Abstract

Jatropha curcas L. (JLC) is a perennial shrub, originating in Central and South America and widely distributed in the tropical regions of the world. It is important in the bioenergy industries due to the characteristics of its oil which can be transformed into high quality biofuel for the substitution of diesel and jet fuel. The native gene, female only flower (FOF), is a desirable trait in the production of hybrid seed of J. curcas. L. In this study, inbreeding was induced in eight accessions from wild, S₁, S₂ to S₃ endogamy level, and two wild accessions naturally expressing the FOF trait were used as females to cross with male accessions (FM) in order to estimate segregation. The Chi-Square test was used to determine if the FOF trait follows a Mendelian inheritance. Results strongly support the assumption that FOF trait follows a recessive monogenic Mendelian inheritance pattern since, in the inbreeding process of the trait, it segregated a phenotypic frequency of 3:1 (FM:FOF) and in crosses, a frequency of 1:1 (FM:FOF) was segregated. This study potentially contributes to furthering the commercial production of JLC hybrid seed, given that the plants with FOF trait can be used as female parents to be naturally pollinated in isolated plots, thereby reducing labor and cost.

Key words: Floral biology, heredity, inbreeding, Jatropha curcas, native gene.