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A new leaf blight disease in Schleichera oleosa seedlings was detected in a Kerala state forest nursery, India. Through morphological, cultural characterization, and multi-gene phylogenetic analysis, the fungal pathogen was identified as Pseudopestalotiopsis camelliae-sinensis, the first report on Schleichera in India. Koch's postulates were fulfilled. Research attention is required to manage emerging seedling diseases for quality planting materials. [ABSTRACT FROM AUTHOR]

Zinnia peruviana (Asteraceae) is an annual flowering plant cultivated in various gardens of Mysore, the south of Karnataka state, India. During 2021, phytoplasma‐like symptoms such as virescence and phyllody were observed on Zinnia in Mysore local gardens. A total of 10 symptomatic and five asymptomatic samples were collected, and the DNA was amplified by PCR using primers specific to 16S RNA and secA genes. The nucleotide sequence analysis showed that the 16S RNA and SecA gene sequences were most similar to those of 'Ca. P. aurantifolia', with identities greater than 99%. The phytoplasma sequence from this study shared a common clade with 'Ca. P. aurantifolia' when phylogenetic analysis was done. Similarly, the reference sequences for the 16S rRNA and SecA region confirmed the identity of the phytoplasma associated with the leaves of Zinnia. This is the new host record for 'Ca. P. aurantifolia' (16SrII‐D) phytoplasma associated with Z. peruviana from India. [ABSTRACT FROM AUTHOR]

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]

Linseed commonly called as flaxseed (Linum usitatissimum Linn.) is an important oilseed crop cultivated widely in Northern parts of Karnataka. During, 2019 (January–February), a characteristic disease was noticed with symptoms that resembled phytoplasma or like disease symptoms. The incidence was ranged from 6·5 to 16·5% in the experimental station of Raichur Agricultural University. The typical symptoms observed were virescence of floral parts, fasciation of the inflorescence axis, phyllody, stunted and flattened stem with reduced leaves. Symptomatic and healthy samples were collected and processed for molecular detection of phytoplasma. Total DNA was isolated from four infected plants and two healthy plants. The 16S rDNA region was amplified using P1/P7 followed by R16F2n/R16R2 primer pair which showed the amplification of expected amplicon size from all four infected samples. Furthermore, the SecA gene was amplified using SecA1/SecA3 primers. The PCR amplified products were subjected for direct sequencing from both directions and the consensus sequences were obtained and nBLAST search analysis revealed that the 16Sr RNA and SecA sequences were sharing maximum similarity (100%) with the reference sequence of Ca. P. cynodontis. The sequences were analysed phylogenetically by constructing a Phylogram independently by NJ method along with reference sequence of 16S rRNA region and SecA region retrieved from GenBank database showed that the phytoplasma sequence from linseed phyllody of the present study placed in a distinct clade along with reference sequence of "Ca. P. cynodontis" thus confirming the identity phylogenetically. Furthermore, iPhyClassifier and virtual RFLP proved that the phytoplasma belonged to 16SrXIV (subgroup A) phytoplasma. Previously linseed is known to be associated with 16SrII‐D phytoplasma but the association of the 16SrXIV‐A group of phytoplasma is not reported so far. Therefore, this is the new host record for Ca. P. cynodontis (16SrXIV‐A) phytoplasma associated with linseed stem fasciation, phyllody from India. [ABSTRACT FROM AUTHOR]

