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- Description:
- Includes references
- Author:
- Coates, B.S. , Hellmich, R.L. , Lewis, L.C.
- Subject:
- Beauveria bassiana , alleles , genetic variation , microsatellite repeats , host range , geographical variation , polymerase chain reaction , Beauveria , Beauveria brongniartii , pathogenicity , ecotypes , genetic markers , molecular genetics , strains , strain differences , nucleotide sequences , species differences
- Collection:
- Journal Articles, USDA Authors, Peer-Reviewed
- Year:
- 2002
- Description:
- The avirulence gene AVR-Pita of Magnaporthe oryzae determines the efficacy of the resistance gene Pi-ta in rice. The structures of the AVR-Pita alleles in 39 US isolates of M. oryzae were analyzed using polymerase chain reaction. A series of allele-specific primers were developed from the AVR-Pita gene to examine the presence of AVR-Pita. Orthologous alleles of the AVR-Pita gene were amplified from avirulent isolates. Sequence analysis of five alleles revealed three introns at identical positions in the AVR-Pita gene. All five alleles were predicted to encode metalloprotease proteins highly similar to the AVR-Pita protein. In contrast, the same regions of the AVR-Pita alleles were not amplified in the most virulent isolates, and significant variations of DNA sequence at the AVR-Pita allele were verified by Southern blot analysis. A Pot3 transposon was identified in the DNA region encoding the putative protease motif of the AVR-Pita protein from a field isolate B2 collected from a Pi-ta-containing cultivar Banks. These findings show that transposons can contribute to instability of AVR-Pita and is one molecular mechanism for defeating resistance genes in rice cultivar Banks.
- Author:
- Zhou, E.X. , Jia, Y.L. , Singh, P. , Correll, J.C. , Lee, F.N.
- Subject:
- Magnaporthe , plant pathogenic fungi , genes , virulence , alleles , introns , DNA primers , polymerase chain reaction , nucleotide sequences , transposons , pathogenicity , blast disease , Oryza sativa , rice
- Collection:
- Journal Articles, USDA Authors, Peer-Reviewed
- Year:
- 2007
