Reaction of radiation interception, light extinction coefficient, yield and yield components of barley to planting pattern and seeding rate

To study the reaction of radiation interception, light extinction coefficient, yield and yield components of barley (Hordeum Vulgare L.), cultivar Jonoob, to planting pattern and seeding rate, an experiment was carried out in Ramin Agriculture and Natural Resources University of Khuzestan, Ahvaz, Iran, during 2013-14 cropping season. This research was conducted as strip plot in randomized complete block design with three replications. Four planting patterns (flat planting with 17 cm distance between rows, flat planting with 25 cm distance between rows, two rows on ridges with 50 cm wide and three rows on ridges with 50 cm wide) as first factor and four seeding rates (200, 300, 400 and 500 seeds per m2) as second factor were considered. Results showed that the effect of treatments on light extinction coefficient were not significant. Flat planting with 17 cm row distance, led to increase in radiation received, better distribution of light and significant increase of grain and biological yield, because maximum spike number per m2 and leaf area index. However, the maximum 1000 grain weight was obtained from three-rows on ridge. Spike number per m2 and chlorophyll index were decreased by increasing the seeding rate, but grain yield, spikelet number per spike and grain number per spike were decreased. The maximum grain yield (5072.1 kg.ha-1) was obtained from flat planting with 17 cm row distance and most appropriate seeding rate to obtain mazimum grain yield was 200 seeds per m2.