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The complete genome sequence of a novel sadwavirus infecting cattleya orchids in South East Queensland is described. Isometric virions of c. 27 nm diameter were observed in sap extracts viewed under a transmission electron microscope, and the genome sequence of this virus was determined by high-throughput sequencing. The viral genome consists of two RNA components, 5,910 and 4,435 nucleotides (nt) in length, each encoding a long polyprotein, with predicted cleavage sites at H/Y, E/G, Q/S, and Q/G for the RNA1 and T/G for the RNA2 translation products, respectively. RNA2 has an additional small ORF of 684 nt near the 3ʹ untranslated region. Phylogenetic analysis based on an amino acid sequence alignment of the Pro-Pol region suggested that this virus is most closely related to pineapple secovirus A, a member of the subgenus Cholivirus, but warrants classification as a member of a new species because it exhibited no more than 64% amino acid identity in pairwise sequence comparisons. Because of the prominent purple ringspots that were observed on the leaves of some of the plants, we propose the name “cattleya purple ringspot virus” for this virus (suggested species name: “Sadwavirus cattleyacola”).

Of all the plant diseases that occur in Australia, banana bunchy top disease would rank high on any list of those that have had the greatest impact on society. Bunchy top first became a major problem in Australia during World War 1 in the Tweed Valley in New South Wales, close to the border of Queensland. The Soldier Settlement Scheme was initiated to provide a livelihood for returned soldiers, and the Northern Rivers region of New South Wales was chosen as the site for a new subtropical fruit industry. Physically and psychologically damaged men were encouraged to settle on the land to grow bananas, only to be left in ruins within two years because bunchy top had destroyed their plantations. Bunchy top did not discriminate, and many other well-established growers also ‘went broke’. The cries for assistance from the banana growers made it to the federal Parliament in Melbourne, and a Bunchy Top Investigation Committee was formed in 1924 with funding equally contributed by the New South Wales, Queensland, and Australian Governments. Charles Magee was the full-time plant pathologist appointed to the investigation, and he did most of the research. Most histories of the bunchy top research program follow the written accounts of Magee, but he only provided a narrow perspective. Several of the major hypotheses about the epidemiology of bunchy top disease, such as that it was spread in the plant’s suckers and was vectored by the banana aphid Pentalonia nigronervosa, were established by growers such as William John (aka Jack) Burton Marks well before the Bunchy Top Investigation Committee began. This paper describes the beginnings of the subtropical banana industry, the introduction of bunchy top disease, and efforts by the scientific and farming communities to find a preventative treatment or cure for the disease.

Of all the plant diseases that occur in Australia, banana bunchy top disease would rank high on any list of those that have had the greatest impact on society. Bunchy top first became a major problem in Australia during World War 1 in the Tweed Valley in New South Wales, close to the border of Queensland. The Soldier Settlement Scheme was initiated to provide a livelihood for returned soldiers, and the Northern Rivers region of New South Wales was chosen as the site for a new subtropical fruit industry. Physically and psychologically damaged men were encouraged to settle on the land to grow bananas, only to be left in ruins within two years because bunchy top had destroyed their plantations. Bunchy top did not discriminate, and many other well-established growers also ‘went broke’. The cries for assistance from the banana growers made it to the federal Parliament in Melbourne, and a Bunchy Top Investigation Committee was formed in 1924 with funding equally contributed by the New South Wales, Queensland, and Australian Governments. Charles Magee was the full-time plant pathologist appointed to the investigation, and he did most of the research. Most histories of the bunchy top research program follow the written accounts of Magee, but he only provided a narrow perspective. Several of the major hypotheses about the epidemiology of bunchy top disease, such as that it was spread in the plant’s suckers and was vectored by the banana aphid Pentalonia nigronervosa, were established by growers such as William John (aka Jack) Burton Marks well before the Bunchy Top Investigation Committee began. This paper describes the beginnings of the subtropical banana industry, the introduction of bunchy top disease, and efforts by the scientific and farming communities to find a preventative treatment or cure for the disease.

