利用分子標幟輔助導入Saltol QTL提升水稻「台稉九號」之耐鹽性

The Introgression of Saltol QTL into 'TK9' to Increase Salinity Tolerance by Using Marker-Assisted Selection

溫甯翔(Ning-Hsiang Wen) ； 郭介煒(Chieh-Wei Kuo) ； 郭素真(Su-Chen Kuo) ； 林彥蓉(Yann-Rong Lin) ； 吳永培(Yong-Pei Wu)

《台灣農業研究》 65卷3期 (2016/09) Pp. 328-347

https://doi.org/10.6156/JTAR/2016.06503.10

摘要

本研究利用台灣優質稉稻品種「台稉九號」('TK9')為輪迴親，耐鹽秈稻品種'Pokkali' 為貢獻親，利用分子標幟輔助回交法將'Pokkali'之Saltol QTL導入'TK9'中。過程中各回交世代均先進行Saltol QTL之前景選拔，獲選後代再經分子標幟輔助之背景選拔。結果發現帶Saltol QTL對偶基因之回交子代，其BC_1F_1、BC_2F_1及BC_2F_2世代獲選植株遺傳背景回復至輪迴親比率平均分別為71.5、85.4 及82.7%。與傳統回交育種BC_2F_1理論值87.5%相較，遺傳背景回復率有稍低的現象，顯示兩親本間可能遺傳背景較遠或發生遺傳拖曳之現象。又'Pokkali'、CWY981126、'IR64'及10個BC_2F_3品系於五葉齡期分別以100、150、200、250 及300 mMNaCl溶液進行鹽分逆境處理，結果'Pokkali'在100、150及200 mM NaCl 等鹽分濃度下均有高的耐鹽性表現，而BC_2F_3回交後代則以STK7及STK8等2個品系耐鹽性表現較佳。而相同材料分別於五葉齡及最高分蘖期以200 mM NaCl逆境進行不同生長時期耐鹽性評估，其中秧苗五葉齡鹽分逆境處理下，以品系STK8的耐鹽等級表現最佳，而STK4及STK7亦有不錯的耐鹽性表現；至於成株期之最高分蘖期則以STK7及STK8的耐鹽性表現最佳，由回交品系BC_2F_3耐鹽表現，顯示本試驗已順利將Saltol QTL導入'TK9'中，且成功培育具優良耐鹽性之BC_2F_3回交品系，未來可供國內鹽化土壤栽培利用。

關鍵字

分子標幟輔助選拔 ； 耐鹽 ； 水稻

並列摘要

In this study, japonica cv. 'TK9', a rice variety with high quality in Taiwan, was used as the recurrent parent and indica cv. 'Pokklali', a salt-tolerant variety with Saltol, was used as the donor parent. Marker-assisted backcross was applied to introgress Saltol QTL from 'Pokkali' to 'TK9'. For each backcross generation, the foreground selection was conducted first, and the selected progenies were subsequently subjected to background selection by marker-assisted selection. Among the backcross progeny carrying Saltol QTL, the average recovered rates of genetic background of the recurrent parent in BC_1F_1, BC_2F_1, and BC_2F_2 generations were 71.5, 85.4, and 82.7%, respectively. In comparison with the theoretical value of traditional backcross breeding of BC_2F_1, 87.5%, the recurrent parent genome recovered rate of BC_2F_2 has decreased, indicating the genetic background between parents were quite different or the condition of genetic dragging occurred. In addition, 'Pokkali', CWY981126, 'IR64', and ten lines of BC_2F_3 were treated with five concentrations of saline soution, 100, 150, 200, 250, and 300 mM of NaCl, at the fifth-leaf seedling stage. The results showed that 'Pokkali' expressed high salt-tolerance under 100, 150, and 200 mM NaCl. Moreover, STK7 and STK8, the backcross progenies of BC_2F_3, performed better salt-tolerance. Under the condition of 200 mM NaCl, STK8 had the best salt tolerance, followed by STK4 and STK7, at the fifth-leaf stage. STK7 and STK8 had best salt tolerance at active tillering stage. The Saltol QTL was successfully introgressed into 'TK9' by the evidence of salinity tolerance in the selected backcross progenies. The backcross lines of BC_2F_3 with good salinity tolerance have great potential to be developed into cultivars for growing in salt affected areas in Taiwan in the future.

並列關鍵字

Marker-Assisted Selection ； Salt tolerance ； Rice