台農82號誘變系與台灣栽培稻抗稻熱病基因座之定位

Mapping of resistance genes to rice blast in Tainung 82 mutant lines and Taiwan’s rice cultivars

施昱全(Yu-Cyuan Shih)

指導教授 ： 鍾嘉綾

國立臺灣大學/生物資源暨農學院/植物病理與微生物學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201703478

摘要

稻熱病普遍發生於全球各水稻產區，可嚴重危害水稻生產，而種植抗病品種被認為是最經濟、有效且對環境友善的防治方式。本研究以誘變育種法結合次世代定序技術開拓新抗性種原，並以連鎖法分析臺灣既有水稻品種所含抗病基因，以提供新抗性基因導入、抗病品種使用與輪替之必要資訊。台農82號經連續5代之疊氮化鈉誘變處理及病圃篩選後，獲得44個具優異抗性之誘變系；11個「台農82 x 台農82誘變系」雜交組合之F2族群 (共6300植株) 於105年二期作在嘉義農業試驗分所稻熱病圃完成抗性檢定，其中台農82號 x WM1363 之F2族群中，抗感病個體比例為408:162，符合單基因遺傳分離率3:1，以MutMap-plus analysis探討該F2族群中極抗個體與台農82號親本間具差異之SNP位點，發現有4個SNPs可能是影響抗性之關鍵突變位點，分別位於一個NBS-LRR protein (Os04g0122000) 及三個serine/threonine kinase-related receptors (Os04g0103500、Os04g0103700和Os12g0114100) 基因區域內。台稉8號、台稉14號及台東30號為國內種植面積廣且在不同地區均呈現中等抗性的栽培稻品種，而Pi2/9、Pik與Pita/Pita-2基因座上的抗性等位基因對臺灣稻熱病菌群普遍較具抗性；本研究將三個栽培品種與感病品系LTH雜交建立F2族群，透過人工接種評估抗性表現，及新設計多型性分子標誌進行基因型分析，確認台稉14號帶有Piz-t，台稉8號帶有與Pik僅一個氨基酸差異之抗性等位基因，而台東30號之抗性則來自Pita/Pita-2基因座上、不同於Pita之抗性基因，相關成果可供稻熱病防治及育種參考。

關鍵字

稻熱病 ； 抗病基因座 ； 台農82號 ； 誘變品系 ； 台灣栽培稻

並列摘要

Rice blast disease can seriously damage rice production worldwide, and the use of resistance varieties has been considered the most economically, effective and ecofriendly method for blast control. To provide information needed for introgression of resistance genes, variety deployment and rotation, this study focuses on (1) exploring novel resistance genes/loci by mutation breeding combined with next-generation sequencing technique and (2) identifying the resistance genes/loci in Taiwan high-quality rice varieties through linkage analysis. After 5 generations of NaN3-induced mutation and resistance screening in rice blast nursery, we got 44 NaN3-induced Tainung 82 (TNG82) mutant lines with good resistance. We generated 11 F2 populations from the crosses of “TNG82 x 11 TNG82 mutant lines”, and totally 6300 F2 individuals were evaluated in the upland blast nursery at Chiayi Agricultural Experiment Branch in the second cropping season of 2016. The ratio of resistant to susceptible F2 individuals of “TNG82 x WM1363” is 408: 162, which fits the 3:1 ratio under single-gene inheritance pattern. To identify novel genes associated with resistance, MutMap-plus analysis strategy was applied to compare the SNPs between a pooled sample composed of the most resistant F2 individuals and the parental line TNG82. Four SNPs were identified as the most likely causal mutations: one locates in the gene encoding NBS-LRR protein (Os04g0122000) and three locate in the genes encoding serine/threonine kinase-related receptors (Os04g0103500, Os04g0103700, Os12g0114100). Taikeng 8 (TK8), Taikeng 14 (TK14), and Taitung 30 (TT30) are three widely cultivated Taiwan rice cultivars which have exhibited moderate to high resistance in different rice-growing regions around Taiwan. Previous artificial inoculations and field trials showed that resistance alleles at four loci (Pi2/9, Pik, and Pita/Pita-2) are generally effective against more Taiwanese isolates of rice blast pathogen. F2 populations from the four Taiwan high-quality rice varieties crossed with a susceptible line LTH were developed and evaluated for resistance by artificial inoculation. Linkage analyses based on newly designed polymorphic makers targeting the four R loci revealed that TK14 carries Piz-t, TK8 carries a resistance allele with only one amino acid difference from Pik, and the resistance of TT30 likely come from resistance gene(s) other than Pita at the Pita/Pita-2 locus. The results can serve as useful references for disease control and resistance breeding in the future.

並列關鍵字

rice blast ； resistance loci ； Tainung 82 ； mutant lines ； Taiwan’s rice cultivars

參考文獻

林富雄。2006。水稻產量、品質及抗病蟲害育種的回顧及展望。作物、環境與生物資訊 3：285-296。

張瑞炘、楊嘉凌、許志聖。2011。水稻抗白葉枯病之分子標誌輔助育種。臺中區農業改良場研究彙報 110：55-70。

張義璋。2001。水稻稻熱病防治手冊。行政院農業委員會台中農業試驗所。

陳韋綸、沈偉強、張芳瑜、張為斌、余宗學、賴明信、廖睿瑜、吳志文、鍾嘉綾。 2015。應用於臺灣良質米品種改良之抗稻熱病基因座分析與分子標誌開發。 植物病理學會刊 24：225-240。

陳隆澤、陳一心、程永雄。2004。1990至2002年臺灣水稻品種 (系) 抗稻熱病檢定。中華農業研究 53：269-283。