• 作者： 吳信淦; 陳昌隆; 王玉斌
• 作者服務機構： 中央研究院植物研究所
• 中文摘要： 本研究預期目標，在從直型、橫型抗病性的效果，探側稻抗稻熱病的抗病性是否也屬此兩型，期對抗稻熱病育種有所裨益。 從稻品種（系）在病圃發病的遲早及病勢進展的快慢，初步認定稻有此兩型抗病性。進一步分析，得知稻品種與稻熱病菌小種的連應有顯著差別，是為稻具直型抗病性的證據。本省小種的分布，頻度最高的為IG-2及II-1，次高的為IF-4及IH-1等；由此推論，本省稻品種的直型抗病性，主由抗病基因G、H及F等控制，此等基因的強度經測定為F>H>G。 橫型抗病性的測定，雖已除去Vertifolia效應的干擾，對小種IF-4同為感病的四品種（系）中，系比622002號有橫型抗病性；對四個小種均感病的七品種（系）間，未曾顯示何者有橫型抗病性。國外諸學者測定結果，則顯示此兩型抗病性常相混於同一品種（系）內。 基於本省稻熱病菌歷年的分布，以及現行栽培品種、新推廣品種對彼等抗感的表現，曾建議本省稻熱病的短程防治，為在易發病地區以抗病品種取代目前的感病品種。中程防治，宜將直型抗病基因輪迴使用或組台成混合品種或多品系品種使用。長程的防治則宜繼續發掘橫型抗病性，並與直型的配合使用。同等重要的，要在各機構人員的合作下加強有關的基本研究。
• 英文摘要： The purpose of this research is to examinewhether rice has both vertical and horizontalresistances to blast disease. It is hoped that theresult of this work would be helpful in planningrice breeding programs. Field survey in 1975 showed that theinitiation of disease of several cultivars inlocal blast nurseries was delayed for severaldays, while some others kept their diseasedevelopment slow. It was primarily assumedthat both types of resistance existed inrice. Further evidence for vertical resistancewas obtained in 1977 from variance analysisin which difference of the interactions betweencultivar and race was significant. Subsidiaryevidence from other workers was that riceresistance to blast disease is usually controlledby a few major genes, and is completebut not lasting, it could be concluded thatrice has vertical resistance. Based on thefact that the commonest races in this island areIG-2 and II-1 which together account for 90%of the total number of isolates, next in abund-ance are IF-4 and IH-1 and that all these fourraces are those with one virulence except II-1,it was deduced that the vertical resistanceembodied in local cultivars is controlled byresistance genes such as G, H or F. Thestrength (or quality) of those genes wasestimated by the relative half-life of the matchedraces. As a result, gene F is stronger (orbetter) than gene H which in turn is strongerthan gene G. The measurement of horizontal resistancewas not very successful although the Vertifoliaeffect has been excluded. Only one line(622002) out of four, all susceptible to theinoculated race IF-4, showed significant dif-ference. No such difference was found in anothercomparison consisting of seven cultivars whichare all susceptible to the same set of racesinoculated. It seemed that the two types ofresistance were usually mingled in rice cultivars(or lines) so far reported by the foreign workers. Owing to the susceptibility of the mostpopular cultivars as well as of the newlyreleased ones to the local main races, sugges-tions were made to control blast disease in thisisland as follows: (1) to substitute susceptiblerice cultivars as soon as possible by availableresistant ones especially at areas apt to a blastepidemic; (2) to use rice vertical resistance ina well planned way such as using genesrecurrently or composing genes in a compositeor multiline cultivar; (3) to have an efficientissue in measuring and accumulating ricehorizontal resistance and finally to combine itwith the vertical; (4) to strengthen the basicresearches concerning blast disease control withcooperative efforts among institutions.
• 中文關鍵字： --
• 英文關鍵字： --