作　　者： ; ; ; ; ;

机构地区： 广西大学农学院

出　　处： 《西北植物学报》 2008年第4期724-729,共6页

摘　　要： 以2个黑麦品种‘冬牧70’和‘King’为材料，研究了植物对难溶性磷酸盐的吸收及活化，以揭示植物抵御酸性土壤逆境的机制。结果显示，（1）在活性铝含量高的赤红壤中施用磷酸铝、磷酸铁、磷酸钙等难溶性磷酸盐后，植株的生物产量和磷的积累量分别增加了0．84～6．38倍和0．60～20．5倍，且施用难溶性磷酸盐后‘冬牧70’的生物产量和磷的积累量的增加量明显高于‘King’。（2）铝胁迫下2种黑麦根系分泌物中的阴离子组分均能溶解难溶性磷酸盐，而在中性或阳离子组分中的难溶性磷酸盐溶解不显著；HPLC图谱显示，阴离子组分中含有柠檬酸和苹果酸。（3）铝胁迫下根系有机酸分泌量随铝处理浓度（10、30、50μmol／L AlCl3）的增加而增加，而且在柠檬酸或苹果酸溶液中难溶性磷酸盐的溶解度显著增加，其溶解的磷随有机酸浓度的增加而增加。（4）黑麦‘冬牧70’品种对难溶性磷酸盐的吸收、阴离子组分对难溶性磷酸盐的溶解及有机酸分泌作用均较‘King’强。结果表明，在铝胁迫下根系分泌的有机酸是黑麦活化、吸收土壤中难溶性磷的有效机制。 To elucidate the mechanisms of plants adapting to the stresses in acid soils,two cultivars of rye （Secale cereale L. ）, ‘King＇ and ‘Wintergrazer-70 （Win）＇,were objected to investigate the utilization of sparingly soluble phosphates by plants. It was shown that plant biomass and the accumulation of phosphorus in upper parts of ryes increased by 0.84 to 6.38 fold and 0.6 to 20.5 fold,correspondingly,after the application of sparingly soluble phosphates （aluminum phosphate, ferric phosphate, calcium phosphate） to lateritic red soil. Further more,the increase in biomass and accumulation of phosphorus in ‘Win＇ was more significantly. The dissolving of sparingly soluble phosphate to the solution with anion components of exudates from roots treated with Al elevated,and the level of dissolved phosphate in solution with neutral or cation components failed to increase. Both citrate and malate could be detected by HPLC in anion components of the exudates, and the amount of organic acids increased with increasing Al concentration（10,30,50 μmol/L AlCl3）. The sparingly soluble phosphate could be dissolved into citrate or malate solution,and the dissolved phosphate increased significantly with the concentration of organic acids. It was shown a stronger capacity in Win for the plant utilization of sparingly soluble phosphate, the dissolution of sparingly soluble phosphate by anion components, and the secretion of organic acids from roots. These results indicated that the secretion of organic acid from roots under Al stress was an available mechanism for mobilization and utilization of sparingly soluble phosphate in rye.

关 键 词： 黑麦 难溶性磷 活化 铝 有机酸 分泌

领　　域： [生物学]