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Coscinium fenestratum is a medicinally significant critically endangered plant found in Western Ghats of India. The leaf spot and blight was observed in Kerala during 2021 with disease incidence of 40% in 20 assessed plants in 0.6 hectare. The associated fungus was isolated on potato dextrose agar medium. A total of six morpho-culturally identical isolates were isolated and morphologically identified. Based on morpho-cultural features, the fungus was identified at genus level as Lasiodiplodia sp. which was further authentically confirmed as Lasiodiplodia theobromae by molecular identification with a representative isolate (KFRIMCC 089) using multigene (ITS, LSU, SSU, TEF1 -α , and TUB2) sequence analysis and concatenated phylogenetic analysis (ITS-TEF1 -α -TUB2). Pathogenicity tests were also assessed in vitro and in vivo using mycelial disc and spore suspension of L. theobromae , and the isolated fungus's pathogenic behaviour was confirmed after re-isolation and morpho-cultural features. Literature survey reveals that there are no reports of L. theobromae on C. fenestratum from all over the world. Hence, C. fenestratum is being firstly reported as a new host record for L. theobromae from India. [ABSTRACT FROM AUTHOR]

Hydnocarpus longipedunculatus , a medically significant tree species, is threatened and has a narrow distribution, being endemic to the Southern Western Ghats of India. A case of fruit rot disease was observed in a solitary tree of H. longipedunculatus in the Kulamavu forest areas of Kerala, India. The causative fungus, Lasiodiplodia theobromae , was isolated and identified through a combination of morpho-cultural characteristics and molecular sequence analysis involving the internal transcribed spacer (ITS), partial translation elongation factor-1-α (TEF1-α), partial β-tubulin (TUB2), and large subunit ribosomal ribonucleic acid (LSU) regions. Additionally, concatenated multigene (ITS- TEF1-α-TUB2) phylogenetic analysis was done. Pathogenicity tests were conducted in vitro using mycelial disc methods and confirmed the pathogenic nature of the fungus through re-isolation and morphocultural analysis, satisfying Koch's postulates. Previous studies neither have reported H. longipedunculatus as a host for L. theobromae , nor has any genus within Hydnocarpus. Therefore, this represents the first documented instance of H. longipedunculatus as a novel host record for L. theobromae from India. [Display omitted] • Severe fruit rots disease was observed on H. longipedunculatus with 33 % disease incidence. • The causative agent was identified as Lasiodiplodia theobromae using integrative approaches. • This is the first record of Lasiodiplodia theobromae causing fruit rots on H. longipedunculatus from India. [ABSTRACT FROM AUTHOR]

Strychnos potatorum L.f., is a well-known medicinal plant found in peninsular India and Sri Lanka, which is widely used in traditional and modern medicines for curing various kinds of diseases. In January 2020, while conducting a foliar fungal disease investigation in Kerala, India, a leaf spot and blight disease was spotted on S. potatorum. The pathogen was isolated and identified as Curvularia verruculosa based on symptomatic studies, culture characteristics, conidial morphology, multigene (ITS- LSU-GAPDH-TEF1-α) molecular sequences analysis, and concatenate multigene (ITS- GAPDH-TEF1-α) phylogeny. Koch's postulates were evaluated in vitro , and similar symptoms and re-isolation of the pathogen confirmed the association of C. verruculosa with leaf spot and blight disease. To our knowledge, this is the first report of C. verruculosa causing foliar disease on S. potatorum in India. [Display omitted] • Strychnos potatorum , recently faces a novel biotic threat causing leaf spot and leaf blight. • The pathogen was identified as Curvularia verruculosa by morphology and molecular studies. • Precise identification of this foliar pathogen could be helpful for disease management. [ABSTRACT FROM AUTHOR]