The cytological mechanism of the peach haploid producing triploid offspring

Abstract

Peach is one of the most economically valuable fruit trees. Haploid peach trees occur spontaneously at very low frequencies and they are usually highly sterile. Therefore, the haploid with partial fertility is an extremely rare germplasm, which is highly valuable to genetic research and breeding programs. In this study, we investigated the cytological mechanism underlying the fertility of a peach haploid mutant ‘9-D’ derived from a spontaneous mutation. Cytologic evaluation and flow cytometry analysis demonstrated that ‘9-D’ is a pure haploid. Scanning electron microscope analysis revealed a considerable proportion of abnormal pollen grains in ‘9-D’. Pollen viability assay by Alexander staining showed that 50.4% of pollen grains from ‘9-D’ were viable. However, the pollen germination assay showed that only 7.6% of the pollen grains could germinate normally. Investigation of the chromosomal behavior of pollen mother cells at different stages of meiosis showed that pollen mother cells of ‘9-D’ lacked the process between anaphase I and prophase II of meiosis. Various types of sporophyte morphology were observed in haploid pollen mother cells at the tetrad stage. Measurement of the diameter of pollen grains indicated the presence of pollen with 2x ploidy in ‘9-D’. The offspring of ‘9-D’ were predominantly triploid or triploid aneuploid. The triploid offspring were more likely derived from the 2x male gametophyte combined with the haploid female gametophyte, which may explain the reason why ‘9-D’ has fertility. This study not only expands our understanding of haploid fertility mechanisms, but is also useful for ploid breeding programs in peach.

Acknowledgments

We are grateful to Weichao Fang (Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences) and Zhixiang Cai (Institute of Pomology, Jiangsu Academy of Agricultural Sciences), who provided the partial pictures of peaches. This research was supported by the earmarked fund for China Agriculture Research System of Peach (CARS-30), National Natural Science Foundation of China (31301734), and Beijing Academy of Agriculture and Forestry Sciences Innovation Capability Construction Special Project (KJCX20230118).

Author contributions

XL analyzed the data and prepared the manuscript. DDL and YZ analyzed the data. XZ and SDW. performed experiments. JBZ and JYG performed the collection and processing of samples. QJ and RF conceived and led the research and coordinated the experiments. All authors read and approved the manuscript.

Data availability

The data are presented within the paper. All authors consent to publication of these data.

Conflict of interests

The authors declare that they have no conflicts of interest.

Supplementary data

Supplementary data is available at Horticulture Research online.

References

[1] Chen XS, Wang N, Peng FT. et al. Advances in quality and maturity breeding of important deciduous fruit trees in China. Acta Hortic Sin. 2024;51:8-26

[2] Li Y, Wang LR. Genetic resources, breeding programs in China, and gene mining of peach: a review. Hortic Plant J. 2020;6:205-15

[3] Monet R, Bassi D. Classical genetics and breeding. In: LayneD, BassiD, The Peach: UK,eds. Botany, Production and Usesanonymous. CABI: Wallingford, 2008,61-84

[4] Li YH, Zhao F, Zhang SS. et al. Research Progress in ploidy breeding of drupe fruit trees. Tibet Journal of Agricultural Sciences. 2021;43:93-5

[5] Wang SD, Ren F, Zhao JB. et al. Research progress on peach ploidy breeding. Northern Horticulture. 2020;16:126-32

[6] Toyama TK. Haploidy in peach. HortScience. 1974;9:187-8

[7] Pooler MR, Scorza R. Aberrant transmission of RAPD markers in haploids, doubled haploids and F 1 hybrids of peach: observa-tions and speculation on causes. Sci Hortic. 1995;64:233-41

[8] Wang BS, Liu XP, Lian Y. et al. Research progress on hap-loid breeding technology. Journal of Northern Agriculture. 2018; 46:44-9

[9] Ma X, Shen SX, Lian Y. et al. Progress of anther and isolated microspore culture techniques of eggplant. Journal of Changjiang Vegetables. 2006;07:39-41

[10] Hesse CO. Monoploid peaches, Prunus persica batch. Description and meiotic analysis. J Amer Soc Hort Sci. 1971;96:326-30

[11] Hao XF, Zhao S, Chen GJ. et al. Cytological investigation on microsporogenesis of geneticmale sterility of hot pepper. Guang-dong Agricultural Sciences. 2011;21:54-6

[12] Yuan J, Shi G, Yang Y. et al. Non-homologous chromosome pairing during meiosis in haploid Brassica rapa. Plant Cell Rep. 2021;40:2421-34

[13] Zhang CX, Ming J, Liu C. et al. Observation and analysis of abnormal meiotic phenomena of lily pollen mother cells. Bulletin Of Biology. 2010;45:45-47+42

[14] Zhu HJ, Cui QX, Cheng HL. et al. Observation of male gamete development and fertility analysis of haploid eggplant. South China Agriculture. 2021;15:6-12

[15] Cifuentes M, Rivard M, Pereira L. et al. Haploid meiosis in Arabidopsis: double-strand breaks are formed and repaired but without synapsis and crossovers. PLoS One. 2013;8:e72431

[16] Dewitte A, Van Laere K, Van Huylenbroeck J. Use of 2n gametes in plant breeding. Plant Breed. 2012;59-86

[17] Kreiner JM, Kron P, Husband BC. Evolutionary dynamics of unre-duced gametes. Trends Genet. 2017;33:583-93

