Summa Phytopathologica (2010) 36, 35-39

Maria Isabel Balbi-Peña, Kátia Regina Freitas Schwan-Estrada, José Renato Stangarlin and João Batista Tolentino Júnior (2010)
Desenvolvimento de Oidium neolycopersici em genótipos do gênero Lycopersicon
[Development of Oidium neolycopersici on Lycopersicon genotypes]
Summa Phytopathologica 36, 35-39
Abstract: Tomato powdery mildew, caused by Oidium neolycopersici, is a common disease of tomato, especially in greenhouse conditions. To investigate the nature of powdery mildew resistance, we studied the histopathology of the infection process in six different tomato genotypes: CNPH 416, CNPH 423, CNPH 1287 (Lycopersicon hirsutum), CNPH 0081 (L. esculentum var. cerasiforme), cv. Santa Cruz Kada e cv. Santa Clara (L. esculentum). Leaf discs of the 3rd, 4th and 5th leaves from plants with 5-7 true leaves were placed on water agar in Petri dishes, inoculated using fresh sporulating mycelium of tomato powdery mildew and incubated at 19-22ºC, 4000 lx and 12h photoperiod. After clearing with boiling ethanol, the discs were microscopically examined at 19 h, 8 and 9 days post inoculation to evaluate germ tube development, sporulation and disease severity. Conidial germination on foliar tissue was similar in all genotypes. Secondary hypha, appresoria and haustoria per germinated conidia were lowest in CNPH 1287 and 423, which also exhibited the lowest sporulation and disease severity. L. esculentum and L.esculentum var. cerasiforme genotypes showed the highest mildew susceptibility and CNPH 416 showed intermediate susceptibility. Powdery mildew resistance of CNPH 1287 and CNPH 423 was already evident at 19 hours after inoculation based upon the lower percentage of secondary hypha, appresoria and haustoria observed than in the susceptible ones.
(The abstract has been supplied by the author or ISPI and is excluded from the Creative Commons licence.)
(original language: Portuguese)
Link to article at publishers website
Database assignments for author(s): Maria Isabel Balbi-Peña

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Pseudoidium neolycopersici	Tomato (Solanum lycopersicum)