The effect of drought on the growth and yield of "Dogu-88" winter wheat variety was investigated in this field experi-ment using plot covers. Fully irrigated (FI), rainfed (R), early drought (ED), late drought (LD) and continuous drought (CD) treat-ments were studied under Erzurum conditions. ED decreased grain number per unit area by 44.4 %, 1000 kernel weight by 6.9 % and grain yield by 40.6 % compared with FI. A rapid senescence of green tissues in LD treatment also led to shorter green area duration (27.5 days), lighter 1000 kernel weight (3.8 g) and lower grain yield (24.0 %). CD treatment decreased grain number per unit area by 54.9 %, 1000 kernel weight by 19.9 % and grain yield by 65.6 % compared with FI. Variations in grain yield depended mainly on the effects of treatments on grain number per unit area. ED limited primarily grain number per unit area while LD affected kernel weight. The negative effect of ED on grain yield was more significant than that of LD.

The effect of drought on the growth and yield of "Dogu-88" winter wheat variety was investigated in this field experi-ment using plot covers. Fully irrigated (FI), rainfed (R), early drought (ED), late drought (LD) and continuous drought (CD) treat-ments were studied under Erzurum conditions. ED decreased grain number per unit area by 44.4 %, 1000 kernel weight by 6.9 % and grain yield by 40.6 % compared with FI. A rapid senescence of green tissues in LD treatment also led to shorter green area duration (27.5 days), lighter 1000 kernel weight (3.8 g) and lower grain yield (24.0 %). CD treatment decreased grain number per unit area by 54.9 %, 1000 kernel weight by 19.9 % and grain yield by 65.6 % compared with FI. Variations in grain yield depended mainly on the effects of treatments on grain number per unit area. ED limited primarily grain number per unit area while LD affected kernel weight. The negative effect of ED on grain yield was more significant than that of LD.