The Effects of Planting date and Plant Spacing on Yield and Yield Components of Fennel

In order to study the effect of planting date and plant spacing on yield and yield components of fennel, an experiment was conducted in a split plot in a randomized complete block design with three replications at the Research Farm in Ilam, Iran in 2011-2012 cropping season. Experimental factors such as planting date at 3 levels (5 March, 20 March and 5 April) were chosen as main plot and plant spacing at four levels (2, 3, 4 and 5 cm) were assigned as subplot. Planting date had significantly affected on the number of primary branches, number of secondary branches, number of grain per head and grain yield. The highest number of primary branches (7.5 branches), number of grain per head (199.8 grain) and grain yield (704.7 kg.ha-1) was gained in planting date of 5 March. Maximum number of head per plant (22.3 head), number of grain per head I (195 grain) and grain yield (702 kg.ha-1) was obtained at plant spacing of 3 cm. Interaction effect between planting date and plant spacing on number of primary branches, 1000-grain weight and grain yield was significant. The highest number of primary branches, 1000-grain weight and grain yield were obtained at planting date of 5 March and plant spacing of 4 cm. The results of this study, early planting of fennel had better conditions of vegetative and reproductive growth and better yield, and plant spacing of 3 cm had more impact on grain yield in the Ilam region.