黑穗醋栗(Ribes nigrum L.)茎的解剖结构与不定根形成的研究

本实验结果表明,黑穗醋栗“厚皮”和“薄皮”品种之间茎的结构无明显区别,幼茎均由表皮、皮层、维管柱、髓和髓射线组成。仅“厚皮”茎的角质膜较厚;皮层和髓细胞较小,排列紧密;“薄皮”品种茎的角质膜较薄;皮层和髓部的细胞较大,排列疏松,髓部体积亦较“厚皮”的大,“薄皮”的茎较柔软容易下垂。两品种幼茎的表面均有腺体分布,分泌挥发性物质。未经扦插的一年生成熟茎内有“先成不定根原基”。经过水培(或扦插)的成熟茎内有“诱发不定根原基”。不定根原基常起源于髓射线(或多列射线)与形成层带交接的部位;其位置可能正对皮孔内方或在其一侧,也可在无皮孔区的周皮内侧。不定根可从皮孔内伸出,亦可从皮孔一例或其附近的周皮缝隙中伸出。常簇生在插条的茎节附近或沿插条节间排列成2～3纵列。

STUDIES ON ANATOMICAL STRUCTURE OF THES TEM AND FORMATION OF THE ADVENTITIOUS ROOT OF BLACKCURRANT (Ribes nigrum L.)

The anatomical structure of the stem of var. 'Thick--skin' is similar to that or var.'Thin--skin' or black currant. Its primary body consists of epidermis, cortex, vascular cyl-inder, ray and pith, but the cuticle layer of var. 'Thick--skin' is thicker and the cell size ofits cortex and pith is smaller. Glandular scalcs may be found on the surface of the young stem in both varieties. On the cross-- section of l-- year-- old mature stem the phellogen is initiated fromparenchyma of primary phlocm. The structure of lenticle is of simple type. The filling tissue iscomposed of suberized cells which may show annual growth layer. The performed adventitious root primordia may be observed in the 1--year--old maturestem without cutting. And the induced adventitious root primordia may be observed in themature stem with watering cutting. The adventitious root primordia are initiated in the raynear the cambium. They emerge from lenticels, the side of lenticels or the rupture of nearperiderm. Adventitious roots usually aggregate in clusters near nodes or are arranged in 2～3rows longitudinally.