摘要 : In order to consider yield changes and some characteristics of corn cv. Jeta reaction to water deficit stress and potassium fertilizer, a randomized complete block design base split plot experiment with three replications was cond... 展开 In order to consider yield changes and some characteristics of corn cv. Jeta reaction to water deficit stress and potassium fertilizer, a randomized complete block design base split plot experiment with three replications was conducted during 2009 at Agricultural Research Station, Islamic Azad University, Tabriz branch, Iran. Water deficit stress in four levels after 50, 90, 130 and 170 mm evaporation from class A in main plot and potassium sulfate in five levels 0, 50, 100, 150 and 200 kg/ha in sub plots. The obtained results indicated that increasing water deficit lead to reduce leaves number, stem diameter, biomass, grain numbers per row, grains weight per ear, 1000 grains weight, leaf area duration, grains effective filling period and grains yield. Increasing application of potassium fertilizer from 0 to 200 kg/ha increased number of leaves, stem diameter and biomass. The highest plant biomass was obtained by irrigation after 50 mm evaporation from head and application potassium fertilizer at the rate 200 kg/ha and the lowest by irrigation after 170 mm evaporation and lack potassium fertilizer. Also, application of 200 kg K/ha increased grains number per row, grains weight per row and 1000 grains weight that increased grains yield. The highest grains yield was 15.9 t/ha resulted in by application potassium fertilizer at the rate of 200 kg/ha and the lowest at lack application fertilizer equal 10 t/ha. Application of 200 kg K/ha increased leaves number, stem diameter, biomass, grains number per row, grains weight per row, 1000 grains weight relation lack application the rate 6.5, 92.49, 66.82, 24.96, 48.4, 13.92%, respectively. Increase in the application of potassium fertilizer caused to augmentation leaf area duration and in this way effective seed filling period find to increase. Base on the results of this experiment, application potassium fertilizer under water deficit condition decreased grains yield from 19.96 to 48.37%. 收起