Biologia Plantarum

, Volume 54, Issue 4, pp 647–652

Metabolic engineering using mtlD gene enhances tolerance to water deficit and salinity in sorghum

  • M. Maheswari
  • Y. Varalaxmi
  • A. Vijayalakshmi
  • S. K. Yadav
  • P. Sharmila
  • B. Venkateswarlu
  • M. Vanaja
  • P. Pardha Saradhi
Original Papers

DOI: 10.1007/s10535-010-0115-y

Cite this article as:
Maheswari, M., Varalaxmi, Y., Vijayalakshmi, A. et al. Biol Plant (2010) 54: 647. doi:10.1007/s10535-010-0115-y

Abstract

Sorghum bicolor L. Moench cv. SPV462 was transformed with the mtlD gene encoding for mannitol-1-phosphate dehydrogenase from E. coli with an aim to enhance tolerance to water deficit and NaCl stress. Transgene (pCAM mtlD) integration and expression were successfully confirmed by PCR, Southern, RT-PCR and Western analysis. Segregation analysis based on germination of T0 seed on hygromycin-supplemented medium revealed an expected Mendelian ratio 3:1 in lines 5, 72 and 75. Retention of leaf water content was remarkably higher in transgenic leaf segments when exposed to polyethylene glycol 8000 (−2.0 MPa), as compared to the untransformed controls. Another significant finding is that the transgenics maintained a 1.7 to 2.8 fold higher shoot and root growth, respectively, under NaCl stress (200 mM) when compared to untransformed controls. These results demonstrate that engineering mannitol biosynthetic pathway into sorghum can impart enhanced tolerance to water deficit and salinity.

Additional key words

biolisticsmannitolmtlD geneSorghum bicolortransformation

Abbreviations

mtlD gene

mannitol-1-phosphate dehydrogenase gene

PCR

polymerase chain reaction

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • M. Maheswari
    • 1
  • Y. Varalaxmi
    • 1
  • A. Vijayalakshmi
    • 1
  • S. K. Yadav
    • 1
  • P. Sharmila
    • 2
  • B. Venkateswarlu
    • 1
  • M. Vanaja
    • 1
  • P. Pardha Saradhi
    • 2
  1. 1.Division of Crop SciencesCentral Research Institute for Dryland AgricultureSantoshnagar, HyderabadIndia
  2. 2.Department of Environmental BiologyUniversity of DelhiNew DelhiIndia