A role for ethylene in the yellowing of broccoli after harvest
A role for ethylene in the yellowing of broccoli after harvest
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DOI：
10.21273/jashs.119.2.276
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发表时间：
1994-03
影响因子：
1.9
通讯作者：
M. Tian;C. Downs;R. Lill;G. King
中科院分区：
文献类型：
--
作者：
M. Tian;C. Downs;R. Lill;G. King
Ethylene production from florets of 'Shogun' harvested broccoli ( Brassica oleracea L.var. italica) held at 20C in darkness increased as the sepal tissues yellowed. The pattern of respiration rate and ethylene production from branchlets or entire heads was similar, although the magnitude of ethylene and carbon dioxide production appeared to be diluted by the other fleshy stem tissues. The reproductive structures, stamens and pistil, may have a role in determining the rate of sepal degreening, since removing them from florets reduced the yellowing rate. The pistil and stamens also had 7-fold higher levels of 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase activity and more than double the ethylene production of other tissues within the floret. Stamen ACC oxidase activity was high on the first day after harvest, before yellowing became obvious. Changes in ACC oxidase activity of the pistil and stamens mirrored changes in ACC content in these tissues. The climacteric status of harvested broccoli was confirmed by exposure to 0.5% propylene. Propylene stimulated respiration and ethylene production and accelerated yellowing (measured as chlorophyll and hue-angle decline). Broccoli tissues did not respond to propylene immediately after harvest. In tissues aged in air before treatment, the time for response to propylene was shorter, a result suggesting a change in tissue sensitivity. Ethylene exposure induced a dose-dependent decline in hue angle, with 1 ppm ethylene giving the maximum response.