Cowpea is an important pulse crop cultivated in arid and semi‐arid regions of the world. During field survey, a characteristic wilt was observed in around 45 ha of cowpea fields with incidence 17–25%. Infection was seen in pre‐flowering stage and infected plants showed quick wilt symptoms with tan lesions near the stem–soil interface. Fungal pathogens associated were isolated on PDA, which produced dark to grey olivaceous colonies in the centre, and aerial mycelia were appressed with floccose and white to smoke‐grey. Conidia are aseptate, initially hyaline, smooth‐walled, broadly ellipsoidal with rounded ends becoming dark brown. Based on these morphological features, the fungal pathogen was identified as Aplosporella sp. The ITS‐rDNA region was amplified using ITS1/ITS4 primers and sequenced. The nBLAST and phylogenetic analysis confirmed the pathogen as Aplosporella hesperidica. The Koch's postulates were performed on 45‐days‐old cowpea plants with mycelial disc of A. hesperidica. Development of typical necrotic lesions was observed after 28 days of post‐inoculation and the pathogen's identity was confirmed based on re‐isolation. Efficacy of fungicides evaluated in vitro showed that the pathogen is highly sensitive to systemic fungicides rather than the contact fungicides. The cowpea production was severely affected owing to the causative agent A. hesperidica. The collar rot disease of cowpea by A. hesperidica is the first report in India. Significance and Impact of the Study: A new collar rot disease of cowpea recorded from India has been investigated. The necrotic lesions were enlarged and eventually quick wilt and death of the host plant was observed with incidence ranged from 17 to 25%. Associated fungal pathogen was isolated and identified as Aplosporella hesperidica based on morphology and ITS‐rDNA sequence analysis. Koch's postulates were performed under greenhouse conditions and in vitro evaluation of fungicides shows that the pathogen is sensitive to systemic fungicides. This is the first report of A. hesperidica causing collar rot disease of cowpea in India. Significance and Impact of the Study: A new collar rot disease of cowpea recorded from India has been investigated. The necrotic lesions were enlarged and eventually quick wilt and death of the host plant was observed with incidence ranged from 17 to 25%. Associated fungal pathogen was isolated and identified as Aplosporella hesperidica based on morphology and ITS‐rDNA sequence analysis. Koch's postulates were performed under greenhouse conditions and in vitro evaluation of fungicides shows that the pathogen is sensitive to systemic fungicides. This is the first report of A. hesperidica causing collar rot disease of cowpea in India. [ABSTRACT FROM AUTHOR]

Abstract Tuberose (Polianthes tuberosa) is an important commercial flower crop grown in Karnataka for its beautiful and fragrant cut flowers. Recently, an association of anthracnose disease (incidence ranged from 18 to 27%) characterized by the dark concentric sunken necrotic lesions with spore mass in the acervuli on leaves and peduncles of Tuberose was observed in a field survey conducted during October 2015 to March 2016. The pathogen was isolated on PDA medium. The fungal colony on PDA was grayish to dark gray. Conidia were falcate, one-celled, hyaline. Based on the micro-morphological, and cultural characteristics the pathogen was identified as Colletotrichum truncatum. The ITS-rDNA, GAPDH and ß-tubulin sequences of the pathogen were sequenced using ITS1/ITS4, GDF1/GDR1, T1/Bt2b primer pairs. nBLAST search and phylogenetic analysis confirmed that the pathogen was C. truncatum. Koch's postulates were conducted on 45-day-old tuberose plants by foliar application of conidial suspension of C. truncatum. Development of typical anthracnose disease was recorded after 18 days of post-inoculation and the pathogen's identity was confirmed by re-isolation and identification. The anthracnose disease associated with Tuberose is a major constraint for the production of quality cut flowers. This is the first report of C. truncatum causing anthracnose on Tuberose in India. Highlights • Phytopathological studies on anthracnose disease on leaves and peduncles of Tuberose have been investigated. • The pathogen has been isolated and identified by morpho-cultural characteristics. • Multi-locus sequence of ITS-rDNA, GAPDH & β-tubulin genes was employed for the identity of the fungal pathogen. • Pathogenicity tests were conducted to prove the association of the fungal pathogen with the anthracnose of Tuberose. • First report of Colletotrichum truncatum associated with the anthracnose disease on Tuberose in India. [ABSTRACT FROM AUTHOR]

Globe amaranth is an important floriculture plant grown for the cut flowers. The outbreak of southern blight disease was observed during 2019 in parts of the southern Karnataka. The disease incidence ranged from 9.54 to 21.13%. Disease symptoms include water-soaked lesions on the lower leaves, followed by quick wilting of the whole plant. The fungal pathogen was isolated on potato dextrose agar medium which produced white cottony mycelium with numerous reddish-brown sclerotia developed after 12 days of inoculation. A total of 12 fungal isolates were obtained from infected samples and their identity was established based on micro-morphological studies. Further, three isolates were used for molecular identification by sequencing the ITS-rDNA and tef-1α gene showed 100% sequence similarity with reference sequences. The associated fungal pathogen was identified as Athelia rolfsii. Further, pathogenicity tests were conducted on healthy plants in-vitro and in green house conditions. Typical foot rot disease symptoms were observed after 8 days of post-inoculation. The pathogen was re-isolated and its identity was confirmed. There are no reports of A. rolfsii on globe amaranth. To the best of our knowledge, this is the first report of A. rolfsii associated with southern blight disease of globe amaranth in India. [Display omitted] • A characteristic foot rot disease associated with Gomphrena globosa from India has been investigated. • The identity of Athelia rolfsii was done based on morphological and molecular identification (ITS & TEF-1 α gene) and phylogenetic analysis. • Pathogenicity test conducted and proved the association of isolated pathogen as causal agent. • First report of A. rolfsii associated with foot rot disease of Gomphrena globosa from India. [ABSTRACT FROM AUTHOR]

