A simple and efficient gene functional analysis method for studying the growth and development of peach seedlings

Abstract

Stable genetic transformation of peach [ Prunus persica (L.) Batsch] still faces many technical challenges, and existing transient expression methods are limited by tissue type or developmental stage, making it difficult to conduct functional analysis of genes regulating shoot growth. To overcome this dilemma, we developed a three-step method for efficient analysis of gene functions during peach seedling growth and development. This method resulted in transformation frequencies ranging from 48 to 87%, depending on the gene. From transformation of germinating seeds to phenotyping of young saplings took just 1.5 months and can be carried out any time of year. To test the applicability of this method, the function of three tree architecture-related genes, namely PpPDS, PpMAX4, and PpWEEP, and two lateral root-related genes, PpIAA14-1 and − 2, were confirmed. Since functional redundancy can challenge gene functional analyses, tests were undertaken with the growth-repressor DELLA, which has three homologous genes, PpDGYLA ( DG ), PpDELLA1 ( D1 ), and − 2 ( D2 ), in peach that are functionally redundant. Silencing using a triple-target vector (TRV2- DG - D1 - D2 ) resulted in transgenic plants taller than those carrying just TRV2- DG or TRV2. Simultaneously silencing the three DELLA genes also attenuated the stature of two dwarf genotypes, ‘FHSXT’ and ‘HSX’, which normally accumulate DELLA proteins. Our study provides a method for the functional analysis of genes in peach and can be used for the study of root, stem, and leaf development. We believe this method can be replicated in other woody plants.

Acknowledgements

The work was conducted at the Henan Provincial Key Laboratory of Fruit and Cucurbit Biology, the International Joint Laboratory of Henan Horticultural Crop Biology, Henan Engineering and Technology Center for Peach Germplasm Innovation and Utilization, and supported by the Joint Funds of the National Natural Science Foundation of China (U1804114), the National Key Research and Development Program of China (2019YFD1000104), and the Modern Agricultural Industry Technology Project of Henan Province (HARS-22-09-G1).

Author contributions

L.Z., Y.S., and X.H. performed the experimental work and generated the data; J.F. and J.C. conceived and designed the experiments; L.G., X.Z., and B.T. analysed the data; W.W., B.T., Z.L., and X.Y. prepared materials; H.Z., X.W., and X.L. provided resources. J.C. and J.F. wrote the paper. All authors read and approved the final manuscript.

Data availability statement

All relevant data are included in the article and its supporting materials.

Conflict of interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary informations

Supplementary data is available at Horticulture Research online.

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