Effect of Biofertilizers on Crop Yield and Soil Available Nutrients of Rice and Maize in Alfisols of Nagarjuna Sagar Left Canal Command Area of Andhra Pradesh, India

On farm field experiment with the participation of farmers the effect of biofertilizers on soil fertility and crop yield of rice and maize was studied in Alfisols during Kharif 2006 and Rabi 2006-07, respectively at Pilot area Ganapavaram of Nagarjuna Sagar Project left canal command under area located in Kodad mandal of Nalgonda district, Andhra Pradesh was conducted in A.P. Water Management Project affiliated to Acharya N.G. Ranga Agricultural University, Hyderabad. In rice the high yield was observed in RDF+application of biofertilizers (6800 kg ha^-1) followed by Farmers practice (6600 kg ha^-1). Similarly in maize the high yield was recorded in RDF+biofertilizers (6500 kg ha^-1) followed by 6150 kg ha^-1 in 25% low RDF+bio fertilizers. There was no difference in pH when compared to initial soil status but there is slight decrease in EC. The change in organic carbon content was more in rice treatments than maize, the OC content was decreased in all treatments when compared to initial status. Increasing the availability of N was more in RDF+Biofertilizers followed by farmers practice in Kharif rice and decreased in 25% low RDF+Biofertilizers and RDF. Where as in Rabi maize the availability of N content was decreased. The P availability was increased in all the treatments in Kharif rice, where as in Rabi maize there was no much difference. K availability was decreased more in RDF followed by 25% low RDF+application of biofertilizers both in rice and maize.