The multi-use tree Canthium dicoccum (Rubiaceae) growing in shrub forests of Mysore, Mandya and Chamarajanagar (India) was severely affected by a leaf blight disease. The ascomycete Pestalotiopsis mangiferae was consistently isolated from symptomatic leaves and identified by micromorphology and ITS rDNA sequencing analysis. Pathogenicity test was performed and Koch's postulates were fulfilled. This is the first report of P. mangiferae causing leaf blight of C. dicoccum in India. [ABSTRACT FROM AUTHOR]

An abstract of the article "First Report of Pestalotiopsis Species Causing Leaf Spot of Cowpea (Vigna unguiculata" by S. Mahadevakumar and G. R. Janardhana is presented.

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]

During recent survey for the investigation of foliar fungi in Kerala, India, a new species of foliicolous hyphomycete, Paramyrothecium kamalii was discovered on living leaves of Matourea azurea (Plantaginaceae) based on morpho-cultural characteristics and multigene (ITS, LSU, cmdA, tub2, and rpb2) phylogenetic analysis; is described, illustrated and discussed. In vitro Pathogenicity tests were performed and confirmed the pathogenic nature of the fungus, thereby fulfilling Koch's postulates. Phylogenetically, P. kamalii forms a distinct clade, closely related to P. verroridum, P. indicum, and P. roridum. However, it differs morphologically by having longer conidiophores and conidia and lacks setae, unlike the closer species. The identification of P. kamalii as a new foliar pathogen provides critical insights for surveillance and effective control measure of this foliar disease of M. azurea in tropical ecosystems., Competing Interests: Declarations. Disclosure statement: The authors declare that they have no conflict of interest to develop this research work. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sapota is an important horticultural crop grown in India, and Karnataka is a major producer of sapota. A characteristic leaf blight disease was observed in Southern Karnataka during field surveys conducted in 2019 with an incidence of 13-22% in approximately 45 ha of sapota field. The leaf blight-associated pathogen was isolated on the potato dextrose agar medium. A total of 12 isolates obtained from each location were identified culturally and morphologically. Based on the morphological and cultural features, the pathogen was identified as Pestalotiopsis or Neopestalotiopsis, which was further confirmed by molecular identification using a representative isolate (MZ03). The ITS rDNA and β-tubulin genes were amplified and sequenced using ITS1/ITS4 and T1/T22 primer pairs respectively. nBLAST search analysis and concatenated (ITS-rDNA and TUB2 loci) phylogenetic analysis confirmed the pathogen identity as Neopestalotiopsis vitis. Pathogenicity tests conducted on detached leaves by inoculation with a conidial suspension of N. vitis produced typical blight symptoms after 4-5 days and progressed to cover the entire leaf lamina after 10-12 days. The pathogen's identity was confirmed after re-isolation by cultural and morphological features. Although Pestalotiopsis clavispora and Pestalotiopsis versicolor causing diseases on sapota seedlings and trees have been reported, no reports are available for the occurrence of N. vitis to sapota from India. This is the first report of N. vitis associated with leaf blight disease of sapota from India., (© 2021 The Society for Applied Microbiology.)

Cowpea is an important pulse crop extensively grown in arid and semi-arid tropics which is affected by a number of diseases. Fungi belonging to mycelia sterilia are known to cause many diseases on cereals and pulses. During the cowpea field survey in Mysore District of Karnataka (India), Dactuliophora sp. was identified as the major pathogen causing zonate leaf spot (ZLS) disease. The fungal pathogen was isolated from naturally infected cowpea leaves and identified as a member belongs to the genus Dactuliophora, which was previously described by CLA Leakey in the year 1964 on Vigna unguiculata from Africa. However, detailed morphological and cultural examinations of the pathogen revealed striking differences from that of D. tarrii. Based on differences in morphology with D. tarrii, a new species Dactuliophora mysorensis sp. nov. is described herein. The disease incidence as well as disease index was estimated for 3 years (2016-2018). The severity of the disease was high during August-November. High incidence and disease index of ZLS was recorded in Doddamaragowdanahally region. The pathogenicity tests demonstrated similar symptoms of ZLS. The ITS barcoding revealed that the pathogen is closely related to Rhizoctonia bataticola and Macrophomina phaseolina. Further, in vitro evaluation of fungicides was carried out by poisoned food technique. Among the five fungicides examined, only two systemic fungicides (Benomyl and Carbendazim) were effective against D. mysorensis. Thus, the present study recommends Benomyl and Carbendazim for management of ZLS disease caused by D. mysorensis.