First report of Candidatus Phytoplasma australasia (16SrII- subgroup D) associated with virescence of Chia (Salvia hispanica L.) from India.

Chia (Salvia hispanica L., Lamiaceae) is an important commercial and medicinal crop recently popularized in India and widely cultivated in Karnataka (Joy et al., 2022). During the field survey of chia crop diseases, characteristic virescence like symptoms were observed at Main Agricultural Research Station, UAS, Raichur as well as at Mysuru and HD Kote region. The incidence was ranged from 2 - 4 per cent in an area of 30 hectares. Typical symptoms associated with chia are malformed shoot and/or inflorescence axis with reduced floral parts with greenish florets. The stem axis become thick, flattened, leaves are reduced towards terminal region. A total of five phytoplasma suspected samples and five suspected healthy samples were used for identification purpose. The Plant Genomic DNA Miniprep Kit (Sigma Aldrich, USA) was used to extract the DNA from five symptomatic and five asymptomatic samples and the DNA was used as template to amplify the phytoplasma-specific 16S rDNA gene using P1/P7 primers (Deng and Hiruki, 1991; Schneider et al., 1995) followed by nested PCR using R16F2n/R16R2 primers (Gundersen and Lee 1996). The expected 1.25-kb amplicon was detected from the suspected symptomatic samples. Nested PCR products were purified and sequenced from both the directions using ABIX370 Genetic Analyzer (Applied Biosystems, Waltham, MA). The analysis revealed that all five sequences shared 100 per cent identity with Candidatus Phytoplasma aurantifolia (OM649850, ON975012) and Tomato big bud phytoplasma (EF193359). The in-silico RFLP pattern of F2n/R2 primed region of 16S rDNA gene analyzed by using iPhyClassifier (Zhao et al. 2009) revealed that the sequence shared 98.72 per cent nucleotide sequence similarity with coefficient value of 1.00 to the reference strain RFLP pattern of 16Sr group II, subgroup D (witches'-broom disease of lime; U15442). Based on 16SrDNA sequences and in-silico RFLP analysis, the phytoplasma associated with the chia virescence was identified as a member of 16SrII-D group. Further, SecA gene was also amplified from the samples using SecAfor1/SecArev3 primer pair (Hodgetts et al., 2008). All samples produced ~400 bp products and sequenced as detailed above. Sequence analysis by nBLAST revealed 100 per cent similarity to Ca. P. australasia (MW020545) and Ca. P. aurantifolia isolate Idukki Kerala 1 (MK726369) both representing 16SrII-D group phytoplasma. The representative sequence (16Sr: PP359693, PP359694; secA:PP386558, PP386559) were deposited in GenBank. Chia virescence phytoplasma belonging to Ca. phytoplasma australasia has not been reported anywhere. The phytopathological studies associated with chia crop are very limited. Joy et al. (2022) reported the occurrence of foot rot disease caused by Athelia rolfsii. Several hosts are recorded to be associated with 16SrII D phytoplasma which includes china aster, eggplant and crotalaria (Mahadevakumar et al., 2017, Yadav et al., 2016a, b). Now the wide occurrence of the phytoplasma in the area might have transmitted by vectors. The occurrence of virescence is of great importance as it affects the overall yield which reduces the market value. To our knowledge, this is the first report of a group 16SrII-D phytoplasma associated with chia virescence in India.

First report of Neopestalotiopsis clavispora causing cashew leaf blight disease in India.

Cashew (Anacardium occidentale) is an important commercial crop and highly prone to many biotic and abiotic stress. During March 2021, severe leaf blight symptoms were observed in Priyanka variety with 25-30% incidence grown under greenhouse nursery at ICAR-Directorate of Cashew Research (ICAR-DCR), Puttur (12º74'08.92"N; 75º22'97.22"E), Karnataka. Initial symptoms include small, irregular necrotic spots and later, the spots enlarged and covered major portion of the leaf lamina. In severe infection, leaves exhibited coalescing of spots leading to blight appearance. The infected leaves were randomly collected (n=5) and surface sterilized with 1% sodium hypochlorite for 1 min followed by three washes in sterile distilled water (SDW). Samples were plated on PDA plates amended with Rifampicin (40 mg/L) and kept for incubation at 25±2 oC for 5 days (12/12 h dark light period). A white-greyish, aerial, cottony mycelium on upper side with light yellow colour on the reverse side was consistently isolated. The black viscous acervuli were observed after 10-12 days of incubation. The conidia were fusiform, five-celled, versicoloured with three olivaceous brown median cells, two terminal hyaline cells, measured 23.3±2.12 - 28.33±2.7 x 3.6±0.8 - 4.28±0.78 µm (n=30). The apical cells had two to three flexuous, unbranched appendages, and basal appendage was solitary, tubular and unbranched. Morphological and cultural characteristics confirmed the pathogen as Neopestalotiopsis sp. (Maharachchikumbura et al. 2012). Further, two representative isolates (CLB_SCN1 & CLB_SCN2) were subjected for molecular characterization selected for molecular identification based on ITS-rDNA, tef-1α and tub2 gene sequences and phylogenetic analysis. Genomic DNA was isolated from 15 days old cultures and internal transcribed spacer (ITS) of ribosomal DNA (rDNA) (White et al. 1990), translation elongation factor 1α (tef-1α) gene (O'Donnell et al. 1998) and beta tubulin (tub2) using ITS1/ITS4, TEF1/TEF2 and Bt2a/Bt2b (Carbone and Kohn 1999; Glass and Donaldson 1995) were amplified using primer pairs respectively. PCR amplicons were sequenced, and the sequences were deposited in GenBank (accession numbers: ITS: OP880881.1, OP880882.1; tef-1α: OP882579.1, OP882580.1; and tub2: OP882581., OP882582.1). The phylogeny was constructed based on combined ITS, tef-1a, and tub2 regions. Neighbour-Joining (NJ) analysis was conducted and the tree was constructed with the substitution models (branch support was evaluated by 1,000 bootstrap replications). Combined phylogeny confirmed that the sequences shared a common clade with N. clavispora. Hence, morphological, microscopic and molecular characterization confirmed the pathogen as N. clavispora. The pathogenicity test was done on six months old healthy grafts of Priyanka variety (n=9) and repeated thrice. Conidial suspension (2×106 spores/ml) of N. clavispora CLB_SCN1 (15 days old culture) was sprayed on the healthy cashew seedlings, and kept in greenhouse by covering with polythene bags for 24 h (>80 % RH) and maintained under greenhouse condition. The control grafts were inoculated with SDW. The inoculated plants showed blight symptoms after 7-10-day post inoculation and control remained heathy. Re-isolation was done from the symptomatic leaves and identity was confirmed using cultural and molecular studies. Earlier reports showed that, N. clavispora has been reported to cause cardamom leaf blight (Biju et al 2018) and leaf spot disease of plum (Banerjee and Rana 2020). To best of our knowledge, this is the first report of cashew leaf blight disease caused by N. clavispora from India (Farr and Rossman, 2022). Early detection will help farmer in better management and avoiding economic loss caused by N. clavispora.

