Hilgardia
Hilgardia
Hilgardia
University of California
Hilgardia

Spotted wilt of the sweet pea

Authors

W. C. Snyder
H. Rex Thomas

Authors Affiliations

W. C. Snyder was Junior Plant Pathologist; H. Rex Thomas was Graduate Assistant in Plant Pathology.

Publication Information

Hilgardia 10(8):255-262. DOI:10.3733/hilg.v10n08p255. November 1936.

PDF of full article, Cite this article

Abstract

Abstract does not appear. First page follows.

Introduction

In the coastal counties of California the sweet pea, Lathyrus odoratus L., is frequently afflicted with a streak disease. The cause of the disease is sometimes obscured by viruses of the mosaic type or by resemblance to the description of bacterial streak of sweet pea.(5)4 It has, however, been proved to be a virus identical with that responsible for the spotted wilt disease of tomato. Recently(6) this virus has been reported as the cause of a streak disease of the garden pea, Pisum sativum L.

Symptoms

A characteristic symptom of the disease on sweet pea is a necrotic streaking of stems and petioles. The streaks are reddish brown to dull purple in color and in the advanced stage are conspicuous. They may run the entire length of the stem, parallel to the long axis, being found on analysis to consist of disconnected short streaks or a continuous long one. They have been seen to develop both above and below the point of virus inception.

Leaves and shoots may turn yellow and die. Early symptoms on the foliage appear as spots, usually 5 to 15 mm long, more or less circular or oval in shape, yellowish at first, with diffuse margins. Later the spots become somewhat brownish and form a pattern typical of the virus on other hosts. From these spots are developed yellowish sectors or zones, ordinarily one or only a few on each leaf. The spotting of the foliage is fairly definite in early stages, although not striking; but the general yellowing which may follow becomes a conspicuous symptom. Symptoms of the disease are shown in figure 1, A and D.

Blossoms on infected plants have been seen to develop a circular pattern in the pigment and the virus has been recovered from such material. Again, blighting of the whole shoot may occur prior to blossom formation.

Variability in the expression of symptoms has been observed. Plants infected early may yellow and die without showing other symptoms.

Literature Cited

[1] Gardner M. W., Tompkins C. M., Whipple O. C. Spotted wilt of truck crops and ornamental plants [Abstract.]. Phytopathology. 1935. 25:17

[2] Pierce W. H. The identification of certain viruses affecting leguminous plants. Jour. Agr. Research. 1936. 51:1017-39.

[3] Rawlins T. E., Tompkins C. M. The use of carborundum as an abrasive in plant-virus inoculations [Abstract.]. Phytopathology. 1934. 24:1147

[4] Stubbs M. W. Viroses of the garden pea, Pisum sativum L [Abstract.]. Phytopathology. 1936. 26:108-9.

[5] Taubenhaus J. J. The diseases of the sweet pea. Delaware Agr. Exp. Sta. Bul. 1914. 106:1-93.

[6] Whipple Otis C. Spotted wilt of garden pea. Phytopathology. 1936. 26:918-20.

[7] Zaumeyer W. J., Wade B. L. Mosaic diseases affecting different legumes in relation to beans and peas. Phytopathology. 1933. 23:562-64.

Snyder W, Thomas H. 1936. Spotted wilt of the sweet pea. Hilgardia 10(8):255-262. DOI:10.3733/hilg.v10n08p255

Also in this issue:

Lemon Industry in California: New economic and technological developments create market interactions between fresh fruit and lemon products

Citrus rejuvenation studies: Three basic soil treatments used in orchard investigations to determine best conditions for root growth and development

Drift of 2,4-D applied by plane: Better knowledge of wind direction and velocity as factors in drift contributes to reduction in number of damage suits

Isopropyl available for citrus: Registration of the isopropyl ester specifically for use as plant growth regulator on citrus permits this form of 2,4-D

Temperatures and frost damage: Measurements of temperature inversions and blossom counts show extent of frost damage in tests in deciduous orchards

Plant response to polluted air: Specific effects of air pollutants on plants vary according to plant species and modifying internal and external factors

Nutrition of date seedlings: Glasshouse tests with Deglet Noor variety in sand and soil cultures indicate which nutrients best stimulate growth

Boron deficiency of grapes: Soil application at one ounce of borax per vine supplies enough boron for normal growth after midwinter pruning

Caterpillar damage to tomatoes: Results based on one-year survey indicate no evidence of resistance to insecticides in nine commercial tomato fields

Symptomatic and etiologic relations of the canker and the blossom blast of Pyrus and the bacterial canker of Prunus

Inheritance of resistance to powdery mildew in beans

Webmaster Email: wsuckow@ucanr.edu