Vance Carroll P, Uhde-Stone Claudia, Allan Deborah L
USDA, Agricultural Research Service, Plant Science Research Unit, University of Minnesota 1991 Upper Buford Circle, St Paul, MN 55108, USA.
Departments of Agronomy and Plant Genetics, University of Minnesota 1991 Upper Buford Circle, St Paul, MN 55108, USA.
New Phytol. 2003 Mar;157(3):423-447. doi: 10.1046/j.1469-8137.2003.00695.x.
Phosphorus (P) is limiting for crop yield on > 30% of the world's arable land and, by some estimates, world resources of inexpensive P may be depleted by 2050. Improvement of P acquisition and use by plants is critical for economic, humanitarian and environmental reasons. Plants have evolved a diverse array of strategies to obtain adequate P under limiting conditions, including modifications to root architecture, carbon metabolism and membrane structure, exudation of low molecular weight organic acids, protons and enzymes, and enhanced expression of the numerous genes involved in low-P adaptation. These adaptations may be less pronounced in mycorrhizal-associated plants. The formation of cluster roots under P-stress by the nonmycorrhizal species white lupin (Lupinus albus), and the accompanying biochemical changes exemplify many of the plant adaptations that enhance P acquisition and use. Physiological, biochemical, and molecular studies of white lupin and other species response to P-deficiency have identified targets that may be useful for plant improvement. Genomic approaches involving identification of expressed sequence tags (ESTs) found under low-P stress may also yield target sites for plant improvement. Interdisciplinary studies uniting plant breeding, biochemistry, soil science, and genetics under the large umbrella of genomics are prerequisite for rapid progress in improving nutrient acquisition and use in plants. Contents I. Introduction 424 II. The phosphorus conundrum 424 III. Adaptations to low P 424 IV. Uptake of P 424 V. P deficiency alters root development and function 426 VI. P deficiency modifies carbon metabolism 431 VII. Acid phosphatase 436 VIII. Genetic regulation of P responsive genes 437 IX. Improving P acquisition 439 X. Synopsis 440.
在全球超过30%的耕地上，磷（P）是作物产量的限制因素。据一些估计，到2050年，世界上廉价磷资源可能会枯竭。出于经济、人道主义和环境原因，提高植物对磷的吸收和利用至关重要。植物已经进化出多种策略，以在有限条件下获取足够的磷，包括对根系结构、碳代谢和膜结构的改变，低分子量有机酸、质子和酶的分泌，以及参与低磷适应的众多基因的表达增强。这些适应在与菌根相关的植物中可能不太明显。非菌根物种白羽扇豆（Lupinus albus）在磷胁迫下形成簇生根，以及伴随的生化变化，例证了许多增强磷获取和利用的植物适应机制。对白羽扇豆和其他物种对磷缺乏反应的生理、生化和分子研究已经确定了可能对植物改良有用的靶点。涉及鉴定低磷胁迫下发现的表达序列标签（EST）的基因组方法，也可能产生植物改良的靶点。在基因组学的大框架下，将植物育种、生物化学、土壤科学和遗传学结合起来的跨学科研究，是快速提高植物养分获取和利用的先决条件。内容 一、引言424 二、磷的难题424 三、对低磷的适应424 四、磷的吸收424 五、磷缺乏改变根系发育和功能426 六、磷缺乏改变碳代谢431 七、酸性磷酸酶436 八、磷响应基因的遗传调控437 九、改善磷的获取439 十、综述440 。
