Podosphaera pannosa o malura blanca és un fong patogen de les plantes. Produeix l'oïdi a les plantes de la família rosàcia.
És un fong que no penetra dins dels teixits de les plantes. Es combat amb fungicides que incorporen el sofre o altres de síntesi química.
Podosphaera pannosa o malura blanca és un fong patogen de les plantes. Produeix l'oïdi a les plantes de la família rosàcia.
És un fong que no penetra dins dels teixits de les plantes. Es combat amb fungicides que incorporen el sofre o altres de síntesi química.
Der Echte Rosentaupilz (Podosphaera pannosa) ist ein Schlauchpilz aus der Familie der Echten Mehltaupilze (Erysiphaceae). Er ist ein Pflanzenpathogen und befällt vor allem Rosen (Rosa) und Arten der Gattung Prunus.
Das Myzel entwickelt sich schnell kräftig. Es ist zunächst weiß und geht dann nach gelblich bis grau-braun über. Die Konidien sind in Ketten angeordnet. Sie sind 23 bis 29 Mikrometer lang und zwischen 14 und 19 Mikrometer breit. Die Wand der Konidien ist dünn und besteht aus zwei Schichten. Fruchtkörper werden sehr selten gebildet, wenn durchmessen sie zwischen 80 und 100 Mikrometer und enthalten nur wenige Anhängsel.
Der Echte Rosentaupilz wächst auf Zweigen, Blattstielen und Kelchblättern von Rosen oder auf den Triebspitzen von Arten der Gattung Prunus, besonders gerne auf Pfirsich (Prunus persica).
Die Art ist kosmopolitisch (weltweit) verbreitet.
Der Echte Rosentaupilz (Podosphaera pannosa) ist ein Schlauchpilz aus der Familie der Echten Mehltaupilze (Erysiphaceae). Er ist ein Pflanzenpathogen und befällt vor allem Rosen (Rosa) und Arten der Gattung Prunus.
Podosphaera pannosa is a plant pathogen. It produces a powdery mildew on members of the rose family.
Rose powdery mildew [also known as 'Weeping Mildred'] is caused by the fungus Podosphaera pannosa, a member of the Ascomycete fungi. It infects a wide variety of roses, but especially those grown in dryer climates as the fungus has the rare characteristic that not only does it not need water to germinate and reproduce, it can be inhibited by it.[1]
The disease cycle of rose powdery mildew starts when the sexual spores, ascospores, of the pathogen survive the winter in a structure composed of hyphae called an ascocarp. The specific ascocarp is a chasmothecium, or cleistothecium, and has a circular shape to it. Under the right conditions the chasmothecium will break open to reveal the asci, which are long tube-like structures containing the ascospores. These ascospores are then released and spread by wind, insects, and rain until they land on a susceptible rose for a host and land, attach, and germinate on the plant. They will also produce condia, the asexual spores of Podosphaera pannosa, which will spread throughout the summer. It is these long chains of white conidia which give the fungus its characteristic “powdery” appearance. Late in the year as the plant is dying cleistothecia will again form when the ascogonium receives the nucleus from the antheridium.[1]
Optimal conditions for rose powdery mildew are 16-27 degrees Celsius, with the optimal temperature for fungal growth at 23 degrees Celsius in a shaded area.[1][2] They also do not need water to germinate and infect the rose. In fact, if there is too much water present on plant surfaces for a prolonged period of time the fungal growth is inhibited and the spores can actually die. Rose powdery mildew can also grow in any conditions where roses can grow and has been found everywhere from China to the United States.[1]
A wide variety of rose species are susceptible to powdery mildew. In light of this it is more practical to discuss the rose varieties that are resistant as opposed to those that are susceptible. Two varieties that have been found to show resistance to rose powdery mildew are "Paul's Pink" rose variety and the "Magic" rose variety.[3] Other research has shown that many chestnut rose (Rosa roxburghii) varieties are also resistant to powdery mildew. Rosa sterilis, Rosa kweichowensis, Rosa laevigata, Rosa lucidissima, and Rosa chinensis have all been shown to be resistant to powdery mildew. R. multiflora var. multiflora and R. multiflora var. cathayensis have all been shown to be susceptible to rose powdery mildew.[4] Symptoms caused by the rose powdery mildew can be a dwarfing of the growth of the plant, or the twisting and deforming of leaves,[5] but more noticeable is a sign of the disease, which is the white condia, the “powder” that appears on the plant surfaces, such as leaves, shoots, flowers, and buds.[1] The fungus may grow on both new and old leaves, but is generally more concentrated on the underside of the leaf [6]
