Response of Safflower (Cartharrus tinectorius L.) to Sowing Dates in Khorramabad Climatic Conditions

In order to evaluate the response of safflower (Cartharrus tinectorius L.) to sowing dates in rainfed farming conditions, an experiment was carried out in Khorramabad, Lorestan, during 2004-2006. The experimental design was a split plot based on randomized complete block design with 3 replications. Main plot were consisted of 2 cultivars (local Esfahan, and Zarghan) and 8 sowing dates (5 November, 25 November, 15 December, 4 January, 24 January, 13 February, 5 March, 25 March) were allocated to subplots. Combined analysis of variance results showed that Esfahan local cultivar with seed yield of 1834 kg/ha, harvest index of 27.7%, 1000 seeds weight of 40.3 g, 16.9 capitoles per plant, 30.4 seeds per capitole, oil percent of 28.9, and oil yield of 532.3 kg/ha had a significant superiority over Zarghan cultivar. Sowing date had a significant effect on all studied traits with the exception of seed oil content. The highest level of seed yield, biological yield, harvest index, heads per plant, seeds per head, 1000 seeds weight, and oil yield was achieved in the November fifth, sowing date, and the least of this traits were obtained in 25 March sowing date. Autumn sowing dates had superiority over spring sowing dates for yield and other studied traits, and the optimum sowing date for autumn and spring cultivation were 5 November, and 5 March, respectively.