Pathological anatomy of carrot root scab and some factors affecting its incidence and severity
AuthorsR. G. Grogan
F. W. Zink
K. A. Kimble
Authors AffiliationsR. G. Grogan was Professor of Plant Pathology and Plant Pathologist, Experiment Station, Davis; F. W. Zink was Specialist in the Experiment Station, Department of Vegetable Crops, E. Alisal Branch, Salinas; K. A. Kimble was Laboratory Technician IV, Department of Plant Pathology, Experiment Station, Davis.
Hilgardia 31(3):53-68. DOI:10.3733/hilg.v31n03p053. June 1961.
Abstract does not appear. First page follows.
Root scab of carrot has been a serious disease in California since at least 1937, when it was first observed in the state by (Ark and Gardner (1942; 1944))5 in the Santa Maria Valley. They described the disease and reported the cause to be direct root infection by Xanthomonas carotae (Kendrick) Bergey et al. originally described by Kendrick (1934), as the cause of a blight of the leaves and umbels of seed carrots. A similar disorder was reported by (Ramsey (1937)) and (Ramsey and Wiant (1941)) as occurring on California carrot roots shipped to the Chicago market. They isolated Fusarium spp. from the lesions, and concluded that the disease was caused by Fusarium.
From experimentation and observations the present paper evaluates the effect of several factors on the prevalence and severity of the disease and describes its pathological anatomy.
Distribution in California
Carrot root scab in California occurs commonly in the Salinas Valley, from Chualar south to King City, and in the Lompoc and Santa Maria valleys. In 1955 it also occurred in a late fall crop near Patterson, but did not recur there the following year. The disease has not been observed in the carrot-growing areas of the lower Salinas Valley, near the Pacific Ocean, although as many as 18 carrot crops in twenty years have been grown in some fields there.
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Ramsey G. B., Wiant J. S. Market diseases of fruits and vegetables. Asparagus, onions, beans, peas, carrots, celery and related vegetables. U. S. Dept. Agr. Misc. Pub. 1941. 440:70 DOI: 10.5962/bhl.title.65757 [CrossRef]
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Rose virus and virus-like diseases
Using embryo transfers to increase twinning
Mechanical harvester for fresh-market plums
Use-value assessment and land conservation
Growth regulators affect apple maturity
Yellow berry of wheat linked to protein content
Meadowfoam: Potential new oil crop
Egg traps monitor navel orangeworm
Electronic color sorting of cantaloupes for ripeness
Gypsy moth: Possible threat to California trees