Effects of plant density and sowing date on silage yield in early maturing maize sown following wheat harvest

In order to determine the best planting dates and plant densities of maize for using of silage, two early and every early maturity maize cultivars (SC 108 and SC 301) were planted, in three planting dates (22 June, 1 Jul and 11 Jul) in two cropping seasons (2000-2001). Plant densities were 75000, 85000, 95000 and 105000 plants per hectar. A split plot design with threee replications was used. Sowing dates and plant densitties were assigned to main plots and sub plots, respecitively. Two experiments were carried out in two locations, Ghaemshahr (Gharakhyle) and Neka (Bayekola). Silage yield for each plot and each treatment was evaluated. Mean comparisons for silage yield performed using Duncan's Multiple Range Test. The best planting date and plant density were determined for two years. In Neka, for SC301 cultivar, the best plant density was 95000 plants per hectar with average silage yield of 44 t/ha, and for SC108 cultivar, highest silage yield was 41/7 t/ha with 105000 plants per hectar. In Ghaemshahr, for SC301 cultivar, the best plant density was 95000 plants per hectar with average silage yield of 42 t/ha, and for SC108 the highest silage yield was 36/9 t/ha and the best plant density was 105000 plants per hectar. In Neka, the best planting dates for SC108 were 22 Jun and 1 Jul. In Ghaemshahr this cultivar can be planted at 11 Jul. Result showed that SC301 had higher silage yield than SC108 sown following wheat harvest.