INHERITANCE OF PLEATED FOLIAGE AND RED FLOWER IN IXORA

Ixora, a popular woody bedding plant, has many flower colors. Besides its bright flower color, there is another interesting mutant trait of pleated leaf. To conduct a successful improvement program to create a hybrid of commercial interest, a breeder ought to have inheritance knowledge of the trait of concern. A hybrid between a red flower with pleated leaf Ixora coccinea ‘Bangkok Bow’, a mutant, and a yellow flower with normal leaf Ixora chinensis ‘Singapore Yellow’ was made. Flowers of all progeny of the interspecific hybrid had orangish red color, with co-existence of red and yellow pigments. However, the population segregated into two leaf forms, suggesting a qualitative trait. The test cross ratio of 1:1 for normal leaf-to-pleated leaf was confirmed by Chi-square test. Thus, the mutant leaf form is a dominant trait.