Genetic Research on Fruit Color Traits of the Bitter Gourd (Momordica charantia L.)

Abstract

The objective of this study was to determine the genetic model of fruit color in the bitter gourd (Momordica charantia L.). Six generations (P₁, P₂, F₁, F₂, BCP₁, and BCP₂) in the hybrid set “MS 41 × MS 47” were used to estimate the genetic effects via generation mean analysis (GMA). The fruit color of the F₁ population was green implying the green color was dominant over the white color. The fruit color of the F₂ population showed a continuous distribution from white to dark green indicating this trait was controlled by quantitative genes. Genetic analyses using the Royal Horticultural Society scoring system (RHS score) fitted the three parameters model (χ²₃ = 1.59, P = 0.6607) and showed significant to highly significant additive and dominance effects, respectively. The GMA results of the six parameters model revealed a significant additive effect on chlorophyll b concentration. Chlorophyll a and total chlorophyll concentrations were nonsignificant in all parameters. The magnitudes of additive and additive × additive gene effects were larger than those of the dominance and dominance × dominance gene effects, which revealed that additive genes were more important in the contribution to chlorophyll concentrations. Broad-sense heritability estimates for color traits were 0.39, 0.611, 0.470, and 0.460 for concentrations of chlorophyll a, chlorophyll b, total chlorophyll, and RHS score, respectively. In contrast to previous findings, with the GMA analysis we believe that the genetic model of fruit color in bitter gourd is clearly a quantitative model.