Of all the plant diseases that occur in Australia, banana bunchy top disease would rank high on any list of those that have had the greatest impact on society. Bunchy top first became a major problem in Australia during World War 1 in the Tweed Valley in New South Wales, close to the border of Queensland. The Soldier Settlement Scheme was initiated to provide a livelihood for returned soldiers, and the Northern Rivers region of New South Wales was chosen as the site for a new subtropical fruit industry. Physically and psychologically damaged men were encouraged to settle on the land to grow bananas, only to be left in ruins within two years because bunchy top had destroyed their plantations. Bunchy top did not discriminate, and many other well-established growers also ‘went broke’. The cries for assistance from the banana growers made it to the federal Parliament in Melbourne, and a Bunchy Top Investigation Committee was formed in 1924 with funding equally contributed by the New South Wales, Queensland, and Australian Governments. Charles Magee was the full-time plant pathologist appointed to the investigation, and he did most of the research. Most histories of the bunchy top research program follow the written accounts of Magee, but he only provided a narrow perspective. Several of the major hypotheses about the epidemiology of bunchy top disease, such as that it was spread in the plant’s suckers and was vectored by the banana aphid Pentalonia nigronervosa, were established by growers such as William John (aka Jack) Burton Marks well before the Bunchy Top Investigation Committee began. This paper describes the beginnings of the subtropical banana industry, the introduction of bunchy top disease, and efforts by the scientific and farming communities to find a preventative treatment or cure for the disease.

The complete genome sequence of a novel sadwavirus infecting cattleya orchids in South East Queensland is described. Isometric virions of c. 27 nm diameter were observed in sap extracts viewed under a transmission electron microscope, and the genome sequence of this virus was determined by high-throughput sequencing. The viral genome consists of two RNA components, 5,910 and 4,435 nucleotides (nt) in length, each encoding a long polyprotein, with predicted cleavage sites at H/Y, E/G, Q/S, and Q/G for the RNA1 and T/G for the RNA2 translation products, respectively. RNA2 has an additional small ORF of 684 nt near the 3ʹ untranslated region. Phylogenetic analysis based on an amino acid sequence alignment of the Pro-Pol region suggested that this virus is most closely related to pineapple secovirus A, a member of the subgenus Cholivirus, but warrants classification as a member of a new species because it exhibited no more than 64% amino acid identity in pairwise sequence comparisons. Because of the prominent purple ringspots that were observed on the leaves of some of the plants, we propose the name “cattleya purple ringspot virus” for this virus (suggested species name: “Sadwavirus cattleyacola”).

An easy, rapid and inexpensive method of preparing RNA template for a reverse transcription qPCR assay for avocado sunblotch viroid (ASBVd) is described. This method depends on the principle of reversible binding of viroid RNA to filter paper under different concentrations of monovalent cation. Lysis buffers containing either sodium or lithium chloride were compared, and 1.5 M lithium chloride was shown to be optimal for the adsorption of the viroid RNA to the filter paper. The extraction method was validated using field samples and equivalent yields of viroid RNA were obtained using this method and either a commercial RNA extraction kit or a dsRNA chromatography method. The filter paper method of RNA extraction is ideally suited for the large-scale surveillance for ASBVd.

The island nations of the Pacific are scattered across a vast expanse of ocean and face many unique plant biosecurity challenges. This talk will focus on biosecurity as it relates to traditional crops such as banana, coconut, sweet potato and taro, and highlight specific case studies to demonstrate difficulties with containing and controlling pests and pathogens in this region. Some of the most serious pests and pathogens such as the coconut rhinoceros beetle and banana bunchy top virus date back 100 years to the period of European colonization but are still proving difficult to control, with new spread pathways still being uncovered. There are other emerging pests and pathogens such as the coconut and banana wilt-associated phytoplasmas, which are likely indigenous to the region but for reasons that are unclear, are increasing in importance. Lessons that have been learnt from these case studies will be discussed and recommendations for the future put forward. Australia has a vested interest in ensuring a strong biosecurity system in this region as it represents a major entry point for pests and pathogens that could affect our northern Australian agricultural industries.

The island nations of the Pacific are scattered across a vast expanse of ocean and face many unique plant biosecurity challenges. This talk will focus on biosecurity as it relates to traditional crops such as banana, coconut, sweet potato and taro, and highlight specific case studies to demonstrate difficulties with containing and controlling pests and pathogens in this region. Some of the most serious pests and pathogens such as the coconut rhinoceros beetle and banana bunchy top virus date back 100 years to the period of European colonization but are still proving difficult to control, with new spread pathways still being uncovered. There are other emerging pests and pathogens such as the coconut and banana wilt-associated phytoplasmas, which are likely indigenous to the region but for reasons that are unclear, are increasing in importance. Lessons that have been learnt from these case studies will be discussed and recommendations for the future put forward. Australia has a vested interest in ensuring a strong biosecurity system in this region as it represents a major entry point for pests and pathogens that could affect our northern Australian agricultural industries.

