Rust fungi (Pucciniales, Basidiomycota) of the Brazilian Cerrado: Taxonomic advances and new taxa in a threatened biome

Rust fungi on commercial Vitis cultivars, wild Vitaceae, and Meliosma (Sabiaceae), potential alternate hosts of a grapevine leaf rust (GLR) fungus, were surveyed in Thailand and Vietnam. Molecular phylogenetic analyses using the internal transcribed spacer 2 and the large-subunit rRNA gene (D1/D2 region) and morphological examinations confirmed that the GLR fungus distributed in Southeast Asia and Australasia is distinct from Neophysopella species involved in GLRs in East Asia and the Americas. Therefore, the Southeast Asian-Australasian GLR fungus is recognized as a new Neophysopella species and named as N. tropicalis. Two fungi on Meliosma species in Thailand were aecial anamorph of Neophysopella species. One parasitic on M. simplicifolia and M. simplicifolia subsp. fordii was previously named as Aecidium wareoense, and a new name, N. wareoensis, is proposed for it. Another on M. arnottiana in Thailand was phylogenetically and morphologically distinct from all other Meliosma rust fungi, and, therefore, it is recognized as a new species, N. sriphumensis. A uredinial-telial fungus on Ampelocissus araneosa (Vitaceae) in Thailand was morphologically similar to Phakopsora cronartiiformis on Parthencissus semicordata (Vitaceae) in the Himalayas. However, the former fungus was distinct from the latter in producing characteristic urediniospores with labyrinthiform surface structure and cone-shaped projections. It is, therefore, recognized as a new species, N. doipuiensis.

Through the morphological and molecular examinations of Melampsora species on willows, we clarified the taxonomic identity of the rust specimens on Salix bakko, S. hultenii and S. leucopithecia from Japan and described the following rust fungus as a new species, Melampsora salicis-bakko. This rust fungus resembled M. caprearum in morphology of teliospores, but it differed from M. caprearum mainly in the density of spines on the urediniospores. Molecular phylogenetic analyses using the rDNA ITS region (complete ITS1, 5.8S rRNA gene and ITS2) revealed that M. salicis-bakko was monophyletic, and that this rust fungus was distinct from other Melampsora species, including M. caprearum.

A new rust fungus was found on Lygodium flexuosum at Doi Suthep-Pui National Park in Chiang Mai Province, Thailand. Puccinia lygodii was the only rust fungus currently known on Lygodium spp. (Lygodioideae, Schizaeaceae, Schizaeales) from southern North America through northern South America. The new fungus produced uredinia linearly between veins, causing yellowish streaks, on the abaxial frond surface. The sori were covered with a layer of thin-walled fungal cells beneath the host epidermis and surrounded by thin-walled paraphyses. The sori did not have a distinct central aperture with ostiolar cells but ruptured irregularly to release urediniospores. Urediniospores were obovoid, obovoid-ellipsoid, or pyriform. The wall was thin, colorless, and completely echinulate. Neither amphispores nor teliospores were observed. The sorus and spore morphology indicated the taxonomic affinity of the fungus to the fern rust genera Hyalopsora and Milesina. A molecular phylogenetic analysis using nuclear large subunit ribosomal DNA sequence revealed that the Lygodium rust fungus was grouped in a paraphyletic Milesina clade. From the putative host preference, morphology, and estimated phylogenetic relationships, it was concluded that the fungus was a new species of Milesina.

Macruropyxis fraxini has been recorded on several species of Fraxinus in China, Japan, Russia (Far East), and North Korea since its first recorded observation as a rust fungus on F. rhynchophylla in Jilin, China, in 1899. In the Korean Peninsula, the rust fungus was first recorded on F. rhynchophylla in 1935, based on four specimens collected at Mt. Kumgangsan, Gangwondo Province, in the North Korean territory. We confirmed this rust in the Korean Peninsula after 82 years. The rust fungus was identified based on morphological characteristics and a molecular phylogenetic analysis. This is the first record of M. fraxini in South Korea.

