULTS: Putative infecting viruses were identified through de novo assembly of sequencing reads using various tools, followed by BLAST analysis. Complete genomes for Squash vein yellowing virus (SqVYV), Citrus-associated rhabdovirus (CiaRV), and a novel polerovirus-related strain termed Bitter apple aphid-borne yellows virus (BaABYV) were assembled and characterized. Additionally, a partial genome for Watermelon mosaic virus (WMV) was assembled. The genomic organization of the BaABYV was determined to be 5'-ORF0-ORF1-ORF1,2-ORF3a-ORF3-ORF3,5-ORF4-3'. Amino acid sequence identities for inferred proteins (P0 and P1, P1,2) with known poleroviruses were found to be the 90% species delineation limit, implying that BaABYV should be considered a new member of the genus Polerovirus. Recombination events were observed in the BaABYV and WMV strains; such events were not found in the CiaRV strain. CONCLUSIONS: Molecular evidence from this study suggests that C. colocynthis is a reservoir host of several plant viruses. Among them, BaABYV is proposed as a new member of the genus Polerovirus. Furthermore, the CiaRV strain has been reported for the first time from Iran.

Environmentally Safe Biosynthesis of Gold Nanoparticles Using Plant Water Extracts.

Due to their simplicity of synthesis, stability, and functionalization, low toxicity, and ease of detection, gold nanoparticles (AuNPs) are a natural choice for biomedical applications. AuNPs' unique optoelectronic features have subsequently been investigated and used in high-tech applications such as organic photovoltaics, sensory probes, therapeutic agents, the administration of drugs in biological and medical applications, electronic devices, catalysis, etc. Researchers have demonstrated the biosynthesis of AuNPs using plants. The present study evaluates 109 plant species used in the traditional medicine of Middle East countries as new sources of AuNPs in a wide variety of laboratory environments. In this study, dried samples of bark, bulb, flower, fruit, gum, leaf, petiole, rhizome, root, seed, stamen, and above-ground parts were evaluated in water extracts. About 117 plant parts were screened from 109 species in 54 plant families, with 102 extracts demonstrating a bioreduction of Au3+ to Au0, revealing 37 new plant species in this regard. The color change of biosynthesized AuNPs to gray, violet, or red was confirmed by UV-Visible spectroscopy, TEM, FSEM, DLS, and EDAX of six plants. In this study, AuNPs of various sizes were measured from 27 to 107 nm. This study also includes an evaluation of the potency of traditional East Asian medicinal plants used in this biosynthesis of AuNPs. An environmentally safe procedure such as this could act as a foundation for cosmetic industries whose quality assessment systems give a high priority to non-chemically synthesized products. It is crucial that future optimizations are adequately documented to scale up the described process.