Journal of Integrative Agriculture ›› 2013, Vol. 12 ›› Issue (6): 1098-1111.DOI: 10.1016/S2095-3119(13)60329-9

• 论文 • 上一篇    下一篇

Genetic Improvement of Root Growth Contributes to Efficient Phosphorus Acquisition in maize (Zea mays L.)

 ZHANG Yi-kai, CHEN Fan-jun, CHEN Xiao-chao, LONG Li-zhi, GAO Kun, YUAN Li-xing, ZHANG Fu-suo, MI Guo-hua   

  1. Key Laboratory of Plant-Soil Interactions, Ministry of Education/Center for Resources, Environment and Food Security, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, P.R.China
  • 收稿日期:2012-07-30 出版日期:2013-06-01 发布日期:2013-06-09
  • 通讯作者: Correspondence MI Guo-hua, Tel: +86-10-62734454, Fax: +86-10-62731016, E-mail: miguohua@cau.edu.cn
  • 作者简介:ZHANG Yi-kai, Mobile: 13732279586, E-mail: yikaizhang168@163.com
  • 基金资助:

    This work was supported by the National Natural Science Foundation of China (31121062 and 31071852), EU Seventh Framework Programme of European Union (NUECROPS, 222645), and the Special Fund for the Agricultural Profession of China (201103003).

Genetic Improvement of Root Growth Contributes to Efficient Phosphorus Acquisition in maize (Zea mays L.)

 ZHANG Yi-kai, CHEN Fan-jun, CHEN Xiao-chao, LONG Li-zhi, GAO Kun, YUAN Li-xing, ZHANG Fu-suo, MI Guo-hua   

  1. Key Laboratory of Plant-Soil Interactions, Ministry of Education/Center for Resources, Environment and Food Security, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, P.R.China
  • Received:2012-07-30 Online:2013-06-01 Published:2013-06-09
  • Contact: Correspondence MI Guo-hua, Tel: +86-10-62734454, Fax: +86-10-62731016, E-mail: miguohua@cau.edu.cn
  • About author:ZHANG Yi-kai, Mobile: 13732279586, E-mail: yikaizhang168@163.com
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (31121062 and 31071852), EU Seventh Framework Programme of European Union (NUECROPS, 222645), and the Special Fund for the Agricultural Profession of China (201103003).

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摘要： Maize plants adapt to low phosphorus (P) stress by increasing root growth. It is of importance to know the extent to which genetic improvement of root growth can enhance P acquisiton. In the present study, the contribution of root growth improvement to efficient P acquisition was evaluated in two soils using T149 and T222, a pair of near isogenic maize testcrosses which were derived from a backcross BC4F3 population. T149 and T222 showed no difference in shoot biomass and leaf area under normal growth conditions, but differed greatly in root growth. T149 had longer lateral roots and a larger root surface area compared to T222. In calcareous soil, when P was insufficient, i.e., when P was either supplied as KH2PO4 at a concentration of 50 mg P kg-1 soil, or in the form of Phy-P, Ca3-P or Ca10-P, a 43% increase in root length in T149 compared to T222 resulted in an increase in P uptake by 53%, and shoot biomass by 48%. In acid soil, however, when P supply was insufficient, i.e., when P was supplied as KH2PO4 at a concentration of 100 mg P kg-1 soil, or in the form of Phy-P, Fe-P or Al-P, a 32% increase in root length in T149 compared to T222 resulted in an increase in P uptake by only 12%, and shoot biomass by 7%. No significant differences in the exudation of organic acids and APase activity were found between the two genotypes. It is concluded that genetic improvement of root growth can efficiently increase P acquisition in calcareous soils. In acid soils, however, improvements in the physiological traits of roots, in addition to their size, seem to be required for efficient P acquisition.

关键词: P efficiency , roots , low phosphorus , calcareous soil , acid soil , maize

Abstract: Maize plants adapt to low phosphorus (P) stress by increasing root growth. It is of importance to know the extent to which genetic improvement of root growth can enhance P acquisiton. In the present study, the contribution of root growth improvement to efficient P acquisition was evaluated in two soils using T149 and T222, a pair of near isogenic maize testcrosses which were derived from a backcross BC4F3 population. T149 and T222 showed no difference in shoot biomass and leaf area under normal growth conditions, but differed greatly in root growth. T149 had longer lateral roots and a larger root surface area compared to T222. In calcareous soil, when P was insufficient, i.e., when P was either supplied as KH2PO4 at a concentration of 50 mg P kg-1 soil, or in the form of Phy-P, Ca3-P or Ca10-P, a 43% increase in root length in T149 compared to T222 resulted in an increase in P uptake by 53%, and shoot biomass by 48%. In acid soil, however, when P supply was insufficient, i.e., when P was supplied as KH2PO4 at a concentration of 100 mg P kg-1 soil, or in the form of Phy-P, Fe-P or Al-P, a 32% increase in root length in T149 compared to T222 resulted in an increase in P uptake by only 12%, and shoot biomass by 7%. No significant differences in the exudation of organic acids and APase activity were found between the two genotypes. It is concluded that genetic improvement of root growth can efficiently increase P acquisition in calcareous soils. In acid soils, however, improvements in the physiological traits of roots, in addition to their size, seem to be required for efficient P acquisition.

Key words: P efficiency , roots , low phosphorus , calcareous soil , acid soil , maize