Native vegetation across the Brazilian Cerrado is highly heterogeneous and biodiverse and provides important ecosystem services, including carbon and water balance regulation, however, land-use changes have been extensive. Conservation and restoration of native vegetation is essential and could be facilitated by detailed landcover maps. Here, across a large case study region in Goiás State, Brazil (1.1 Mha), we produced physiognomy level maps of native vegetation (n = 8) and other landcover types (n = 5). Seven different classification schemes using different combinations of input satellite imagery were used, with a Random Forest classifier and 2-stage approach implemented within Google Earth Engine. Overall classification accuracies ranged from 88.6–92.6% for native and non-native vegetation at the formation level (stage-1), and 70.7–77.9% for native vegetation at the physiognomy level (stage-2), across the seven different classifications schemes. The differences in classification accuracy resulting from varying the input imagery combination and quality control procedures used were small. However, a combination of seasonal Sentinel-1 (C-band synthetic aperture radar) and Sentinel-2 (surface reflectance) imagery resulted in the most accurate classification at a spatial resolution of 20 m. Classification accuracies when using Landsat-8 imagery were marginally lower, but still reasonable. Quality control procedures that account for vegetation burning when selecting vegetation reference data may also improve classification accuracy for some native vegetation types. Detailed landcover maps, produced using freely available satellite imagery and upscalable techniques, will be important tools for understanding vegetation functioning at the landscape scale and for implementing restoration projects.

1. Understanding of animal movement behaviour is critical for developing appropriate conservation strategies because of its profound implications for predicting species' responses to perturbations. To date there is a substantial knowledge gap of the movement behaviour of subterranean invertebrates.2. In this study temporary emigration (TE), the probability that an individual is absent from the cave on a given sampling occasion, was used as a method to inform on the movement and behaviour of cave‐dwelling invertebrates. Because these animals are difficult to study with traditional tracking techniques, the capture–recapture (CR) modelling framework was used to assess TE and to account for imperfect detectability and unobservable states.3. Specifically, the influence of season, sex, and surface weather variables on the TE of the facultative cave‐dwelling harvestman species, Paranemastoma sillii sillii (Herman, 1871), was investigated. Multistate CR models were used while accounting for individual heterogeneity on 999 individually marked adults of two populations inhabiting two caves, located in southwestern Romania.4. Harvestmen demonstrated clear heterogeneity and seasonality in TE. Findings showed that the TE of harvestmen exhibited variation between caves and there was little support for surface weather variables influencing TE and for sex‐specific TE patterns.5. These results show that the study of TE patterns is useful to gain valuable insights into movement and intrinsic behavioural processes of cave‐dwelling harvestmen. The method could potentially be used for other invertebrate groups with similar movement characteristics and when traditional tracking techniques are difficult.

North American species of the genus Symphyotrichum (‘asters’ or ‘Michaelmas daisies’) are popular, widely cultivated ornamentals, some of which have become invasive and widely naturalised in Europe, posing threats to natural ecosystems. A rust fungus was collected in October 2017 on naturalised S. lanceolatum in Baumgarten an der March, Lower Austria (voucher specimen WU 43136 deposited in the fungarium of the University of Vienna), and in October 2020 on S. novae-angliae in a garden in St. Willibald, Upper Austria (voucher specimen WU 43601). Infected plants displayed chlorotic spots on the upper leaf surfaces and uredinia with powdery urediniospores on the lower leaf surfaces and stems (Figs. 1-3). Urediniospores were ellipsoid to oblong-ellipsoid, polyangular, verrucose, 29-34 × 19-22 μm (Fig. 4). Based on these characteristics and the hosts, the rust fungus was identified preliminarily as Coleosporium montanum (McTaggart & Aime, 3). To confirm the species identification, we sequenced the ITS2-LSU and the LSU regions of samples WU 43601 and WU 43136, respectively. DNA was extracted from uredinia using an innuPREP DNA Micro Kit (Analytik Jena, Germany) following the manufacturer's instructions, with a lysis time of 20 hours. The ITS2-LSU and LSU were amplified and sequenced with primer pairs RUST2inv - LR5 and Rust28SF - LR5, respectively (McTaggart & Aime, 3 and references therein). The obtained sequences were deposited in GenBank (Accession Nos. MW284588, MW284589). An nBLAST analysis revealed 99.7-100% identity to sequences of C. montanum. In a molecular phylogenetic analysis, the collections were placed in a subclade of C. montanum composed of North American and Korean accessions from Symphyotrichum hosts (Fig. 5). Coleosporium montanum is native to North America and has been introduced into Asia (McTaggart & Aime, 3). To our knowledge, our records are the first for Europe, but there were a few recent Central European records from Symphyotrichum spp. that were likely misidentified as C. asterum (Scheuer, 4; Ellis, 2). Sequence differences between C. montanum accessions from Symphyotrichum and Solidago (Fig. 4) indicate that it may contain two host-specific cryptic species (McTaggart & Aime, 3). So far, from Europe, only the closely related C. solidaginis has been confirmed from Solidago spp. (Beenken et al., 1). No C. montanum teliospores were seen, but they were reported for an Austrian collection (as C. asterum) from S. lanceolatum (Scheuer, 4). Occurrences on potential alternate hosts, 2- or 3-needled pines (Pinus spp.), are as yet unknown in Europe. As the disease was observed only late in the season, it may have a minor impact on its Symphyotrichum hosts, but may affect their ornamental horticultural value. The authors thank Thomas Barta for communicating specimen WU 43136. Financial support for updating the inventory of alien fungal species for Austria by the Federal Environment Agency in the Austrian Program for Rural Development 2014-2020 is gratefully acknowledged. The new record is also associated with the ABOL project.

