European Journal of Plant Pathology (1996) 102, 795-805

C.L.M. de Visser (1996)
Field evaluation of a supervised control system for Botrytis leaf blight in spring sown onions in the Netherlands
European Journal of Plant Pathology 102 (8), 795-805
Abstract: Between 1988 and 1992 two existing weather based advisory models to control leaf blight in onions, were evaluated in the Netherlands. The first model, BOTCAST, can be used to time the initial spray while the second model, SIV, can be used to advise on every subsequent spraying. The evaluation based on field trials showed that application of both BOTCAST and SIV can reduce the number of sprays by 54% compared to a weekly spraying program without any yield loss or a higher disease severity. There was no relation between yield losses of untreated plots and disease severity expressed as lesion counts or leaf dieback. Relative disease growth rate was significantly but not closely related to weather based model characteristics or the observed crop micro-climate using linear regression analysis. The model characteristics did not yield better regressions than the climatological characteristics. Two changes to improve BOTCAST are proposed. Introduction of a supervised control system based on BOTCAST and SIV seems only economically feasible when the system is used as a regional warning system.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
control - general
thresholds/decision-support systems

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Botrytis squamosa	Onion/garlic/leek (Allium)	Netherlands