Effect of sowing date in yield seed and oil of three sunflower genotypes

Abstract

A field experiment was conducted at Abu-Ghraib research station , Baghdad, Iraq during 2001 season The objectives were to study the effect of sowing dates on the performance of three sunflower genotypes . A split-plot lay in a randomized complete block design with three replications were used . Five sowing dates ( 16th Jan , 4th , 14th and 26th of Feb. and the 15th of March ) were assigned to main plots , where as genotypes (Manon,Pan7392,Euroflor) were assigned to sub-plots .Any delay in sowing dates after the 16th Jan . Hastened the physiological processes of the developmental stages of the crop . and reflect , the effects of environmental factors such as ( higher temperature , longer photoperiod and lower relative humidity ) , consequently the optimum periods of the life cycle of the crop was shortened . Sowing as early as mid of January maximized seed yield to 4556 Kg/ha , oil yield 2127.2 Kg/ha , at this planting date . Oil concentration , however , was the highest 50% at the last planting date ( march the 15th) . gave the genotype Pan 7392 the superiority of producing higher seed yield 4130.7 , and oil yielded 1962.3 Kg/ha , the other two genotypes . Euroflor , however , produce more oil content 48.9 % compared with Pan 7392 47.6% and Manon 45.5% genotypes .Interactions between genotypes and sowing dates were also detected . genotypes Pan 7392 gave the highest seed yield 5001.75 Kg/ha and contain more oil 2359.01 Kg/ha when sowing at the 16th of January .