黄花菜根系活力及营养物质的周年变化研究

黄花菜根系中的碳素营养贮藏物是蔗糖及少量还原糖，无淀粉的存在。氮素营养来源于秋季植株叶片氮化物的回流及纤细根的吸收。根系中的碳素和氮素营养，在春季转化成氨基酸，供新株萌发生长。根系中，纤细根活力最强，纺锤根最弱。纤细根是吸收器官、肉质根是贮藏器官，根状茎的贮藏功能较弱。早春幼芽萌发生长时，纺锤根中碳素营养消耗量最大，圆柱根次之。

DYNAMIC STUDIES ON THE ANNUAL CHANGES OF THE MAIN STORED NUTRIENTS AND THE ACTIVITIES OF THE ROOT SY8TEM OF DAY-LILY

Sucrose,together with a small amount of reducing sugar,was the basic form of carbonstorage in the roots of Day-lily.No starch accumulated in the root.The downwardtransportation from the leaves of the autumn plants and the absorption by the fibrous rootsof nitrogenous compounds made up the main storages of nitrogenous nutrients. Earlyspring-seedling mainly consumed the storages in the roots. The carbon nutrients in theroots seldom supplied the above ground part in the form of soluable sugar.Firstiy,theymust be changed into amino acid.The stored nitrogenous nutrients promoted the upwardtranslocation of carbon nutrients by means of amina acid. The fibrous roots were the most vigorous roots ,while the spindle roots were thevveakest The l4C radioactive intensity of the fibrous roots was stronger that of the fleshyroots,which indicated that the former had a strong competitve force,The fibrous rootswere the absorbing organ,while the fleshy roots were the main storage organ. The rhizom'sabilities to reserve were weak.The research also showed that the sprouting of the plantduring early spring mainly used the storage nutrients of the spindle roots,and the cylindricroots were a less important resourse.