The island nations of the Pacific are scattered across a vast expanse of ocean and face many unique plant biosecurity challenges. This talk will focus on biosecurity as it relates to traditional crops such as banana, coconut, sweet potato and taro, and highlight specific case studies to demonstrate difficulties with containing and controlling pests and pathogens in this region. Some of the most serious pests and pathogens such as the coconut rhinoceros beetle and banana bunchy top virus date back 100 years to the period of European colonization but are still proving difficult to control, with new spread pathways still being uncovered. There are other emerging pests and pathogens such as the coconut and banana wilt-associated phytoplasmas, which are likely indigenous to the region but for reasons that are unclear, are increasing in importance. Lessons that have been learnt from these case studies will be discussed and recommendations for the future put forward. Australia has a vested interest in ensuring a strong biosecurity system in this region as it represents a major entry point for pests and pathogens that could affect our northern Australian agricultural industries.

Banana bunchy top virus is reported for the first time in Laos. Infected plants showed typical disease symptoms and the two complete genome sequences reported place the isolates in the Southeast Asian subgroup.

Banana bunchy top virus is reported for the first time in Laos. Infected plants showed typical disease symptoms and the two complete genome sequences reported place the isolates in the Southeast Asian subgroup.

Two near complete polerovirus genomes were assembled using high throughput sequencing (HTS) data from two separate samples of garlic cultivar ‘Glenlarge’ grown in Gatton, Queensland, Australia. Whole genome sequence comparisons showed that one contig shared 96.7% nucleotide identity with phasey bean mild yellows virus (MT966032.1) and the other, 99.8% nucleotide identity with turnip yellows virus (MT586581.1). Phylogenetic analyses further revealed that the isolates fell within the PBMYV group 2 and TuYV group 2 clades, respectively. This is the first report of these poleroviruses infecting garlic.

Bermuda grass latent virus (BGLV; genus Panicovirus) is identified for the first time in Australia and in only the second country after the USA. A full-length genome sequence was obtained, which has 97% nucleotide sequence identity to that of the species exemplar isolate. Surveys for BGLV, utilising a newly designed universal panicovirus RT-PCR assay for diagnosis, demonstrated widespread infection by this virus in a broad variety of Bermuda grass cultivars (Cynodon dactylon and C. dactylon × C. transvaalensis) grown in both New South Wales and Queensland. The virus was also detected in Rhodes grass (Chloris gayana) and Kikuyu grass (Cenchrus clandestinus), which are both important pasture grasses in subtropical Australia, and the latter is also grown as turf. Furthermore, the Rhodes grass plant, which had strong mosaic symptoms, was also infected with sugarcane mosaic virus, warranting further investigations as to whether synergistic interactions occur between these two viruses.

An easy, rapid and inexpensive method of preparing RNA template for a reverse transcription qPCR assay for avocado sunblotch viroid (ASBVd) is described. This method depends on the principle of reversible binding of viroid RNA to filter paper under different concentrations of monovalent cation. Lysis buffers containing either sodium or lithium chloride were compared, and 1.5 M lithium chloride was shown to be optimal for the adsorption of the viroid RNA to the filter paper. The extraction method was validated using field samples and equivalent yields of viroid RNA were obtained using this method and either a commercial RNA extraction kit or a dsRNA chromatography method. The filter paper method of RNA extraction is ideally suited for the large-scale surveillance for ASBVd.

The island nations of the Pacific are scattered across a vast expanse of ocean and face many unique plant biosecurity challenges. This talk will focus on biosecurity as it relates to traditional crops such as banana, coconut, sweet potato and taro, and highlight specific case studies to demonstrate difficulties with containing and controlling pests and pathogens in this region. Some of the most serious pests and pathogens such as the coconut rhinoceros beetle and banana bunchy top virus date back 100 years to the period of European colonization but are still proving difficult to control, with new spread pathways still being uncovered. There are other emerging pests and pathogens such as the coconut and banana wilt-associated phytoplasmas, which are likely indigenous to the region but for reasons that are unclear, are increasing in importance. Lessons that have been learnt from these case studies will be discussed and recommendations for the future put forward. Australia has a vested interest in ensuring a strong biosecurity system in this region as it represents a major entry point for pests and pathogens that could affect our northern Australian agricultural industries.

