Plant Pathology (2006) 55, 664-670

Y. Zhao, B.W. Grout and X. Xu (2006)
Effects of temperature on germination and hyphal growth from conidia of Ramularia rhei and Ascochyta rhei, causing spot diseases of rhubarb (Rheum rhaponticum)
Plant Pathology 55 (5), 664-670
Abstract: Rhubarb leaf and petiole spot disease, caused by Ramularia rhei and Ascochyta rhei, has gradually become more noticeable in the UK field crop. Conidial germination and subsequent colony growth of R. rhei and A. rhei were investigated under in vitro conditions on potato dextrose agar and in vivo on leaf discs. Results indicated that the two fungi responded differently to temperature. Ramularia rhei was better adapted to temperatures < 25°C, with an optimum around 20°C, whereas A. rhei was more adapted to temperatures > 15°C, with an optimum > 25°C. Overall, conidia of R. rhei germinated and subsequent colonies grew at greater rates than those of A. rhei on leaf discs at temperatures < 25°C. These results indicated that it is important to identify the causal agent of leaf and petiole spot diseases in rhubarb field crops in order to estimate disease risks accurately.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: English)
Link to article at publishers website
Database assignments for author(s): Xiang Ming Xu

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
rearing/culturing/mass production

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Ramularia pratensis	Rhubarb (Rheum)	United Kingdom
	Didymella rhei	Rhubarb (Rheum)	United Kingdom