硼对棉花叶柄解剖结构的影响

缺硼的棉花叶柄上有墨绿色的环带形成,用扫描电镜观察发现环带部位的维管形成层、木质部、韧皮部及髓部组织的结构均发生异常变化,对叶柄的运输功能产生严重影响。

THE EFFECTS OF BORON ON THE ANATOMICAL STRUCTURES OF COTTON PETIOLES

The anatomical structure of boron-deficient cotton petioles changed in the following order when petiole rings appeared: firstly, vascular cambium abnormally thickened; secondly, pith cells deformed and abnormally thickened: thirdly, some vascular bundles cross-linked, their configuration disordered and cells deformed. Then. some particle mass could be found in pith cells. Later, the structure of the parenchyma cells in the xylem disappeared and phloem cells partly disintegrated. At the last stage of petiole rings, the number of sieves and vessels of boron-deficient petioles decreased, their shapes changed, while their diameters were reduced. It was also found that sieve piths were plugged by calluses and the proportion of scalariform ducts and pitted vessels declined.