机构地区: 华南农业大学园艺系
出 处: 《园艺学报》 1998年第4期319-323,共5页
摘 要: 以人工气候室模拟台风中大气水蒸气压亏(VPD)骤降,发现朱砂桔叶水势上升幅度大于果水势,叶果间水势差增大,致使水分向果分配,但效应短暂,而复水增加土壤水分对果膨大生长的影响更为明显和持久。控水期间果内渗透调节启动,同时叶从果中抽取更多水分也使果水势下降,复水后胁迫果的水势明显低于叶水势,使膨大生长更明显。“台风”引发的膨大生长包含被动和主动两种吸水机理,而以前者为主。模拟台风与自然台风不同,未能引起乙烯发生量加大,但引起酸性转化酶和三磷酸腺苷酶(ATPase)活性上升,有助于同化产物积累和渗透吸水及需能代谢增强。 Drastic drop of atmospheric vapour deficits was simulated in a phytotron to observe the“typhoon”effect on the fruits of potted mandarin trees subject to different watering treatments.The results showed that“typhoon”caused an“expansion jump”of fruits,especially in the water stressed/re watered(WS/RW)treatment.This effect was found transient under the constant water stressed(CWS)treatment.Difference between leaf and fruit water potentials was enlarged by the“typhoon”in favour of water influx into the fruits through raising the water potential in the leaf rather than in the fruit.Soil water supply increased by re watering(RW)was found to contribute more(over 60%)to the expansion growth than was the drop of atmospheric VPD.The involvement of ethylene in fruit expansion growth as seen under the natural typhoon climate was not verified during“typhoon”in the phytotron.The mechanisms of water uptake by fruit involved both passive and active in nature,the former being overriding.Activities of acid invertase and ATPase were found increased during“typhoon”.