Azolla plant surface. Coloured scanning electron micrograph (SEM) of the surface of an Azolla (water fern) plant. This plant has a symbiotic relations

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Azolla plant surface. Coloured scanning electron micrograph (SEM) of the surface of an Azolla (water fern) plant. This plant has a symbiotic relationship with Anabaena cyanobacteria, where the cyanobacteria doubles the rate of photosynthesis and fulfils the nitrogen requirements of the plant. Both these factors give the water fern a competitive advantage over other water plants, a factor spotted by the Chinese 2000 years ago. The Anabaena-Azolla association is used as a green manure for rice crops. Anabaena is a filamentous organism, which, apart from vegetative cells, forms heterocysts and akinetes.

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Size: 3543px × 4961px
Photo credit: © STEFAN DILLER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, adaptation, adapted, anabaena, azolla, biological, biology, botanical, botany, coloured, cyanobacteria, cyanobacterium, evolution, evolutionary, false-coloured, fern, fixation, flora, leaf, microbiological, microbiology, mutualism, mutualistic, nature, nitrogen, photosynthesis, photosynthetic, plant, sem, surface, symbiosis, symbiotic, water