@article{oai:niigata-u.repo.nii.ac.jp:00028384, author = {竹内, 一成 and 福山, 利範}, issue = {2}, journal = {新潟大学農学部研究報告, 新潟大学農学部研究報告}, month = {Mar}, note = {北陸および東北地域のオオムギ雲形病菌の病原性変異を調査し、過去(1950年代、1990年代)の報告との比較によりその変遷について調べた。2007年春に北陸・東北地方の22圃場から45菌株を採集し、従来のレース同定に用いられてきた10判別品種への接種試験により、新規の13レースを含む15レースを同定した。調査地域では、以前よりも病原性の強いレースが優占しており、病原性変異の多様化の進んでいることが示された。また、これまで高度抵抗性を示してきたTennessee WinterおよびAtlas 46の罹病化傾向が明らかになった。こうしたレース変遷により、北陸・東北地域における抵抗性遺伝子源の探索や系統選抜には、これまでのJ-4aの他にJ-6あるいはJ-10を使うことを提案した。つぎに、国際的に使われている16判別品種を加えた26品種における接種試験の反応パターンおよび各品種の真性抵抗性遺伝子型に基づいて主成分分析を行い、判別品種の構成について検討した。26品種は6群に分類され、従来の10判別品種とは異なる特徴を示す3群から追加すべき判別品種候補として、Osiris、Jet、Nigrinudum およびC.I.4368を選定した。さらに、抵抗性程度の判定方法についても議論した。, Variation of pathogenicity in Rhynchosporium secalis distributed in Hokuriku and Tohoku districts was investigated, and changes in pathogenicity were compared with those already reported in 1950's and 1990's. Forty five isolates were classified into 15 races through the inoculation test by 10 differential cultivars used in the previous reports. Out of 15 races, 13 were new and most of them were more pathogenic than those of the past, which showed the progress of pathogenicity to the differentials, e.g. some isolates were found to be pathogenic to Tennessee Winter and Atlas 46 which had been highly resistant to the pathogen distributed in Hokuriku and Tohoku districts. With reference to the change of pathogenicity, it was suggested that J-6 and/or J-10 should be added to J-4a which was already used for the screening of resistance of genetic resources or breeding process. To obtain more appropriate composition of the differentials, reaction patterns to the pathogen and genotypes for the resistance in the 10 differentials and 16 internationally used ones were analyzed by the principal component analysis. A total of 26 differentials were classified into 6 groups. Since 3 out of 6 groups did not include 10 differentials, Osiris, Jet, Nigrinudum and C.I.4368 were recommended as newly added differential cultivars. Furthermore, evaluating method for the degree of susceptibility was discussed.}, pages = {149--157}, title = {北陸・東北地方におけるオオムギ雲形病菌のレース分布および変遷とその同定に関する提案}, volume = {61}, year = {2009} }