Dual function of auxin during leaf abscission in poplar
نویسندگان
چکیده
Background Leaf abscission is an important trait for biomass production and seasonal acclimation in deciduous trees of the temperate region. Various plant hormones are involved in the timing of abscission. For example, ethylene signaling is required to induce hydrolysis of cell walls, while an auxin gradient [1] was suggested to act upstream of ethylene on the onset of leaf abscission. Besides pharmacological application of auxins on cut surfaces of explants, experimental evidence for such a gradient is however lacking. In addition to its function in temporal control, auxin has also been suggested to be a positional signal specifying the cells of the abscission zone [2].
منابع مشابه
Auxin is a long-range signal that acts independently of ethylene signaling on leaf abscission in Populus
Timing of leaf abscission is an important trait for biomass production and seasonal acclimation in deciduous trees. The signaling leading to organ separation, from the external cue (decreasing photoperiod) to ethylene-regulated hydrolysis of the middle lamellae in the abscission zone, is only poorly understood. Data from annual species indicate that the formation of an auxin gradient spanning t...
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