[18] Mason AS, Pires JC. Unreduced gametes: meiotic mishap or evolutionary mechanism? Trends Genet. 2015;31:5-10

[19] Harlan JR, Dewet JMJ, On Ö. Winge and a prayer: the origins of polyploidy. Bot Rev. 1975;41:361-90

[20] Talluri RS. Gametes with somatic chromosome number and their significance in interspecific hybridization in Fuchsia. Biol Plant. 2011;55:596-600

[21] Zhu S, Song J, Hu Z. et al. Ploidy variation and genetic com-position of open-pollinated triploid citrus progenies. Bot Stud. 2009;50:319-24

[22] De Storme N, Geelen D. Sexual polyploidization in plants -cytological mechanisms and molecular regulation. New Phytol. 2013;198:670-84

[23] Xie KD. Production of Triploids and Genetic Analysis on Unreduced Gamete and Meiotic Inheritance Pattern in Citrus. Wuhan: Huazhong Agricultural University; 2015:

[24] Bielig LM, Mariani A, Berding N. Cytological studies of 2n male gamete formation in sugarcane, Saccharum L. Euphytica. 2003;133:117-24

[25] Werner JE, Peloquin SJ. Significance of allelic diversity and 2n gametes for approaching maximum heterozygosity in 4 x ppota-toes. Euphytica. 1991;58:21-9

[26] Tang XY, Luo ZR, Cai LH. Current researches on unreduced gamate formation and its utilization in plant breeding. J Wuhan Bot Res. 1999;17:1-7

[27] Liao WW, Xing HC, Jie YC. Research progress on plant 2n gamete and lts application. Crop Res. 2011;25:599-603

[28] Orjeda G, Freyre R, Iwanaga M. Production of 2n pollen in diploid Ipomoea trifida, a putative wild ancestor of sweet potato. J Hered. 1990;81:462-7

[29] Li JM. Tutorial on Plant Tissue Culture. 2nd ed. Beijing: China Agricultural University Press; 2002:

[30] Zhao ZL, Zhang SJ, Fan GQ. Research progress of haploid in forest tree. Journal of Henan Agricultural University. 2023;57:179-85

[31] Yang CY, Spielman M, Coles JP. et al. TETRASPORE encodes a kinesin required for male meiotic cytokinesis in Arabidopsis. Plant J. 2003;34:229-40

[32] Zhang ZH. Occurrence and Molecular Markers of Unreduced Pollen In Chinese White Poplar. Beijing: Beijing Forestry University; 2008:

[33] Xiong C. Relationship between genetic variation and drone fecundity. Apiculture of China. 2022;73:49-50

[34] D’Erfurth I, Jolivet S, Froger N. et al.Turning meiosis into mitosis. PLoS Biol. 2009;7:e1000124

[35] D’Erfurth I, Jolivet S, Froger N. et al. Mutations in AtPS 1 (Ara-bidopsis thaliana parallel spindle 1) lead to the production of diploid pollen grains. PLoS Genet. 2008;4:e1000274

[36] Mieulet D, Jolivet S, Rivard M. et al. Turning rice meiosis into mitosis. Cell Res. 2016;26:1242-54

[37] Feng HY, Yao BJ, Chen M. et al. Haploid breeding techniques: research progress. Chin Agric Sci Bull. 2021;37:1-6

[38] Liu Y. Establishment of Suspension Culture System for Haploid Callus of Populus Simonii × P. Nigra and its Genetic Transforma-tion into PsnCYCD1; 1. Harbin: Northeast Forestry University; 2021:

[39] Xie YP, Zheng YH, Guo YD. et al. The first report on one haploid plant in cultivated peanut using anther culture technique. Chi-nese Journal of Oil Crop Sciences. 2022;44:810-7

[40] Jauhar PP. Formation of 2n gametes in durum wheat haploids: sexual polyploidization. Euphytica. 2003;133:81-94

[41] Carputo D. Cytological and breeding behavior of pentaploids derived from 3x × 4x crosses in potato. Theor Appl Genet. 2003;106:883-8

[42] El Mokadem H, Crespel L, Meynet J. et al. The occurrence of 2n-pollen and the origin of sexual polyploids in dihaploid roses (Rosa hybrida L.). Euphytica. 2002a;125:169-77

[43] El Mokadem H, Meynet J, Crespel L. The occurrence of 2n eggs in the dihaploids derived from Rosa hybrida L. Euphytica. 2002b;124:327-32

[44] Rieseberg LH, Willis JH. Plant speciation. Science. 2007;317:910-4

[45] Akutsu M, Kitamura S, Toda R. et al. Production of 2n pollen of Asiatic hybrid lilies by nitrous oxide treatment. Euphytica. 2007;155:143-52

[46] Okazaki K, Kurimoto K, Miyajima I. et al. Induction of 2n pollen by arresting the meiotic process in tulips with nitrous oxide gas. Euphytica. 2005;143:101-14

[47] Verde I, Abbott AG, Scalabrin S. et al. The high-quality draft genome of peach (Prunus persica) identifies unique patterns of genetic diversity, domestication and genome evolution. Nat Genet. 2013;45:487-94

[48] Zhebentyayeva TN, Swire-Clark G, Georgi LL. et al. Aframework physical map for peach, a model Rosaceae species. Tree Genet Genomes. 2008;4:745-56

[49] Alexander MP. Differential staining of aborted and nonaborted pollen. Stain Technol. 1969;44:117-22