Abstract
Effect of the rice crop canopy was studied as regards the availability of solar radiation toAzolla (Azolla pinnata R Brown) and its growth and nitrogen fixation while using late inoculation of 0·5 or 1 t fresh fronds/ha during both wet and dry seasons. The higher leaf area index of rice due to increasing rates of fertilizer-N application caused more shading to theAzolla plants and reduced their biomass and fixed nitrogen, irrespective of the season. The biomass and nitrogen content ofAzolla were higher using an inoculum of 1 t/ha than using 0·5 t/ha.Azolla growth and fixed nitrogen in treatments of 40 and 80 kg N/ha urea were comparatively higher when rice seedlings were transplanted with double narrow-row spacing than that of normal spacing.
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Singh, D.P., Singh, P.K. Influence of rice crop canopy on growth and nitrogen fixation of water fernAzolla pinnata . Proc. Indian Acad. Sci. 98, 209–214 (1988). https://doi.org/10.1007/BF03053590
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DOI: https://doi.org/10.1007/BF03053590