摘要
金冠和新红星苹果 (MaluspumilaMill.cvs.GoldenDelicious&Starkrimson)果实的成熟过程受脱落酸 (ABA)的调节。金冠果实从盛花后 90d起 ,ABA浓度从低到高依次为种子、果心、果肉 ,至盛花后 15 0d ,果心组织ABA浓度高于 1.8μmol/kgFW时 ,果实自发产生乙烯跃变。外源ABA处理能有效地触发发育晚期的金冠和新红星果实系统 2乙烯的合成 ,并使组织ACC合成酶 (ACS)与氧化酶 (ACO)活力与乙烯合成同步增加 ;fluridone (ABA生物合成抑制剂 )处理强烈抑制果实组织ABA的合成 ,抑制ACS、ACO活力 ,推迟系统 2乙烯的合成 ,显著抑制果实储藏后的完熟软化 ;二甲基亚砜 (DMSO)处理果实持续刺激果肉果心组织ABA浓度的增加 ,使果实成熟期显著提前。结论认为 。
Concentrations of endogenous abscisic acid (ABA) in apple ( Malus pumila Mill.)cvs. Golden Delicious and Starkrimson fruits increased during late period of fruit development in close correlation with fruit ripening. The ABA concentration peak in seeds of Golden Delicious fruits during the late period of fruit development occurred first, followed by those in core and flesh of fruits of both varieties (Fig.1). ABA was shown to initiate system 2 ethylene synthesis in the Golden Delicious fruits 150 days after full bloom when its concentration in fruit core exceeded 1.8 μmol/kg FW (Fig.6). Treatment of fruits of both varieties with exogenous ABA, before the climacteric period during the late developmental phases, triggered efficiently the synthesis of the system 2 ethylene and activated the ACC synthase and ACC oxidase in the fruits (Figs.5,7). Treatment of fruits with fluridone significantly decreased ABA concentrations in fruit tissues, delayed the system 2 ethylene production and inhibited fruit softening (Figs.2,3,5). Treatment of fruits with dimethylsulfonide induced significant increase in ABA concentration in flesh and core and hastened fruit ripening. We concluded that ABA plays an important role in regulating the ripening of apple fruits upstream of ethylene. The mechanism of ABA action on fruit ripening was discussed.
基金
国家自然科学基金资助项目!(39670518和39730340)
