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利用常规石蜡切片法对灰叶胡杨(Populus pruinosa)根蘖繁殖特性进行形态解剖学研究。结果表明:灰叶胡杨横走侧根由周皮、次生维管组织和四原型的初生木质部构成,具有次生维管组织中维管射线、次生韧皮薄壁组织发达的结构特征。灰叶胡杨的根蘖繁殖源于横走侧根上不定芽的发生及生长发育。不定芽起源于横走侧根的木栓形成层,木栓形成层经细胞分裂活动形成不定芽原基,不定芽原基细胞分裂和生长分化形成在横走侧根表面可观察到的不定芽,进而生长发育为根蘖苗。不定芽的发生具有同步或非同步的时间特征和单点或多点聚集的空间分布特点,在生长发育过程中其基部可以产生新的不定芽。不定芽发生、分布和生长特点是根蘖苗大小不一、密集丛生的内在原因,表明灰叶胡杨具有较强的根蘖繁殖能力。
Morphology and anatomy of root growth of Populus pruinosa were studied by conventional paraffin section method. The results showed that the lateral root of Populus euphratica was composed of periderm, secondary vascular tissue and primary xylem of quadruplex, which had the features of vascular tube and secondary phloem parenchyma in secondary vascular tissue. The root tillering of Populus euphratica stems from the emergence and growth of adventitious buds on lateral roots. The adventitious buds originated from cork cambium, which transversal lateral roots. Cork cambium formed adventitious bud primordia by cell division activity, adventitious bud primordia cells divide and grow and differentiate to form adventitious buds which can be observed on the lateral root surface. Growth and development as the root tillering seedlings. Adventitious buds have synchronous or nonsynchronized temporal characteristics and spatial distribution characteristics of single or multi-point aggregation, and new adventitious buds can be formed at the base of the adventitious buds during growth and development. The occurrence, distribution and growth characteristics of adventitious buds are the internal causes of different sizes and dense clusters of tiller seedlings, indicating that Populus euphratica has strong root tillering ability.