Smriti Mall

Marigold is an economically important ornamental crop widely cultivated across India. The present study reports the molecular detection and identification of phytoplasmas associated with virescence symptoms, including flower green structures and abnormal development in marigold from Gorakhpur, Uttar Pradesh, India. With PCR and nested PCR assays the presence of phytoplasmas in symptomatic samples was confirmed. The obtained 1.25 kb amplicon was sequenced and showed 98.87% identity with ‘Candidatus Phytoplasma asteris’ reference strain. RFLP analysis further confirmed that the strain belongs to the 16SrI-B subgroup. Although this subgroup has previously been reported from marigold in the same region in plants showing flat stem, little leaf and witches’ broom symptoms, the present study confirms its occurrence also in the presence of virescence symptoms. This indicates the persistence and epidemiological stability in marigold of ‘Ca. P. asteris’ strains in eastern Uttar Pradesh region. The study also underscores the potential role of ornamental plants as reservoirs for phytoplasmas, contributing to disease persistence and spread in agro-ecosystems and emphasizing the need for continuous monitoring and integrated management strategies.

Brinjal little leaf disease, associated with the presence of phytoplasmas, is one of the most destructive diseases of brinjal in India, leading to considerable yield losses. The disease is predominantly associated with 16SrVI-D phytoplasmas throughout the Indian subcontinent, and reports of other phytoplasma subgroups remain sporadic and geographically limited. During comprehensive field surveys conducted in November 2025 in the Salegaon region near Pune, Maharashtra, characteristic little leaf symptoms were observed in brinjal cultivations with incidence ranging from 12% to 15%. Molecular detection using nested PCR targeting the 16S rRNA gene, followed by phylogenetic analysis, confirmed the presence of ‘Candidatus Phytoplasma trifolii’ belonging to the 16SrVI-A subgroup. Sequence analysis revealed 99.94% nucleotide identity with the reference strain (GenBank accession number AY390261). This represents the first report of ‘Ca. P. trifolii’ (16SrVI-A subgroup) in Maharashtra and constitutes the first westernmost geographic record of this subgroup presence in brinjal in India, extending its known distribution beyond Uttar Pradesh. The geographic expansion of this strain has important implications for disease management strategies, insect vector ecology, and regional surveillance programs. This finding highlights the genetic diversity within phytoplasma populations infecting brinjal in India and underscore the necessity for continuous molecular monitoring to track pathogen distribution and molecular diversity. The detection of 16SrVI-A subgroup in Maharashtra suggests potential pathogen dissemination through infected planting material or insect vector movement, necessitating enhanced quarantine measures and integrated disease management approaches for a sustainable brinjal production.

Phytoplasma, a phytopathogenic mollicute, poses a major threat to global agriculture with no effective control strategies currently available. Lantana camara L., an invasive weed, contains bioactive compounds with promising antimicrobial potential. This study investigates its potential, by utilizing the bioactive potential of green unripe berry extract from Lantana camara L., to mitigate phytoplasma infections in chili plants (Capsicum annuum). Phytoplasma infection in symptomatic chili plants was confirmed by nested PCR. Treatment with optimized L. camara extract led to significant recovery from little leaf disease. GC-MS analysis of Lantana camara L. green unripe berries identified six bioactive compounds with potential phytoplasma-inhibitory and antibacterial properties. To further explore their therapeutic potential, molecular docking studies were performed against the target protein SAP05 effector complexed with AtRpn10 (PDB ID: 8JTL) which is a known effector protein associated with phytoplasma pathogenicity. Among the docked compounds, Carsalam showed the strongest binding affinity (-7.2 kcal/mol) by interacting with Lys56 (C) residue. Other compounds like 5-(4-Chlorobenzyl)-1H-tetrazole and Cyclohexylmethylphosphonic acid also exhibited strong binding and targeted critical residues involved in protein function. These findings suggest L. camara has the potential to inhibit phytoplasma, marking a preliminary step toward sustainable phytoplasma management and an alternative to chemical treatments.

Medicinal plants include wide variety of wild and cultivated plant species that possess numerous biologically active compounds, referred to as phytochemicals. These plant-based phytochemicals play significant role in human and animal well-being. However, medicinal plants are susceptible to various biotic and abiotic stresses that negatively influence the composition of essential phytochemicals. Phytoplasmas characterized as cell-wall less bacterial pathogens cause diseases in medicinal plants belonging to over 70 families, mostly Apiaceae and Asteraceae throughout the world. Presence of phytoplasma induces changes in the amount and composition of secondary metabolites in infected plants that greatly affect the concentrations of valuable phytochemicals. The present review provides an outline of different medicinal plants associated with phytoplasma diseases in Eastern Uttar Pradesh belonging to ten families including Apiaceae, Cannabaceae, and Moringaceae.Among different phytoplasma groups, 16SrI is recorded as the most damaging phytoplasma group infecting Medicinal plants in Eastern Uttar Pradesh, India.