The genus Cerradoa (type species Cerradoa palmaea) was established in 1978 by Hennen and Ono and named after the Brazilian Cerrado biome. The holotype collected in Planaltina, Federal District, Brazil, belonged to the first rust fungus reported on palms (Arecaceae). For decades, the status of Cerradoa as a distinct genus has been regarded as doubtful, representing a synonym of Edythea (Uropyxidaceae) starting with the second edition of the Illustrated Genera of Rust Fungi in 1983. Our molecular phylogenetic analyses, as well as our morphological investigations, allowed us to reject this synonymy, leading to the reinstatement of Cerradoa within the Pucciniaceae. Cerradoa, together with morphologically similar genera such as the newly established Pseudocerradoa with two species (Ps. paullula and Ps. rhaphidophorae) infecting araceous hosts, the fern rust Desmella, and also P. engleriana, could not be assigned to any of the seven identified major lineages within the Pucciniaceae. Edythea, instead of being maintained as a member of the Uropyxidaceae, was herein placed in Pucciniaceae, shown phylogenetically in close relationship to Cumminsiella mirabilissima, both infecting the Berberidaceae. Additionally, our extensive phylogenetic analyses add guidance for future taxonomic revisions in the highly polyphyletic genus Puccinia and other established taxa within the family Pucciniaceae.

The Brazilian Cerrado is a large and expanding agricultural frontier, representing a hotspot of land‐use change (LUC) from natural vegetation to farmland. It is known that this type of LUC impacts soil organic matter (SOM) dynamics, particularly labile carbon (C) pools (living and non‐living), decreasing soil health and agricultural sustainability, as well as increasing soil greenhouse gas (GHG) emissions, and accelerating global climate change. In this study, we quantified the changes in the quantity and quality of SOM and GHG fluxes due to changes in land use and cropland management in the Brazilian Cerrado. The land uses studied were native vegetation (NV), pasture (PA) and four croplands, including the following management types: conventional tillage with a single soybean crop (CT), and three no‐tillage systems with two crops cultivated in the same year (i.e., soybean/sorghum (NT SSo ), soybean/millet (NT SMi ) and maize/sorghum (NT MSo )). Soil and gases were sampled in the rainy season (November, December and January) and dry season (May, July and September). The highest soil C and nitrogen (N) stocks (6.7 kg C m −2 and 0.5 kg N m −2 , 0–0.3‐m layer) were found under NV. LUC reduced C stocks by 25% in the CT and by 10% in the PA and NT. Soil N stocks were 30% lower in the PA and NT MSo and 15% lower in the croplands with soybean compared to NV. δ 13 C values clearly distinguished between the C‐origin from NV (−25‰) and that from other land uses (−16‰). Soil (0–0.1 m) under NV also presented higher labile‐C (625 g C m −2 ), microbial‐C (70 g C m −2 ) and microbial‐N (5.5 g N m −2 ), whereas other land uses presented values three times lower. GHG emissions (expressed as C‐equivalent) were highest in the NV (1.2 kg m −2 year −1 ), PA (1.3 kg m −2 year −1 ) and NT MSo (0.9 kg m −2 year −1 ) and were positively related to the higher SOM turnover in these systems. Our results suggest that in order to maintain SOM, it is necessary to adopt “best” management practices, that provide large plant residue inputs (above‐ and belowground). This can be seen as a pathway to achieving high food production with low GHG emissions.

