Abstract

Field trials were conducted during Sornovari 1977 Samba 1977-78 seasons with the rice varieties ADT-31 and IR-20, Blue green algae at the rate of 10 kg/ha were apolied to the soil on 7th day after transplantation of the rice crop along with different levels of nitrogen. The composite culture blue green algae consisted of Aulosire, Anabaena, Nostoc, Tolypothrix, Plectonema and Aphanothece. The different treatments were: (1) control (no nitrogen and no blue green algae) (2) Blue green aigee (BGA) alone (3) 25 kg N/ha (4) 25 kg N/ha+BGA (5) 50 kg N/ha (6) 50 kg N/ho+BGA (7) 75 kg N/ha (8) 75 kg N/ha + BGA (9) 100 kg N/ha (10) 100 kg N/ha BGA. Increased grain yield was obtained due to inoculation with blus green algal. The yield obtained with every level of fertilizer nitrogen with aigal supplemen tation was comparable to that in the next higher level of nitrogen.

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