Study of plant density and irrigation intervals on forage yield and some physiological traits in forage sorghum

Forage yield and some physiological traits of a forage sorghum cultivar (Speed feed) was studied in three irrigation intervals 4, 7 and 10 days in the Azad university of Iranshahr in 2003 cropping season. The experimental deasign was split plot based on randomized complete blocks with three replications. Irrigation intervals were studied in main plots and plant density of 8, 12 and 15cm were assigned to sub-plots. Planting was carried out in May 5, 2003. Different physiological traits associated to forage yield and its components were measured durring growing season. Analysis of variance and mean comparison were porformed using the principles of split plot design and DMRT, respectively. The best irrigation intervals and plant density determined. In this expriment the best irrigation interval, were 4 and 7 days and the best plant density was 12cm. Results indicated that fresh forages are in the same group as irrigation interval, of 4 and 7 days, and the best plant density was 12cm. However, after drying the dry forage at first irrigation level and the second plant density level (37130 kg/ha) was the highest.