Rust fungi are important pathogens of trees, ornamental plants, and food crops. Field research targeting rust diseases across Korea uncovered three distinct species of Neophysopella, affecting different members of the family Vitaceae. In our examination of both wild and cultivated grapevine (Vitis) species, including V. amurensis, V. coignetiae, and V. vinifera, we found N. meliosmaemyrianthae as well as a previously undescribed rust species, which we describe here as N. viticola sp. nov. Neophysopella ampelopsidis, which was previously identified as a rust pathogen of Vitis spp., has been observed to specifically infect Ampelopsis brevipedunculata. Through molecular sequence analysis of the ITS, LSU rDNA, and cox3 mtDNA regions, we determined the phylogenetic placements of these three species. Our morphological studies revealed the distinguishing features of N. viticola, particularly its unique teliospore layer and urediniospore dimensions. The emergence of N. viticola on economically valuable grapevines raises concerns about potential agricultural losses, highlighting the urgency for developing specialized management approaches in viticulture. Citation: Na DH, Choi Y-J, Shin H-D (2024). Taxonomy and phylogeny of three rust fungi parasitic on Vitaceae in Korea, with Neophysopella viticola sp. nov. on Vitis vinifera. Fungal Systematics and Evolution 14: 127-138. doi: 10.3114/fuse.2024.14.08.

A conversão de áreas nativas com o corte e queima de vegetação seguida do cultivo do solo resultam em mudanças na dinâmica da matéria orgânica do solo, com alterações nas emissões dos gases causadores de efeito estufa (GEE: CO2, CH4 e N2O) da biosfera para a atmosfera, que causam a elevação da temperatura média e, consequentemente, as mudanças climáticas globais. O objetivo deste estudo foi verificar as relações entre os fluxos de CO2, CH4 e N2O com a umidade, biomassa microbiana e as formas inorgânicas de N no solo com diferentes usos das terras no bioma Cerrado (Rio Verde, Goiás). O clima da região é do tipo Aw (Köppen-Geiger), e o solo foi classificado como Latossolo Vermelho distrófico caulinítico textura argilosa com vegetação original de Cerradão. O delineamento experimental foi inteiramente casualizado (DIC), com quatro tratamentos (áreas): vegetação nativa - Cerradão (CE); pastagem (PA) de braquiária, semeadura convencional (SC) de soja; e semeadura direta (SD) de milho sucedido por milheto. As emissões anuais de CO2 e N2O não mostraram diferenças significativas entre os tratamentos; isso ocorreu devido à elevada variação nos fluxos dos gases em decorrência da sazonalidade no clima, com as menores emissões observadas durante o inverno, devido à ausência da umidade do solo. A média na emissão de CO2 foi de 108,9 ± 85,6 mg m-2 h-1 , e para o N2O, de 13,5 ± 7,6 µg m-2 h-1. Os fluxos de CH4 apresentaram diferenças significativas somente para a pastagem, com emissão de 32 µg m-2 h-1 , enquanto nas demais áreas foram observados influxos entre 46 e 15 µg m-2 h-1 . Com os resultados das correlações, pode-se verificar que a umidade foi a variável do solo que apresentou maior correlação com o fluxo dos três gases de efeito estufa. O teor de N-NO3- e as emissões de CO2 mostraram correlações para todas as áreas. Quando consideradas as correlações para todos os tratamentos conjuntamente, verificou-se que os fluxos dos três gases apresentaram correlações significativas com os teores de C e N-microbiano. Contudo, a relação Cmicro:Nmicro não mostrou correlação significativa com o fluxo dos gases de efeito estufa. A pastagem foi a única situação em que os fluxos de CO2 e N2O apresentaram correlação com as quantidades de N-inorgânico. Os resultados sugerem que os fluxos dos GEE são dependentes do regime pluvial no bioma Cerrado, principalmente nas áreas cultivadas que recebem altas doses de fertilizantes para o aumento da produtividade.

Rust fungi are obligate plant parasites belonging to the order Pucciniales; they comprise about 7,800 species throughout the world. Some species seriously damage crops, vegetables, fruits and trees. Of these species, wheat stem rust (Puccinia graminis f. sp. tritici), Asian soybean rust (Phakopsora pachyrhizi) and myrtle rust (Puccinia psidii) have recently become major concerns worldwide, and this review, discusses recent rust disease outbreaks of Asian soybean rust and myrtle rust. Both rusts have very wide host ranges. Asian soybean rust has spread from its original region of distribution (eastern Asia) to many areas of soybean cultivation around the world. Myrtle rust is a new disease in areas where host plants were first introduced and has spread to other parts of the world including the areas where the host plants are indigenous. New diseases of economically important plants can occur by host shifts from wild host plants or host jumps from phylogenetically unrelated plant species. Recent advances in molecular phylogenetic studies have contributed to a revision of rust taxonomy. Molecular phylogenetic analyses, together with precise morphological observations and inoculation experiments, have identified taxonomic groups among populations that are morphologically very similar. Systematic, ecological and other basic biological studies of rust fungi in both cultivated and wild host plants are very important for developing methods to control rust diseases. Recent changes in the International Code of Botanical Nomenclature will surely affect the systematics of rust fungi.

