The effects of different sowing depth on grain yield and some grain yield components in wheat ( Triticum aestivum L.) cultivars under dryland conditions

and yield components for wheat cultivars during 2004-2006 at one site in Van Province in Eastern Turkey. Grain yield and yield components were found to positively correlate with coleoptile length, with marked declines observed in grain yield and yield components among varieties with shorter coleoptiles in deepest sowing. Wheat sown at 5 cm gave greater yields than wheat sown at 3, 7 and 9 cm by 19.9, 22.3 and 62.5%, respectively. The highest grain yield (2.98 T ha-1) was obtained with the Alparslan cultivar sown at a depth of 5 cm. Grain yield of all varieties tested was drastically reduced when sown at depths of 9 cm, with the exception of the local Tir and Alparslan varieties, both of which, when compared to the other varieties tested, had longer coleoptiles.