Songklanakarin Journal of Science and Technology (SJST) (Nov 2004)
Inheritance and yield components in F3 families of groundnut
Abstract
Inheritance study of groundnut indicated that a single dominant gene governed the flower with red stripe on standard. All F1 plants had red stripe on standard. The segregation of F3:2 families (derived from individual F2 plants) showed 1:2:1 expected ratio (χ2 = 0.659) of 1 non-segregating (plants with red stripe on standard) to 2 segregating (plants with red stripe on standard and plants with no red stripe on standard) to 1 non-segregating (plant with no red stripe on standard). When the F3 groundnut families which had plants with red stripe on standard were combined, the segregation ratio was not different from the 3:1 Mendelian ratio (χ2 = 0.073). The symbols for standard flower trait were designated St for dominant trait and st for recessive trait. For peg's color characteristic, the plants with red stripe on standard flower had purple peg. It is possible that the red stripe on standard flower gene had a pleiotropic effect on peg color or this may indicate linked genes. For characters of pod, the F1 showed moderately reticulate pods.The segregation of F3:2 families showed also a 1:2:1 expected ratio (χ2 = 0.067) giving 1 non-segregating (plants with reticulate pod) to 2 segregating (plants with reticulate pod and plants with smooth pod) to 1 non-segregating (plants with smooth pod). When the F3 groundnut families which had plants with reticulate pod were combined, the segregation ratio was not different from the 3:1 Mendelian ratio (χ2 = 0.065). The results indicated that pod characters were governed by a single gene. The symbols of pod character were designated Re for dominant gene and re for recessive gene. For yield components study, the F3 generation had lower yield than their parents did but some of them had similar yield with their parents. Yield components were highly correlated with each other. In addition, yield components of F3 families were also correlated with their leaf characters. The plants with larger leaf had bigger pods, more prolific pods, and heavier seeds.
