ABSTRACT
Integrated use of organic and inorganic fertilizers can improve crop productivity and sustain soil health and fertility. The present research was conducted with an objective to study the influence of application of farmyard manure in combination with three levels of chemical fertilizers [80 : 40 : 30, 120 : 60 : 45 and 160 : 80 : 60 kg N, P2O5 and K2O ha−1, respectively] on yield and yield components of irrigated lowland rice. The experiment was conducted in split-plot design during the rainy season with and without farmyard manure as main plots and three inorganic fertilizer levels as subplots. Data on grain and straw yield, number of tillers, panicle length, filled grains per panicle, 1000-grain weight and nutrient uptake were collected. The results showed that application of farmyard manure at 10 t ha−1 increased grain yield of rice by 25% compared to no farmyard manure control. Similar observations were also made on straw yield, tiller number, filled grains per panicle, and 1000-grain weight. There were significant interactions between farmyard manure and inorganic fertilizer treatments. The beneficial effects of application of farmyard manure were not enhanced at increased rates of application of inorganic fertilizers. However, the highest grain yield of rice was obtained with the application of farmyard manure at 10 t ha−1 and inorganic fertilizer at 120 : 60 : 45 kg N, P2O5 and K2O ha−1. The increased grain yield was due mainly to increased nutrient uptake and number of tillers, filled grains per panicle and 1000-grain weight.
ACKNOWLEDGMENTS
This research was funded by the Potash and Phosphate Institute of Canada (India Program). We thank Dr. G. Dev, Professors V. Santaram and M. M. Hussain for their support. We also wish to thank the farm manager and staff of the College Farm for providing facilities and technical assistance.