effect of establishment of nursery under plastic cover on yield of some rice cultivars in lordegan region, chahar-mahal bakhtiari province

this experiment was conducted to evaluate the effect of nursery establishment under plastic cover on yield of some rice cultivars at lordegan region in 2007. experimental design was a split plot with a randomized complete block with three replications. four rice cultivars (hashemi, hasani, saleh and native) were seeded at three seedling date (14 april, 5 may and 15 may). two first planting dates was under plastic cover and third planting date was under free plastic cover. results showed that delay in seedling date significantly decreased grain yield, biological yield and harvest index. the maximum grain yield was obtained in hashemi cultivar. interaction between seedling date and cultivar on grain yield were significant. saleh cultivar produced maximum yield at 14 april seedling date and saleh cultivar in 15 may seedling date had minimum grain yield.