Cytokinin activity from the phloem sap of Xanthium strumarium L.
Excretory products from aphids feeding on flowering and vegetative Xanthium plants contained a cytokinin active in the soybean-callus assay. No cytokinin activity was found in honeydew collected from aphids feeding on a chemically defined diet. Soybean-callus assays indicated that honeydew from aphids feeding on flowering plants contained more cytokinin than honeydew from vegetative plants.
Biological Laboratories, Harvard University, Cambridge, Massachusetts, USA.
D A
DA
Phillips
C F
CF
Cleland