Application of Simplified Triple Test Cross and Combining Ability Analysis to Determine the Gene Action in Safflower

 P.B. Ghorpade and M. R. Wandhare

 Abstract

Highly selected lines of safflower (Carthamus tinctorius L.) were investigated to estimate gene action by using the simplified triple test cross and the line x tester analysis approach. The simplified triple test cross and line x tester approaches were equally effective in determining the additive component of genetic variance. The estimates of dominance components obtained in the presence of epistatic interaction, were biased to a greater extent in the line x tester approach than in the simplified triple test cross approach. The dominance component (H_R) estimated from the line x tester analysis was twice that of the dominance component (H₁) estimated from the simplified triple test cross analysis. The simplified triple test cross analysis has been indicated to be a more useful technique for the study of genetic architecture of economically important characters.

 Key words: Carthamus tinctorius L., gene action.