Transcriptional, metabolic, physiological and developmental responses of switchgrass to phosphorus limitation

Plant Cell Environ. 2021 Jan;44(1):186-202. doi: 10.1111/pce.13872. Epub 2020 Oct 7.

Abstract

Knowing how switchgrass (Panicum virgatum L.) responds and adapts to phosphorus (P)-limitation will aid efforts to optimize P acquisition and use in this species for sustainable biomass production. This integrative study investigated the impacts of mild, moderate, and severe P-stress on genome transcription and whole-plant metabolism, physiology and development in switchgrass. P-limitation reduced overall plant growth, increased root/shoot ratio, increased root branching at moderate P-stress, and decreased root diameter with increased density and length of root hairs at severe P-stress. RNA-seq analysis revealed thousands of genes that were differentially expressed under moderate and severe P-stress in roots and/or shoots compared to P-replete plants, with many stress-induced genes involved in transcriptional and other forms of regulation, primary and secondary metabolism, transport, and other processes involved in P-acquisition and homeostasis. Amongst the latter were multiple miRNA399 genes and putative targets of these. Metabolite profiling showed that levels of most sugars and sugar alcohols decreased with increasing P stress, while organic and amino acids increased under mild and moderate P-stress in shoots and roots, although this trend reversed under severe P-stress, especially in shoots.

Keywords: metabolome; nutrient stress; phosphorus; switchgrass; transcriptome.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Gene Expression Profiling
  • Medical Records
  • MicroRNAs / metabolism
  • Panicum / growth & development
  • Panicum / metabolism*
  • Panicum / physiology
  • Phosphorus / deficiency*
  • Plant Roots / growth & development
  • Plant Roots / metabolism
  • Plant Shoots / growth & development
  • Plant Shoots / metabolism
  • RNA, Long Noncoding / metabolism
  • RNA, Plant / metabolism
  • Stress, Physiological

Substances

  • MicroRNAs
  • RNA, Long Noncoding
  • RNA, Plant
  • Phosphorus