The effect of planting pattern on phenological and morphological traits of sunflower in Zahak region, Sistan, Iran

The current study was conducted to investigate planting pattern effect on some morphological and phenological traits of sunflower. The experiment was carried out based on randomized complete block design in factorial with three replications at the Agriculture and Natural Resources Research Station, Zahak, Sistan, Iran in 2014-2015. Experimental factors were consisted as interspacing planting rows of 30, 40, 50, 60 cm and inter-spacing planting rows of 10, 15, 20, 25 cm. The effects of inter-spacing planting rows on all morphological and phenological traits except number of leaves per plant and days to flowering were significant. The effect of inter-spading planting rows was significant on all traits. Interaction of inter- and intra-spacing planting rows was significant only in number of leaves. Increasing in density caused maturity and flowering enhancement and decreased flowering period. Stem and head diameter and plant height increased by intra- and inter spacing planting rows increment. Optimal planting density would be 60 cm as inter- and 25 cm as intra spacing rows to achieve maximum yield in sunflower in this region.