Banana bunchy top virus is reported for the first time in Laos. Infected plants showed typical disease symptoms and the two complete genome sequences reported place the isolates in the Southeast Asian subgroup.

An easy, rapid and inexpensive method of preparing RNA template for a reverse transcription qPCR assay for avocado sunblotch viroid (ASBVd) is described. This method depends on the principle of reversible binding of viroid RNA to filter paper under different concentrations of monovalent cation. Lysis buffers containing either sodium or lithium chloride were compared, and 1.5 M lithium chloride was shown to be optimal for the adsorption of the viroid RNA to the filter paper. The extraction method was validated using field samples and equivalent yields of viroid RNA were obtained using this method and either a commercial RNA extraction kit or a dsRNA chromatography method. The filter paper method of RNA extraction is ideally suited for the large-scale surveillance for ASBVd.

An easy, rapid and inexpensive method of preparing RNA template for a reverse transcription qPCR assay for avocado sunblotch viroid (ASBVd) is described. This method depends on the principle of reversible binding of viroid RNA to filter paper under different concentrations of monovalent cation. Lysis buffers containing either sodium or lithium chloride were compared, and 1.5 M lithium chloride was shown to be optimal for the adsorption of the viroid RNA to the filter paper. The extraction method was validated using field samples and equivalent yields of viroid RNA were obtained using this method and either a commercial RNA extraction kit or a dsRNA chromatography method. The filter paper method of RNA extraction is ideally suited for the large-scale surveillance for ASBVd.

Two near complete polerovirus genomes were assembled using high throughput sequencing (HTS) data from two separate samples of garlic cultivar ‘Glenlarge’ grown in Gatton, Queensland, Australia. Whole genome sequence comparisons showed that one contig shared 96.7% nucleotide identity with phasey bean mild yellows virus (MT966032.1) and the other, 99.8% nucleotide identity with turnip yellows virus (MT586581.1). Phylogenetic analyses further revealed that the isolates fell within the PBMYV group 2 and TuYV group 2 clades, respectively. This is the first report of these poleroviruses infecting garlic.

Bermuda grass latent virus (BGLV; genus Panicovirus) is identified for the first time in Australia and in only the second country after the USA. A full-length genome sequence was obtained, which has 97% nucleotide sequence identity to that of the species exemplar isolate. Surveys for BGLV, utilising a newly designed universal panicovirus RT-PCR assay for diagnosis, demonstrated widespread infection by this virus in a broad variety of Bermuda grass cultivars (Cynodon dactylon and C. dactylon × C. transvaalensis) grown in both New South Wales and Queensland. The virus was also detected in Rhodes grass (Chloris gayana) and Kikuyu grass (Cenchrus clandestinus), which are both important pasture grasses in subtropical Australia, and the latter is also grown as turf. Furthermore, the Rhodes grass plant, which had strong mosaic symptoms, was also infected with sugarcane mosaic virus, warranting further investigations as to whether synergistic interactions occur between these two viruses.

Full genome sequences are presented for two isolates of Spartina mottle virus (SpMoV) from two accessions of the hybrid turf grass Cynodon dactylon × C. transvaalensis (Bermuda grass, green couch), originally from the USA but detected during post-entry quarantine in Australia. Both isolates had a genome of 9,346 nucleotides, encoding a single polyprotein of 3,029 amino acids and predicted to be cleaved into 10 mature proteins. Phylogenetic analysis strongly supported placement in a new genus within the family Potyviridae. The isolates possess 715–780 × 11–12 nm flexuous virions and produce cylindrical (pinwheel) inclusions in infected cells. They were mechanically transmitted to several species in the Poaceae including Zea mays (maize, sweet corn), Chloris gayana (Rhodes grass), and Echinochloa colona (awnless barnyard grass).

