紫茎泽兰淋溶主效化感物质对旱稻幼苗根尖解剖结构的影响

采用营养液培养法和石蜡切片技术，研究了紫茎泽兰淋溶主效化感物质（泽兰二酮和羟基泽兰酮）对旱稻幼苗根尖解剖结构的影响。结果表明：两个化感物质分别处理后，旱稻幼苗的根呈现短小肿胀、侧根缺乏、且对营养液的吸收明显减少，这些症状随着化感物质浓度的增加而加剧。石蜡切片的结果表明，和对照相比，化感物质处理后的旱稻幼苗根尖的解剖结构发生了明显的变化，主要表现在顶端分生组织、静止中心和根冠的细胞排列混乱，细胞间隙加大，皮层薄壁组织细胞变得短而粗，以及表皮层细胞大量脱落等。讨论认为，旱稻幼苗根的形态结构变化，主要与紫茎泽兰化感物质对受体植物吲哚乙酸的干扰相关。

Influences of main-functional allelochemicals derived from the leachates of Ageratina adenophora Sprengel on anatomical structures of upland rice seedling root tips

With the methods of hydroponics and paraffin dissection,influences of main-functional allelochemicals(DTD and HHO)derived from the leachates of Ageratina adenophora Sprengel on anatomical structures of upland rice seedling root tips were investigated in this paper.Some obvious inhibition symptoms of roots had been found from the upland rice treated with DTD or HHO,such as becoming stunted and swollen,with poor lateral roots,and decreased absorption of Hoagland's solution,which enlarged with the increasing concentration of allelochemicals.Observations from the paraffin dissection showed that,the anatomical structures of treated upland rice root tip cells changed obviously,such as the arrangement confusion of cells from apical root meristem,quiescent center and root cap,increased middle lamella,the increased width and reduced elongation of cortex parenchyma cells,and the large numbers of slough off epidermis cells.It was concluded that,changes of anatomical structures from upland rice seedling root tips,were mainly related to the interference of DTD and HHO to indoly-3-acetic acid.