摘要
用光学显微镜和电子显微镜技术研究了热带落叶季雨林树种白格（Albiziaprocera）旱季休眠的特点。白格对旱季适应的主要策略是脱掉易于损失水分的大型复叶和小枝，留下具有明显抗旱结构特征的大分枝和树干。大枝和树干具有很厚的树皮，其中含有大量充满水分的薄壁组织细胞和发育良好的木栓层。由一纵列发育程度不同的芽组成的休眠腋芽，被叶柄基部和茎的突起紧紧包裹。与温带落叶树木不同，白格和其它研究过的热带落叶树木休眠期韧皮部细胞结构与生长期比较改变较小，麦明热带树木在休眠期虽然暂时停止生长，但却处于能够随时恢复活跃的代谢和生长状态。笔者认为这是对热带环境条件的适应。
An attempt was made by using both light and clectron microscopy on the dormancy, in dry season, of Albizia procera (Roxb), Benth, a tree in tropical deciduous seasonal rain forest on Hainan Island. To adapt to the dry season,A. Albizia sheds not only large compound leaves but also branchlets and keeps larger branches and trunk which are both characterized by resistance to drought. All the smaller branchlets have a weakening abscission zone and tends to be shed if necessary. The large branches and trunk have considerable thick bark which contains numerous parcnchyma cclls full of water and well developed phelloderm. A series of axillary buds longitudinally arranged in a leaf axil are closely covered by leaf base and stem protrusions. Unlike deciduous trees in the north temperate zone, A. procera and othcr tropical deciduous trees under observation have the funetional phloem with about the same thickfless at dormancy stage as at growth stage,and keeps large vacuoles and smooth plasma membrane on the parenchyma cells of the pholem at both dormancy and growth stages,suggesting that the trees are rcady at all times to resume active metabolism and growth although they cease growing temporarily at dormancy stage. This is believed to be an adaptation of the trees to the tropical environmental conditions.
出处
《热带作物学报》
CSCD
1997年第2期98-107,共10页
Chinese Journal of Tropical Crops
基金
国家自然科学基金!39460005
关键词
休眠
抗旱
热带树木
白格
解剖
旱季
Dormancy
drought resistance
tropical trees
Albizia procera
