Blue Green Algae (BGA)

  •      Blue Green Algae (Cyanobacteria), are the photosynthetic prokaryotes that are frequently considered as predominant diazotrophs in wetland rice systems.
  •     Potential nitrogen-fixing BGA species in the rice fields of India are: Aulosira, Anabaena, Nostoc, Anabaenopsis, Calothrix, Camptylonema, Cylindrospermum, Fischerella, Hapalosiphon, Microchaete, Westiella, Westiellopsis and Tolypothrix.
  •      Average N-fixation in soil through BGA is estimated at 25–30 kg N ha−1.
  • Supplementation of chemical fertilizer with blue green algae could conserve upto 30% of commercial fertilizers
  • Apart from biologically fixed nitrogen and adding organic matter to soil, these organisms excrete growth promoting substances, solubilize insoluble phosphates, improve the fertilizer use efficiency of crop plants.
  • BGA has a ameliorating effects on saline and saline-alkali soils, increasing soil stability and aggregate size, and narrowing down the C:N ratio.