Population structure of seedborne Phaeosphaeria nodorum on New York wheat

被引:33
作者
Bennett, RS [1 ]
Milgroom, MG [1 ]
Bergstrom, GC [1 ]
机构
[1] Cornell Univ, Dept Plant Pathol, Ithaca, NY 14853 USA
关键词
inoculum sources;
D O I
10.1094/PHYTO-95-0300
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Population genetic and epidemiological studies have resulted in different hypotheses about the predominant source of primary inoculum in the Phaeosphaeria nodorum-wheat pathosystern (i.e.. sexually derived. windborne ascospores versus asexual or seedborne inoculum). We examined the genetic structure of seedborne Populations of P. nodorum as a further step toward evaluating the hypothesis that seedborne inoculum is an important contributor to foliar epidemics in New York's rotational wheat fields. In all. 330 seedborne isolates from seven field Populations were genotyped at 155 amplified fragment length polymorphisin loci. Seedborne Populations possessed high levels of genotypic diversity. with Virtually every isolate (326/330) having a Unique haplotype. As in previous population genetic Studies Of P. nodorum, We found low levels of gametic disequilibrium, although we could reject the null hypothesis of random mating with the index of association test for two populations. Thus. genotypically diverse and seemingly panmictic populations of P. nodorum that have been observed in wheat foliage could be derived from seedborne primary inoculum. Although sexual reproduction and recombination may contribute to the diversity of foliar populations of P. nodorum. population genetic data do not rule out seed as a source of primary inoculum. Further experimentation will be needed to determine definitively the relative importance of windborne ascospores and seedborne asexual inoculum in epidemics of Stagonospora nodorum blotch in New York.
引用
收藏
页码:300 / 305
页数:6
相关论文
共 55 条
[1]  
Agapow PM, 2001, MOL ECOL NOTES, V1, P101, DOI 10.1046/j.1471-8278.2000.00014.x
[2]   Genotyping gene genealogies and genomics bring fungal population genetics above ground [J].
Anderson, JB ;
Kohn, LM .
TRENDS IN ECOLOGY & EVOLUTION, 1998, 13 (11) :444-449
[3]   Seasonal patterns of spore dispersal of Phaeosphaeria spp. and Stagonospora spp. [J].
Arseniuk, E ;
Góral, T ;
Scharen, AL .
PLANT DISEASE, 1998, 82 (02) :187-194
[4]   INCIDENCE OF SEPTORIA-NODORUM IN WHEAT SEED AND ITS EFFECTS ON PLANT-GROWTH AND GRAIN-YIELD [J].
BABADOOST, M ;
HEBERT, TT .
PLANT DISEASE, 1984, 68 (02) :125-129
[5]   Ascospores are a source of inoculum of Phaeosphaeria nodorum, P-avenaria f. sp avenaria and Mycosphaerella graminicola in Western Australia [J].
Bathgate, JA ;
Loughman, R .
AUSTRALASIAN PLANT PATHOLOGY, 2001, 30 (04) :317-322
[6]   Identity and conservation of mating type genes in geographically diverse isolates of Phaeosphaeria nodorum [J].
Bennett, RS ;
Yun, SH ;
Lee, TY ;
Turgeon, BG ;
Arseniuk, E ;
Cunfer, BM ;
Bergstrom, GC .
FUNGAL GENETICS AND BIOLOGY, 2003, 40 (01) :25-37
[7]   SAMPLE SIZES REQUIRED TO DETECT LINKAGE DISEQUILIBRIUM BETWEEN 2 OR 3 LOCI [J].
BROWN, AHD .
THEORETICAL POPULATION BIOLOGY, 1975, 8 (02) :184-201
[8]  
BROWN AHD, 1980, GENETICS, V96, P523
[9]  
BROWN JKM, 1999, STRUCTURE DYNAMICS F
[10]   Molecular markers reveal cryptic sex in the human pathogen Coccidioides immitis [J].
Burt, A ;
Carter, DA ;
Koenig, GL ;
White, TJ ;
Taylor, JW .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (02) :770-773