Ethylene Characteristics and Effects
socrtwo
characteristics and effects. I cross posting the lists as they exist
now:
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Some Plant Ethylene Characterics
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* Rapidly diffuses because it's a gas
* Synthesized in nodes of stems
* Synthesized during germination
* Synthesis is stimulated by auxin and maybe cytokinin as well
* Ethylene levels are decreased by light
* The flooding of roots stimulates the production of ACC which travels
through the xylem to the stem and leaves where it is converted to the
gas
* In pollination, when the pollen reaches the stigma, the precursor of
the ethylene, ACC, is secreted to the petal, the ACC releases ethylene
with ACC oxidase.
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List of Plant Responses to Ethylene
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* Stimulates leaf and flower senescence
* Stimulates senescence of mature xylem cells in preparation for plant
use
* Inhibits shoot growth except in some habitually flooded plants like
rice
* Induces leaf abscission
* Induces seed germination
* Induces root hair growth - increasing the efficiency of water and
mineral absorption
* Induces the growth of adventitious roots during flooding
* Stimulates epinasty - leaf petiole grows out, leaf hangs down and
curls into itself
* Stimulates fruit ripening
* Induces a climacteric rise in respiration in some fruit which causes
a release of additional ethylene. This can be the one bad apple in a
barrel spoiling the rest phenomenon.
* Affects neighboring individuals
* Disease/wounding resistance
* Triple response when applied to seedlings - stem elongation slows,
the stem thickens, and curvature causes the stem to start growing
horizontally. This strategy is thought to allow a seedling grow around
an obstacle
* Inhibits stem growth outside of seedling stage
* Stimulates stem and cell broadening and lateral branch growth also
outside of seedling stage
* Interference with auxin transport (with high auxin concentrations)
* Inhibits stomatal closing except in some water plants or habitually
flooded ones such as some rice varieties, where the opposite occurs
(conserving CO2 and O2)
* Where ethylene induces stomatal closing, it also induces stem
elongation
* Induces flowering in pineapples