The genome sequence of a new subgroup C nepovirus from Stenotaphrum secundatum in Australia is described. This virus, tentatively named Stenotaphrum nepovirus (SteNV), was present in separate plants as a mixed infection with either sugarcane mosaic virus or Panicum mosaic virus. The virus genome was divided between two RNA segments, 7,824 and 7,104 nucleotides (nt) in length, which each encode a single long polyprotein with putative 3C-like cysteine protease sites of the type H/G, H/S or L/S. The 3ʹ untranslated region of RNA2, at 2,155 nt, is the longest observed for any subgroup C nepovirus. Phylogenetic analyses using protease-polymerase and coat protein amino acid alignments suggest that SteNV is most closely related to cherry leaf roll virus. Using a newly developed RT-PCR assay, this virus was detected at multiple localities in New South Wales, Queensland and Western Australia, and in a second host species, Digitaria didactyla. No consistent association between virus infection and symptoms could be established. The economic importance, pathogenicity and transmission of this novel virus species warrant further investigation.

Full genome sequences are presented for two isolates of Spartina mottle virus (SpMoV) from two accessions of the hybrid turf grass Cynodon dactylon × C. transvaalensis (Bermuda grass, green couch), originally from the USA but detected during post-entry quarantine in Australia. Both isolates had a genome of 9,346 nucleotides, encoding a single polyprotein of 3,029 amino acids and predicted to be cleaved into 10 mature proteins. Phylogenetic analysis strongly supported placement in a new genus within the family Potyviridae. The isolates possess 715–780 × 11–12 nm flexuous virions and produce cylindrical (pinwheel) inclusions in infected cells. They were mechanically transmitted to several species in the Poaceae including Zea mays (maize, sweet corn), Chloris gayana (Rhodes grass), and Echinochloa colona (awnless barnyard grass).

Full genome sequences are presented for two isolates of Spartina mottle virus (SpMoV) from two accessions of the hybrid turf grass Cynodon dactylon × C. transvaalensis (Bermuda grass, green couch), originally from the USA but detected during post-entry quarantine in Australia. Both isolates had a genome of 9,346 nucleotides, encoding a single polyprotein of 3,029 amino acids and predicted to be cleaved into 10 mature proteins. Phylogenetic analysis strongly supported placement in a new genus within the family Potyviridae. The isolates possess 715–780 × 11–12 nm flexuous virions and produce cylindrical (pinwheel) inclusions in infected cells. They were mechanically transmitted to several species in the Poaceae including Zea mays (maize, sweet corn), Chloris gayana (Rhodes grass), and Echinochloa colona (awnless barnyard grass).

The genome sequence of a new subgroup C nepovirus from Stenotaphrum secundatum in Australia is described. This virus, tentatively named Stenotaphrum nepovirus (SteNV), was present in separate plants as a mixed infection with either sugarcane mosaic virus or Panicum mosaic virus. The virus genome was divided between two RNA segments, 7,824 and 7,104 nucleotides (nt) in length, which each encode a single long polyprotein with putative 3C-like cysteine protease sites of the type H/G, H/S or L/S. The 3ʹ untranslated region of RNA2, at 2,155 nt, is the longest observed for any subgroup C nepovirus. Phylogenetic analyses using protease-polymerase and coat protein amino acid alignments suggest that SteNV is most closely related to cherry leaf roll virus. Using a newly developed RT-PCR assay, this virus was detected at multiple localities in New South Wales, Queensland and Western Australia, and in a second host species, Digitaria didactyla. No consistent association between virus infection and symptoms could be established. The economic importance, pathogenicity and transmission of this novel virus species warrant further investigation.

Full genome sequences are presented for two isolates of Spartina mottle virus (SpMoV) from two accessions of the hybrid turf grass Cynodon dactylon × C. transvaalensis (Bermuda grass, green couch), originally from the USA but detected during post-entry quarantine in Australia. Both isolates had a genome of 9,346 nucleotides, encoding a single polyprotein of 3,029 amino acids and predicted to be cleaved into 10 mature proteins. Phylogenetic analysis strongly supported placement in a new genus within the family Potyviridae. The isolates possess 715–780 × 11–12 nm flexuous virions and produce cylindrical (pinwheel) inclusions in infected cells. They were mechanically transmitted to several species in the Poaceae including Zea mays (maize, sweet corn), Chloris gayana (Rhodes grass), and Echinochloa colona (awnless barnyard grass).

