Biology:Peronospora
| Peronospora | |
|---|---|
| |
| P. manshurica on soybean leaf | |
Scientific classification 
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| Domain: | Eukaryota |
| Clade: | Diaphoretickes |
| Clade: | SAR |
| Clade: | Stramenopiles |
| Phylum: | Oomycota |
| Order: | Peronosporales |
| Family: | Peronosporaceae |
| Genus: | Peronospora Corda |
Peronospora is a genus of oomycetes that are obligate plant pathogens of many eudicots.[1] Most species in this group produce a downy mildew disease, which can cause severe damage to many different cultivated crops, as well as wild and ornamental plants.[2] There are 19 genera that produce downy mildew, and Peronospora has been placed alongside Pseudoperonospora in the group of downy mildews with coloured conidia.[3] Peronospora has far more species than any other genus of the downy mildews.[3] However, many species have been moved from this genus to be reclassified to other or new genera.[4] Among these was the most famous Peronospora species, formerly known as Peronospora parasitica, and now known as Hyaloperonospora parasitica.[4] Now, the Peronospora species of most importance is likely the Peronospora tabacina.[5] Peronospora tabacina causes blue mold on tobacco plants and can severely reduce yields of this economically important crop to the point where it has been classified as a bioweapon.[5][3]
History
Peronospora was first described in 1837 by August Carl Joseph Corda, a Czech mycologist and physician, in his first of six volumes of his Icones fungorum hucusque cognitorum.[6] Since then, many of the species originally placed in Peronospora have been allocated to other genera or given rise to new genera based on new techniques such as molecular genetics.[4]
There was an epidemic in 1960 of Peronospora tabacina affecting tobacco plants leading to $25 million in losses across eleven countries, which was about 30 percent of the tobacco plants.[5] Another epidemic that was caused by Peronospora destructor reduced the yield of sweet onions by 25 percent in Georgia, USA in 2012, and led to an estimated $18.2 million in losses.[7]
Habitat and ecology
Most of the Peronospora species are highly specific to their hosts and can generally be found anywhere the host plant grows, or is being cultivated.[3] A large portion of their life cycle is spent inside their host plant. Many species of Peronospora are seedborne pathogens, so the worldwide spread of Peronospora crop-plant pathogens is likely to be a result of unknowingly trading infected seeds to new areas.[3] There are also many Peronospora species that are spread by wind currents, which allows them to disperse over large distances.[3] Peronospora species prefer humid air and cool temperatures.[5]
General form and structure
The first stage in the Peronospora life history is the sporangia.[5] The sporangia are small spore-like structures about 65 um long that germinate a germ-tube when they are near a leaf stoma.[8][5] A germ tube will come from the sporangium and penetrate the leaf cell where it will form a haustorium.[5] The haustorium absorbs nutrients from the leaf, while hyphae invade the intercellular space, and the leaf will eventually develop a lesion.[5] These lesions often start out yellow and then turn brown as the leaf starts to undergo necrosis.[5] From here, Peronospora can undergo either asexual reproduction or sexual reproduction.[5] Asexual reproduction occurs when the air outside is moist making for favourable conditions.[5] During asexual reproduction, hyphae on the host plant will form sporangiophores, which will produce conidia.[5] The conidia will be dispersed by the wind is able to infect other plants.[5] The asexual cycle only takes five to seven days to complete.[5] Sexual reproduction occurs when the conditions are unfavourable and it needs to withstand harsh environmental conditions.[5] During sexual reproduction, the hyphae will undergo meiosis forming antheridia and oogonia, the only haploid structures in the Peronospora life history.[5] The antheridia will fuse to the oogonia, initiating plasmogamy and then karyogamy, and will result in the production of many oospores.[5] The oospores can then be dispersed by the wind to infect more plants.[5]
