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Abstract Sphaerellopsisspecies are putative hyperparasites of rust fungi and may be promising biological control agents (BCA) of rust diseases. However, few detailed studies limit potential BCA development inSphaerellopsis. Here, we explored the biogeography, host-specificity, and species diversity ofSphaerellopsisand examined the early infection stage of one species, S. macroconidialis,to infer its trophic status. We randomly screened 5,621 rust specimens spanning 99 genera at the Arthur Fungarium for the presence ofSphaerellopsis. We identified 199 rust specimens infected withSphaerellopsisspecies on which we conducted morphological and multi-locus phylogenetic analyses. FiveSphaerellopsisspecies were recovered, infecting a total of 122 rust species in 18 genera from 34 countries.Sphaerellopsis melampsorinearumsp. nov. is described as a new species based on molecular phylogenetic data and morphological features of the sexual and asexual morphs.Sphaerellopsis paraphysatawas the most commonly encountered species, found on 77 rust specimens, followed bySphaerellopsis macroconidialison 56 andS. melampsorinearumon 55 examined specimens. The type species,Sphaerellopsis filum, was found on 12 rust specimens andSphaerellopsis hakeaeon a single specimen. We also recovered and documented for the first time, the sexual morph ofS. macroconidialis, from a specimen collected in Brazil. Our data indicate thatSphaerellopsisspecies are not host specific and furthermore that most species are cosmopolitan in distribution. However,S. paraphysatais more abundant in the tropics, andS. hakeaemay be restricted to Australia. Finally, we confirm the mycoparasitic strategy ofS. macroconidialisthroughin-vitrointeraction tests with the urediniospores ofPuccinia polysora. Shortly after germination, hyphae ofS. macroconidialisbegan growing along the germ tubes ofP. polysoraand coiling around them. After 12 days of co-cultivation, turgor loss was evident in the germ tubes ofP. polysora, and appressorium-like structures had formed on urediniospores. The interaction studies indicate thatSphaerellopsisspecies may be more effective as a BCA during the initial stages of rust establishment.
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Notes on Trochila (Ascomycota, Leotiomycetes), with new species and combinations
Studies of Trochila (Leotiomycetes, Helotiales, Cenangiaceae) are scarce. Here, we describe two new species based on molecular phylogenetic data and morphology. Trochila bostonensis was collected at the Boston Harbor Islands National Recreation Area, Massachusetts. It was found on the stem of Asclepias syriaca , representing the first report of any Trochila species from a plant host in the family Apocynaceae. Trochila urediniophila is associated with the uredinia of the rust fungus Cerotelium fici . It was discovered during a survey for rust hyperparasites conducted at the Arthur Fungarium, in a single sample from 1912 collected in Trinidad. Macro- and micromorphological descriptions, illustrations, and molecular phylogenetic analyses are presented. The two new species are placed in Trochila with high support in both our six-locus (SSU, ITS, LSU, rpb1 , rpb2 , tef1 ) and two-locus (ITS, LSU) phylogenetic reconstructions. In addition, two species are combined in Trochila : Trochila colensoi (formerly placed in Pseudopeziza ) and T. xishuangbanna (originally described as the only species in Calycellinopsis ). This study reveals new host plant families, a new ecological strategy, and a new country record for the genus Trochila . Finally, our work emphasizes the importance of specimens deposited in biological collections such as fungaria.
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- Award ID(s):
- 2018098
- PAR ID:
- 10250562
- Date Published:
- Journal Name:
- MycoKeys
- Volume:
- 78
- ISSN:
- 1314-4057
- Page Range / eLocation ID:
- 21 to 47
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3897/mycokeys.78.62046