Effective management of rose powdery mildew begins by using resistant varieties of rose, but it can also be managed through the use of fungicides, or by planting in sun since rose powdery mildew prefers the shade.[1] In fact, increasing the exposure of rose powdery mildew from 18 to 24 hours of light per day reduced the production of conidia, the asexual spores of the fungus, by as much as 62%.[7] There are a variety of fungicides that have proven to be effective. Examples are myclobutanil, azoxystrobin, triadimefon, and thiophanate-methyl formulations [8] Chemical fungicides are not always necessary, however, it is possible to use more environmentally-friendly solutions such as a water-vinegar spray, or mixtures of baking soda and insecticidal soaps [9] Recent studies have also shown that using a planting medium which includes silicon can also reduce the occurrence of powdery mildew by as much as 57% [10]
Powdery mildew affects more the 7600 species of hosts worldwide, including subsistence crops [11] Although rose powdery mildew will most directly affect the rose connoisseur, it is part of this larger family of powdery mildews, which can affect the crops used for food and survival in many countries, thereby having economic and human impacts beyond that of an unsightly rose bush. Research shows that total yield loss from powdery mildew on cereal crops alone can vary anywhere between 2 and 30% depending on the host and the environmental conditions.[12] Additionally, the wholesale value of roses annually exceeds $100 million in the United States, so the national economic impact from the flower industry cannot be ignored [13] As explained by an old gardener's adage 'Weeping Mildred! She's no friend of the gardener and certainly no friend of me'.
Podosphaera pannosa on Rosa sp. leaf 
Podosphaera pannosa Podosphaera pannosa is a plant pathogen. It produces a powdery mildew on members of the rose family.
Podosphaera pannosa es un hongo muy extendido, siendo una de las enfermedades más ampliamente distribuidas en los jardines ornamentales , resultando fácil de reconocer debido a las inconfundibles manchas pulverulentas que crea. Afecta principalmente a roble europeo, vid, rosal, evónimo, plátano, begonia, duraznero, siendo relativamente importante sus ataques a especies forestales. Este pequeño hongo procura la muerte del tejido que ataca, pero no invade la planta, ya que es, en esencia de acción superficial.
Podosphaera pannosa est une espèce de champignons ascomycètes de la famille des Erysiphaceae.
Ce champignon est responsable, parfois en concomitance avec d'autres espèces de la même famille, de diverses formes d'oïdium, notamment l'oïdium du pêcher et l'oïdium du rosier.
Ce champignon a une répartition cosmopolite[2].
Ce champignon, comme d'autres espèces de l'ordre des Erysiphales, est parasité par un autre champignon ascomycète, Ampelomyces quisqualis de la famille des Phaeosphaeriaceae (ordre des Pleosporales), qui est un hyperparasite et qui a fait l'objet depuis 50 ans de nombreuses études en vue de son utilisation en lutte biologique[3].
Selon Catalogue of Life (10 octobre 2014)[1] :
La gamme de plantes hôtes infectées naturellement comprend divers arbres et arbustes de la famille des Rosaceae : genre Prunus (dont Prunus dulcis (amandier), Prunus armeniaca (abricotier), Prunus cerasus (cerisier), Prunus laurocerasus (laurier-cerise), Prunus persica (pêcher), Prunus salicina (prunier du Japon) et genre Rosa spp (dont Rosa canina (églantier), Rosa damascena (rosier de Damas), Rosa foetida et Rosa moschata (rosier musqué), ainsi que d'autres familles botaniques, dont Catharanthus roseus (pervenche de Madagascar), Cotinus coggygria (fustet), Eucalyptus, Forsythia, Rhododendron (rhododendrons et azalées)[4].
Podosphaera pannosa est une espèce de champignons ascomycètes de la famille des Erysiphaceae.
Ce champignon est responsable, parfois en concomitance avec d'autres espèces de la même famille, de diverses formes d'oïdium, notamment l'oïdium du pêcher et l'oïdium du rosier.
Ce champignon a une répartition cosmopolite.
Ce champignon, comme d'autres espèces de l'ordre des Erysiphales, est parasité par un autre champignon ascomycète, Ampelomyces quisqualis de la famille des Phaeosphaeriaceae (ordre des Pleosporales), qui est un hyperparasite et qui a fait l'objet depuis 50 ans de nombreuses études en vue de son utilisation en lutte biologique.
