Production Potential of Sweet Corn ( Zea mays) As Influenced by Varying Plant Densities and Nitrogen Levels.

Production potential of Sweet corn ( Zea mays) as influenced by varying plant densities and nitrogen levels Spandana Bhatt.P, Yakadri.M, Sivalakshmi.Y and Vijaykumar,B. Department of Agronomy, College of Agriculture Acharya N.G. Ranga Agricultural University, Rajendranagar, Hyderabad, 500030 ABSTRACT A field experiment was conducted during rainy season, 2009 at Agricultural Research Institute, Rajendranagar, Hyderabad. The experiment was conducted on a clay loam soil of medium fertility with twelve treatment combinations including three levels of plant densities 66,666(P1), 80,000(P2), 1,00,000(P3) plants ha-1 and four nitrogen levels 120(N1), 160 (N2), 200 (N3), 240(N4) kg ha-1 in randomized block design with factorial concept in three replications. Among the growth characters, plant height, LAI and days to 50 % flowering increased with increase in plant density. Dry matter production and crop growth rate were found increased with increased plant densities from 66,666 to 800,00 plants ha-1 and then showed decreased trend with higher plant density of 1,00,000 ha-1. Lower plant density of 66,666 ha-1 had significantly higher cob length, cob girth, fresh cob weight (gm per cob),kernels per cob and 100 kernel weight when compared to higher plant densities of 80,000 and 1,00,000 ha-1. Plant density of 80,000 ha-1 gave maximum green cob yield of 14,159 kg ha-1 where as 1,00,000 ha-1 produced higher green fodder yield of 18,532 kg ha-1. Nitrogen uptake at harvest was maximum with 80,000 plants ha-1. Growth characters like plant height, LAI, dry matter accumulation increased due to increased level of nitrogen application from 120 to 240 kg ha-1.All the yield attributes such as cob length, cob girth, fresh cob weight, number of kernels per cob and 100 kernel weight were found maximum at 240 kg N ha-1 level than at the remaining nitrogen levels. The treatment combination of P2N4 (80,000 plants ha-1 with application of 240 kg N ha-1) gave maximum cob yield (18,090 kg ha-1), net returns and B:C ratio (4.25) followed by P2N3. The results suggest for adoption of sweet corn hybrid with plant density of 80,000 ha-1 along with the application of 240 kg N ha-1 in clay loam soils with low available status of nitrogen during rainy’ season for obtaining higher yield, net returns and B:C ratio.