Constitutive overexpression of the sucrose transporter SoSUT1 in potato plants increases arbuscular mycorrhiza fungal root colonization under high, but not under low, soil phosphorus availability

Elke Gabriel-Neumann, Günter Neumann, Georg Leggewie, Eckhard George

Research output: Contribution to journalArticlepeer-review

32 Citations (Scopus)

Abstract

The sucrose transporter SUT1 functions in phloem loading of photoassimilates in solanaceous plant species. In the present study, wildtype and transgenic potato plants with either constitutive overexpression or antisense inhibition of SUT1 were grown under high or low phosphorus (P) fertilization levels in the presence or absence of the arbuscular mycorrhizal (AM) fungus Glomus intraradices. At a low soil P fertilization level, the extent of AM fungal root colonization was not different among the genotypes. In all plants, the AM symbiosis contributed significantly to P uptake under these conditions. In response to a high soil P fertilization level, all genotypes showed a decrease in AM fungal root colonization, indicating that the expression level of SUT1 does not constitute a major mechanism of control over AM development in response to the soil P availability. However, plants with overexpression of SUT1 showed a higher extent of AM fungal root colonization compared with the other genotypes when the soil P availability was high. Whether an increased symbiotic C supply, alterations in the phytohormonal balance, or a decreased synthesis of antimicrobial compounds was the major cause for this effect requires further investigation. In plants with impaired phloem loading, a low C status of plant sink tissues did apparently not negatively affect plant C supply to the AM symbiosis. It is possible that, at least during vegetative and early generative growth, source rather than sink tissues exert control over amounts of C supplied to AM fungi.

Original languageEnglish
Pages (from-to)911-919
Number of pages9
JournalJournal of Plant Physiology
Volume168
Issue number9
DOIs
Publication statusPublished - Jun 15 2011

Keywords

  • Arbuscular mycorrhiza
  • Carbohydrate partitioning
  • Phloem loading
  • Phosphorus nutrition
  • Sucrose transporter SUT1

ASJC Scopus subject areas

  • Physiology
  • Agronomy and Crop Science
  • Plant Science

Fingerprint

Dive into the research topics of 'Constitutive overexpression of the sucrose transporter SoSUT1 in potato plants increases arbuscular mycorrhiza fungal root colonization under high, but not under low, soil phosphorus availability'. Together they form a unique fingerprint.

Cite this