Azolla domestication towards a biobased economy?

New Phytol. 2014 May;202(3):1069-1082. doi: 10.1111/nph.12708. Epub 2014 Feb 4.


Due to its phenomenal growth requiring neither nitrogen fertilizer nor arable land and its biomass composition, the mosquito fern Azolla is a candidate crop to yield food, fuels and chemicals sustainably. To advance Azolla domestication, we research its dissemination, storage and transcriptome. Methods for dissemination, cross-fertilization and cryopreservation of the symbiosis Azolla filiculoides-Nostoc azollae are tested based on the fern spores. To study molecular processes in Azolla including spore induction, a database of 37 649 unigenes from RNAseq of microsporocarps, megasporocarps and sporophytes was assembled, then validated. Spores obtained year-round germinated in vitro within 26 d. In vitro fertilization rates reached 25%. Cryopreservation permitted storage for at least 7 months. The unigene database entirely covered central metabolism and to a large degree covered cellular processes and regulatory networks. Analysis of genes engaged in transition to sexual reproduction revealed a FLOWERING LOCUS T-like protein in ferns with special features induced in sporulating Azolla fronds. Although domestication of a fern-cyanobacteria symbiosis may seem a daunting task, we conclude that the time is ripe and that results generated will serve to more widely access biochemicals in fern biomass for a biobased economy.

Keywords: Azolla filiculoides; RNAseq; biobased economy; cryopreservation; domestication; fern; sexual reproduction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism
  • Cotyledon / growth & development
  • Crops, Agricultural / economics*
  • Crops, Agricultural / genetics
  • Crops, Agricultural / growth & development*
  • Crops, Agricultural / metabolism
  • Cryopreservation
  • Databases, Genetic
  • Desiccation
  • Ferns / genetics
  • Ferns / growth & development*
  • Ferns / metabolism
  • Fertilization
  • Freezing
  • Gene Regulatory Networks / genetics
  • Germination
  • Metabolic Networks and Pathways / genetics
  • Molecular Sequence Data
  • Organogenesis / genetics
  • Plant Proteins / chemistry
  • Plant Proteins / metabolism
  • Spores / growth & development
  • Symbiosis


  • Plant Proteins