Morphological and molecular characterization of Lasiodiplodia theobromae associated with leaf spot and blight disease of Coscinium fenestratum (Gaertn.) Colebr.-a new host record from India.

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.

Fungal Planet description sheets: 1478-1549.

Novel species of fungi described in this study include those from various countries as follows: Australia, Aschersonia mackerrasiae on whitefly, Cladosporium corticola on bark of Melaleuca quinquenervia, Penicillium nudgee from soil under Melaleuca quinquenervia, Pseudocercospora blackwoodiae on leaf spot of Persoonia falcata, and Pseudocercospora dalyelliae on leaf spot of Senna alata. Bolivia, Aspicilia lutzoniana on fully submersed siliceous schist in high-mountain streams, and Niesslia parviseta on the lower part and apothecial discs of Erioderma barbellatum on a twig. Brazil, Cyathus bonsai on decaying wood, Geastrum albofibrosum from moist soil with leaf litter, Laetiporus pratigiensis on a trunk of a living unknown hardwood tree species, and Scytalidium synnematicum on dead twigs of unidentified plant. Bulgaria, Amanita abscondita on sandy soil in a plantation of Quercus suber. Canada, Penicillium acericola on dead bark of Acer saccharum, and Penicillium corticola on dead bark of Acer saccharum. China, Colletotrichum qingyuanense on fruit lesion of Capsicum annuum. Denmark, Helminthosphaeria leptospora on corticioid Neohypochnicium cremicolor. Ecuador (Galapagos), Phaeosphaeria scalesiae on Scalesia sp. Finland, Inocybe jacobssonii on calcareous soils in dry forests and park habitats. France, Cortinarius rufomyrrheus on sandy soil under Pinus pinaster, and Periconia neominutissima on leaves of Poaceae. India, Coprinopsis fragilis on decaying bark of logs, Filoboletus keralensis on unidentified woody substrate, Penicillium sankaranii from soil, Physisporinus tamilnaduensis on the trunk of Azadirachta indica, and Poronia nagaraholensis on elephant dung. Iran, Neosetophoma fici on infected leaves of Ficus elastica. Israel, Cnidariophoma eilatica (incl. Cnidariophoma gen. nov.) from Stylophora pistillata. Italy, Lyophyllum obscurum on acidic soil. Namibia, Aureobasidium faidherbiae on dead leaf of Faidherbia albida, and Aureobasidium welwitschiae on dead leaves of Welwitschia mirabilis. Netherlands, Gaeumannomycella caricigena on dead culms of Carex elongata, Houtenomyces caricicola (incl. Houtenomyces gen. nov.) on culms of Carex disticha, Neodacampia ulmea (incl. Neodacampia gen. nov.) on branch of Ulmus laevis, Niesslia phragmiticola on dead standing culms of Phragmites australis, Pseudopyricularia caricicola on culms of Carex disticha, and Rhodoveronaea nieuwwulvenica on dead bamboo sticks. Norway, Arrhenia similis half-buried and moss-covered pieces of rotting wood in grass-grown path. Pakistan, Mallocybe ahmadii on soil. Poland, Beskidomyces laricis (incl. Beskidomyces gen. nov.) from resin of Larix decidua ssp. polonica, Lapidomyces epipinicola from sooty mould community on Pinus nigra, and Leptographium granulatum from a gallery of Dendroctonus micans on Picea abies. Portugal, Geoglossum azoricum on mossy areas of laurel forest areas planted with Cryptomeria japonica, and Lunasporangiospora lusitanica from a biofilm covering a biodeteriorated limestone wall. Qatar, Alternaria halotolerans from hypersaline sea water, and Alternaria qatarensis from water sample collected from hypersaline lagoon. South Africa, Alfaria thamnochorti on culm of Thamnochortus fraternus, Knufia aloeicola on Aloe gariepensis, Muriseptatomyces restionacearum (incl. Muriseptatomyces gen. nov.) on culms of Restionaceae, Neocladosporium arctotis on nest of cases of bag worm moths (Lepidoptera, Psychidae) on Arctotis auriculata, Neodevriesia scadoxi on leaves of Scadoxus puniceus, Paraloratospora schoenoplecti on stems of Schoenoplectus lacustris, Tulasnella epidendrea from the roots of Epidendrum × obrienianum, and Xenoidriella cinnamomi (incl. Xenoidriella gen. nov.) on leaf of Cinnamomum camphora. South Korea, Lemonniera fraxinea on decaying leaves of Fraxinus sp. from pond. Spain, Atheniella lauri on the bark of fallen trees of Laurus nobilis, Halocryptovalsa endophytica from surface-sterilised, asymptomatic roots of Salicornia patula, Inocybe amygdaliolens on soil in mixed forest, Inocybe pityusarum on calcareous soil in mixed forest, Inocybe roseobulbipes on acidic soils, Neonectria borealis from roots of Vitis berlandieri × Vitis rupestris, Sympoventuria eucalyptorum on leaves of Eucalyptus sp., and Tuber conchae from soil. Sweden, Inocybe bidumensis on calcareous soil. Thailand, Cordyceps sandindaengensis on Lepidoptera pupa, buried in soil, Ophiocordyceps kuchinaraiensis on Coleoptera larva, buried in soil, and Samsoniella winandae on Lepidoptera pupa, buried in soil. Taiwan region (China), Neophaeosphaeria livistonae on dead leaf of Livistona rotundifolia. Türkiye, Melanogaster anatolicus on clay loamy soils. UK, Basingstokeomyces allii (incl. Basingstokeomyces gen. nov.) on leaves of Allium schoenoprasum. Ukraine, Xenosphaeropsis corni on recently dead stem of Cornus alba. USA, Nothotrichosporon aquaticum (incl. Nothotrichosporon gen. nov.) from water, and Periconia philadelphiana from swab of coil surface. Morphological and culture characteristics for these new taxa are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Shivas RG, et al. 2023. Fungal Planet description sheets: 1478-1549. Persoonia 50: 158- 310. https://doi.org/10.3767/persoonia.2023.50.05.