Both Peronospora and Pseudoperonospora are characterized by their ability to produce melanized sporangia, but Pseudoperonospora produces zoospores whereas Peronospora cannot.[3]
Practical importance
The model oomycete pathogen, Peronospora parasitica, used to be included in this genus, however it has been reclassified to the genus Hyaloperonospora.[3]
Some species of Peronospora have been considered for their use as a bioweapon or have been classified as potential bioweapons.[3] Peronspora somniferi was considered for its ability to devastate fields of the opium poppy, which could have targeted areas that depend on the crop.[3] The United States has classified Peronospora tabacina as a possible bioweapon, because if it were used to target the US tobacco industry, it would lead to major economic loss.[3]
Genomics and genetics
Only one species in the genus Peronospora has had its genome sequenced and assembled. In 2015, Derevnina et al. performed a de novo sequence assembly of the genome of two Peronospora tabacina isolates using Illumina sequencing.[9] They estimated the genome size to be 68 Mb with a mitochondrial genome of 43 kb.[9] The two assemblies had 61.8x and 128.9x coverage for the nuclear genomes and 6,824x and 43,225x coverage for the mitochondrial genomes.[9] The mitochondrial genome only differed by seven single nucleotide polymorphisms, three small indels, and one copy number variant.[9] Using a program to predict gene models, they found 18,000 potential protein coding genes.[9]
List of species
The following species are placed in genus Peronospora:[10]
- Peronospora aconiti
- Peronospora aestivalis
- Peronospora affinis
- Peronospora agrestis
- Peronospora agrimoniae
- Peronospora alchemillae
- Peronospora alpicola
- Peronospora alsinearum
- Peronospora alta Fuckel
- Peronospora akatsukae Ito & Murayama
- Peronospora anagallidis
- Peronospora antirrhini
- Peronospora aparines
- Peronospora apula
- Peronospora aquatica
- Peronospora arborescens
- Peronospora arenariae
- Peronospora argemones
- Peronospora arthurii
- Peronospora arvensis
- Peronospora asperuginis
- Peronospora astragalina
- Peronospora atriplicis-hastatae
- Peronospora belbahrii
- Peronospora boni-henrici
- Peronospora bulbocapni
- Peronospora calotheca
- Peronospora campestris
- Peronospora canescens Benua
- Peronospora cerastii-anomali
- Peronospora cerastii-brachypetali
- Peronospora chenopodii-polyspermi
- Peronospora chlorae
- Peronospora chrysosplenii
- Peronospora claytoniae
- Peronospora conglomerata
- Peronospora consolidae
- Peronospora coronillae
- Peronospora corydalis
- Peronospora corydalis-intermediae
- Peronospora cristata
- Peronospora cyparissiae
- Peronospora debaryi
- Peronospora destructor
- Peronospora dianthi
- Peronospora dianthicola
- Peronospora dicentrae
- Peronospora digitalis
- Peronospora dipsaci
- Peronospora echii
- Peronospora effusa
- Peronospora elsholtziae
- Peronospora erodii
- Peronospora ervi
- Peronospora esulae
- Peronospora farinosa
- Peronospora farinosa f. sp. betae
- Peronospora farinosa f. sp. chenopodii
- Peronospora farinosa f. sp. spinaciae
- Peronospora ficariae
- Peronospora flava
- Peronospora fulva
- Peronospora galii
- Peronospora glechomae
- Peronospora grisea
- Peronospora hiemalis
- Peronospora holostei
- Peronospora honckenyae
- Peronospora illyrica
- Peronospora jagei
- Peronospora knautiae
- Peronospora kochiae-scopariae
- Peronospora lamii
- Peronospora lapponica
- Peronospora lathyri-verni
- Peronospora lathyrina
- Peronospora lepigoni
- Peronospora linariae
- Peronospora linariae-genistifoliae
- Peronospora lithospermi
- Peronospora litoralis
- Peronospora lotorum
- Peronospora manshurica
- Peronospora mayorii
- Peronospora meconopsidis
- Peronospora medicaginis-minimae
- Peronospora medicaginis-orbicularis
- Peronospora melandryi-noctiflori
- Peronospora meliloti
- Peronospora mesembryanthemi
- Peronospora minor
- Peronospora myosotidis
- Peronospora narbonensis
- Peronospora oblatispora
- Peronospora obovata
- Peronospora ornithopi
- Peronospora orobi
- Peronospora parva
- Peronospora paula
- Peronospora perillae
