68 
6, 14, 15 
Pp YY bb 
7 
pp yy Bb 
8 
pp Yy Bb 
9, 17, 18 
pp yy bb 
10, 13 
PP yy Bb 
11 
PP yy Bb 
12 
PP yy bb 
These plants represented all phenotypes ex- 
cept one, bronze with purpleback, P Y B. 
SUMMARY AND CONCLUSIONS 
The mode of inheritance of flower color in 
Asystasia gangetica Linn, was determined. Yel- 
low flower color is dependent on gene Y 
which is dominant to white. 
Two patterns of anthocyanin pigmentation 
exist, one in which the inner epidermis of the 
limb is colored, and the other in which the 
outer epidermis of the limb and the back of 
the tube are colored. The gene P produces 
the former pattern while the gene B is re- 
sponsible for the latter. Gene P was deter- 
mined to be additive in its effect; PP results 
in dark forms while Pp in light forms. 
Genes P, Y , and B are inherited independ- 
ently of one another. The dihybrid F 2 segre- 
gants fit the 93:3:1 ratios if the pale and dark 
purple forms are classed together. Where pur- 
ple anthocyanin occurs together with yellow 
pigment, a bronzy color results. With the 
three genes for flower colors operating, eight 
basic phenotypes are obtainable. Since white 
flower color is due to the recessive condition 
of all three genes, pp , yy, bb , the limited num- 
ber of such forms appearing in open pollinated 
progenies is explained. 
PACIFIC SCIENCE, Vol. IX, January, 1955 
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