Fungal Planet description sheets: 1550-1613.

Novel species of fungi described in this study include those from various countries as follows: Argentina, Neocamarosporium halophilum in leaf spots of Atriplex undulata. Australia, Aschersonia merianiae on scale insect (Coccoidea), Curvularia huamulaniae isolated from air, Hevansia mainiae on dead spider, Ophiocordyceps poecilometigena on Poecilometis sp. Bolivia, Lecanora menthoides on sandstone, in open semi-desert montane areas, Sticta monlueckiorum corticolous in a forest, Trichonectria epimegalosporae on apothecia of corticolous Megalospora sulphurata var. sulphurata, Trichonectria puncteliae on the thallus of Punctelia borreri. Brazil, Catenomargarita pseudocercosporicola (incl. Catenomargarita gen. nov.) hyperparasitic on Pseudocercospora fijiensis on leaves of Musa acuminata, Tulasnella restingae on protocorms and roots of Epidendrum fulgens. Bulgaria, Anthracoidea umbrosae on Carex spp. Croatia, Hymenoscyphus radicis from surface-sterilised, asymptomatic roots of Microthlaspi erraticum, Orbilia multiserpentina on wood of decorticated branches of Quercus pubescens. France, Calosporella punctatispora on dead corticated twigs of Aceropalus. French West Indies (Martinique), Eutypella lechatii on dead corticated palm stem. Germany, Arrhenia alcalinophila on loamy soil. Iceland, Cistella blauvikensis on dead grass (Poaceae). India, Fulvifomes maritimus on living Peltophorum pterocarpum, Fulvifomes natarajanii on dead wood of Prosopis juliflora, Fulvifomes subazonatus on trunk of Azadirachta indica, Macrolepiota bharadwajii on moist soil near the forest, Narcissea delicata on decaying elephant dung, Paramyrothecium indicum on living leaves of Hibiscus hispidissimus, Trichoglossum syamviswanathii on moist soil near the base of a bamboo plantation. Iran, Vacuiphoma astragalicola from stem canker of Astragalus sarcocolla. Malaysia, Neoeriomycopsis fissistigmae (incl. Neoeriomycopsidaceae fam. nov.) on leaf spots on flower Fissistigma sp. Namibia, Exophiala lichenicola lichenicolous on Acarospora cf. luederitzensis. Netherlands, Entoloma occultatum on soil, Extremus caricis on dead leaves of Carex sp., Inocybe pseudomytiliodora on loamy soil. Norway, Inocybe guldeniae on calcareous soil, Inocybe rupestroides on gravelly soil. Pakistan, Hymenagaricus brunneodiscus on soil. Philippines, Ophiocordyceps philippinensis parasitic on Asilus sp. Poland, Hawksworthiomyces ciconiae isolated from Ciconia ciconia nest, Plectosphaerella vigrensis from leaf spots on Impatiens noli-tangere, Xenoramularia epitaxicola from sooty mould community on Taxus baccata. Portugal, Inocybe dagamae on clay soil. Saudi Arabia, Diaporthe jazanensis on branches of Coffea arabica. South Africa, Alternaria moraeae on dead leaves of Moraea sp., Bonitomyces buffels-kloofinus (incl. Bonitomyces gen. nov.) on dead twigs of unknown tree, Constrictochalara koukolii on living leaves of Itea rhamnoides colonised by a Meliola sp., Cylindromonium lichenophilum on Parmelina tiliacea, Gamszarella buffelskloofina (incl. Gamszarella gen. nov.) on dead insect, Isthmosporiella africana (incl. Isthmosporiella gen. nov.) on dead twigs of unknown tree, Nothoeucasphaeria buffelskloofina (incl. Nothoeucasphaeria gen. nov.), on dead twigs of unknown tree, Nothomicrothyrium beaucarneae (incl. Nothomicrothyrium gen. nov.) on dead leaves of Beaucarnea stricta, Paramycosphaerella proteae on living leaves of Protea caffra, Querciphoma foliicola on leaf litter, Rachicladosporium conostomii on dead twigs of Conostomium natalense var. glabrum, Rhamphoriopsis synnematosa on dead twig of unknown tree, Waltergamsia mpumalanga on dead leaves of unknown tree. Spain, Amanita fulvogrisea on limestone soil, in mixed forest, Amanita herculis in open Quercus forest, Vuilleminia beltraniae on Cistus symphytifolius. Sweden, Pachyella pulchella on decaying wood on sand-silt riverbank. Thailand, Deniquelata cassiae on dead stem of Cassia fistula, Stomiopeltis thailandica on dead twigs of Magnolia champaca. Ukraine, Circinaria podoliana on natural limestone outcrops, Neonematogonum carpinicola (incl. Neonematogonum gen. nov.) on dead branches of Carpinus betulus. USA, Exophiala wilsonii water from cooling tower, Hygrophorus aesculeticola on soil in mixed forest, and Neocelosporium aereum from air in a house attic. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Costa MM, Kandemir H, et al. 2023. Fungal Planet description sheets: 1550-1613. Persoonia 51: 280-417. doi: 10.3767/persoonia.2023.51.08.