Novel species of fungi described in this study include those from various countries as follows: Antartica , Cladosporium austrolitorale from coastal sea sand. Australia , Austroboletus yourkae on soil, Crepidotus innuopur- pureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium , Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil , Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada , Cuphophyllus bondii from a grassland. Croatia , Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus , Amanita exilis on calcareous soil. Czech Republic , Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark , Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic , Calocybella goethei among grass on a lawn. France (Corsica) , Inocybe corsica on wet ground. France (French Guiana) , Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany , Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India , Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran , Pythium serotinoosporum from soil under Prunus dulcis. Italy , Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan , Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan , Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia , Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Eup

Novel species of fungi described in this study include those from various countries as follows: Antartica , Cladosporium austrolitorale from coastal sea sand. Australia , Austroboletus yourkae on soil, Crepidotus innuopur- pureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium , Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil , Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada , Cuphophyllus bondii from a grassland. Croatia , Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus , Amanita exilis on calcareous soil. Czech Republic , Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark , Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic , Calocybella goethei among grass on a lawn. France (Corsica) , Inocybe corsica on wet ground. France (French Guiana) , Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany , Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India , Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran , Pythium serotinoosporum from soil under Prunus dulcis. Italy , Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan , Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan , Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia , Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Eup

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii fromagrassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis oncalcareoussoil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceousdebris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica) , Inocybe corsica onwetground. France (French Guiana) , Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. [...]

The badnavirus replication cycle is poorly understood and most knowledge is based on extrapolations from model viruses such as Cauliflower mosaic virus (CaMV). However, in contrast to CaMV, badnaviruses are thought not to produce viroplasms and therefore it has been a mystery as to where virion assembly occurs. In this study, ultrathin sections of a banana leaf infected with a badnavirus, banana streak MY virus (BSMYV), were examined by transmission electron microscopy. Electron-dense inclusion bodies (EDIBs) were sporadically distributed in parenchymatous tissues of the leaf, most commonly in the palisade and spongy mesophyll cells. These EDIBs had a characteristic structure, comprising an electron-dense core, a single, encircling lacuna and an outer ring of electron-dense material. However, much less frequently, EDIBs with two or three lacunae were observed. In the outer ring, densely packed virions were visible with a shape and size consistent with that expected for badnaviruses. Immunogold labelling was done with primary antibodies that detected the N-terminus of the capsid protein and strong labelling of the outer ring but not the central core or lacuna was observed. It is concluded that the EDIBs that were observed are equivalent in function to the viroplasms of CaMV, although obviously different in composition as there is not a paralogue of the transactivation/viroplasm protein in the badnavirus genome. It is postulated that production of a viroplasm could be a conserved characteristic of all members of the Caulimoviridae.

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

The badnavirus replication cycle is poorly understood and most knowledge is based on extrapolations from model viruses such as Cauliflower mosaic virus (CaMV). However, in contrast to CaMV, badnaviruses are thought not to produce viroplasms and therefore it has been a mystery as to where virion assembly occurs. In this study, ultrathin sections of a banana leaf infected with a badnavirus, banana streak MY virus (BSMYV), were examined by transmission electron microscopy. Electron-dense inclusion bodies (EDIBs) were sporadically distributed in parenchymatous tissues of the leaf, most commonly in the palisade and spongy mesophyll cells. These EDIBs had a characteristic structure, comprising an electron-dense core, a single, encircling lacuna and an outer ring of electron-dense material. However, much less frequently, EDIBs with two or three lacunae were observed. In the outer ring, densely packed virions were visible with a shape and size consistent with that expected for badnaviruses. Immunogold labelling was done with primary antibodies that detected the N-terminus of the capsid protein and strong labelling of the outer ring but not the central core or lacuna was observed. It is concluded that the EDIBs that were observed are equivalent in function to the viroplasms of CaMV, although obviously different in composition as there is not a paralogue of the transactivation/viroplasm protein in the badnavirus genome. It is postulated that production of a viroplasm could be a conserved characteristic of all members of the Caulimoviridae.

