Population Analysis of Fusarium graminearum from Wheat Fields in Eastern China

Phytopathology - Tập 92 Số 12 - Trang 1315-1322 - 2002
Liane Rosewich Gale1, L.-F. Chen, C. A. Hernick1, Kenzi Takamura1, Harold Kistler
1University of Minnesota Twin Cities

Tóm tắt

Wheat heads showing symptoms of Fusarium head blight were collected from four commercial fields in Zhejiang Province, China, an area where epidemics occur regularly. A total of 225 isolates were subjected to population-level analyses using restriction fragment length polymorphism (RFLP) as markers. Diagnostic RFLP markers established that all isolates belonged to Fusarium graminearum lineage 6. Nine polymorphic probes were hybridized to all isolates, resulting in 65 multilocus RFLP haplotypes (MRH). Probing with the telomeric clone pNla17, which reveals differences among isolates in the hypervariable subtelomeric region, differentiated the 65 MRH further into 144 clones. Mean gene diversity for the four field populations was similar, ranging from H = 0.306 - 0.364 over the nine RFLP loci for clone-corrected data. High levels of gene flow were inferred from a low level of population subdivision among all field populations, indicating that they were part of the same population. Pairwise linkage disequilibrium measures did not unequivocally support a random mating population, because one-third of locus pairs were significantly different from the null hypothesis of no-association between alleles. We speculate therefore that sexual recombination may not be frequent and that high levels of genotypic diversity may be maintained by relatively low selection pressure acting on a highly diverse population.

Từ khóa


Tài liệu tham khảo

10.1007/s002940000138

10.1094/MPMI-7-0196

10.1016/0147-5975(92)90007-E

Bowden, R. L., and Leslie, J. F. 1997. Diversity and sexuality in Gibberella zeae. Pages 35-39 in: Fusarium Head Scab: Global Status and Future Prospects. H. J. Dubin, L. Gilchrist, J. Reeves, and A. McNab, eds. CIMMYT, Mexico.

10.1094/PHYTO.1999.89.2.182

Bowden, R. L., Zeller, K. A., and Leslie, J. F. 2000. Population structure of Gibberella zeae in the Great Plains of North America. Pages 211-213 in: Proc. Int. Symp. Wheat Improvement for Scab Resistance. W. J. Raupp, Z. Ma, P. Chen, and D. Liu, eds. Nanjing Agricultural University, Jiangsu, China.

10.1046/j.1439-0434.1999.147005307.x

Chen, L. F., Bai, G. H., and Desjardins, A. E. 2000. Recent advances in wheat head scab research in China. Pages 258-273 in: Proc. Int. Symp. Wheat Improvement for Scab Resistance. W. J. Raupp, Z. Ma, P. Chen, and D. Liu, eds. Nanjing Agricultural University, Jiangsu, China.

10.1006/fgbi.2001.1296

10.1093/genetics/131.2.479

10.1094/PHYTO.1997.87.4.414

10.1094/PDIS.1999.83.7.662

10.2307/2532702

Gale, L. R. 2002. The population biology of Fusarium species causing head blight of grain crops in: Fusarium Head Blight of Wheat and Barley. K. J. Leonard and W. R. Bushnell, eds. The American Phytopathological Society, St. Paul, MN.

10.1139/g63-009

10.1094/PDIS.2000.84.9.1021

10.1046/j.1365-3059.1997.d01-88.x

10.1111/j.1574-6968.1997.tb12783.x

10.1094/PDIS.1997.81.12.1340

10.1007/BF01877051

10.1046/j.1439-0434.2001.00687.x

10.1146/annurev.phyto.34.1.457

Nei, M. 1987. Molecular Evolutionary Genetics. Columbia University Press, New York.

10.1073/pnas.130193297

10.1007/s002849900108

10.1111/j.1365-3059.1995.tb02773.x

10.1016/S0959-437X(97)80046-9

10.1094/PHYTO.1999.89.8.623

10.1094/PHYTO.1998.88.10.1087

Sambrook, J., Fritsch, E. F., and Maniatis, T. 1989. Molecular Cloning: A Laboratory Manual. 2nd ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, NY.

Schilling A. G., 1996, Sydowia, 48, 71

10.1094/Phyto-86-515

Slatkin M., 1994, Genetics, 137, 331, 10.1093/genetics/137.1.331

Tajima, F. 1993. Measurement of DNA polymorphism. Pages 37-59 in: Mechanisms of Molecular Evolution. Introduction to Molecular Paleopopulation Biology. N. Takahata and A. G. Clark, eds. Sinauer Associates, Sunderland, MA.

10.1094/PDIS.2001.85.4.404

Wang, Y. Z. 1997. Epidemiology and management of wheat scab in China. Pages 97-105 in: Fusarium Head Scab: Global Status and Future Prospects. H. J. Dubin, L. Gilchrist, J. Reeves, and A. McNab, eds. CIMMYT, Mexico.

10.2307/2408641

10.1006/fgbi.2000.1226

Zeller, K. A., Bowden, R. L., and Leslie, J. F. 2000. AFLP diversity of Fusarium graminearum (Gibberella zeae) epidemic populations. Mycologia 51(suppl.):69.