Effect of plant densities and nitrogen levels on cob yield and quality parameters of sweet corn (Zea mays L. Saccharata) in irrigated ecosystem

A field trail was conducted during kharif 2017-18 to study the effect of plant densities and nitrogen levels on cob yield and quality parameters of sweet corn (Zea mays L. Saccharata) in irrigated ecosystem at Agricultural Research Station, Siruguppa, Karnataka. The soil of the experimental site was medium deep black soil, low in organic carbon, available N, medium in available phosphorus and high in potassium. The experiment consisted of four plant densities viz., S1:1,11,111, S2:74,074, S3:83,333 and S3:55,555 plants ha-1 in main plots and with four nitrogen levels F1:150 kg N ha-1, F2:187.5 kg N ha-1, F3:225 kg N ha-1 and F4: 262.5 kg N ha-1 in sub plots. The Sugar-75 hybrid was used in the trial. The experimental results revealed that among the plant densities, higher plant density (1,11,111 plants ha-1) recorded significantly higher fresh cob yield (13350 kg ha-1) compared to other plant densities. Whereas quality parameters, protein (10.31%), oil (6.93%), reducing (3.36%) and non-reducing sugar (18.36%) contents in sweet corn were significantly higher with plant density of 55,555 plants ha-1. Among nitrogen levels, application of 262.5 kg N ha-1 registered significantly higher fresh cob yield (13866 kg ha-1), protein (10.39%), starch (47.97%), oil (7.07%), reducing (3.48%) and non-reducing sugar (18.49%) contents in sweet corn compared to 150 N kg ha-1.