First report of Nigrospora sphaerica associated with leaf spot disease of Crossandra infundibuliformis in India.

Crossandra (Crossandra infundubuliformis (L.) Nees.) is one of the main floriculture crops in Karnataka. In 2020 (March-June), a characteristic leaf spot disease of unknown etiology with an incidence ranging from 10-12% (~30 ha area evaluated) was observed in Southern Karnataka (Mysore, Mandya). Initially, the symptoms developed as small specks (3 to 8 mm), characterized by circular to irregular shapes in the beginning and coalesced to form larger lesions. Ten samples were collected in polybags followed by the isolation of associated fungal pathogen on potato dextrose agar (PDA) medium amended with Chloramphenicol (60 mg/L). Briefly, small pieces of infected leaves were cut into small pieces and surface sterilized with 2% sodium hypochlorite (NaOCl) solution, rinsed three times with sterile distilled water (SDW), blot dried, then inoculated onto PDA medium, and incubated at room temperature (27 ± 2°C) for 3 - 5 days. Fungal colonies developed from the segments and were subcultured through hyphal tipping to fresh PDA plates to get pure cultures. A total of 12 pure cultures were obtained. Mycelia were initially white and eventually turned gray. The conidia were black, single-celled, smooth, spherical to subspherical, 9 to 18 µm in diameter (n=50), and borne singly on a hyaline vesicle at the tip of each conidiophore. The identity was initially established based on the cultural features and conidial morphology as Nigrospora sp. (Deepika et al., 2021). To confirm the identity of fungal isolates based on molecular sequence analysis was performed for two representative isolates (CIT1 & CIT2). ITS-rDNA, tub2 & EF-1α gene were amplified using primers ITS1/ITS4, T1/T22 & EF1-728F/986R (White et al., 1990; O'Donnel and Cigelnik, 1997; Carbone and Kohn, 1999), then purified and sequenced. The BLASTn analysis of ITS, tub2 and EF-1α gene showed 99-100% similarity with reference sequences from the GenBank database to Nigrospora sphaerica (ITS: 520bp, KX985935 - LC7312; MH854878 - CBS:166.26; tub2: 357bp, MZ032030 - WYR007, 350bp, KY019606 - LC7298, KY019522 - LC4278, KY019520 - LC4274; EF-1α: 472bp, KY019397 - LC7294, KY019331 - LC4241; MN864137 - HN-BH-3) and the sequences were deposited in GenBank (ITS: OL672271 & OL672272; tub2: OL782120 & OL782121; EF-1α: ON051604 & ON051605) (Wang et al., 2017). The associated fungal pathogen was identified as N. sphaerica (Sacc.) Mason (Chen et al. 2018; Deepika et al., 2021) based on the cultural, morphological, microscopic, and molecular characteristics. Further, pathogenicity tests were conducted on healthy plants (Crossandra cv. Arka; n=30) grown under greenhouse conditions (28±2 °C; 80% RH). Inoculations were made with conidial suspension (18 days old N. sphaerica isolate CIT1, 106 conidia/ml) prepared in SDW, and healthy plants sprayed with SDW (n=10) served as controls. All the plants were covered with polyethylene bags for 24-48 hr and observations were made at regular intervals. Typical necrotic lesions developed on 16 plants after 12 days after inoculation but no symptoms were observed on the control plants. The associated pathogen was re-isolated from diseased leaves and confirmed their identity based on morphology and cultural characteristics. Earlier, N. sphaerica was associated with various tree species as an endophyte, and recently several reports have appeared to cause disease on various crop plants (Deepika et al., 2021). However, there are no previous reports on the association of N. sphaerica causing leaf spot disease on C. infundibuliformis from India. Early diagnosis of this leaf spot disease will help the floriculturist adopt suitable management practices to avoid significant economic loss.

First report of Athelia rolfsii (=Sclerotium rolfsii) associated with foot rot disease of Chrysanthemum morifolium in India.

