scholarly journals Golovinomyces orontii and other powdery mildews on Rosmarinus officinalis

2012 ◽  
Vol 2 (2) ◽  
pp. 162-166 ◽  
Author(s):  
A. Wichura
Plant Disease ◽  
2007 ◽  
Vol 91 (5) ◽  
pp. 632-632
Author(s):  
A. Garibaldi ◽  
D. Bertetti ◽  
M. L. Gullino

Petunia × hybrida (Solanaceae) includes several hybrids that are grown as ornamental plants and are very much appreciated for their long-lasting flowering period. Among those, the variety pendula is often selected because of its hanging growth habit that is favorable for balcony decoration. During the summer of 2005, severe outbreaks of a previously unknown powdery mildew were observed on all petunia plants in several gardens near Biella and Torino (northern Italy). Both surfaces of the leaves of affected plants were covered with white, dense mycelia and conidia. As the disease progressed, infected leaves turned yellow and died. Mycelia also were observed on stems and flowers. Conidia were hyaline, ellipsoid, borne in short chains (with a maximum of four conidia per chain), and measured 27 to 36 × 17 to 21 μm (average 31 × 19 μm). Conidiophores, 130 to 154 μm (average 140 μm) long, showed the foot cell (measuring 42 to 65 × 10 to 12 μm, average 52 × 11 μm) followed by three shorter cells measuring 27 to 30 × 13 to 17 μm (average 29 to 14 μm). Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 (3) and sequenced. BLASTn analysis (1) of the 588 bp obtained showed an E-value of 0.0 with Golovinomyces orontii (Erysiphe orontii) (2). The nucleotide sequence has been assigned GenBank Accession No. DQ 987491. Inoculations were made by gently pressing diseased leaves onto leaves of five healthy Petunia × hybrida var. pendula plants, belonging to cv. Surfinia. Five noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a greenhouse at temperatures between 14 and 30°C. After 10 days, typical powdery mildew symptoms developed on inoculated plants. Noninoculated plants did not show symptoms. The pathogenicity test was carried out twice. To our knowledge, this is the first report of the presence of powdery mildew on P. × hybrida caused by G. orontii in Italy. A powdery mildew of P. × hybrida reported in 1966 in Romania has been attributed to E. cichoracearum (4), while Braun (2) reported P. × hybrida as a possible host of E. orontii. Specimens of this disease are available at AGROINNOVA Collection, University of Torino, Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) U. Braun. A Monograph of the Erysiphaceae (Powdery Mildews). Cramer, Berlin, GDR, 1987. (3) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) E. Eliade. Reprium nov. Spec. Regni veg.73:43, 1966.


Plant Disease ◽  
2007 ◽  
Vol 91 (5) ◽  
pp. 635-635 ◽  
Author(s):  
A. Garibaldi ◽  
D. Bertetti ◽  
D. Minerdi ◽  
M. L. Gullino

Lamium galeobdolon L. (Labiatae) is a common ornamental species that grows in shade areas and often used as a ground cover in gardens. During the summer of 2006, severe outbreaks of a previously unknown powdery mildew were observed on all Lamium spp. plants in some gardens near Biella (northern Italy). Both surfaces of the leaves of affected plants were covered with dense, white mycelia and conidia. As the disease progressed, infected leaves turned yellow and died. Mycelia and conidia also were observed on stems and flowers. Conidia were hyaline, ellipsoid, borne in short chains (with a maximum of five conidia per chain), and measured 29 to 37 × 16 to 20 μm (average 33 × 18 μm). Conidiophores, 91 to 104 μm (average 96 μm) long, showed the foot cell measuring 28 to 49 × 9 to 11 μm (average 38 × 10 μm), followed by three shorter cells measuring 14 to 26 × 9 to 15 μm (average 21 × 11 μm). Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer region (ITS) of rDNA was amplified using the primers ITS4/ITS6 (4) and sequenced. BLASTn analysis (1) of the 436 bp obtained showed an E-value of 0.0 with Golovinomyces orontii (Erysiphe orontii.) (3). The nucleotide sequence has been assigned GenBank Accession No. EF 121871. Inoculations were made by gently pressing diseased leaves onto leaves of five healthy L. galeobdolon plants. Five noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a greenhouse at temperatures between 15 and 28°C. After 10 days, typical powdery mildew colonies developed on inoculated plants. Noninoculated plants did not show symptoms. The pathogenicity test was carried out twice. To our knowledge, this is the first report of the presence of powdery mildew on L. galeobdolon caused by G. orontii in Italy. Blumer (2) was able to reproduce powdery mildew symptoms on L. galeobdolon using populations from cucumber, while Braun (3) reported L. galeobdolon as a possible host of E. orontii. Herbarium specimens of this disease are available at AGROINNOVA Collection, University of Torino, Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) S. Blumer. Ber. Schweiz. Bot. Ges. 62:384, 1952. (3) U. Braun. A Monograph of the Erysiphaceae (Powdery Mildews). Cramer, Berlin, GDR, 1987. (4) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997.


