Effect of Ascorbic Acid and Harvest Date on Various Traits and Yield Loss of Corn

Experiment was conducted to study the effect of ascorbic acid and harvest date on various traits and yield of corn, an at the College of Agriculture Research Station, Tikrit University. The experiment consisted of three local varieties of corn (Baghdad, Sara, and Fajir), three concentrations of ascorbic acid (0, 100, and 200 mg L^-1), and three harvesting date (30, 40, and 50 days) after pollination. There were no significant differences among varieties for studied traits. The ascorbic acid 200 mg L^-1 resulted in significantly higher broken grains percentage and broken grain ( 2.587% and 180.09 kg h^-1, respectively). Furthermore, this treatment produced higher net grain yield of 6790 kg h^-1. Harvest date had significant effect on all studied traits and moisture percentage was decreased significantly by 15% between the first and third dates of harvest and remaining grains percentage in cob after shelled and its weight were increased. Percentage of broken grains was increased from 0.771 to 3.563%, weight increased from 54.23 to 232.94 kg h^-1 and total grain loss increased from 1.301 to 6.972% as harvesting early from 50 to 30 days after pollination, while the net grain yield was decreased from 7203 to 6080 kg h^-1for the same two dates, respectively.