اثر تنش كم آبياري و تراكم گياهي بر خصوصيات مورفولوژيك و عملكرد دانه در يك هيبريد پاكوتاه آفتابگردان (CMS26 * R103) در كشت دوم

Effect of limited irrigation and plant density on morphological characteristics and grain yield in a dwarf sunflower hyhrid (CMS26 x RI03) as second crop

In order 10 study effects of limited irrigation and plant density on morphological characteristics and seed yield of a dwarf sunflower hybrid CMS26 x RI 03. a field experiment was conducted in a spilt plot arrangement using randomized complete block design with three replications in Seed and Plant Improvement Institute Karaj in 2005 cropping season. Limited irrigation levels included: irrigation after 50. 100. 150 and 200 millimeter evaporation from class A pan and plant density levels were 6. 8, 10 and 12 plant m-2 that were assigned to main and sub plots. respectively. Limited irrigation had significant effect on plant height. head diameter, seed yield, productivity index. seed oil content and oil seed yield, but there was no significant effect on leaf number. Plant density affected on all characteristics. except of plant height. seed oil content and productivity index. The highest seed yield of 2726 kg.haʹ was obtained from irrigation after 50 mm evaporation from class A pan. The highest seed yields under different irrigation levels were also obtained from 12 plant mʹ. Results indicated that under irrigation after 50, 100 and 150 millimeter evaporation from class A pan, maximum seed yield was obtained from 12 plant m"2. however in irrigation after 200 millimeter evaporation from class A pan and 12 plant m-~ yield increase was not significant. due mainly to stress severity.