Chrysanthemum morifolium L. is an important flower crop grown in different parts of Karnataka for its striking cut flowers and international market value. During a field survey (Mysore district, Karnataka, February, 2022), chrysanthemum fields were found infected with foot rot disease. The presence of white mycelial structures with sclerotia were recorded near the stem-soil interface. The disease incidence ranged 10-12% measured in an area of approximately 10 hectares. The infected plants showed quick wilt, yellowing and toppling of the entire plant. Infected plants from Doddamaragowdanahally and Rayanahally (n=15) were collected and associated fungal pathogen isolated after surface sterilization with NaOCl (1%) on potato dextrose agar (PDA) amended with chloramphenicol (50 mg/L). Fungal mycelia developed from the infected tissues were inoculated on to fresh PDA plates to obtained pure cultures for further identification. Fungal colonies with dense, aerial whitish-cottony mycelia with uniformly globoid sclerotia (0.284.2 mm) were observed after 15 days of incubation (28 ± 2°C). Sclerotia were white in the beginning and turned brown at maturity. The average number of sclerotia produced per plate ranged from 240 to >480 (n = 10). To further to confirm the identity of the isolates, two representative isolates (CmSr1 and CmSr2) was subjected to molecular identification based on ITS-rDNA sequences. Briefly, genomic DNA was isolated from 12 day old cultures using the CTAB method and ITS-rDNA was amplified using ITS1-ITS4 primers (White et al., 1990). An expected amplicon of >650 bp (ITS) was obtained and later sequenced from both the directions. The consensus sequences were analysed through nBLAST search which revealed that 100% sequence similarity with reference sequences of Athelia rolfsii (S. rolfsii) from GenBank database (MT127465, MN974137, KC292637; identity 656/656; 0 gaps). A phylogenetic tree obtained by the neighbor-joining method using MEGAX shared a common clade with the reference sequences retrieved and computed, thus confirming the identification based on sequence analysis and molecular phylogeny. The representative sequence of A. rolfsii isolates CmSr1 and CmSr2 isolates deposited in GenBank with Accession nos. ON456153 and ON456154, respectively. Based on etiology, morphological, cultural and molecular data the pathogen was identified as Athelia rolfsii (Curzi) Tu & Kimbrough (Syn: Sclerotium rolfsii Sacc.) (Mordue, 1974; Mahadevakumar et al., 2016, 2018). Plants (n=60) were inoculated with sclerotial bodies (2 sclerotia/plant) near stem soil interface under green house and covered with polythene bags (at 27 ± 2°C and 80% RH). Non-inoculated plants (n=20) served as controls. The development of foot rot disease was observed eight days after inoculation. A total of 48 plants showed the foot rot symptoms and 12 inoculated plants and control plants remained healthy. The identity of the fungus was confirmed by morphological and cultural characters after re-isolation. C. morifolium is an important flower crop in Karnataka. S. rolfsii is known to be associated with blight and collar rot of Chrysanthemum spp. from Kerala (Beena et al., 2002) but no species (host) identity provided. Therefore, to the best of our knowledge, this is the first report of foot rot disease caused by Athelia rolfsii on C. morifolium in India. Early diagnosis of this disease will help the farmers to adopt suitable management practices to avoid loss.

First report of Lasiodiplodia theobromae associated with panicle blight of grapes (Vitis vinifera L.) in India.

Grape (Vitis vinefera L.) is a popular horticulture crop in Karnataka, India. A fungal pathogen caused panicle blight on panicles with immature fruit and severity increased subsequently in the grape growing regions of Devanahalli and Doddaballapur, Karnataka, between August and September 2019. The disease incidence varied from 15 to 18 percent in around 45 hectares of grape vineyards surveyed. The associated fungal pathogen was isolated on Potato Dextrose Agar (PDA) medium (HiMedia Laboratory, Mumbai, India) amended with Chloramphenicol. A total of 12 fungal isolates were obtained and identified based on morphology. Fungal cultures obtained from all the panicle blight affected samples were fluffy grayish to black with profuse, dense mycelium. Microscopic examinations revealed that the conidia ellipsoidal, two celled and hyaline when young, and developed dark brown pigments at maturity. Mature conidia measured 18.24±2.35 to 26.62±3.11 µm long and 10.32±1.08 to 12.57±1.82 µm width (n=30). The fungal pathogen was identified as a Lasiodiplodia sp. based on colony morphology and microscopic features. A total of three representative isolates L. theobromae (Vv12, Vv15, and Vv19) were selected for molecular identification based on ITS-rDNA, tub2 and EF-1α gene sequences and phylogenetic analysis. Genomic DNA was isolated from 12 day old cultures and ITS-rDNA, tub2 and EF-1α genes were amplified using ITS1/ITS4; Bt2a/Bt2b and EF1-728F/986R primer pairs, respectively (White et al., 1990; Glass and Donaldson, 1995, Carbone and Kohn, 1999). PCR amplicons were sequenced and the sequences were deposited in GenBank with the accession number ITS: MZ855866.1; MZ855867.1; MZ855868.1; tub2: MZ868708.1; MZ868709.1; MZ868710.1 and EF-1α: OM604750; OM604751; OM604752 respectively. The phylogeny was constructed based on combined ITS, EF-1α and the tub2 regions. Maximum Likelihood (ML) analysis was conducted and an ML tree was constructed with the substitution models (branch support was evaluated by 1,000 bootstrap replications). Combined phylogeny confirmed that the sequences shared a common clade with L. theobromae. Based on micro-morphological features and multi-locus sequence phylogeny, the associated fungal pathogen was identified as L. theobromae. There are no reports on the occurrence of L. theobromae causing panicle blight on grapes from India. Further, the pathogens association was confirmed through pathogenicity assay conducted on field harvested healthy bunches of grapes maintained under humid chamber. A total of 10 grape bunches were inoculated with a mycelial disc on the rachis of the panicle and incubated in a moist chamber for 5 days and control sets were inoculated with only agar plugs. The experiments were conducted in three replicates and repeated twice. A total of 21 panicle bunches developed typical rot symptoms 12-days post inoculation. The identity of the pathogen was confirmed based on micromorphology and cultural features after re-isolation (n=5), thus proving the Koch postulates and confirming the association of L. theobromae with panicle blight of grapes. Lasiodiplodia species are known to cause dieback, stem blight, leaf blights and spots on various crop plants. Mathur (1979) mentioned the occurrence of L. theobromae on grapes, however, no further details are available on the part associated, as well as morphological and molecular confirmation of L. theobromae. This is the first report of the L. theobromae causing panicle blight disease of grapes in India. Further, understanding the host range for L. theobromae and its variation will help to draw suitable disease management strategies.

First Report of Powdery Mildew Caused by Erysiphe diffusa on Cluster Bean in India.

