臺灣水稻抗白葉枯病研究回顧與育種策略

水稻白葉枯病係由Xanthomans oryzae pv. oryzae所引起的一種細菌性維管束病 害，其病原細菌在維管束中孳生繁殖及產生阻塞多醣體。初期病癥呈水浸狀，後 葉片維管束阻塞嚴重營養水份因而無法運輸，水浸狀病癥進而轉為波浪枯黃之病 斑。枯萎葉片相對減少水稻植株光合作用能力，間接影響稻米產量及品質。目前 水稻白葉枯病在臺灣每年將近2萬公頃稻田發生此病害，世界水稻生產區如亞洲、 非洲等地區均受其害。相關的研究在臺灣始自1968年，本報告將過去的研究，整 理分類為3部份，分別為病原發現及其生態、抗病種原遺傳與檢定、抗病育種及防 治策略，將之節錄後，再與國外相關研究相比較後，對未來臺灣抗白葉枯病育種 研究提出策略。 Bacterial blight (BB) is a serious disease caused by Xanthonomas oryzae pv. oryzae (Xoo) for rice production in Taiwan. Every year, around 20,000 ha or 10 percent of total rice field suffered from the epidemics of this disease in Taiwan. Breeding for varieties resistance to this disease has been utmost important in Taiwan. To cope with this problem, an integrated scheme of screening the resistance of breeding lines and varieties has been set up through cooperative efforts among different research units in Taiwan since 1975. Rice bacterial blight disease caused by a bacterial vascular disease, pathogenic bacteria propagated in the vascular bundles and produced many polysaccharides to block the vascular. Early symptoms were flooding-shaped and leaf vascular occlusion after high levels to inhibit the water and nutrient to be transported in the plants. Bacterial blight of rice currently in Taiwan occurs every year nearly 20,000 hectares of paddy fields. Bacterial blight was occurred in Taiwan began in 1968, reviews of past researches in this report, and departed in 3 parts, respectively for pathogen detection and ecology, disease resistant resource and its detection testing, and strategies of disease-resistant breeding and its control technology research and development. The strategy of disease-resistant breeding would be concerned to challenge the variation of the pathogen in the future

良質米育種的演變與成果

臺灣良質米育種早在民國60年代末期悄悄進行，當時以良質親本選擇與白米 外觀選拔為育種重點，臺中189號、臺農70號與臺南9號可為其中的代表。民國74 年至87年由稻作育種小組主導良質選育，採統一雜交、分區汰選品系的育種方式， 總計育成17個稉稻品種、1個秈稻品種、4個糯稻品種，曾列入良質米推薦品種有9 個，惟其中有9個為小組成立前由各場所選拔者。此時期的良質選育多以糙(白)米 外觀與產量為主，其他米質特性則在穩定世代後檢定。民國87年恢復各場所自行 雜交、選育與命名，總計87~95年間育成的品種有臺農71號、臺東30號等22個品種， 曾列入良質米推薦品種有5個，而在育種小組之下選育者有8個。在此期間各場所 的良質米選拔指標除糙(白)米外觀外，也運用食味計、味度計等相關儀器作為食味 選拔的指標，新品種的白米外觀明顯的優於舊品種，食味也增進中。在良質育種 目標漸傾向地區性的品種與多樣化與營養成份的領域，此種情形在95年水稻品種 納入植物品種及種苗法規範後更為明顯，累計至今已有19個品種申請品種權。調 查試驗改良場所對育種目標的排序，並進行加權平均後，各場所對育種目標的重 視程度分別為食味品質＞外觀品質＞產量或株型＞抗(耐)生物逆境＞抗(耐)環境逆 境＞貯藏性。 The good-quality rice breeding, was selected good-quality parents for crossing and good rice appearance during breeding process, was started in the late 1970’ decade. Taichung 189, Tainung 70 and Tainan 9 were breeding in this way at that time. The good-quality rice breeding was organized by The Rice Breeding Team, set up according to the policy of Taiwan Province Government, during 1985-1998, was crossed in the Taiwan Research Institute and Taichung District Agricultural Improvement Station and selected in different station during breeding descendants. The yield and rice appearance were the goals of good-quality rice and total 17 japonica, 1 indica, 4 glutinous rice varieties had been released during that time. 9 varieties had been selected by each station before 1985 and 9 varieties had been recommended good-quality rice by government. After 1998, the crossing and selecting of rice breeding are returned to each institutes and stations. Beside rice appearance, the eating quality, detected by AN-800 and MA-30A machines, were the goals of good-quality rice and total 22 rice varieties had been released during that time. 8 varieties had been selected by Taiwan Rice Breeding Team before 1998 and 5 varieties had been recommended good-quality rice by government. The rice appearance and eating quality of new varieties is brtter than that of olds’. After 2006, rice releasing system has been followed The Seeds and Seedlings of Plant Variety Law. The good-quality rice goal is extending to nutrition and alterative utilization. From that time, 19 varieties have been applied in this system. The good-quality rice breeding goals of research institute and stations have been investigated recently. The rank of good-quality rice breeding goals is follow by eating quality ＞ rice appearance ＞ yield or plant type ＞ biological stress tolerance ＞ physiological stress tolerance ＞ storage tolerance