AuthorsHenry H. P. Severin
R. C. Dickson
Authors AffiliationsHenry H. P. Severin was Associate Entomologist in the Experiment Station; R. C. Dickson was Associate in the Experiment Station.
Hilgardia 14(8):465-490. DOI:10.3733/hilg.v14n08p465. June 1942.
Abstract does not appear. First page follows.
Among the virus diseases encountered in the course of the investigation of celery calico on perennial delphiniums (5)4 was one which caused ringspot of perennial delphinium; this was found on unknown varieties or hybrids at Berkeley, Hillsborough, and Montara, California, the symptoms being identical in the three places. The symptoms of celery calico on delphinium are confined to the basal or intermediate leaves, whereas ringspots occur on all of the leaves.
Work was undertaken on the host range, properties of the virus, and determination of the vectors. The symptoms of the disease were compared with those of ringspot previously reported on delphiniums.
Valleau (7) found a virosis of delphinium in Kentucky closely resembling ringspot of tobacco. He later (8) reported a delphinium virus causing a “coarse etch” when transferred to tobacco and suggested seed transmission. In another paper (9), he described the symptoms in more detail and gave delphinium, tobacco, tomato, and cucumber as host plants of the virus. The symptoms on delphinium consist of chlorotic ring patterns on individual lobes of the affected leaf, sometimes extending into every lobe. He also stated that this disease occurred naturally in tobacco both in Kentucky and in Minnesota and that “this virus corresponds most closely to the typical cucumber viruses.”
Johnson (3) found patterns on delphinium similar to the large, yellowish, concentric patterns on dark tobacco caused by a tobacco-ringspot virus identical with that described by Fromme, Wingard, and Priode (2).
Burnett (1) described a virus disease causing dark-brown to black lesions on delphinium leaves. Tobacco plants inoculated from these showed an irregular mottle with ring-and-line patterns. Delphinium plants inoculated from these tobacco plants developed dark-brown ring and- line patterns during the first season.
 Burnett G. Stunt, a virosis of delphinium. Phytopathology. 1933. 24:467-81.
 Fromme F. D., Wingard S. A., Priode C. N. Ringspot of tobacco, an infectious disease of unknown cause. Phytopathology. 1927. 17:321-28.
 Johnson E. M. Virus diseases of tobacco. Kentucky Agr. Exp. Sta. Bul. 1930. 306:81-88.
 Rawlins T. E., Tompkins C. M. Studies on the effects of carborundum as an abrasive in plant virus inoculations. Phytopathology. 1936. 26:578-87.
 Severin H. H. P. Celery calico on perennial delphiniums and certain other host plants. Hilgardia. 1942. 14(11):411-40. DOI: 10.3733/hilg.v14n08p441 [CrossRef]
 Severin H. H. P. The susceptibility of perennial delphiniums to six viruses. Hilgardia 1942. (in press). DOI: 10.3733/hilg.v14n10p549 [CrossRef]
 Valleau W. D. [A Delphinium virosis in Kentucky. Plant Disease Reporter Sup. 1927. 65:419 (Mimeo.) [Issued by U. S. Bur. Plant Indus.]
 Valleau W. D. [Delphinium virus causing “coarse etch” in tobacco.]. Plant Disease Reporter. 1930. 14:118 (Mimeo.) [Issued by U. S. Bur. Plant Indus.]
 Valleau W. D. A virus disease of delphinium and tobacco. Kentucky Agr. Exp. Sta. Bul. 1932. 327:81-88.
Also in this issue:Irrigation pumping plant characteristics in the San Joaquin Valley
Gibberellins on grape
Suffolk and Southdown rams as sires of market lambs compared in long-term study
Management of weeder geese in commercial fields
Growth responses of three annual clovers to treatments with 2,4-D—Part II
Collapse in California woods
Mallet wound canker of almond trees
Wind machine-orchard heater system for frost protection in deciduous orchards
Breeding potatoes for disease resistance
Potash on potatoes for chips
Potash: In California vineyards
Chemical weed control in azalea seed crop
Copper in embryonic development
Color and stability of wines
Control of the vinegar fly
Embedding media for electron microscopy
Effect of environment on rice plants
Moderate grazing protects future forage production
Corrosion of aluminum irrigation pipe
Chemical regulator of plant growth
Lygus bug tolerance: To insecticides
Land disposal of industrial waste waters
Infection of perennial delphiniums by California-aster-yellows virus
Celery calico on perennial delphiniums and certain other host plants