水稻‘LTH’單基因系與‘CO 39’近同源系對台灣稻熱病菌之反應

Response of Rice Varieties ‘LTH’ Monogenic Lines and‘CO 39’ Near-Isogenic Lines to Rice Blast

廖大經(Dah-Jing Liao) ； 陳隆澤(Lung-Che Chen) ； 吳志文Chih-Wen Wu ； 鍾嘉綾(Chia-Lin Chung)

《台灣農業研究》 65卷1期 (2016/03) Pp. 8-17

https://doi.org/10.6156/JTAR/2016.06501.02

摘要

廖大經、陳隆澤、吳志文、鍾嘉綾。2016。水稻 ‘LTH’ 單基因系與 ‘CO 39’ 近同源系對台灣稻熱病菌之反應。台灣農業研究 65(1):8–17。本研究探討由國際水稻研究所 (International Rice Research Institute; IRRI) 引進之 ‘LTH’ 單基因系及 ‘CO39’ 近同源系等攜帶已知抗病基因之稻熱病判別品系，2011–2014 年共5 個期作於行政院農業委員會農業試驗所嘉義分所進行旱田式稻熱病病圃之抗性反應。結果顯示，37.5% 之 ‘LTH’ 單基因系及71.4% 之 ‘CO 39’近同源系，罹病等級中位數為4 級或以下，即抗病性為中抗級或以上。其中，並以 ‘LTH’ 單基因系之Piz-5 [來自IRBLz5-CA 與IRBLz5-CA(R)]、Pib (來自IRBLb-B)、Pi12(t) ( 來自IRBL12-M) 及Pita2 (來自IRBLta2-Pi 與IRBLta2-Re)，以及 ‘CO 39’ 近同源系之Pik [來自IRBLk-Ka(CO)]、Pikh [來自IRBLkh-K3(CO)] 及Pita2[來自IRBLta2-IR64(CO)] 等抗病基因之抗性最為穩定，表示這些抗病基因可能對病圃中大多數稻熱病菌生理小種具有抗性，抗病幅度較廣。某些貢獻親本來源相同的抗病基因，在 ‘LTH’ 及 ‘CO 39’ 兩種遺傳背景下的抗性反應不一致，例如來自 ‘Kanto 51’ 的Pik 以及來自 ‘K60’ 的Pik-p，在 ‘CO 39’ 背景下的罹病反應表現為中等抗病，但在 ‘LTH’ 背景表現為極感病，原因可能是Pik 及Pik-p 之抗性必須在具有其他抗病基因存在或秈稻背景下效應較強。此外，來自親本 ‘K3’ 的Pik-h 以及來自 ‘C101LAC’ 的Pi1，在 ‘LTH’ 背景下所貢獻之抗性幅度較高，可使極感病之 ‘LTH’ 罹病度下降3–4 級，但在 ‘CO 39’ 背景下罹病度則只下降1 級。已知 ‘CO39’ 帶有Pia 及Pi-CO39(t) 兩個抗性基因，因此Pik-h 及Pi1 的表現可能受 ‘CO 39’ 背景中的抗性效應所遮蔽。由試驗結果，建議在台灣使用 ‘LTH’ 背景的判別品種，可避免檢定結果受內生遺傳背景遮蔽效應之影響，對於生理小種的鑑別度可能較佳。本研究亦發現到，某些帶相同抗性基因之判別品種與其貢獻親之抗病反應不一致，除了遺傳背景之差異外，亦可能與某些貢獻親如 ‘BL1’ 及 ‘Toride 1’ 等帶有1 個以上抗病基因，不同抗病基因之效應而使貢獻親更為抗病有關。

關鍵字

agnaporthe oryzae ； 病圃 ； 判別品系 ； 抗病基因

並列摘要

Liao, D. J., L. C. Chen, C. W. Wu, and C. L. Chung. 2016. Response of rice varieties ‘LTH’ monogenic lines and ‘CO 39’ near-isogenic lines to rice blast. J. Taiwan Agric. Res. 65(1):8-17. Two sets of rice blast differential lines introduced from IRRI, ‘LTH' monogenic lines (MLs) and ‘CO 39’ near isogenic lines (NILs), were tested for response to rice leaf blast at the upland blast nursery at Chiayi Agricultural Experiment Branch, Taiwan Agricultural Research Institute for 5 cropping seasons during 2011-2014. The results showed that 37.5% of the ‘LTH’ MLs and 71.4% of the ‘CO 39’ NILs exhibited moderate to high resistance (disease severity ≤ 4). In particular, Piz-5 [in IRBLz5-CA and IRBLz5-CA(R)], Pib (in IRBLb-B), Pi12(t) (in IRBL12-M), and Pita2 (in IRBLta2- Pi) consistently showed high resistance, indicating that the four resistance genes might be incompatible with most of the Magnaporthe oryzae races in the nursery, therefore their resistance is likely to be more broad-spectrum. It was observed that some resistance genes had different reactions in the ‘LTH’ and ‘CO 39’ genetic backgrounds. For instance, Pik (from ‘Kanto 51’) and Pik-p (from ‘K60’) were moderately resistant in ‘CO 39’ background but highly susceptible in ‘LTH’ background, suggesting that their resistance may be more effective in the Indica background or the background containing other resistance gene(s). Pik-h (from ‘K3’) and Pi1 (from ‘C101LAC’) conferred stronger resistance in ‘LTH’ background (reduction of 3-4 scales on severity) than in 'CO 39’ background (reduction of 1 scale on severity), which may be due to the mask effect contributed from the resistance of Pia and Pi- CO39(t) in ‘CO 39’. Because of the potential interference of mask effect in ‘CO 39’, the ‘LTH’ MLs can be a better differential system for the identification of effective R genes in Taiwan. It was also found that some differential lines and their donor parents reacted differently to blast, possibly due to the genetic background effects and/or the accumulative effects of multiple R genes in the genomes. ‘BL1’ and ‘Toride 1’, the donor lines carrying more than one R genes, showed higher resistance than their corresponding ‘LTH’ and ‘CO 39’ differential lines.

並列關鍵字

Magnaporthe oryzae ； Blast nursery ； Differential lines ； Resistance genes