THE EFFECT OF SOWING DATE ON YIELD AND YIELD COMPONENTS AND SEED QUALITY OF CORN (Zea mays L.)

The seed yield of corn (Zea mays L.) consists of different proportional contributions of the effective factor in all growth stages from emergence to maturity. The aim of this study was to investigate the effects of two sowing dates on agronomic and seed quality traits such as oil, protein and starch content of three commercial corn cultivars (31G98, NK-Arma and Aveline). Experiments were carried out at two different sowing dates (30 of April and 26 of May) one month between sowing dates in the Aegean region of Turkey during 2012 and 2013 summer growth periods. The experiment was a randomized block design with three replications. The results of this study showed that sowing date had statistically effected on thousand seed weight, the seed number in corncob, corncob length, seed yield, ash, oil, protein, starch contents of corn seed. In particular, it was revealed that thousand seed weight, the seed number in corncob, corncob length, seed yield, protein, ash and oil contents of seed were decreased with the delaying sowing date due to decreasing the time of growth period and seed filling. On the other hand, starch content of seed was increased by delaying sowing date in both years. The highest seed yield was obtained from Aveline corn cultivar in late sowing date in both years because of having high thousand seed weight. The percentage of decreased in terms of protein was to highest in Aveline cultivar with the delaying sowing date. It was suggested that eventough the Aegean climate has a long growing period and is a suitable environment for second crop corn growth, the selection of cultivar is very important to grown in terms of seed yield in late sowing date because of the fact that plant can be exposed to inappropriate excessive temperature during the vegetative period in late sowing date in Aegean region.