Garlic virus E (GarVE) is reported for the first time in Australia, from four accessions in a garlic germplasm collection planted at Gatton in South East Queensland. The presence of the virus was confirmed by reverse transcriptase PCR using GarVE-specific primers, followed by direct sequencing of the PCR product. The isolates had 99.1–99.7% nucleotide identity to each other, and 97.9–98.5% nucleotide sequence identity to the exemplar isolate for the species within the amplified region covering parts of the coat protein and nucleic acid binding protein genes. The distribution and economic impact of the virus in commercial plantings needs to be determined.

In 2016, severe pod distortion and leaf mottling in green beans (Phaseolus vulgaris) for the fresh market (Figs. 1-2; isolate Q5288) occurred in the Fassifern production area in south Queensland, Australia. Disease incidence in crops was 60-100%, resulting in losses of up to $AUD 400,000. A sample of soybean (Glycine max cv. Zam-1) displaying similar leaf symptoms (Fig. 3; isolate Q5294) was collected from a crop, about 50 km from the infected bean crops. Disease incidence in this crop was 5-10%. Both isolates were transmitted by manual inoculation and by Bemisia tabaci (MEAM1) from infected bean plants to uninfected soybean and bean. All test plants developed symptoms similar to the original samples. The inoculated plants tested negative for potyvirus using an ImmunoStrip test (Agdia, USA) and a group-specific RT-PCR (Langeveld et al., 1991; Gibbs & Mackenzie, 1997). Flexuous virions 600-700 nm in length (Fig. 4) were observed in the inoculated plants The virion morphology is consistent with carlaviruses and the samples tested positive in DAS-ELISA with antibodies (DSMZ, Germany) for the carlavirus, Cowpea mild mottle virus (CPMMV). The virus has since been detected in Australia's major winter bean production area, some 1000 km distant from the original detection site. In 2019, the carlavirus was also identified from Bundaberg in south Queensland where disease incidence exceeded 50% with significant production losses from deformed, unmarketable pods. The detection of the virus in regions producing 80% of Australia's fresh green beans and the high susceptibility of major commercial varieties has prompted new research on virus epidemiology and management. Amplicons covering part of the coat protein gene through to the 3′ end of the genome were obtained by RT-PCR amplification using the oligo-dT primer Poty 1 (Gibbs & Mackenzie, 1997) as the reverse primer for both isolates and the forward primer Carla7190F (5′-GGNYTNGGNGTICCIACIGARCAYGT-3′; designed to detect a range

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

The badnavirus replication cycle is poorly understood and most knowledge is based on extrapolations from model viruses such as Cauliflower mosaic virus (CaMV). However, in contrast to CaMV, badnaviruses are thought not to produce viroplasms and therefore it has been a mystery as to where virion assembly occurs. In this study, ultrathin sections of a banana leaf infected with a badnavirus, banana streak MY virus (BSMYV), were examined by transmission electron microscopy. Electron-dense inclusion bodies (EDIBs) were sporadically distributed in parenchymatous tissues of the leaf, most commonly in the palisade and spongy mesophyll cells. These EDIBs had a characteristic structure, comprising an electron-dense core, a single, encircling lacuna and an outer ring of electron-dense material. However, much less frequently, EDIBs with two or three lacunae were observed. In the outer ring, densely packed virions were visible with a shape and size consistent with that expected for badnaviruses. Immunogold labelling was done with primary antibodies that detected the N-terminus of the capsid protein and strong labelling of the outer ring but not the central core or lacuna was observed. It is concluded that the EDIBs that were observed are equivalent in function to the viroplasms of CaMV, although obviously different in composition as there is not a paralogue of the transactivation/viroplasm protein in the badnavirus genome. It is postulated that production of a viroplasm could be a conserved characteristic of all members of the Caulimoviridae.

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

The badnavirus replication cycle is poorly understood and most knowledge is based on extrapolations from model viruses such as Cauliflower mosaic virus (CaMV). However, in contrast to CaMV, badnaviruses are thought not to produce viroplasms and therefore it has been a mystery as to where virion assembly occurs. In this study, ultrathin sections of a banana leaf infected with a badnavirus, banana streak MY virus (BSMYV), were examined by transmission electron microscopy. Electron-dense inclusion bodies (EDIBs) were sporadically distributed in parenchymatous tissues of the leaf, most commonly in the palisade and spongy mesophyll cells. These EDIBs had a characteristic structure, comprising an electron-dense core, a single, encircling lacuna and an outer ring of electron-dense material. However, much less frequently, EDIBs with two or three lacunae were observed. In the outer ring, densely packed virions were visible with a shape and size consistent with that expected for badnaviruses. Immunogold labelling was done with primary antibodies that detected the N-terminus of the capsid protein and strong labelling of the outer ring but not the central core or lacuna was observed. It is concluded that the EDIBs that were observed are equivalent in function to the viroplasms of CaMV, although obviously different in composition as there is not a paralogue of the transactivation/viroplasm protein in the badnavirus genome. It is postulated that production of a viroplasm could be a conserved characteristic of all members of the Caulimoviridae.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

