国外引进水稻种质资源的稻瘟病抗性基因检测与评价

为了筛选出福建省水稻稻瘟病重发区育种中可利用的新抗性资源,在福建省上杭县对156份外引水稻种质资源进行了2年田间自然诱发鉴定,并对Pi2、Pi9、Pi5、Pi54、Pikm、Pita、Pia和Pib等8个稻瘟病抗性基因做了分子检测。结果表明:156份资源对苗瘟、叶瘟、穗颈瘟和综合抗性表现抗病的分别有10份、14份、29份和26份,且苗瘟抗性级别与叶瘟抗性级别(r=0.816,P<0.01)、苗瘟抗性级别与穗颈瘟抗性级别(r=0.347,P<0.01)、以及叶瘟抗性级别与穗颈瘟抗性级别(r=0.344,P<0.01),均呈极显著正相关。分子标记检测到携带稻瘟病抗性基因Pi9、Pi2、Pi54、Pikm、Pi5、Pib、Pia和Pita的水稻资源分别有1、6、20、22、37、88、101和106份,其中携带稻瘟病抗性基因Pi9和Pi2的水稻资源的抗性表现较好,表现抗病的超过60%,携带其他稻瘟病抗性基因的水稻资源表现抗病的均在50%以下;水稻资源携带0~6个稻瘟病抗性基因,随着携带抗性基因数目增加,抗病率呈上升趋势,综合抗性等级呈下降趋势。进一步研究发现,携带Pi9+Pi5+Pikm+Pia、Pi5+Pib+Pita+Pikm+Pia和Pi2+Pi54+Pib+Pita+Pikm+Pia等3个基因型的水稻资源,稻瘟病抗性较好。最后,筛选了8份稻瘟病抗性较好的材料,提供育种者参考、利用。

Detection and Evaluation of Blast Resistance Genes in Exotic Rice Germplasm Resources

In order to identify new resistant resources of 156 exotic rice germplasm accessions for breeding in Fujian Province,test for rice blast resistance was conducted at two calendar years in experimental plot in Shanghang,Fujian.Genotypes carrying any of rice blast resistance genes Pi2,Pi9,Pi5,Pi54,Pikm,Pita,Pia and Pib were detected by molecular selection markers.As a result,10,14,29 and 26 accessions showed resistant seedling blast,leaf blast,neck blast and comprehensive resistance,respectively.Furthermore,the correlation analysis suggested significant positive correlations between seedling blast and leaf blast(r=0.816,P<0.01),seedling blast and neck blast(r=0.347,P<0.01),and leaf blast and neck blast(r=0.344,P<0.01).Marker assisted selection indicated 1,6,20,22,37,88,101 and 106 rice accessions,which harbored the resistance genes Pi9,Pi2,Pi54,Pikm,Pi5,Pib,Pia and Pita,respectively.60%of accessions containing either of Pi9 and Pi2 genes were resistant to rice blast.A subset of rice accessions was found with stacking of 0 to 6 blast resistance genes.An elevation on rice blast resistance was observed if several resistance genes were present in an accession.For example,a combination of resistance genes Pi9+Pi5+Pikm+Pia,Pi5+Pib+Pita+Pikm+Pia and Pi2+Pi54+Pib+Pita+Pikm+Pia displayed the better resistance.Finally,8 rice blast resistant genotypes were identified with potential for rice breeding.