Production and Action of Ethylene in Senescing Leaf Discs: Effect of Indoleacetic Acid, Kinetin, Silver Ion, and Carbon Dioxide 1
AUTOR(ES)
Aharoni, Nehemia
RESUMO
Supraoptimal concentrations of indoleacetic acid (IAA) stimulated ethylene production, which in turn appeared to oppose the senescence-retarding effect of IAA in tobacco leaf discs. Kinetin acted synergistically with IAA in stimulating ethylene production, but it inhibited senescence. Silver ion and CO2, which are believed to block ethylene binding to its receptor sites, delayed senescence in terms of chlorophyll loss and stimulated ethylene production. Both effects of Ag+ were considerably greater than those of CO2. IAA, kinetin, CO2, and Ag+, combined, acted to increase ethylene production further. Although this combination increased ethylene production about 160-fold over that of the control, it inhibited senescence. Treatment with 25 μl/l of ethylene in the presence of IAA enhanced chlorophyll loss in leaf discs and inhibited by about 90% the conversion of l-[3,4-14C] methionine to 14C2H4 suggesting autoinhibition of ethylene production.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=543367Documentos Relacionados
- Effect of Silver Ion, Carbon Dioxide, and Oxygen on Ethylene Action and Metabolism 1
- Effect of Gibberellic Acid, Kinetin, and Ethylene plus Carbon Dioxide on the Thermodormancy of Lettuce Seed (Lactuca sativa L. cv. Mesa 659) 12
- Stimulation of Ethylene Production in the Mung Bean Hypocotyls by Cupric Ion, Calcium Ion, and Kinetin 1
- Carbon Dioxide Enhances the Development of the Ethylene Forming Enzyme in Tobacco Leaf Discs 1
- Reversal of Induced Dormancy in Lettuce by Ethylene, Kinetin, and Gibberellic Acid