Identification and application of a candidate gene AhAftr1 for aflatoxin production resistance in peanut seed (Arachis hypogaea L.)

Bolun Yu; Nian Liu; Li Huang; Huaiyong Luo; Xiaojing Zhou; Yong Lei; Liying Yan; Xin Wang; Weigang Chen; Yanping Kang; Yingbin Ding; Gaorui Jin; Manish K Pandey; Pasupuleti Janila; Hari Kishan Sudini; Rajeev K Varshney; Huifang Jiang; Shengyi Liu; Boshou Liao

doi:10.1016/j.jare.2023.09.014

Identification and application of a candidate gene AhAftr1 for aflatoxin production resistance in peanut seed (Arachis hypogaea L.)

J Adv Res. 2023 Sep 20:S2090-1232(23)00263-1. doi: 10.1016/j.jare.2023.09.014. Online ahead of print.

Authors

Bolun Yu¹, Nian Liu¹, Li Huang¹, Huaiyong Luo¹, Xiaojing Zhou¹, Yong Lei¹, Liying Yan¹, Xin Wang¹, Weigang Chen¹, Yanping Kang¹, Yingbin Ding¹, Gaorui Jin¹, Manish K Pandey², Pasupuleti Janila², Hari Kishan Sudini², Rajeev K Varshney³, Huifang Jiang¹, Shengyi Liu¹, Boshou Liao⁴

Affiliations

¹ Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture Oil Crops Research Institute (OCRI), Chinese Academy of Agricultural Sciences (CAAS), Wuhan, China.
² International Crops Research Institute for the Semi-Aird Tropics (ICRISAT), Hyderabad, Telangana, India.
³ Centre for Crop and Food Innovation, State Agricultural Biotechnology Centre, Food Futures Institute, Murdoch University, Murdoch, Australia.
⁴ Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture Oil Crops Research Institute (OCRI), Chinese Academy of Agricultural Sciences (CAAS), Wuhan, China. Electronic address: lboshou@hotmail.com.

PMID: 37739123
DOI: 10.1016/j.jare.2023.09.014

Abstract

Introduction: Peanut is susceptible to infection of Aspergillus fungi and conducive to aflatoxin contamination, hence developing aflatoxin-resistant variety is highly meaningful. Identifying functional genes or loci conferring aflatoxin resistance and molecular diagnostic marker are crucial for peanut breeding.

Objectives: This work aims to (1) identify candidate gene for aflatoxin production resistance, (2) reveal the related resistance mechanism, and (3) develop diagnostic marker for resistance breeding program.

Methods: Resistance to aflatoxin production in a recombined inbred line (RIL) population derived from a high-yielding variety Xuhua13 crossed with an aflatoxin-resistant genotype Zhonghua 6 was evaluated under artificial inoculation for three consecutive years. Both genetic linkage analysis and QTL-seq were conducted for QTL mapping. The candidate gene was further fine-mapped using a secondary segregation mapping population and validated by transgenic experiments. RNA-Seq analysis among resistant and susceptible RILs was used to reveal the resistance pathway for the candidate genes.

Results: The major effect QTL qAFTRA07.1 for aflatoxin production resistance was mapped to a 1.98 Mbp interval. A gene, AhAftr1 (Arachis hypogaea Aflatoxin resistance 1), was detected structure variation (SV) in leucine rich repeat (LRR) domain of its production, and involved in disease resistance response through the effector-triggered immunity (ETI) pathway. Transgenic plants with overexpression of AhAftr1_(ZH6) exhibited 57.3% aflatoxin reduction compared to that of AhAftr1_(XH13). A molecular diagnostic marker AFTR.Del.A07 was developed based on the SV. Thirty-six lines, with aflatoxin content decrease by over 77.67% compared to the susceptible control Zhonghua12 (ZH12), were identified from a panel of peanut germplasm accessions and breeding lines through using AFTR.Del.A07.

Conclusion: Our findings would provide insights of aflatoxin production resistance mechanisms and laid meaningful foundation for further breeding programs.

Keywords: Aflatoxin production resistance; Diagnositic marker; ETI; NB-LRRs; Peanut.