2012-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/689754摘要：草莓為高經濟及高營養價值之水果，因其簡易且快速繁殖之特性，適合做為薔薇科果樹研究的模式植物。病蟲危害及農藥殘留是臺灣在草莓生產上的主要瓶頸，為克服此一困難，須對草莓 (尤其本土栽培品種) 的抗感病機制有所瞭解。本研究擬以草莓在苗期、果實期危害最普遍且嚴重的炭疽病、灰黴病為模式，詳細探討其抗病機制。為能完整解析草莓的防禦系統，本研究擬運用Illumina次世代定序技術，針對水楊酸及茉莉酸在抗病、感病草莓品系上所誘導之基因表現，以高通量方式進行mRNA-seq whole-transcriptome analysis，以建構抗性相關基因資料庫。對於在抗、感病品系植株上之表現時間、表現量具顯著差異的基因，將針對其中具新穎性、重要性者，進一步探討其在草莓抗hemibiotroph (炭疽病) 及necrotroph (灰黴病) 過程中所扮演的角色。實驗方法包括以quantitative real-time RT-PCR進行發病過程中的基因表現量分析，以及利用tobacco rattle virus (TRV)-based virus induced gene silencing (VIGS) system，將候選基因靜默後，視其對1) 植物巨觀及微觀抗感病性狀及 2) 已知抗病途徑中重要調控基因表現量之影響等，以逐步建立完整的上下游抗病基因網絡。本研究所發現之抗病機制，將可應用於防治技術之開發，相關防禦基因則可作為草莓抗病育種所需之分子標誌，期盼有助解決草莓之嚴重病害問題，並作為其他薔薇科經濟果樹之抗病研究參考。<br> Abstract: Cultivated strawberry (Fragaria x ananasa; mostly octaploids) is an economically important fruit crop with high nutritional value. The propagation characteristics of strawberry (relatively simpler and faster) makes it a potential model system for Rosaceae plants. Pest damage and pesticide residue problem have always been major threats to strawberry cultivation in Taiwan. These problems in strawberry production may be mitigated through the use of novel non-pesticide control strategies. With the aim to tackle agricultural and food safety issues, we propose to conduct an in-depth study for understanding the defense mechanisms in strawberry cultivar(s) in Taiwan. Two most serious strawberry diseases at seedling and fruiting stages – anthracnose (caused by Colletotrichum gloeosporioides) and gray mold (caused by Botrytis cinerea), will be focused in this study. In order to get an overall picture of defense response pathway, we plan to use the Illumina next generation sequencing technology for high-throughput identification of genes up- and down-regulated by salicylic acid (SA) and jasmonate acid (JA). Using the whole-genome sequence of a diploid strawberry (Fragiria vesca) as a reference, the mRNA-seq transcriptome analysis will allow us to establish a database of defense-related genes in strawberry. Among the genes differentially expressed in the resistant versus susceptible cultivars, a set of candidate genes of our interest will be further characterized. Specifically, the expression levels of selected candidate genes at different time points during C. gloeosporioides (hemibiotrophic) and B. cinerea (necrotrophic) pathogenesis will be analyzed using real-time quantitative RT-PCR. The roles of (a few key) candidate genes will also be investigated in the tobacco rattle virus (TRV)-based virus induced gene silencing (VIGS) system, by evaluating the influence of gene silencing on 1) macroscopic/microscopic resistance phenotypes and 2) the expression levels of known regulatory genes in the SA- and JA-induced pathways. The upstream/downstream relations between each candidate gene and the known regulatory genes in the defense network can be preliminarily delineated. Uncovering the mechanisms underlying strawberry resistance against hemibiotrophic and necrotrophic pathogens is expected to facilitate the development of new approaches for integrated disease management. The defense-related genes identified in this study can potentially be used as selection markers in strawberry resistance breeding programs. Our understanding of disease resistance in strawberry will benefit the resistance research in other important Rosaceae plants.Fragaria x ananasa炭疽病Colletotrichum gloeosporioides灰黴病Botrytis cinerea水楊酸茉莉酸防禦途徑次世代定序Fragaria x ananasaAnthracnoseColletotrichum gloeosporioidesGray moldBotrytis cinereaSalicylic acidJasmonic aciddefense pathwaynext-generation sequencing