植物营养与肥料学报2010,16(6)：1373-1378 Plant Nutrition and Fertilizer Science
低磷胁迫对豆幼苗叶片光合特性及
根系生理特性的影响
曹翠玲，毛圆辉，曹朋涛，刘建朝，杨向娜
（西北农林科技大学生命科学学院，陕西杨凌712100）
摘要：利用营养液培养方法研究了虹豆幼苗对磷胁迫的生理响应。结果表明，磷胁迫下虹豆根系最大根长增加 43%，侧根数月增加33%，根系体积增加；但是缺磷时叶片面积变小，且发育延迟。缺磷时虹豆幼苗根系活力和根系表面酸性磷酸酶活性分别是全磷培养植株的2.3和1.7倍；与供磷植株相比，缺磷植株光合速率和蒸腾迷率均下降30%；气孔器变小，气孔密度减少（减少20%）。磷胁迫下虹豆十物质累积量显着降低，缺磷主要影响了地上
部分干物质累积，而根系十物质累积几乎不变，因此根冠比增大。磷胁迫对地上的影响大于对根系的影响。关键词：磷胁迫；光合特性；根系生理；酸性磷酸酶活性
中图分类号：S643.4；Q945.78
文献标识码：A
文章编号：1008505X(2010)06137306
Effectofphosphorousstressonphotosynthesisrateandrootphysiologica
characteristicofcowpeaseedlings
CAO Cui-ling, MAO Yuan-hui, CAO Peng-tao, LIU Jian-chao, YANC Xiang-na
（Collegeof LifeSciences，Northeest A&F University，Yangling，Shaanxi712100China）
Abstract : Effects of phosphorus stress on some physiological indexes of Vigna unguiculata (Linn. ) Walp. were stud-ied by hydroponic culture method. The results showed that the main root length under the no phosphorus application treatment (LP) was about 43% longger than that of the control ( HP), the lateral root number increased by 33% compared with the control, and the root volume was raised, while the leaf area reduced when the culture solution had no phosphate. When there was no phosphorus supplied, the root activity and secreted acid phosphatase were increased to 2. 3 and 1.7 times of those of the phosphorus application treatment, respectively. Compared with the control, both the photosynthetic rate and the transpiration rate decreased by 30%. Under the phosphorus deficiency the dry mass lowered remarkably, and the size of stomata became smaller and stomata density decreased. These re-sults showed that the phosphorus deficiency affected the shoot dry mass accumulation and almost had no effects on ac cumulation of root dry mass. Phosphorus deficiency had more negative effects on shoot than on root.
Key words: phosphorous deficiency; photosynthesis; root physiological characteristic; secreted acid phosphatase
磷在植物细胞生物大分子的构建和所有重要代谢过程中起着极其重要的作用。据推算，到2040年(或2060年)将只剩下一半（相对于20世纪末）磷贮备量]。全世界13.19×10*hm耕地中约有43% 缺磷[3]。在我国有2/3的耕地缺磷，缺磷土壤面积约为7266.67×10*hm2[3]。即使土壤中全磷含量高但并不意味着磷素供应充足，因为许多农田中磷素大部分是以迟效性状态存在。有研究表明，肥料中
收稿日期：2009-09-08
接受日期：2010-06-10
80%～90%的磷都被土壤颗粒所吸附，致使那些没有特殊适应性的植物不能利用这些被吸附的磷14]。因此，急需了解作物对低磷条件的生理生化响应机制，进而采用基因工程等生物技术手段，修饰或改良作物基因，获得高效利用磷的作物品种。对此，人们开展了磷素对植物叶片解剖结构的影响(5-6)；低磷条件下菜豆根构型的变化[；不同磷效率小麦品种的光合特性及其生理机制[*]；从磷累积量角度研究
作者简介：曹翠玲（1960一），女，陕西用县人，博士，教授，主要从事模物抗早生理和养分生理的研究。E-mail：cuilingcao@tom，com 万方数据