ABT5号增产灵对甜菜根结构形成的影响

田间试验表明，施用ＡＢＴ５号增产灵明显提高甜菜肥大直根的产量，且浸种处理的增产效果明显高于叶喷，而对含糖率无影响；形态指标测定表明，ＡＢＴ５号增产灵促进甜菜生长发育，加快了出叶速度，每株总叶片数增多，主根脱皮提前，体积增大；解剖观察表明，ＡＢＴ５号增产灵不影响甜菜根的初生生长和次生生长，只使三生生长提前，三生维管束轮数增加．甜菜苗期叶片数目与根结构的形成存在密切的相关性，且不受ＡＢＴ５号增产灵的影响。因此，甜菜苗期叶片数目仍可作为判断根结构的依据。

EFEECT OF APPL ING ABTS GROWTH PROMOTER ON THE STRUCTURAL FORMATION OF ROOTSIN SUGARBEET(Beta vulgaris L.)

The results indicated that ABT5 growth promotor obviously increased the yield of roots and this effect was more obvious when the drug was used to soak the seeds rather than when it was used to sprinkle the leaves of the plant. The applieation of this promoter had no effect on the sugar percentage of the root.The number of leaves and the volume of the root were increased and the time for shedding of the epidermis and cortex was advanced by the application of the promoter. The primary and secondary growths of the root were not changed. but the time for the onset of the tertiary growth was moved up and the ring number of the tertiary vascular bundles was increased when ABT5 growth promoter was used.The number of leaves was closely correlated with the structural formation of root during seedling period and this correlation was not influenced by the promoter application. It is,therefore,suggested that the number of leaves at the seedling stage can be used as a basis for judgement of the structure if roots.