An Overview of Doubled Haploid Plant Production in Cucurbita Species

Abstract

F1 cultivars are currently used in vegetable production because of their many superior agronomic advantages (high yield and quality, resistance/tolerance to biotic and/or abiotic stress factors, wide adaptability, etc.). It is not possible to produce hybrid vegetables without homozygous pure parental lines with defined traits and high combining ability. However, the production of homozygous pure parents needs a long time, great efforts, and high production cost. Moreover obtaining an F1 hybrid variety takes 8-10 years with traditional breeding methods, especially in a highly open-pollinated species such as Cucurbita spp. Doubled haploid (DH) technologies (parthenogenesis, androgenesis, and gynogenesis), called biotechnological breeding methods, have become an alternative to classical breeding methods and provide to obtain pure lines within 1-2 years by adapting to these technologies in F1 hybrid breeding programs. Although the DH technologies considered a meaningful approach to enhance the production of valuable double haploid plants, the implementation of these techniques needs labor-intensive efforts, high experiences, and advanced technologies. The main objective of this review to provide a summary of DH techniques applied in the Cucurbita species in the current progress.