Cluster bean (Cyamopsis tetragonoloba (L.) Taub.) is an important vegetable crop cultivated widely in India. During a field survey in November 2021, about 60% of plants exhibited characteristic powdery mildew disease symptoms and signs in a 15 ha field in Northern Karnataka (Raichur), India. Initially, the symptoms and signs appeared as tan lesions, which later became small, circular and chlorotic. The abaxial surface turned yellow and was covered with white mycelial growth. As the disease progressed, white mycelia grew on the adaxial leaf surface, stems and pods as well. In severe infections, drying and premature defoliation of infected leaves were observed. Infected leaf samples with mycelia were collected (n=8) and the fungus was subjected to morphological and molecular observations. Mycelia on leaves was characterized as epiphytic, amphigenous, producing dense, white patches on the upper and lower leaf surfaces, stem and young pods. Hyphae were hyaline, thin-walled, 1.8 to 4.2 µm wide with erect conidiophores consisting of a cylindrical foot-cell, straight flexuous at the base and measured 20 to 36 × 6 to 9 µm (n=30), followed by 1 to 2 shorter cells. Ellipsoid conidia were produced singly and measured 28 to 42 × 12 to 20 µm (n=30) without fibrosin bodies. Chasmothecia were not observed. A reference specimen was deposited at the Institution of Excellence, University of Mysore Herbarium (UOM-IOE 2022_1). The morphology and other characteristics of conidia were consistent with an Erysiphe species (Braun and Cook 2012). Genomic DNA was isolated from a conidial suspension harvested from the powdery mildew affected cluster bean samples. The ITS region was amplified from three samples using powdery mildew-specific primer pair PN23/PN34 and sequenced directly (Chen et al. 2008). nBLAST analysis revealed that the ITS sequence shared 100% similarity with the reference sequence (E. diffusa vouchers HMJAU02177 - KM260363, BRIP 71013 - MW009058) of Erysiphe diffusa (Cooke & Peck) U. Braun & S. Takam. In addition to 100% match to voucher specimens of E. diffusa, there were no vouchers from other species that also had 100% match. The representative sequences were deposited in GenBank with accession numbers OM669776 - OM669778. Koch's postulates were conducted on healthy cluster bean plants grown under greenhouse conditions. Conidia were harvested from infected leaves, suspended in water and sprayed on 40 to 50-day-old cluster bean plants (28 ± 2°C and >70% relative humidity). The development of powdery mildew symptoms was recorded on 22 plants after 10-14 days of post inoculation. Control plants inoculated with sterile water remained healthy without powdery mildew symptoms. Microscopic observation of spores from inoculated plants confirmed the pathogen as E. diffusa. The genus Erysiphe is known to infect many crop plants. E. diffusa has been reported to infect Vigna radiata, Glycine max and Phaseolus mungo in Australia (Kelly et al. 2021). No reports are available at USDA's host-fungus database for cluster bean and E. diffusa (Farr and Rossman 2022). To the best of our knowledge, this is the first report of E. diffusa associated with powdery mildew of cluster bean in India. Further comprehensive investigations will shed a light on the economic impact of powdery mildew disease on the cluster bean in India.

First report of Athelia rolfsii (=Sclerotium rolfsii) causing foot rot disease of chia (Salvia hispanica L.) in India.

Salvia hispanica L. (Lamiaceae) commonly called 'chia' is an important food crop that has gained significance in recent times globally due to its nutritive value. During a field survey (Mysore district, Karnataka, October, 2021), chia fields were found associated with a characteristic foot rot disease. Further, the presence of mycelial structures along with sclerotial bodies was recorded near the stem-soil interface on the infected plants. The disease incidence ranged 15-21% in an area of approximately 15 hectares of chia fields. The symptoms initially appeared as tan lesions near the stem soil interface and the lesions were colonized by the fast growing mycelium. As the disease progressed, the plants toppled due to death of the stem-root interface region. Infected plants from KM Halli (12º20'90"N; 76º37'68"E) and DMG Halli (12º28'50"N; 76º51'66"E) (n=30) were sampled and associated fungal pathogen isolated on potato dextrose agar (PDA; HiMedia Lab, Mumbai). Fungal mycelia developing from the infected tissues were inoculated on to fresh PDA plates to obtained pure cultures for further identification. Fungal colonies with dense, aerial whitish-cottony mycelia with uniformly globoid sclerotia (0.52.9 mm) were observed after 1012 days of incubation at room temperature. Sclerotia were white at first and turned brown with age. The average number of sclerotia produced per plate ranged from 150 to >280 (n = 10). To further to confirm the identity of the isolates, three representative isolates (SrSh1, SrSh5 and SrSh10) was subjected to molecular identification based on ITS-rDNA sequences. Briefly, genomic DNA was isolated from 12 day old cultures using the CTAB method and ITS-rDNA was amplified using ITS1-ITS4 primers (White et al., 1990). An expected amplicon of >650 bp was obtained and later sequenced from both the directions. The consensus sequences were analysed through nBLAST search which revealed that 100% (643/643 bp) sequence similarity with reference sequences of Athelia rolfsii (S. rolfsii) from GenBank database (KY640622 and AB075298). A phylogenetic tree obtained by the neighbor-joining method using MEGAX shared a common clade with the reference sequences retrieved and computed, thus confirming the identification based on sequence analysis and molecular phylogeny. The representative sequence of A. rolfsii isolates SrSh1, SrSh4 and SrSh7 isolates deposited in GenBank with Accession no OM021878-OM021880. Based on etiology, morphological, cultural and molecular data the pathogen was identified as Athelia rolfsii (Curzi) Tu & Kimbrough (Syn: Sclerotium rolfsii Sacc.) (Mordue, 1974; Mahadevakumar et al., 2016, 2018). Pathogenicity tests were conducted by inoculating the sclerotial bodies near stem soil interface of chia plants grown under green house (at 28 ± 2°C and 70% relative humidity). Briefly, a total of 60 healthy plants were inoculated with sclerotia and covered with polythene bags for 2 days and removed later. Plants (n=20) inoculated without any sclerotia were treated as controls. The development of characteristic foot rot disease was observed after 6-8 days post inoculation. A total of 38 plants showed the foot rot symptoms while control plants remained healthy. The identity of the fungus was confirmed by morphology and molecular sequence analysis after re-isolation. Chia is an important food crop and in recent times has been regarded as super food. Although S. rolfsii is known to be associated with many crops, this is the first report in chia. Therefore, to the best of our knowledge, this is the first report of foot rot disease caused by Sclerotium rolfsii on chia in India. Early diagnosis of this disease will help the farmers to adopt suitable management practices to avoid loss.

