Volume 5 - 2015 - Issue 1


1. Powdery Mildew (Erysiphaceae) on Calibrachoa hybrids in Germany and the USA

Authors: Brielmaier-Liebetanz U, Field AE, Warfield CY, Braun U

Recieved: 28 January 2015, Accepted: 05 April 2015, Published: 26 May 2015

Cultivated Calibrachoa hybrids were previously thought to be resistant to powdery mildew, but infections have been recently encountered in Germany, USA and Nicaragua. The exclusive development of asexual morphs (anamorphs) led to the question as to which powdery mildew species might be involved as causal agents. Based on inoculation experiments and molecular sequence analyses, it was determined that powdery mildew infections on Calibrachoa in Europe (Germany), North America (USA), and Central America (Nicaragua) were found to be caused by the plurivorous Podosphaera xanthii. The anamorph is a typical Fibroidium characterized by conidia formed in chains (catenescent), containing distinct fibrosin bodies. Calibrachoa powdery mildew caused by P. xanthii could be easily transferred to cucumber, squash and Verbena ×hybrida and vice versa in the latter case. Attempts to inoculate petunias failed. In addition to P. xanthii, two additional powdery mildew species were found infecting Calibrachoa ´hybrida in Germany. The first, characterized by having lobed hyphal appressoria and conidia formed singly, can be assigned to Pseudoidium neolycopersici, and the second species, readily distinguishable by its very long conidiophores, conidia in chains with sinuate outline and nipple-shaped hyphal appressoria, belongs to Euoidium longipes. In the course of the current examinations, E. longipes was also found on Verbena ×hybrida, which represents the first record of this species on a non-solanaceous host.

Keywords: Erysiphales – Euoidium longipes – Podosphaera xanthii – Pseudoidium neolycopersici – Solanaceae – Petunia

 

2. Phytopathogenicity of fungi associated with crown rot of Guava (Psidium guajava)

Authors: Valentino MJG, Pineda FG, Fandialan

Recieved: 26 March 2015, Accepted: 18 May 2015, Published: 28 June 2015

The present study determined the phytopathogenicity of eight species of fungi associated with the crown rot disease of guava fruits. These include Aspergillus flavus, A. fumigatus, A. japonicus var japonicus, A. niger, A. tamarii, Fusarium sambucinum, F. verticillioides and Lasiodiplodia theobromae. The study followed Koch’s postulates for the in vivo infection of guava fruits and re-isolation of taxa for confirmation. Phytopathogenicity testing revealed that Aspergillus flavus, A. fumigatus, A. japonicus, A. niger and A. tamarii, were phytopathogenic causing crown rot of guava. Re-isolation of the phytopathogenic species on the infected plant tissue confirmed the identity of the fungal isolates.

Keywords: crown rot – fungi – guava – Koch’s postulate – pathogen

 

3. Diversity and taxonomy of phytopathogenic Cladosporium on Rubiaceae

Authors: Bhartiya HD, Kumari N, Kumar S, Singh R

Recieved: 17 December 2014, Accepted: 17 May 2015, Published: 28 June 2015

This paper deals with the diversity and taxonomy of phytopathogenic Cladosporium on family Rubiaceaeincludingthe addition of a new species (C. mitragynae) causing foliar disease on Mitragyna pervifolia (Rubiaceae). The present species is described, illustrated and compared with closely related species. This species is distinctly different from earlier reported species having a less developed stroma, shorter conidiophores with less septa and shorter and smooth conidia as compared to previously described species.

Keywords: anamorphic fungi–Cladosporium–foliicolous– new species

 

4. First report of Penicillium purpurogenum causing collar and root rot infection in Aloe vera

Authors: Avasthi S, Gautam AK and Bhadauria R

Recieved: 29 October 2014, Accepted: 18 May 2015, Published: 28 June 2015

Typical symptoms of infection were observed on collar and roots of Aloe vera plants in various nurseries and botanical gardens of Gwalior, Madhya Pradesh, India, mainly during rainy and winter seasons of 2010 and 2011. Infected collar showed dark maroon–brown spots of variable size, while root rot infection appeared in the form of browning and decaying of root tips followed by rotting of total root system. Penicillium purpurogenum was isolated from infected collar and root parts and Koch’s postulates were confirmed. This is the first report of P. purpurogenum causing collar and root rot of Aloe vera in the world.

Keywords: Aloe vera, collar rot, Penicillium purpurogenum, root rot

 

5. New records of Pseudocercospora oenotherae and Synchytrium fulgens on the invasive coastal plant Oenothera laciniata in Taiwan

Authors: Kirschner A

Recieved: 30 October 2014, Accepted: 18 May 2015, Published: 28 June 2015

Oenothera laciniata is a naturalized plant occurring on sand coasts and rural places in Taiwan. Pseudocercospora oenotherae (Dothideomycetes) is first recorded for this host species and for Taiwan. Synchytrium fulgens (Chytridiomycota) is a new record for Taiwan. Descriptions and illustrations are provided for both fungal species. The time spans for spread and detection of introduction of both the host as well as the parasites are discussed.

Keywords: cercosporoid hyphomycetes – introduced species – Onagraceae – sand dune ecology

 

About Plant Pathology & Quarantine

Plant Pathology & Quarantine Online publishes reviews, research articles, methodology papers, and taxonomic works in the field of plant pathology. The official journal language is English.

 

Creative Commons License
Plant Pathology & Quarantine by Plant Pathology & Quarantine is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License

 

 

 

Contact

  • Email:
    ppqjournal@gmail.com



  • Address:
    Department of Plant Pathology
    Agriculture College
    Guizhou University
    Guiyang 550025
    People’s Republic of China