Effect of Blue Green Algae on Yield of RD 23 rice

Abstract

The effect of five strains of blue green algae : Anabaena oryzae, Aulosira sp., Calothrix sp., Nostoc sp. and Tolypothrix sp., on growth and yield of RD 23 rice was studied in a pot experiment in Bangkok. Results of the pot study indicated tha trice yield receiving blue green algae generally, increased around 12 - 26% over the control (no nitrogen). Larger root and shoot dry weights wee obtained with blue green algae inculation. The five strains of blue green algae, plus Anabaena siamensis, biofertilizer, and nitrogen at rts of 0 and 75 kg N/ha were also used to investigate their effects on the performance of RD 23 rice in a field experiment in Khon Kaed. The objective of this study was to select any blue green algae that is suitable for improving rice yield.
In the field experiment, application of 75 kg N/ha significantly increased rice yield as compared to all treatments except Tolypothrix sp. and biofertilizer. No statisticl different was observed among blue green algae, biofertilizer, and the control. It was noted that the Tolypothrix sp. treatment consistently outyielded the control in both experiments.