HortScience (2014) 49, 1392-1396

Jaimin S. Patel, Shouan Zhang and Maria I. Costa de Novaes (2014)
Effect of plant age and acibenzolar-s-methyl on development of downy mildew of basil
HortScience 49 (11), 1392-1396
Abstract: Sweet basil (Ocimum basilicum) is an important annual culinary herb grown in the United States. Recently, basil production was drastically affected by downy mildew caused by Peronospora belbahrii, a recently discovered foliar disease of basil in Homestead, FL. The disease has spread to more than 30 states in the United States causing significant losses to basil growers. As a result of the recent emergence of the disease, limited management tools are available for control of downy mildew, and it is critical for growers to apply management measures at appropriate times. This study was designed to evaluate 2- to 7-week-old basil plants for their susceptibility to downy mildew. Another objective of the study was to evaluate the effect of a pre-inoculation application of acibenzolar-S-methyl (ASM) for control of downy mildew. The results suggested that 2- to 3-week-old basil was more susceptible to downy mildew than 4- to 7-week-old plants. The area under the disease progress curve (AUDPC) was smaller for 5- to 7-week-old ASM-treated basil plants than for 2- to 4-week-old ASM-treated basil plants. This study indicated that 2- to 3-week-old basil plants need to be protected, and ASM should be applied before pathogen infection on 5- to 7-week-old plants to reduce downy mildew to a greater extent.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Shouan Zhang

Research topic(s) for pests/diseases/weeds:
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Peronospora belbahrii	Basil (Ocimum)	U.S.A. (SE)