First report of Athelia rolfsii (=Sclerotium rolfsii) associated with southern blight disease of Macrotyloma uniflorum in India.

Horse gram (Macrotyloma uniflorum (Lam.) Verdc., Fabaceae) is an important legume crop cultivated widely in the arid and semiarid regions. During a survey carried out in the Mysore district (Karnataka, India, October 2021), horse gram plants showed the symptoms of southern blight disease. Disease incidence ranged from 20-27% in the approximate 52 hectares of horse gram fields evaluated. The symptoms initiated as tan lesions and the developing mycelial threads colonized the infected root-stem interface, causing girdling; lesions on leaves enlarged and developed into distinct spots. Infected parts (leaves & stem) (n=30) were collected in poly bags and incubated in a moist chamber overnight, followed by surface sterilization of small segments of stem, leaf with 2% NaOCl, rinsed with sterile water (SW), and placed onto the potato dextrose agar (PDA, HiMedia Lab, Mumbai) supplemented with chloramphenicol (40 mg/L). The plates were incubated at room temperature (28 ± 2°C) for 5-7 days. The fungal colonies developed from the diseased segments were sub-cultured through hyphal tipping to fresh PDA plates and pure cultures were obtained. Fungal colonies with dense, aerial whitish-cottony mycelia with uniformly globoid sclerotia (0.52.9 mm) were observed after 1012 days of incubation. Sclerotia were white in the beginning and turned to brown later. The average number of sclerotia produced per plate ranged from 112 to 320 (n = 20). To determine the identity of the isolated fungal pathogen, ITS-rDNA was amplified and sequenced using ITS1/ITS4 (White et al. 1990) primers. The amplified PCR product was purified and sequenced directly. The ITS sequences (OM037658 & OM037659) shared 100% (630/643bp) sequence similarity to Athelia rolfsii (KY640622.1, AB075298). The phylogenetic tree (Neighbour-Joining method) constructed based on ITS-rDNA region confirmed that the sequences shared a common clade with reference sequence of A. rolfsii. Thus the identity was confirmed based on micromorphology and phylogenetic analysis. Pathogenicity tests were conducted on a total of 20 plants (5-6 weeks old) in greenhouse conditions (at 28 ± 2°C and 70% relative humidity) by inoculating with sclerotia from 15 days old cultures on stem and leaves and 14 plants were found infected after 5 days of post-inoculation, while uninoculated control plants remained healthy. Similarly, detached leaf assay (Mahadevakumar et al., 2018) was performed under in vitro conditions at 28 ± 2°C in a moist chamber and 28 out of 30 leaves showed the leaf spot symptoms after 3-5 days of inoculation. Uninoculated control leaves remained healthy. The identity of the fungus was confirmed by morphology and molecular analysis after re-isolation. The occurrence as a pathogen on horse gram has not been previously reported elsewhere. This is the first report of southern blight disease caused by A. rolfsii on horse gram from India. Early diagnosis of this leaf spot disease will help the farmers to adopt suitable management practices to avoid loss in production.

Fungal Planet description sheets: 1436-1477.

Novel species of fungi described in this study include those from various countries as follows: Argentina, Colletotrichum araujiae on leaves, stems and fruits of Araujia hortorum. Australia, Agaricus pateritonsus on soil, Curvularia fraserae on dying leaf of Bothriochloa insculpta, Curvularia millisiae from yellowing leaf tips of Cyperus aromaticus, Marasmius brunneolorobustus on well-rotted wood, Nigrospora cooperae from necrotic leaf of Heteropogon contortus, Penicillium tealii from the body of a dead spider, Pseudocercospora robertsiorum from leaf spots of Senna tora, Talaromyces atkinsoniae from gills of Marasmius crinis-equi and Zasmidium pearceae from leaf spots of Smilaxglyciphylla. Brazil, Preussia bezerrensis from air. Chile, Paraconiothyrium kelleni from the rhizosphere of Fragaria chiloensis subsp. chiloensis f. chiloensis. Finland, Inocybe udicola on soil in mixed forest with Betula pendula, Populus tremula, Picea abies and Alnus incana. France, Myrmecridium normannianum on dead culm of unidentified Poaceae. Germany, Vexillomyces fraxinicola from symptomless stem wood of Fraxinus excelsior. India, Diaporthe limoniae on infected fruit of Limonia acidissima, Didymella naikii on leaves of Cajanus cajan, and Fulvifomes mangroviensis on basal trunk of Aegiceras corniculatum. Indonesia, Penicillium ezekielii from Zea mays kernels. Namibia, Neocamarosporium calicoremae and Neocladosporium calicoremae on stems of Calicorema capitata, and Pleiochaeta adenolobi on symptomatic leaves of Adenolobus pechuelii. Netherlands, Chalara pteridii on stems of Pteridium aquilinum, Neomackenziella juncicola (incl. Neomackenziella gen. nov.) and Sporidesmiella junci from dead culms of Juncus effusus. Pakistan, Inocybe longistipitata on soil in a Quercus forest. Poland, Phytophthora viadrina from rhizosphere soil of Quercus robur, and Septoria krystynae on leaf spots of Viscum album. Portugal (Azores), Acrogenospora stellata on dead wood or bark. South Africa, Phyllactinia greyiae on leaves of Greyia sutherlandii and Punctelia anae on bark of Vachellia karroo. Spain, Anteaglonium lusitanicum on decaying wood of Prunus lusitanica subsp. lusitanica, Hawksworthiomyces riparius from fluvial sediments, Lophiostoma carabassense endophytic in roots of Limbarda crithmoides, and Tuber mohedanoi from calcareus soils. Spain (Canary Islands), Mycena laurisilvae on stumps and woody debris. Sweden, Elaphomyces geminus from soil under Quercus robur. Thailand, Lactifluus chiangraiensis on soil under Pinus merkusii, Lactifluus nakhonphanomensis and Xerocomus sisongkhramensis on soil under Dipterocarpus trees. Ukraine, Valsonectria robiniae on dead twigs of Robinia hispida. USA, Spiralomyces americanus (incl. Spiralomyces gen. nov.) from office air. Morphological and culture characteristics are supported by DNA barcodes. Citation: Tan YP, Bishop-Hurley SL, Shivas RG, et al. 2022. Fungal Planet description sheets: 1436-1477. Persoonia 49: 261-350. https://doi.org/10.3767/persoonia.2022.49.08.

