evaluation of yield, rate and effective grain filling period of four barley (hordeum vulgaris l.) cultivars in different planting dates

in other to evaluate grain yield, rate and effective grain filling period of four barley (hordeum vulgaris l.) cultivars in different planting dates, a factorial experiment based on a randomized complete block design was conducted in the islamic azad university of ardabil research station in 2009. the treatments applied were: three levels of different planting dates (september, 23; october, 16 and october, 22) with four barley cultivars (lesivei, sahandi, makouee and bahman). the results showed that planting dates had significant effects on yield, rate and effective grain filling period of barley (hordeum vulgaris l.) cultivars. a linear model was used to investigate the grain filling parameters indicating the significance of maximum kernel weight (0.056 mg) and effective grain filling period (25.5 days) which was obtained in 23 september. the results of means' comparisons showed that maximum of kernel weight (0.049 mg) and effective grain filling period (25.5 days) were obtained in lesivei cultivar ×  september, 23; and minimum of it (0.028 mg and 21.7 days) was seen in sahand cultivar×  october, 22, respectively. grain yield was significantly affected by cultivar treatment, different planting date and interaction of cultivars × planting date. it was also found that maximum grain yield (2.022 t/ha) was obtained at september, 23 with lesivei cultivar and a minimum of 1.490 t/ha was obtained for sahand cultivar at october, 22 planting date. thus, it can be suggested that in order to increase grain yield and grain filling period, lesivei cultivar should be planted around september 23 under ardabil regions' conditions.