Overexpression of Arabidopsis FLOWERING LOCUS T (FT) gene improves floral development in cassava (Manihot esculenta, Crantz)

PLoS One. 2017 Jul 28;12(7):e0181460. doi: 10.1371/journal.pone.0181460. eCollection 2017.

Abstract

Cassava is a tropical storage-root crop that serves as a worldwide source of staple food for over 800 million people. Flowering is one of the most important breeding challenges in cassava because in most lines flowering is late and non-synchronized, and flower production is sparse. The FLOWERING LOCUS T (FT) gene is pivotal for floral induction in all examined angiosperms. The objective of the current work was to determine the potential roles of the FT signaling system in cassava. The Arabidopsis thaliana FT gene (atFT) was transformed into the cassava cultivar 60444 through Agrobacterium-mediated transformation and was found to be overexpressed constitutively. FT overexpression hastened flower initiation and associated fork-type branching, indicating that cassava has the necessary signaling factors to interact with and respond to the atFT gene product. In addition, overexpression stimulated lateral branching, increased the prolificacy of flower production and extended the longevity of flower development. While FT homologs in some plant species stimulate development of vegetative storage organs, atFT inhibited storage-root development and decreased root harvest index in cassava. These findings collectively contribute to our understanding of flower development in cassava and have the potential for applications in breeding.

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Flowers / genetics
  • Flowers / metabolism*
  • Gene Expression Regulation, Plant / genetics
  • Gene Expression Regulation, Plant / physiology
  • Manihot / genetics
  • Manihot / growth & development*
  • Manihot / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / growth & development*
  • Plants, Genetically Modified / metabolism*

Substances

  • Plant Proteins

Grants and funding

The production of the cassava transgenic lines was supported by grants from the Rockefeller Foundation and internal funds of the Max Planck Society. Work on characterizing the lines was supported by the Next Generation (NEXTGEN) Cassava project at Cornell University, which is supported by a grant from the Bill & Melinda Gates Foundation and the Department for International Development of the United Kingdom. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.