A new host record for Candidatus Phytoplasma cynodontis (16Sr XIV-A) associated with phyllody and fasciation of linseed (Linum usitatissimum) from India.

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.

Dactuliophora mysorensis sp. nov.: A New Species of Mycelia Sterilia Causing Zonate Leaf Spot on Cowpea in India.

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.

First Report of Nigrospora sphaerica associated with Leaf Spot Disease of Cowpea (Vigna unguiculata) from India.

Cowpea (Vigna unguiculata (L.) Walp) is one of the main legume crops grown in arid and semi-arid regions in the world. Brazil, Haiti, Myanmar, Nigeria, Sri Lanka, United States, and India contributes to the substantial production of cowpea at the global level (Mahadevakumar and Janardhana, 2012, 2014). Field surveys conducted during 2017-19 (August-September) in major cowpea growing regions of southern Karnataka revealed the occurrence of characteristic leaf spot disease of unknown etiology with an incidence ranging from 6 to 8%. Initially, the symptoms developed as small specks (1.5 to 3.5 mm), characterized by circular or irregular shape. These lesions began to develop from the leaf margin and regularly extended and coalesced to form larger lesions. After the successful manifestation of the symptoms on leaves, the associated fungal pathogen was isolated. In brief, the infected leaves were surface sterilized with 2% NaOCl for 2 min, rinsed thrice in sterile distilled water (SDW) and blotter dried. The leaf sections were placed on potato dextrose agar (PDA) in Petri plates and incubated at room temperature (27 ± 2°C) for 10 to 12 days. Mycelia developed from infected tissues were transferred to fresh PDA plates and pure cultures were obtained. Mycelia were initially white and eventually turned into gray. The conidia were black, single-celled, smooth, spherical to subspherical, 10 to 22 µm in diameter (n=30), and borne singly on a hyaline vesicle at the tip of each conidiophore. Based on the cultural features and conidial morphology, the fungus was identified as Nigrospora sp. Further, to identify the pathogen to the species level, the ITS region of the ribosomal RNA gene was amplified using primers ITS1 and ITS4 (White et al. 1990). The amplified PCR products were purified and sequenced. The nBLAST analysis showed 100% similarity with reference sequences from the GenBank database Nigrospora sphaerica (MT225783.1; MN795578.1), and the sequences were deposited in GenBank (Accession No. MT305812.1, MT305813.1, MT305814.1). Based on the cultural, morphological, microscopic and molecular characteristics, the associated fungal pathogen was identified as N. sphaerica (Sacc.) Mason (Chen et al. 2018; Wang et al. 2017) and a voucher specimen was deposited at University of Mysore Herbarium with accession No. UOM20-NS1. Further, pathogenicity tests were conducted on healthy cowpea plants grown under greenhouse conditions. Inoculations were made with conidial suspension (105 conidia/ml) prepared in SDW and healthy plants sprayed with SDW served as a standard control. All the plants were covered with polyethylene bags for 24-48 hr and observations were made at regular intervals. Typical necrotic lesions developed after 12 days of inoculation and no such symptoms were observed on the standard control set. The associated pathogen was re-isolated from diseased leaves and its identity confirmed based on morphology and cultural characteristics. Leaf spots are becoming a major problem in cowpea growing areas in recent years (Dactuliophora sp., Pestalotiopsis leaf spot, Alternaria leaf spot, and many others) (Mahadevakumar and Janardhana 2012, 2014). Recently, Aplosporella hesperidica causing collar rot on cowpea has been reported from the same region (Deepika et al. 2020). The seed borne occurrence N. sphaerica on cowpea is reported from Brazil (Rodrigues and Menezes 2002), there are no previous reports available on the occurrence of N. sphaerica on cowpea leaf spots, the present investigation is the first report of N. sphaerica causing leaf spot disease on cowpea from India.

A new collar rot disease of cowpea (Vigna unguiculata) caused by Aplosporella hesperidica in India.

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.

A New Rust Disease on Wild Coffee (Psychotria nervosa) Caused by Puccinia mysuruensis sp. nov.

Psychotria nervosa, commonly called "wild coffee" (Rubiaceae), is an important ethno-medicinal plant in India. In 2010, a new rust disease of P. nervosa was observed in three regions of Mysore District, Karnataka (India), with disease incidence ranging from 58 to 63%.Typical symptoms of the rust disease on wild coffee were prominently visible during the early monsoon season (May to June), with chlorotic spots on the adaxial and black pustules (telia) on the abaxial leaf surface. Telia produced abundant teliospores, which were bicelled, pedicillate, and measured 33 to 45 by 19 to 30 µm. The germination of teliospores produced a typical metabasidium bearing four basidiospores, each containing two haploid nuclei. Spore stages of the wild coffee rust pathogen were studied using artificially inoculated healthy wild coffee plants with germinated teliospores. Only telia were observed on the inoculated plants, indicating that this rust fungus has an abbreviated microcyclic life cycle that includes only teliospores and basidiospores. Phylogenetic analysis based on internal transcribed spacer and partial large subunit (LSU) sequence data showed that the wild coffee rust pathogen is related to Macruropyxis fraxini, Puccinia bartholomaei, P. choridis, and P. sparganioidis. The herbarium sample of P. psychotriae was examined and was shown to be different with respect to telium size and teliospore dimensions (24 to 32 by 13 to 18 µm). Therefore, the rust pathogen causing wild coffee rust is a new species, P. mysuruensis sp. nov.