Uptake and transport of phosphorus by Agrostis capillaris seedlings from rapidly hydrolysed organic sources extracted from P-32-labelled bacterial cultures
Uptake and transport of phosphorus by Agrostis capillaris seedlings from rapidly hydrolysed organic sources extracted from P-32-labelled bacterial cultures
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DOI：
10.1023/a:1004294617461
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发表时间：
1997-03-01
期刊：
影响因子：
4.9
通讯作者：
Ord, BG
中科院分区：
文献类型：
--
作者：
Macklon, AES;Grayston, SJ;Ord, BG
土壤细菌Serratia liquifaciens grimesii的培养物与P-32标记的磷酸盐一起生长，以产生均匀的P-32标记的微生物P源。细菌的提取物通过超声处理、透析和过滤制备，以提供澄清的无菌溶液，其特征在于溶解的有机和浓缩的P（DOP和DCP）和分子量范围。该提取物被用作毛细剪股颖的磷源。幼苗在营养液中，其中正磷酸盐省略。在一个时间进程的实验中，根表面磷酸酶活性增加，提取物添加到根培养基中，迅速水解DOP和正磷酸盐浓度迅速增加。这些过程在约8小时内完成，之后磷酸酶活性下降到其原始水平，并且植物从营养液中吸收非活性P，从而使其在48小时内达到其原始浓度。DCP浓度在整个实验中没有显著变化。这项工作清楚地表明，DOP，而不是DCP，作为一个相对简单的方法产生的细菌提取物的组成部分，被迅速水解和P可用于植物吸收。
Cultures of the soil bacterium Serratia liquifaciens grimesii were grown with P-32 labelled phosphate, to produce a uniformly P-32 labelled source of microbial P. Extracts of the bacteria were prepared by sonication, dialysis and filtration to provide st clear sterile solution which was characterised in terms of dissolved organic and condensed P (DOP and DCP) and molecular weight range. The extract was used as a source of P to Agrostis capillaris L. seedlings in nutrient solution from which orthophosphate was omitted. In a time course experiment, root surface phosphatase activity increased as soon as extract was added to the root medium, DOP was rapidly hydrolysed and orthophosphate concentration increased rapidly. These processes were complete within about 8 h, after which phosphatase activity fell to its original level, and the plants absorbed molybdate reactive P from the nutrient solution so that it reached its original concentration over 48 h. DCP concentrations did not change significantly throughout the experiment. This work clearly demonstrated that DOP but not DCP, as a component of a bacterial extract produced by a relatively straightforward method, was quickly hydrolysed and the P made available for plant uptake.