The effect of plant density on seed yield, some yield components and quality characteristics of corn under second crop condition

This study was carried out in Aydın/Söke province (SÖKE TAYEM) in 2019 in order to see the performance of corn varieties at different frequencies under the second crop conditions. As a material of the study, May-Capuzi, Syngenta-Sy Zoan, Dekalp-DKC 6664 and Pioneer P2088 varieties and 5 different row spacing's (12 cm, 14 cm, 16 cm, 18 cm, 20 cm) were determined. Plant height, first cob height, cob height, cob weight, grain number in cob, grain weight in cob, hundred grain weight, stalk thickness, cob diameter, grain yield values were measured. In addition, protein, starch, fat and fiber ratios were measured in the grain. According to the results of our research, it was found that it would be correct to make the frequency choices according to the reasons of growing the corn varieties grown under the second crop conditions. In some yield components (stub height, stub weight, kernel count, kernel weight, hundred kernel weight, and stalk thickness, stub and knockout diameter, knockout weight) 20 cm row distance showed the highest values. In addition, protein, starch, fat and fiber ratio values were measured to reach the maximum level at the lowest frequency value (20 cm). It is concluded that if breeding is planned for these features (larger stub or coarse grains, high protein, starch or fat ratio, etc.), it will be appropriate to increase the row spacing. However, if the cultivation is made for the characteristics such as plant height, height of the first cob or grain yield per area (high green grass or grain yield), it is determined that the average obtained is increased with frequency and the highest values are measured at a distance of 12 cm row. Key Words: Corn, plant frequency, seed yield, seed quality