MONOCLONAL-ANTIBODIES AGAINST THE PLANT CYTOKININ, DIHYDROZEATIN RIBOSIDE

Three monoclonal antibodies (all IgG(1)) were prepared against the pla nt cytokinin dihydrozeatin riboside (diH[9R]Z) and characterized for s uitability in the isolation and quantification of dihydrozeatin-type p hytohormones. These antibodies detected as little as 5-10 pg of the ho mologous cytokinin when used in both competitive and noncompetitive im munoassays and each had characteristic crossreactivity with structural ly-related cytokinins. One antibody was used to quantify HPLC-purified diH[9R]Z recovered from wheat tissue. The same antibody also was link ed to an insoluble support for use in affinity purification of a mixtu re of cytokinins. These antibodies will be useful for purification and quantification of dihydrozeatin and its 9-riboside and 9-glucoside in plant tissue.