- 期刊
分子標幟輔助耐鹽水稻之選育
Marker-Assisted Selection of Salt Tolerance in Rice (Oryza sativa L.)
摘要
本研究以稉型稻耐鹽品系SM61為貢獻親，而世界栽培面積廣泛的優良秈稻品種IR64為輪迴親，透過回交方式將SM61之耐鹽性轉移至IR64，過程中利用200 mM氯化鈉(NaCl)溶液的鹽分逆境處理挑選出耐鹽的植株，並於各回交世代F1進行分子標幟輔助背景選拔，結果發現各BC1F1、BC2F1及BC3F1世代回復輪迴親比率分別為75.0、89.0、96.4%，高於傳統回交方式之BC3F1世代回復至輪迴親之93.8%的結果，顯示利用分子標幟輔助可較快速回復輪迴親IR64之遺傳背景，提高耐鹽水稻新品種之選育效率。而以SM61、IR64及6個BC3F4品系於三葉齡、五葉齡、七葉齡及最高分蘗期等4個時期，分別以200 mM NaCl的鹽分逆境處理評估材料之耐鹽性表現，試驗發現ST12、ST18及ST59等3個品系之耐鹽性表現優於貢獻親SM61及輪迴親IR64，顯示已將SM61之耐鹽特性導入IR64中，培育出高耐鹽之秈型稻新品系。而進一步評估20個耐鹽品系(BC3F4)產量表現，結果發現各品系產量均可達5,000 kg ha^(-1)以上，顯示獲選之耐鹽品系皆已具有實際栽培價值，未來於命名成為新品種後，其將可供鹽分地水稻之栽培利用，進而增加未來國內外稻米糧食之生產。
並列摘要
The salt-tolerant mutant line 'SM61' was crossed to IR64, an elite indica variety which is widely grown in the world, to introgress gene(s) conferring salt tolerance to 'IR64' as the recurrent parent by backcrossing. The progenies of each backcross generation were screened salt tolerance by the treatment of 200 mM NaCl and consequently selected by markers for background selection to recover the recurrent parent's genome. The means of recurrent parent's genome were 75.0, 89.0 and 96.4% in selected BC1F1, BC2F1 and BC3F1 individuals, respectively. As compared to the mean recovery genome of BC3F1 plants by conventional backcrossing was 88.4%, background selection by marker-assisted selection (MAS) was more efficient to breed salt-tolerant lines. 'SM61', 'IR64' and six BC3F4 salt-tolerant lines derived from the backcross of 'SM61'/'IR64' were evaluated for salt tolerance under the treatment of 200 mM NaCl at three-leaf, five-leaf, seven-leaf, and after maximum tillering stages. Three salt-tolerant lines, 'ST12', 'ST18' and 'ST59', exhibited higher tolerance to salt stress than both the donor parent and the recurrent parent did, implying that the salt-tolerant characteristic of 'SM61' was successfully transferred to 'IR64' and generated new high salt-tolerant indica lines by MAS. In addition, the grain yields of twenty salt-tolerant BC3F4 lines were produced more than 5,000 kg per hectare, indicating that these twenty salt-tolerant lines can be grown in fields for cultivation. Hopefully these salt-tolerant lines will be registered as new rice varieties and be available for rice production on saline fields locally and internationally.