多年生稻白叶枯病抗性评价

Identification of Bacterial Blight Resistance in Perennial Rice

利用长雄野生稻地下茎无性繁殖特性培育多年生稻已经成功,并在生产上进行了示范推广。为明确多年生稻品种(系)对白叶枯病的抗性表现,通过田间病情调查、抗性水平鉴定和水稻白叶枯病抗性基因检测3种方法,对多年生稻品种(系)多年生稻23(简称PR23,下同)、云大24(PR24)、云大25(PR25)、云大101(PR101)、云大107(PR107)及其父本长雄野生稻、母本RD23和F1(RD23/长雄野生稻)的白叶枯病抗性进行评价。结果表明,长雄野生稻高抗白叶枯病;尽管PR23、PR24、PR25、PR107携带白叶枯病抗性基因Xa1、Xa4、Xa23、xa25的等位基因,但在田间自然发病条件下均易感白叶枯病,说明这几个抗性基因对这4个多年生稻品种(系)不起抗病作用;而PR101在田间自然发病条件下表现为抗白叶枯病,并含有白叶枯病抗性等位基因xa25、Xa27,说明这2个基因可能是PR101抗白叶枯病的基因。本研究结果为明确多年生稻对白叶枯病菌的抗病反应,以及抗白叶枯病育种和多年生稻生产布局提供了一定依据。

Perennial rice(PR),using vegetative propagation via Rhizome as perenniality donor from Oryza longistaminata,has been bred successfully and demonstrated widely.In order to clarify the resistance performance of perennial rice varieties(lines)to bacterial leaf blight,the perennial rice varieties(lines)PR23,PR24,PR25,PR101,PR107,and their male Oryza longistaminata,female parents RD23 and F1(RD23/Oryza longistaminata)were used as the materials to evaluate their resistance to bacterial blight by three methods:field disease investigation,resistance level identification and rice bacterial blight resistance gene detection.The results showed that,O.longistaminata presents high resistance to bacterial blight.Although PR23,PR24,PR25,PR107 carry the alleles of bacterial blight resistance genes Xa1,Xa4,Xa23,xa25,but they are all susceptible to bacterial blight in the field.It shows that these resistance genes do not play a role in disease resistance in these four perennial rice varieties(lines).PR101 shows resistance to bacterial blight under natural disease conditions in the field,and contains the bacterial blight resistance alleles xa25,Xa27,indicating that these two genes may be PR101 resistance genes to bacterial blight.The results provided a basis and strategy for both bacterial blight resistance breeding and application of perennial rice in future.