以分子輔助選種導入hd1、Hd6和ehd1抽穗期基因至水稻越光品種

Introgression of Three Heading Date Genes, hd1, Hd6, and ehd1, to Oryza sativa L. japonica cv. Koshihikari by Marker-Assisted Selection

陳正昇(Cheng-Sheng Chen)

指導教授 ： 林彥蓉

國立臺灣大學/生物資源暨農學院/農藝學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.03063

摘要

水稻栽培在不同地理位置與季節中，會有不同的抽穗期而影響水稻營養生長期，過短的營養生長期會造成稻米產量與品質的下降。在日本，越光具有良好的品質與產量，但種植在台灣時，會因為對光週期敏感而提早抽穗，降低產量與品質。台農67號為台灣本地品種，對於光週期不敏感。分析已選殖的六個抽穗期基因，發現越光與台農67號於三個抽穗期基因Hd1、Hd6與Ehd1存在序列與功能上的差異。本試驗目的即利用分子標幟輔助選種的方式，將此台農67號三個基因導入越光中，期望調整越光抽穗期，最終目的為建立越光近似同源系，以適合台灣地區種植與栽培。
依三個抽穗期基因於台農67號和越光的序列差異，設計三個功能性分子標幟做為前景篩選，分別為indel形式的Hd1功能性分子標幟、CAPs形式的Hd6功能性分子標幟與dCAPs形式的Ehd1功能性分子標幟。背景篩選的分子標幟則有87個，為越光與台農67號之間具多型性的SSR和indel分子標幟，其平均間距為17.3 cM。在育種流程中，以越光為輪迴親，台農67號為貢獻親的稉稉雜交族群，每世代皆使用三個功能性分子標幟篩選異質結合體（Hd1hd1 / Hd6hd6 / Ehd1ehd1），數量不等的多型性分子標幟篩選背景，應用於BC1F1、BC2F1與BC3F1各世代之篩選。由283株BC1F1中挑選出兩株當做父本進行回交越光，以64株BC2F1中挑選出四株當做父本進行回交越光，246株BC3F1中挑選出＃286-14-A23與＃286-85-A27，皆為Hd1hd1 / Hd6hd6 / Ehd1ehd1，分別帶有92.6％與90.8％越光基因體背景，進行自交與回交。目前進行至BC3F1，挑選出之＃286-14-A23與＃286-85-A27進行自交成BC3F2世代和回交成BC4F1。希冀在後續的分子輔助選種的協助下，可得到帶有不同抽穗期基因的近似同源系，從中評估挑選擁有越光優良米質且適合台灣地區種植的越光近似同源系。

關鍵字

越光 ； 台農67號 ； 抽穗期 ； 光週期 ； 分子輔助選種

並列摘要

The heading date of rice is the responds to diverse adaptation to different geographical distributions and seasons. The heading date also influences the rice vegetative stage, in which short vegetative stages reduce grain yield and quality. The elite rice cultivar, Koshihikari, possesses good yield and quality while planted in Japan; however, Koshihikari heads too early while planted by in Taiwan because of its photoperiod-sensitivity. A Taiwan elite cultivar, TNG67 is a photoperiod- insensitve variety and has been widely used as a priority germplam in rice breeding programs in Taiwan. Sequence alignment analyses of six cloned heading date genes between Koshihikari and TNG67 reveal that three heading date genes, Hd1, Hd6, and Ehd1, differ in sequence and function, accounting the variation of days to head in Koshihikari and TNG67. Therefore, the main goal of this study is to introgress the three heading date genes of TNG67 to Koshihikari by MAS, and finally to establish several NILs of Koshihikari with different heading dates, suitably cultivated in Taiwan.
According to the sequence variation of the three heading date genes, we designed three functional markers for foreground selection, which Hd1, Hd6, and Ehd1 were designed as indel, CAPs, and dCAPs markers, respectively. A total of 87 polymorphic markers of SSRs and indels, with an average distance of 17.3 cM, were employed as background selection. In the backcross recurrent selection, Koshihikar was served as the recurernt parent, and TNG67 was served as the donor parent. In each backcross generation, the three functional markers of heading date genes were used first to select individuals with Hd1hd1 / Hd6hd6 / Ehd1ehd1 for foreground selection, and then the selected individuals were subjected with various polymorphic markers for background selection. Three individuals selected from 283 BC1F1 by MAS were served as the male parents to backcross to Koshihikari; four individuals selected from64 BC2F1 by MAS were served as the male parents to backcross to Koshihikari; two individuals selected from 246 BC3F1 by MAS, which ＃286-14-A23 and ＃286-85-A27 possess Hd1hd1 / Hd6hd6 / Ehd1ehd1, and contain 92.6％ and 90.8％ of Koshihikari genome, respectively. Upto now, two BC3F1 individuals, ＃286-14-A23 and ＃286-85-A27, were selfed to establish BC3F2 and were served as the male parents to backcross to Koshihikari to establish BC4F1. In the future, sereval NILs of Koshihikari by furher MAS will be established and be evaluated for grain quality, yield and other agronomic traits. Finally, the optimized NILs will be promoted to cultivate in Taiwan.

並列關鍵字

Koshihikar ； Tainung 67 ； heading date ； photoperiod ； marker-assisted selection

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。

曾東海主撰。1999。稉稻。載於張彩泉主編，台灣稻作發展史。台灣省政府農林廳。

張瑪利、羅正宗、劉景平。2006。日長對水稻栽培品種抽穗及農藝性狀之影響。作物、環境與生物資訊 3: 147-158。

黃真生。1979。水稻品種台農67之育成。中華農業研究 28: 57-66。

盧虎生、劉韻華、中央氣象局。2006。臺灣優質水稻栽培之環境挑戰與因應措施。作物、環境與生物資訊 3: 297 - 306。