Cai Lichun, Adelberg Jeffrey, Naylor-Adelberg Jacqueline, Schnabel Guido, Calle Alejandro, Li Zhigang, Reighard Gregory, Gasic Ksenija, Saski Christopher A
Department of Plant and Environmental Sciences, Clemson University, Clemson, SC, United States.
Front Plant Sci. 2023 Jun 2;14:1181153. doi: 10.3389/fpls.2023.1181153. eCollection 2023.
root rot (ARR) poses a significant threat to the long-term productivity of stone-fruit and nut crops in the predominant production area of the United States. To mitigate this issue, the development of ARR-resistant and horticulturally-acceptable rootstocks is a crucial step towards the maintenance of production sustainability. To date, genetic resistance to ARR has been found in exotic plum germplasm and a peach/plum hybrid rootstock, 'MP-29'. However, the widely-used peach rootstock Guardian® is susceptible to the pathogen. To understand the molecular defense mechanisms involved in ARR resistance in rootstocks, transcriptomic analyses of one susceptible and two resistant spp. were performed using two causal agents of ARR, including and . The results of co-culture experiments revealed that the two resistant genotypes showed different temporal response dynamics and fungus-specific responses, as seen in the genetic response. Gene expression analysis over time indicated an enrichment of defense-related ontologies, including glucosyltransferase activity, monooxygenase activity, glutathione transferase activity, and peroxidase activity. Differential gene expression and co-expression network analysis highlighted key hub genes involved in the sensing and enzymatic degradation of chitin, GSTs, oxidoreductases, transcription factors, and biochemical pathways likely involved in resistance. These data provide valuable resources for the improvement of ARR resistance in rootstocks through breeding.
根腐病（ARR）对美国主要产区的核果类和坚果类作物的长期生产力构成了重大威胁。为缓解这一问题，培育抗ARR且园艺性状优良的砧木是维持生产可持续性的关键一步。迄今为止，已在外来李属种质资源和一种桃/李杂交砧木“MP - 29”中发现了对ARR的遗传抗性。然而，广泛使用的桃砧木Guardian®对该病原菌敏感。为了解砧木中与抗ARR相关的分子防御机制，利用ARR的两种致病因子，包括[具体致病因子1]和[具体致病因子2]，对一种感病和两种抗病[物种名称]进行了转录组分析。共培养实验结果表明，这两种抗性基因型表现出不同的时间响应动态和真菌特异性反应，这与遗传反应一致。随时间进行的基因表达分析表明，与防御相关的本体富集，包括糖基转移酶活性、单加氧酶活性、谷胱甘肽转移酶活性和过氧化物酶活性。差异基因表达和共表达网络分析突出了参与几丁质感知和酶促降解、谷胱甘肽转移酶、氧化还原酶、转录因子以及可能与[抗病性相关的具体名称]抗性相关的生化途径的关键枢纽基因。这些数据为通过育种提高[砧木名称]对ARR的抗性提供了宝贵资源。
