TRANSMISSION AND HOST-RANGE STUDIES OF STRAWBERRY GREEN-PETAL VIRUS

The virus causing phyllody (virescence) in clover flowers was transferred by Cuscuta subinclusa to Fragaria vesca and Duchesnia indica plants which then produced symptoms of strawberry green-petal disease.
The jassid Euscelis plebejus (Fall.) in several forms, including E. lineolatus Brullé, transmitted green-petal virus from clover to clover, to and from a wide range of other hosts, and from but not to strawberry. Two viruses (or strains) were distinguished, one causing phyllody and the other witches' broom on clover; both were retained for more than 2 months by the vector, in which both had a latent period of about 30 days. Macrosteles viridigriseus (Edwards) also transmitted both viruses.
Variation in symptoms on strawberry plants infected naturally, and experimentally through dodder, suggested that two diseases have previously been grouped under the name 'green petal". It is proposed to distinguish these as ( a ) green petal caused by the virus inducing phyllody in clover, and ( b ) bronze leaf wilt caused by the clover witches' broom virus.