6种野生耐旱花卉解剖学特征与耐旱性的关系

为给干旱、半干旱地区野生花卉的引种驯化提供理论依据,对燕山地区6种野生耐旱花卉营养器官的结构进行了观察与测定,对其中的叶片角质层厚度、叶片气孔密度、栅栏组织厚度与海绵组织厚度的比值、第1层栅栏组织细胞密集度、侧脉间距离、根皮层厚度与根半径之比、初生木质部导管数目、后生木质部导管平均直径等8个主要耐旱结构指标作了方差分析与多重比较,并采用隶属函数对种间耐旱性进行了综合评判。结果表明:6种野生耐旱花卉叶片耐旱性强弱依序为南蛇藤>栓翅卫矛>叶底珠>孩儿拳头>木半夏>蚂蚱腿子;初生根耐旱性强弱依序为叶底珠>孩儿拳头>栓翅卫矛>南蛇藤>蚂蚱腿子>木半夏,与其实际耐旱能力的排序(叶底珠>栓翅卫矛>木半夏>孩儿拳头>南蛇藤>蚂蚱腿子)相比,出现了顺序上的交错现象;所选耐旱指标在对花卉耐旱的作用上,以角质层厚度、栅栏组织厚度与海绵组织厚度的比值和第1层栅栏组织细胞密集的贡献最大,初生根的贡献较小,这预示了6种野生耐旱花卉解剖结构与耐旱途径的多样性。

Relationship between Anatomical Structures and Drought Resistance of Six Wild Flowers

In order to provide a theoretical basis for introduction of wild flowers in arid and semi-arid region,anatomical structures of vegetative organs in six wild flowers were studied.The indexes were thickness of cuticle in leave,stoma density,thickness ratio of palisade tissue to spongy tissue,density of cell in the first palisade tissue,lateral vein distance,ratio of cortex thickness to radius of root,number of vessels in primary xylem,diameter of vessel in secondary xylem.The eight indexes were researched by analysis of variance and multiple comparisons,and drought resistances between species were analyzed by membership function.The results showed that the drought resistance sequence from strong to weak was Celastrus orbiculatus Thunb.,Euonymu phellomanus Loes.,Securinega suffruticosa(Pall.) Rehd.,Grewia biloba var.parviflora(Bge.) Hand.,Elaeagnuas multiflora Thunb.,Myripnois dioica Bge..The drought resistant sequence of primary roots from strong to weak was S.suffruticosa(Pall.) Rehd.,G.biloba var.parviflora(Bge.) Hand.,E.phellomanus Loes.,C.orbiculatus Thunb.,M.dioica Bge.,E.multiflora Thunb..While the real drought resistance was S.suffruticosa(Pall.) Rehd.,E.phellomanus Loes.,E.multiflora Thunb.,G.biloba var.parviflora(Bge.),C.orbiculatus Thunb.,M.dioica Bge.. Among the indexes,cuticle thickness,thickness ratio of palisade tissue to spongy tissue,and density of cell in the first palisade tissue played important role in drought resistance.That suggested that the six plants had different drought resistance strategies.