甜菜根际磷酸酶分泌特性的研究

The properties of phosphatase excretion in rhizosphere of sugar beet

甜菜根际磷酸酶的分泌特性是其根际土壤中有机磷有效性的决定性因子。采用液体培养和改进的Kuchenbuch微型盆土培法,对甜菜根际磷酸酶的分泌情况进行了较详细的研究。结果表明:⑴甜菜对有机磷的吸收是以有机磷的分解转化为前提,不同基因型的甜菜根际产生磷酸酶的种类、分布范围及分泌总量存在明显差异,并表现在对有机磷胁迫的抗耐能力方面的差别,某些基因型对有机磷表现出极强的分解、吸收和适应能力;⑵甜菜根系可分泌出多种磷酸酶,其中绝大多数品种以酸性磷酸酶为主,其次是中性磷酸酶,而碱性磷酸酶几乎没有;⑶甜菜各品种(系)根际磷酸酶的分布均表现出从根表向根际以外逐渐由高到低的特点,当达到一定点趋于一个恒定的值,符合方程y=yo+ae(-bx)的分布规律。

The excreting properties of phosphatase in rhizosphere of sugar beet is its decisive factor of organic phosphorus effect in the rhizosphere soil.Liquid culture and improved soil culture with miniature pot of Kuchenbuch were adopted,the excreting situation of the phosphatase in rhizosphere of sugar beet was investigated in detail.The results showed that:⑴it was the premise condition that organic phosphorus was not absorbed by sugar beet until was decomposed and conversed,there were significant difference in the kinds,distribution range and total amount of phosphatase excreted in the rhizophere of different shgar beet gen otype,and there was also difference in the stress resistance,some gen otypes showed very strong decomposition,absorption and adaptation ability to organic phosphorus;⑵several kind s of phosphatase could be excreted by roots of sugar beet,among which the acid phosphatase was the main,secondly the neutral phosphatase,however the alkaline phosphatase was little;⑶the distribution of phosphatase in rhizophere of each sugar beet variety(line)showed the same trend as decreased gradually from the root surface to a distant place,it matched the distribution regulation of equation y=y o +ae (-bx).