Inheritance of traits related to yield and fatty acid profile of winter squash seed oil

Abstract

The objective of this study was to determine the inheritance of traits related to seed oil yield and fatty acid profile components and to estimate the genetic relationships between these traits in Cucurbita moschata D. This study assessed six generations derived from crosses between parents with contrasting traits under study. F1 plants were obtained from the crossing between BGH 7319 (P1) and ‘Tronco Verde’ (P2), which were subsequently self-fertilized to obtain the F2 generation. F1 plants were also backcrossed with the P1 and P2 parents to obtain the BC1 and BC2 generations, respectively. In general, additive effects were predominant for most of the traits, and thus, the development of inbred lines is the recommended strategy for genetic improvement of these traits. Dominance effects were significant even under low expression. This demonstrates that the performance of progeny tests throughout the selfing generations will enable the distinction between genotypes, thus providing greater efficiency in selection and, consequently, greater genetic gains. In addition, overdominance was observed in oil content; therefore, the development of hybrids with genotypes causing high oil content is attainable. In general, the estimates of genetic correlations had a high magnitude and were favorable to the increase in functional oil productivity, associated with better quality of fatty acid profiles. Recurrent intrapopulation selection aimed at the development of open-pollinated varieties with high productivity, associated with greater stability of the functional oil in C. moschata, may be useful.