QTL analysis for sugar-regulated leaf senescence supports flowering-dependent and -independent senescence pathways

New Phytol. 2010 Jan;185(2):420-33. doi: 10.1111/j.1469-8137.2009.03072.x. Epub 2009 Oct 29.

Abstract

*The aim of this work was to determine the genetic basis of sugar-regulated senescence and to explore the relationship with other traits, including flowering and nitrogen-use efficiency. *Quantitative trait loci (QTLs) for senescence were mapped in the Arabidopsis Bay-0 x Shahdara recombinant-inbred line (RIL) population after growth on glucose-containing medium, which accelerates senescence. The extent of whole-rosette senescence was determined by imaging the maximum quantum yield of photosystem II (F(v)/F(m)). *A major QTL on the top of chromosome 4 colocalized with FRI, a major determinant of flowering. This QTL interacted epistatically with a QTL on chromosome 5, where the floral repressor FLC localizes. Vernalization accelerated senescence in late-flowering lines with functional FRI and FLC alleles. Comparison with previous results using the Bay-0 x Shahdara population showed that rapid rosette senescence on glucose-containing medium was correlated with early flowering and high sugar content in compost-grown plants. In addition, correlation was found between the expression of flowering and senescence-associated genes in Arabidopsis accessions. However, an additional QTL on chromosome 3 was not linked to flowering, but to nitrogen-use efficiency. *The results show that whole-rosette senescence is genetically linked to the vernalization-dependent control of flowering, but is also controlled by flowering-independent pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / physiology
  • Cellular Senescence / genetics*
  • Cellular Senescence / physiology
  • Chromosomes*
  • Epistasis, Genetic
  • Flowers / genetics*
  • Flowers / growth & development
  • Genes, Plant*
  • Glucose / metabolism
  • Nitrogen / metabolism
  • Photosystem II Protein Complex / genetics
  • Photosystem II Protein Complex / physiology
  • Plant Leaves / genetics*
  • Plant Leaves / physiology
  • Quantitative Trait Loci*

Substances

  • Photosystem II Protein Complex
  • Glucose
  • Nitrogen