Creation of a watermelon haploid inducer line via ClDMP3-mediated single fertilization of the central cell

Abstract

The use of doubled haploids is one of the most efficient breeding methods in modern agriculture. Irradiation of pollen grains has been shown to induce haploids in cucurbit crops, possibly because it causes preferential fertilization of the central cell over the egg cell. Disruption of the DMP gene is known to induce single fertilization of the central cell, which can lead to the formation of haploids. In the present study, a detailed method of creating a watermelon haploid inducer line via ClDMP3 mutation is described. The cldmp3 mutant induced haploids in multiple watermelon genotypes at rates of up to 1.12%. These haploids were confirmed via fluorescent markers, flow cytometry, molecular markers, and immuno-staining. The haploid inducer created by this method has the potential to greatly advance watermelon breeding in the future.

Acknowledgements

This work was supported by the National Youth Talent Program (A279021801), Earmarked Fund for China Agriculture Research System (CARS-25), Key-Area R&D Program of Guangdong Province (2022B0202060001), Key R&D Program of Shaanxi province (2023-YBNY-008), the Natural Science Foundation of Shaanxi Province (2022JM-112) and the Science and Technology Innovation Team of Shaanxi (2021TD-32). We would like to thank A&L Scientific Editing (www.alpublish.com) for its linguistic assistance during the preparation of this manuscript.

Author’s contributions

L.Y. conceived the study and designed the experimental scheme. X.E.C., Y.X.L., G.L.A. and J.F.C. executed the experiments. S.J.T., J.F.W., M.L., D.L.G., Z.H.Z. and X.J.Z. provided technical suggestions. L.Y. and X.E.C. wrote the manuscript.

Data availability statement

All data generated in this study are presented in the paper. Additional data related to this paper may be requested from the authors.

Conflict of interests

The authors declare no competing interests.

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