An improved bioassay for cytokinins using cucumber cotyledons.

The cucumber cotyledon greening bioassay is frequently used for detecting cytokinins. Beneficial modifications of the original technique included using 5-day-old cucumber (Cucumus sativus L., cv. National Pickling) cotyledons treated with combinations of 40 millimolar KCl and various concentrations of cytokinins. A dark incubation period of 20 hours was followed by an exposure to light for 3.5 hours. Under these conditions, extremely low (0.0001 milligram per liter) concentrations of N(6)-benzyladenine, zeatin, kinetin, or zeatin riboside can be detected. Of the four cytokinins tested, kinetin appeared to be the least active. With these improvements, the assay is 10 times more sensitive than is the previously described cucumber cotyledon greening bioassay for cytokinins.

[1]  R. Fletcher,et al.  Inhibition of photosynthetic pigments in cucumber cotyledons as a principle for a bioassay with fluridone , 1981 .

[2]  H. Tsuji,et al.  Effects of calcium on chlorophyll synthesis and stability in the early phase of greening in cucumber cotyledons. , 1980, Plant physiology.

[3]  D. C. Elliott Ionic Regulation for Cytokinin-dependent Betacyanin Synthesis in Amaranthus Seedlings. , 1979, Plant physiology.

[4]  R. M. Muir,et al.  The Effect of Potassium on Cotyledon Expansion Induced by Cytokinins , 1978 .

[5]  M. Dei Inter‐organ Control of Greening in Etiolated Cucumber Cotyledons , 1978 .

[6]  E. B. Dumbroff,et al.  Cytokinin and inhibitor activity in roots and stems of sugar maple seedlings through the dormant season , 1976 .

[7]  M. Weinberg,et al.  Effect of EPTC on Plastid Membrane Constituents in Germinating Cucumber Cotyledons , 1975, Weed Science.

[8]  R. Fletcher,et al.  Benzyladenine accelerates chloroplast differentiation and stimulates photosynthetic enzyme activity in cucumber cotyledons , 1974 .

[9]  R. Fletcher,et al.  Stimulation of chlorophyll synthesis in cucumber cotyledons by benzyladenine , 1973 .

[10]  D. Letham Chemistry and Physiology of Kinetin-Like Compounds , 1967 .

[11]  T. Sachs,et al.  THE ROLE OF CYTOKININS IN THE "FASCIATION" DISEASE CAUSED BY CORYNEBACTERIUM FASCIANS , 1966 .

[12]  C. Miller Evidence for the natural occurrence of zeatin and derivatives: compounds from maize which promote cell division. , 1965, Proceedings of the National Academy of Sciences of the United States of America.