沙芥植株营养器官不同时期解剖结构特征与抗旱性关系研究

采用石蜡切片法,对1年生沙芥幼苗期、旺盛生长期、生长衰退期的根、茎、叶等材料进行了形态及解剖学研究.结果表明:幼苗期已分化出发达的保护组织、输导组织和贮水组织；旺盛生长期各器官输导组织发达,但机械组织不发达.在旺盛生长期和生长衰退期,根、茎均具有发达的髓,髓内有异常次生生长形成的维管组织,用于贮藏水分和养分.为适应沙漠干旱环境,沙芥各器官还形成了表皮、副表皮、泡状细胞、下陷的气孔和较大的气孔下室、长短导管分子并存及环栅型叶等特化结构.

Study on appearance and anatomy of Pugionium cornutum (L.) Gaertn in different period

The morphological structure of roots, stems and leaves of annual Pugionium cornutum (L.) Gaertn in seedling stage, vigorous growth and growth recession were observed with paraffin method. The results showed that well-developed protective tissue transfusion tissue and aqueous tissues have differentiated in seeding stage. The well-developed transfusion tissue could be found in all organics, but mechanical tissue developed badly in vigorous growth. The roots and stems have well -developed medulla with the fibrovascular tissue, which was the product of abnormal secondary growth and used for storing water and nutrition, in vigorous growth and growth recession. Specialized structures such as epidermis, accessory epidermis, bulliform cell, deep stoma, large substomatic chamber, vessel element and ring-palisade could be found in Pugionium cornutum (L.) Gaertn which adjust to the drought environment in desert.