Author(s):  
John S. Gardner ◽  
W. M. Hess

Powdery mildews are characterized by the appearance of spots or patches of a white to grayish, powdery, mildewy growth on plant tissues, entire leaves or other organs. Ervsiphe cichoracearum, the powdery mildew of cucurbits is among the most serious parasites, and the most common. The conidia are formed similar to the process described for Ervsiphe graminis by Cole and Samson. Theconidial chains mature basipetally from a short, conidiophore mother-cell at the base of the fertile hypha which arises holoblastically from the conidiophore. During early development it probably elongates by polar-tip growth like a vegetative hypha. A septum forms just above the conidiophore apex. Additional septa develop in acropetal succession. However, the conidia of E. cichoracearum are more doliform than condia from E. graminis. The purpose of these investigations was to use scanning electron microscopy (SEM) to demonstrate the nature of hyphal growth and conidial formation of E. cichoracearum on field-grown squash leaves.


Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
A Altintas ◽  
F Göger ◽  
HG Duymuş ◽  
N Kırımer ◽  
KHC Başer

2019 ◽  
Vol 2 (2) ◽  
pp. 16
Author(s):  
Eloisa Lorenzetti ◽  
Dablieny Hellen Garcia Souza ◽  
Juliano Tartaro ◽  
José Renato Stangarlin ◽  
Gilberto Costa Braga

A banana apresenta elevada suscetibilidade a doenças como as podridões que diminuem o tempo de prateleira do fruto. Uma das formas de controlar as doenças seria a utilização de métodos alternativos como os extratos de plantas medicinais. Assim, o objetivo deste estudo foi verificar a ação de formulados de alecrim (Rosmarinus officinalis L.) pó e líquido no controle de antracnose causada pelo fungo Colletotrichum musae (Berk & Curt.) Von Arx. e na maturação de banana ‘Nanicão’ em pós-colheita. Foram utilizadas as concentrações 0%; 0,25%; 0,5%; 1%; 1,5% e 2% do pó solúvel de extrato de alecrim diluído em água destilada, e as concentrações 0%; 0,5%; 1%; 2%; 4% e 6% do formulado aquoso contendo 21% de resíduo seco de alecrim diluído em água destilada. Foi realizada a mensuração da área de cada fruto e avaliada a severidade e a maturação a partir de porcentagem de área dos frutos, sendo os resultados utilizados para calcular a área abaixo da curva de progresso da doença (AACPD) e a porcentagem de maturação dos frutos. Realizou-se analise de regressão a partir dos dados obtidos e pode-se verificar que para o formulado de alecrim em pó a AACPD reduziu mais de 29% e para a maturação a redução foi de 21,72%. Para o formulado líquido a redução foi de 14,31% para AACPD e cerca de 10% para maturação. Assim, concluiu-se que houve eficiência por parte dos formulados de alecrim no controle da antracnose e no aumento da vida de prateleira da banana ‘Nanicão’.


2019 ◽  
pp. 05-09

The presence study deals with powdery mildews in various cucurbits in Katsina city (Barhim Estate, Kofar Durbi, Kofar Sauri, Kofar Marusa and Low Cost), Nigeria. The finding shows that the areas infested with powdery mildew is one of the important disease of cucurbits. The Sphaerotheca fuliginea was identified to be the causal organism present on all observed cucurbits in the study. Highest frequency of disease was found in Kofar Sauri(79%) fallowed by Kofar Marusa (68%), Kofar Durbi (66%), Barhim Estate (65%) and the lowest frequency of occurrence of disease was found in Low Cost (55%).The intensity of the disease was moderate to severe in general but it was high in many fields, the area-wise variation was also noticed. On vegetables, the highest frequency of occurrence of powdery mildew disease was observed on L. cylindrica (76.4%) followed by C. moschata (60%), C. sativus (59.3%), C. vulgaris (53.9%) and lowest was found on C. melo (44.4%). The highest intensity of disease was found on C. moschata, followed by L. cylindrica, C. sativus, C. vulgaris and C. melo.


2019 ◽  
Vol 18 (5) ◽  
pp. 321-339 ◽  
Author(s):  
M. Slighoua ◽  
I. Mahdi ◽  
F. Ez-zahra Amrati ◽  
S. Boukhira ◽  
A. EL Hamsas EL Youbi ◽  
...  

An ethnopharmacological survey was carried out among 224 informants to collect the information on medicinal plants used for the traditional treatment of female infertility in the Fes, Meknes and Boulemane region. In total, 63 plant species belonging to 29 families were used against female infertility. The most frequently cited plants were Lavandula officinalis (26.33%), Mentha pulegium (13.83%), Mentha suaveolens (11.16%), Rosmarinus officinalis (10.71%) and Petroselinum sativum (8.03%). Furthermore, the present study represents a useful documentation for the preservation of this knowledge about medicinal plants and for the amelioration of women reproductive health.


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