Study of Relationship Between Yield and Yield Components in Tobacco Genotype Using Path Analysis Method

In order to investigat e of Tobacco germplasm genetic diversity، 49 genotypes were grown in Tobacco Research Institute (Rasht، IRAN) as a simple lattice design 7×7 with 2 replications and 12 treatments were evaluated as well. Correlation analysis to studied traits showed that Fresh leaf yield with leaf number، leaf length، leaf width، leaf area index، plant height، flowering period and days to flowering had positive and high correlation. Also correlation of dried leaf yield with other traits except flowering period was positive. Stepwise regression analysis showed that only two traits: fresh leaf yield (X1) and leaf numbers (X2) were affected on dried leaf yield significantly. Thus، direct effect of these two traits on dried yield were calculated 0. 5 and 0. 47 respectively by Path analysis. The stepwise regression analysis showed that plant height (X1) and leaf area index (X2) had highly significant effect on fresh leaf yield and they were considered as second step of dry leaf yield.