单性结实和自花结实柑橘果实发育过程中IAA、ZR和GA3含量的变化

对单性结实的龟井温州蜜柑(以下简称龟井)和自花结实的鄂柑1号橘(以下简称鄂柑1号)果实发育过程中不同部位的IAA、ZR和GA₃的含量变化进行了测定。结果表明:(1)两品种果皮IAA含量呈相似的变化趋势,均于果实增大期间出现明显高峰,但鄂柑1号的IAA高峰值显著较高;二者果皮ZR含量动态却相反,增大期间龟井果皮ZR的含量相对较高且趋上升,而鄂柑1号却趋下降;二者果皮GA₃含量均于增大期间出现类似的上升过程,之后均趋下降。(2)龟井果肉IAA、ZR和GA₃含量前期均较高,此后均明显下降并居较低水平;而鄂柑1号果肉IAA和GA₃均于增大期间出现明显的上升且含量明显高于龟井,而ZR含量与龟井一样呈下降趋势,但ZR的含量更低。(3)鄂柑1号种子的IAA、ZR和GA₃在花后72d均相对较高,之后急剧回落至相对较低的稳定水平。

Changes in Concentrations of IAA,ZR and GA3 during Fruit Development of Parthenocarpic and Self-pollinated Citrus Cultivars

Changes in concentrations of indol-3-acetic acid(IAA),ribosylzeatin(ZR) and gibberellin(GA₃) in different fruit positions of Kamei satsuma mandarin (Citrus unshiu Marc.) and Egan 1 tangerine (C. reticulatau Blanco) fruits were investigated during fruit development. The results indicated that IAA concentrations in the rinds of the two cultivars showed similar trends with obvious peaks at the stage of fruit enlargement, though Egan 1 had the higher value. Opposite change patterns were observed in ZR concentrations between the two cultivars during fruit enlargement, when ZR concentration in Kamei rind was relatively high and increased progressively, whereas that of Egan 1 was declined. GA₃ concentrations of both cultivars presented similar change trend, increasing during fruit enlargement and then decreasing. IAA, ZR and GA₃ concentrations in Kamei pulp, were relatively high at early stage of fruit development. Thereafter, they were reduced conspicuously and remained at low levels. In Egan 1, IAA and GA₃ concentrations were clearly increased during fruit enlargement, which were significantly higher than those of Kamei. ZR concentration in the pulp of Egan 1 decreased, with a trend similar to Kamei, but the former was lower than the latter. IAA,ZR and GA₃ concentrations in the seed of Egan 1 were relatively high at 72 days after full bloom,followed by abrupt decrease to low but constant levels.