POTASSIUM USE EFFICIENCY OF MAIZE HYBRIDS

Maize hybrids exhibit better potassium use efficiency (KUE) and utilize soil N in an efficient way, thus reduce input cost and conserve environment. For the screening of hybrids with proper dose of K, experiment were laid out in randomized complete block design with split plot arrangement, randomizing maize hybrids in main plots (H1= Pioneer-3012, H2= Pioneer-3062, H3= Pioneer - 30D55) and K application levels (K0=0, K1=100, K2=150, K3=200 and K4=250 Kg ha -1 ) in subplots with four replications. It was observed that Pioneer-30D55 significantly gave higher KUE (1.94) than Pioneer- 3012 (1.86), yet it was at par with Pioneer-3062 (1.92). K application at all levels significantly increased KUE over control. All K levels except control produced statistically similar KUE. As far as N present in soil after harvest, Pioneer- 30D55, probably due to its efficient root system left minimum N (0.042 %) in the soil and significantly differed with Pioneer-3062 (0.043%) and Pioneer-3012 (0.044%), which also significantly differed with each other. Minimum N %age left in soil after crop harvest (0.046) was observed, when 200 kg K ha -1 was applied which significantly differed with N %age left in soil after harvest crop (0.045) obtained when 250 kg K ha -1 was applied, where as maximum N %age left in soil after harvest (0.042) was recorded in control. It was therefore concluded that Pioneer-30D55 was the most efficient hybrid with similar KUE with respect to K utilization and similar synergistic trend was recorded with N uptake from soil.