Evaluation of Source and Sink relationship in two sunflower hybrids

Study of sink-source relation has a high value on phloem loading by sucrose and show that which of the source production capacity or sink acceptance capacity has the higher effect on yield. Then a RCBD base on factorial experiment with two sunflower hybrids (Azargol and Alstar) and four seed elimination (without elimination, one third of anthodium lateral seeds, one third of anthodium middle seeds, and one third of anthodium central seeds) were conducted with three replications during 2004 in Tabriz. Seed elimination was done after full pollination. Results showed that there were significant differences between two hybrids in all characters, except 1000 kernel weight and seed thickness. 1000 kernel weight and seed dimensions increased by seed elimination but kernel/grain ratio decreased. Azargol and Alstar shoved 3.9 % and 6.9 % increasing in 1000 kernel weight respectively. 1000 kernel weight in control was 75.43 grams and in one third of anthodium lateral seeds, one third of anthodium middle seeds and one third of anthodium central seed were 81.37, 78.83 and 78.21 gr, respectively. Increasing 1000 kernel weight in elimination levels in related to control showed the source limitation of these hybrids and there was higher source limitation in Alstar than Azargol.