Response of bread wheat genotypes with different flowering habits to sowing date in Isfahan

In order to assess the impact of different sowing dates on yield and yield components of wheat genotypes with different growth habits، a two years study (2007-2009) using a split plot in randomized complete block design with three replications was conducted in Kabootarabad Agricultural Research Station of Isfahan. Three sowing dates of 12 Oct.، 1 Nov.، and 21 Nov. were main plots and 15 genotypes of wheat were subplots. The average grain yield in three planting dates was 8495، 9156 and 6749 kg ha-1، respectively. At all planting dates، the maximum and minimum grain yield belonged to spring and winter types and the grain yield of winter، facultative and spring groups were 7519، 8267 and 8614 kg ha-1، respectively. At 1 Nov. five spring genotypes M-81-13، Bahar، Pishtaz، Kavir and Marvdasht and facultative cultivar Alvand produced the highest grain yield by an average of 10433، 10146، 10040، 9843، 9822 and 9813 kg/ha and therefore can be recommended for planting in temperate regions of the province. Spikes per m2 and grain weight were the most important yield components that were reduced in response to late planting. Based on the results، 1 Nov. can be recommended as the best planting date for the region.