Couch smut, caused by Ustilago cynodontis, is an economically important disease of Cynodon dactylon, the most widely planted warm season turfgrass in Australia. The disease is distributed across all states and mainland territories of Australia, and is found worldwide wherever the host plant is present. The most characteristic disease symptoms are expressed at the flowering stage, when the inflorescence is partly or entirely destroyed and covered by a mass of black powdery spores. However, there are also less obvious impacts of the disease on plant growth such as a more erect growth habit, and a reduced rate of stolon extension and root development, leading to lower levels of tolerance of the turf to wear during usage, and greater amounts of wastage during harvest due to the roll breaking at points of infection. Ustilago cynodontis was first described nearly 130 years ago but pathogen biology and disease epidemiology are still poorly understood, hindering development of disease management strategies. We review the current knowledge and understanding of couch smut biology, the history of its occurrence, distribution and impact, and existing disease management practices to identify the gaps in knowledge that require further research.

This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively.

In 2016, severe pod distortion and leaf mottling in green beans (Phaseolus vulgaris) for the fresh market (Figs. 1-2; isolate Q5288) occurred in the Fassifern production area in south Queensland, Australia. Disease incidence in crops was 60-100%, resulting in losses of up to $AUD 400,000. A sample of soybean (Glycine max cv. Zam-1) displaying similar leaf symptoms (Fig. 3; isolate Q5294) was collected from a crop, about 50 km from the infected bean crops. Disease incidence in this crop was 5-10%. Both isolates were transmitted by manual inoculation and by Bemisia tabaci (MEAM1) from infected bean plants to uninfected soybean and bean. All test plants developed symptoms similar to the original samples. The inoculated plants tested negative for potyvirus using an ImmunoStrip test (Agdia, USA) and a group-specific RT-PCR (Langeveld et al., 1991; Gibbs & Mackenzie, 1997). Flexuous virions 600-700 nm in length (Fig. 4) were observed in the inoculated plants The virion morphology is consistent with carlaviruses and the samples tested positive in DAS-ELISA with antibodies (DSMZ, Germany) for the carlavirus, Cowpea mild mottle virus (CPMMV). The virus has since been detected in Australia's major winter bean production area, some 1000 km distant from the original detection site. In 2019, the carlavirus was also identified from Bundaberg in south Queensland where disease incidence exceeded 50% with significant production losses from deformed, unmarketable pods. The detection of the virus in regions producing 80% of Australia's fresh green beans and the high susceptibility of major commercial varieties has prompted new research on virus epidemiology and management. Amplicons covering part of the coat protein gene through to the 3′ end of the genome were obtained by RT-PCR amplification using the oligo-dT primer Poty 1 (Gibbs & Mackenzie, 1997) as the reverse primer for both isolates and the forward primer Carla7190F (5′-GGNYTNGGNGTICCIACIGARCAYGT-3′; designed to detect a range

Garlic virus E (GarVE) is reported for the first time in Australia, from four accessions in a garlic germplasm collection planted at Gatton in South East Queensland. The presence of the virus was confirmed by reverse transcriptase PCR using GarVE-specific primers, followed by direct sequencing of the PCR product. The isolates had 99.1–99.7% nucleotide identity to each other, and 97.9–98.5% nucleotide sequence identity to the exemplar isolate for the species within the amplified region covering parts of the coat protein and nucleic acid binding protein genes. The distribution and economic impact of the virus in commercial plantings needs to be determined.

We report the first fully sequenced genome of an Australian isolate of Cauliflower mosaic virus. The circular genome is 8022 base pairs in length. A phylogenetic analysis suggests recent common ancestry of this virus isolate with those from Japan and the USA, and origins of the clade in western Europe.