- Peronospora phacae
- Peronospora plantaginis
- Peronospora polycarpi
- Peronospora polygoni
- Peronospora polygoni-convolvuli
- Peronospora potentillae
- Peronospora potentillae-anserinae
- Peronospora potentillae-reptantis
- Peronospora potentillae-sterilis
- Peronospora pseudostellaria
- Peronospora pulveracea
- Peronospora radii
- Peronospora ranunculi
- Peronospora aff. ranunculi
- Peronospora romanica
- Peronospora rubi
- Peronospora rumicis
- Peronospora salviae-plebeiae
- Peronospora sanguisorbae
- Peronospora saturejae-hortensis
- Peronospora saxifragae
- Peronospora schachtii
- Peronospora scleranthi
- Peronospora scutellariae
- Peronospora sepium
- Peronospora sherardiae
- Peronospora silvatica
- Peronospora silvestris
- Peronospora somniferi
- Peronospora sordida
- Peronospora sparsa
- Peronospora stachydis
- Peronospora statices
- Peronospora stellariae-aquaticae
- Peronospora stellariae-uliginosae
- Peronospora stigmaticola
- Peronospora swinglei
- Peronospora symphyti
- Peronospora tabacina
- Peronospora tetragonolobi
- Peronospora teucrii
- Peronospora tomentosa
- Peronospora tranzscheliana
- Peronospora trifolii-alpestris
- Peronospora trifolii-arvensis
- Peronospora trifolii-hybridi
- Peronospora trifolii-minoris
- Peronospora trifolii-repentis
- Peronospora trifoliorum
- Peronospora trifoliorum f. trifolii-pratensis
- Peronospora trigonellae
- Peronospora trigonotidis
- Peronospora trivialis
- Peronospora valerianae
- Peronospora valerianellae
- Peronospora variabilis
- Peronospora verbasci
- Peronospora verbenae
- Peronospora verna
- Peronospora vernalis
- Peronospora viciae
- Peronospora viciae f. sp. pisi
- Peronospora violacea
- Peronospora violae
References
- ↑ Göker, M., García-Blázquez, G., Voglmayr, H., Tellería, M. T., & Martín, M. P. (2009). "Molecular taxonomy of phytopathogenic fungi: a case study in Peronospora.". PLOS ONE 4 (7): e6319. doi:10.1371/journal.pone.0006319. PMID 19641601. Bibcode: 2009PLoSO...4.6319G.
- ↑ Lee, J. S., Shin, H. D., Lee, H. B., & Choi, Y. J. (2017). "Taxonomy and Phylogeny of Peronospora Species (Oomycota) Parasitic to Stellaria and Pseudostellaria in Korea, with the Introduction of Peronospora casparyi sp. nov.". Mycobiology 45 (4): 263–269. doi:10.5941/MYCO.2017.45.4.263. PMID 29371794.
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 Thines, M., & Choi, Y. J. (2015). "Evolution, diversity, and taxonomy of the Peronosporaceae, with focus on the genus Peronospora". Phytopathology 106 (1): 6–18. doi:10.1094/PHYTO-05-15-0127-RVW. PMID 26649784.
- ↑ 4.0 4.1 4.2 Göker, M., Voglmayr, H., Riethmüller, A., Weiß, M., & Oberwinkler, F. (2003). "Taxonomic aspects of Peronosporaceae inferred from Bayesian molecular phylogenetics". Canadian Journal of Botany 81 (7): 672–683. doi:10.1139/b03-066.
- ↑ 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 5.11 5.12 5.13 5.14 5.15 5.16 5.17 Krsteska, V., Dimeska, V., Stojkov, S., & Stojanoski, P. (2015). "Peronospora tabacina A. the causing agent of Blue Mold disease on tobacco.". Bulgarian Journal of Agricultural Science 21: 132–139. http://eprints.uklo.edu.mk/312/.
- ↑ Corda, A. C. J. (1837). Icones fungorum hucusque cognitorum, vol. 1.
- ↑ Parkunan, V., Gitaitis, R. D., Dutta, B., Langston, D. B., & Ji, P. (2013). "An Epidemic of Downy Mildew caused by Peronospora destructor on Vidalia Sweet Onions in Georgia in 2012.". Plant Health Progress 14: 54. doi:10.1094/PHP-2013-0328-01-BR.
- ↑ Langston Jr, D. B., & Sumner, D. R. (2000). "First report of downy mildew (caused by Peronospora destructor) of onion in Georgia". Plant Disease 84 (4): 489. doi:10.1094/PDIS.2000.84.4.489B. PMID 30841183.
- ↑ 9.0 9.1 9.2 9.3 9.4 Derevnina, L., Chin-Wo-Reyes, S., Martin, F., Wood, K., Froenicke, L., Spring, O., & Michelmore, R. (2015). "Genome sequence and architecture of the tobacco downy mildew pathogen Peronospora tabacina". Molecular Plant-Microbe Interactions 28 (11): 1198–1215. doi:10.1094/MPMI-05-15-0112-R. PMID 26196322.
- ↑ "Taxonomy Browser: Peronospora ". https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=70742&lvl=3&keep=1&srchmode=1&unlock.
Wikidata ☰ Q1650703 entry
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