The effects of optimal potassium nourishment and different irrigation management on the decreased consumptive used water in corn

The corn is one of efficient crop in the living of human being. With regard to the arid and semi-arid condition of our country and the presence of dry periods in recent years, this research work was conducted in order to investigate the positive role of potassium in declining the negative effects of deficit irrigation and application of suitable irrigation method. This experiment was conducted as Randomized Complete block Design on corn Plant Line-704 single cross in form of split plots in Zarghan city in the year 2010. The main factor was irrigation frequency: 1. The complete irrigation during the whole growing season, 2. The alternate irrigation in every other day, except in germination and flowering stages, 3. The alternate irrigation in every other days in the whole growing season. And the minor factor was the application of potassium sulfate fertilizer in four levels (0.00, 100, 200 and 300kg.ha). The results showed that the alternate irrigation treatment of every other days except in germination and flowering stages, caused signification increase in grain yield(4.9318 t.ha-1), while constant irrigation of every other days did not have a significant effect on grain yield (2.6453 t.ha-1). With regard to the different levels of potassium sulfate effect on leaf-area index dry weight of the cob, number of rows in cob, number of grain in row and grain yield had a significant statistical difference. Application of 300kg potassium sulfate per hectar has caused the highest leaf - area index(5.8178),cob diameter(4.437cm), dry weight of the cob(0.163gr.m), number of row per cob(14.883), number of grain per row(28.478), harvest index(23.0785%) and grain yield(4.41 t.ha-1).The interaction effect of every other day ś irrigation except during germination and flowering stages had the highest grain yield through the application of 300 kg potassium fertilizer per ha (5.974 t.ha-1).