The multicellular discoid convex teliospore heads represent a prominent generic feature of the genus Ravenelia. However, recent molecular phylogenetic work has shown that this is a convergent trait, and that this genus does not represent a natural group. In 2000, a rust fungus infecting the Caesalpinioid species Cenostigma macrophyllum (= C. gardnerianum) was described as Ravenelia cenostigmatis. This species shows some rare features, such as an extra layer of sterile cells between the cysts and the fertile teliospores, spirally ornamented urediniospores, as well as strongly incurved paraphyses giving the telia and uredinia a basket-like appearance. Using freshly collected specimens of Rav. cenostigmatis and Rav. spiralis on C. macrophyllum, our phylogenetic analyses based on the nuc 28S, nuc 18S, and mt CO3 (cytochrome c oxidase subunit 3) gene sequences demonstrated that these two rust fungi belong in a lineage within the Raveneliineae that is distinct from Ravenelia s. str. Besides proposing their recombination into the new genus Raveneliopsis (type species R. cenostigmatis) and briefly discussing their potentially close phylogenetic affiliations, we suggest that five other Ravenelia species that are morphologically and ecologically close to the type species of Raveneliopsis, i.e., Rav. corbula, Rav. corbuloides, Rav. parahybana, Rav. pileolarioides, and Rav. Striatiformis, may be recombined pending new collections and confirmation through molecular phylogenetic analyses.

In 1895 and 2001, rust fungi affecting Licania trees (Chrysobalanchaceae) in Brazil were described as Uredo licaniae by Hennings in the state of Goiás and as Phakopsora tomentosae by Ferreira et al. in the state of Amazonas, respectively. Recently, a Licania rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome c oxidase subunit III (CO3) gene sequences. Since the original type specimen of Ph. tomentosae is considered lost, we carefully reviewed the type description and questioned the identity of the telium, which justified the description of the fungus as a Phakopsora species. Furthermore, the additional revision of the type material described by Hennings revealed that Ph. tomentosae is a synonym of U. licaniae. Based on the morphological examinations, disease symptoms, and shared hosts, we concluded that the newly collected material is conspecific with U. licaniae. However, the phylogenetic analyses rejected allocation in Phakopsora and instead assigned the Licania rust fungus in a sister relationship with Austropuccinia psidii (Sphaerophragmiaceae), the causal agent of the globally invasive myrtle rust pathogen. We therefore favored a recombination of U. licaniae (syn. Ph. tomentosae) into Austropuccinia and proposed the new name Austropuccina licaniae for the second species now identified for this genus. The fungus shares conspicuous symptoms with A. psidii, causing often severe infections of growing leaves and shoots that lead to leaf necrosis, leaf shedding, and eventually to the dieback of entire shoots. In view of the very similar symptoms of its aggressively invasive sister species, we briefly discuss the current state of knowledge about A. licaniae and the potential risks, and the opportunity of its identification.

Colebrookea oppositifolia (Lamiaceae) is a valuable traditional therapeutic plant with a wool-like shrubby appearance, present mostly in subtropical regions of some Asian countries. This plant possesses anti-oxidant, anti-fungal and anti-microbial properties. Its leaves are used locally for the treatment of wounds and fracture and its roots are used for epilepsy. During phytopathogenic surveys conducted in Khyber Pakhtunkhwa and Azad Jammu and Kashmir, Pakistan, the rust fungus Olivea colebrookeae (Raveneliaceae, Pucciniales) was collected on this economically important plant. Based on morpho-anatomical characteristics and molecular phylogenetic analyses, it was determined that Olivea colebrookeae is related to the teak-rust genus Neoolivea, now placed in the Crossopsoraceae, Pucciniales. Thus, this rust fungus on Colebrookea oppositifolia is transferred to Neoolivea as Neoolivea colebrookeae and reported for the first time from Pakistan. Detailed morphology along with scanning electron micrographs are provided.