Sphaerotheca pannosa è una specie di funghi appartenente alla classe degli Ascomiceti, ordine Perisporiales, famiglia Erisiphaceae. È l'agente dell'oidio o mal bianco del pesco e della rosa. Sulla pagina superiore delle foglie si sviluppa una muffa biancastra; successivamente le foglie si deformano e poi si disseccano e cadono. Oltre alle foglie, il patogeno può colpire anche i giovani rametti e i frutticini in via di accrescimento. La lotta va condotta con interventi meccanici (asportazione degli organi colpiti) e trattamenti chimici con anticrittogamici.
Podosphaera pannosa (Wallr.) de Bary – gatunek grzybów należący do rzędu mączniakowców (Erysiphales)[1]. Wywołuje chorobę o nazwie mączniak prawdziwy róży[2].
Pozycja w klasyfikacji według Index Fungorum: Podosphaera, Erysiphaceae, Erysiphales, Leotiomycetidae, Leotiomycetes, Pezizomycotina, Ascomycota, Fungi[1].
Po raz pierwszy zdiagnozował go w 1819 r. C.F Wallroth nadając mu nazwę Alphitomorpha pannosa. Obecną, uznaną przez Index Fungorum nazwę nadał mu w 1870 r. H.A de Bary.
Grzybnia trwała, gęsta, rozpostarta, biała lub szara zbudowana z gęsto splątanych strzępek o szerokości 3–7 μm. Strzępki są słabo rozgałęzione z przegrodami. Pierwszy człon konidioforu wyprostowany, prosty, niemal cylindryczny, o długości 45–80 μm i szerokości 7,5–12 μm. Powyżej pierwszego członu jest jeszcze 1–2 krótszych. Zarodniki konidialne typu oidium w łańcuchach. Są bezbarwne, elipsoidalno-jajowate, o rozmiarach 20–33 × 12–19 μm. Appressorium brodawkowate. Klejstotecja w grupach, zanurzone w grzybni, liczniejsze na łodygach porażonych roślin, zwłaszcza koło cierni. Mają kulisty lub gruszkowaty kształt i szerokość 80–120 μm. Zbudowane są z komórek o wielokątnym, nieregularnym kształcie. Mają kilka wąskich, bezbarwnych lub lekko jasnobrązowych przyczepek, krótszych niż średnica klejstotecjum. Worki podłużne półowalne, o rozmiarach 60–75 × 80–100 μm. Powstaje w nich po 8 owalnych, bezbarwnych askospor o rozmiarach 20–30 × 12–17 μm[4].
Jest szeroko rozprzestrzeniony. Występuje we wszystkich regionach świata, w których występują róże[4].
Pasożyt rozwijający się na wielu gatunkach róż (Rosa) i niektórych gatunkach śliw (Prunus). Wiele gatunków i kultywarów róż wykazuje odporność[4]. W Polsce zarejestrowano występowanie tego patogenu na następujących gatunkach: Persica vulgaris, Prunus domestica, Rosa agrestis, Rosa canina, Rosa × centifolia, Rosa dumalis, Rosa gallica, Rosa glauca, Rosa multiflora, Rosa pendulina, Rosa polyantha, Rosa rubiginosa, Rosa rugosa, Rosa sclerophylla, Rosa tomentosa, Rosa villosa oraz uprawiane kultywary róż[5].
Podosphaera pannosa (Wallr.) de Bary – gatunek grzybów należący do rzędu mączniakowców (Erysiphales). Wywołuje chorobę o nazwie mączniak prawdziwy róży.
Podosphaera pannosa je grzib[14], co go nojprzōd ôpisoł Carl (Karl) Friedrich Wilhelm Wallroth, a terŏźnõ nazwã doł mu de Bary 1870. Podosphaera pannosa nŏleży do zorty Podosphaera i familije Erysiphaceae.[15][16] Żŏdne podgatōnki niy sōm wymianowane we Catalogue of Life.[15]
Podosphaera pannosa je grzib, co go nojprzōd ôpisoł Carl (Karl) Friedrich Wilhelm Wallroth, a terŏźnõ nazwã doł mu de Bary 1870. Podosphaera pannosa nŏleży do zorty Podosphaera i familije Erysiphaceae. Żŏdne podgatōnki niy sōm wymianowane we Catalogue of Life.
Sphaerotheca pannosa là một loài Ascomycetes trong họ Erysiphaceae. Loài này được Wallr. Lev miêu tả khoa học đầu tiên năm 1851.[1]
Đây là loài gây hại phát triển phổ biến ở Uzbekistan.
Sphaerotheca pannosa là một loài Ascomycetes trong họ Erysiphaceae. Loài này được Wallr. Lev miêu tả khoa học đầu tiên năm 1851.
Đây là loài gây hại phát triển phổ biến ở Uzbekistan.
