伊贝母种子萌发和籽苗建立

THE SEED GERMINATION AND THE SEEDLING FORMATION OF FRITILLARIA PALLIDIFLORA SCHRENK

在子叶出土萌发的植物类型中,伊贝母种子萌发过程是罕见的。萌发初期,子叶优先生长。首先伸长而突破种皮,接着长出地面,此后,胚根才开始生长并产生不定根。种子萌发后形成特殊籽苗。在地上部分,子叶变绿,成为第一生长季唯一的同化叶;在地下部分,上胚轴扁平化,芽鳞肉质化,于是形成小鳞茎。籽苗形态属于最简化的类型。伊贝母的籽苗与其营养更新苗相比,是很弱小的。

In the germinative plant type, in which cotyledon is epigeal, the course of germination of Fritillaria Pallidiflora seed is comparatively seldom to meet. During earlier period the course a cotyledon specialized haustorium on the apex has a priority of growth. At first it lengthens up to burst the testa, and then grows out of the stretches,subsequently, radicle begins to grow and produces the seminal adventitious roots.Arther germination the seed borms a special seedling. On the ground section of the seedling, the cotyledon gradually getting green becomes the only assirnlation leaf during the first growth season under the ground epicotyl and bud scale respectively become flat and succulent, then form small bulb. The structure of the seedling be longs to the simplest type. Compared with the young plant nourished by vegetative organ, the seedling looks very weak and poor.