Abstract

                                A field experiment was carried out at Agricultural College Farm, Mahanandi in Kurnool district of Andhra Pradesh to study the effect of different levels of potassium and green manure on yield, dry matter production, content, uptake of potassium, available K and potassium use efficiency of rice during kharif 2015. The results revealed that the yield, dry matter production, content, uptake of potassium, available K and potassium use efficiency were significantly increased with increase in K fertilizer application and also due to green manure incorporation. The highest yield, dry matter production, content and uptake of potassium, available K were obtained with incorporation of green manure (Dhaincha @ 5 t ha-1) +120 kg K2 O ha-1 which was on par with (Dhaincha @ 5 t ha-1) +80 kg K2 O ha-1and (Dhaincha @ 5 t ha-1)+40 kg K2 O ha-1. Among all the treatments the highest KUE was observed with T6 ((Dhaincha @ 5 t ha-1) +40 kg K2 O ha-1) followed by T7 ((Dhaincha @ 5 t ha-1) + 80 kg K2 O ha-1) and T8 ((Dhaincha @ 5 t ha-1) +120 kg K2 O ha-1). Among the levels of K fertilizer, the highest potassium use efficiency was recorded at 100% RDK (80 kg K2 O ha-1) followed by 150% RDK (120 kg K2 O ha-1)

Key words : Rice, Available K, Green Manure, Potassium use efficiency, Uptake of Potassium