Impact of plant breeding on genetic diversity of agricultural crops: searching for molecular evidence

There is a long-standing concern that modern plant breeding reduces crop genetic diversity, which may have consequences for the vulnerability of crops to changes in pests, diseases, climate and agricultural practices. Recent molecular assessments of genetic diversity changes in existing genepools of major agricultural crops may shed some light on the impact of plant breeding on crop genetic diversity. Reviewing published assessments revealed different impacts of plant breeding on improved genepools, not only narrowing or widening their genetic base, but also shifting their genetic background. In general, the genome-wide reduction of crop genetic diversity accompanying genetic improvement over time is minor, but allelic reduction at individual chromosomal segments is substantial. More efforts are needed to assess what proportion of lost alleles is associated with undesirable traits.

[1]  D. Duvick Genetic diversity in major farm crops on the farm and in reserve , 1984, Economic Botany.

[2]  J. Jia,et al.  Impact of plant breeding on genetic diversity of the Canadian hard red spring wheat germplasm as revealed by EST-derived SSR markers , 2006, Theoretical and Applied Genetics.

[3]  S. Kresovich,et al.  Population Genetic Diversity in a Maize Reciprocal Recurrent Selection Program , 2005 .

[4]  J. Reif,et al.  Trends in genetic diversity among European maize cultivars and their parental components during the past 50 years , 2005, Theoretical and Applied Genetics.

[5]  F. Balfourier,et al.  SSR allelic diversity changes in 480 European bread wheat varieties released from 1840 to 2000 , 2005, Theoretical and Applied Genetics.

[6]  R. Zhou,et al.  Genetic diversity trend of common wheat (Triticum aestivum L.) in China revealed with AFLP markers , 2005, Genetic Resources and Crop Evolution.

[7]  J. Clarke,et al.  Allelic reduction and genetic shift in the Canadian hard red spring wheat germplasm released from 1845 to 2004 , 2005, Theoretical and Applied Genetics.

[8]  Yong-Bi Fu,et al.  Genetic diversity of Pakistan wheat germplasm as revealed by RAPD markers , 2005, Genetic Resources and Crop Evolution.

[9]  J. Reif,et al.  Wheat genetic diversity trends during domestication and breeding , 2005, Theoretical and Applied Genetics.

[10]  M. Cooper,et al.  Changes in Pedigree Backgrounds of Pioneer Brand Maize Hybrids Widely Grown from 1930 to 1999 , 2004 .

[11]  M. Yu,et al.  Registration of Root-Knot Nematode-Resistant Sugarbeet Germplasm M6-2 , 2004 .

[12]  H. Nybom Comparison of different nuclear DNA markers for estimating intraspecific genetic diversity in plants , 2004, Molecular ecology.

[13]  T. Efremova,et al.  The genetic diversity of old and modern Siberian varieties of common spring wheat as determined by microsatellite markers , 2004 .

[14]  R. Bernardo,et al.  Changes in genetic variance during advanced cycle breeding in maize , 2004 .

[15]  R. Ortiz,et al.  Breeding gains and changes in morphotype of Nordic spring wheat (1901–1993) under contrasting environments , 2003, Genetic Resources and Crop Evolution.

[16]  S. Hazen,et al.  Genetic diversity of winter wheat in Shaanxi province, China, and other common wheat germplasm pools , 2002, Genetic Resources and Crop Evolution.

[17]  P. N. Fox,et al.  Genetic diversity within Australian wheat breeding programs based on molecular and pedigree data , 2002, Euphytica.

[18]  S. Andersen,et al.  Diversity changes in an intensively bred wheat germplasm during the 20th century , 2002, Molecular Breeding.

[19]  W. Powell,et al.  A retrospective analysis of spring barley germplasm development from `foundation genotypes' to currently successful cultivars , 2000, Molecular Breeding.

[20]  K. Richards,et al.  Amplified fragment length polymorphism analysis of 96 Canadian oat cultivars released between 1886 and 2001 , 2004 .

[21]  D. Zhang,et al.  Assessing temporal changes in genetic diversity of maize varieties using microsatellite markers , 2004, Theoretical and Applied Genetics.

[22]  F. Balfourier,et al.  Molecular diversity in French bread wheat accessions related to temporal trends and breeding programmes , 2004, Theoretical and Applied Genetics.

[23]  G. Scoles,et al.  Allelic Diversity Changes in 96 Canadian Oat Cultivars Released from 1886 to 2001 , 2003 .

[24]  Yong-Bi Fu Applications of bulking in molecular characterization of plant germplasm: a critical review , 2003, Plant Genetic Resources.

[25]  R. Tuberosa,et al.  Microsatellite analysis reveals a progressive widening of the genetic basis in the elite durum wheat germplasm , 2003, Theoretical and Applied Genetics.

[26]  Yong-Bi Fu,et al.  RAPD Analysis of 54 North American Flax Cultivars , 2003 .

[27]  Seyed Abolghasem Mohammadi,et al.  Analysis of Genetic Diversity in Crop Plants—Salient Statistical Tools and Considerations , 2003 .

[28]  R. Koebner,et al.  Temporal flux in the morphological and molecular diversity of UK barley , 2003, Theoretical and Applied Genetics.

[29]  B. Baum,et al.  AFLP and pedigree-based genetic diversity estimates in modern cultivars of durum wheat [Triticum turgidum L. subsp. durum (Desf.) Husn.] , 2002, Theoretical and Applied Genetics.

[30]  H. Hopp,et al.  Quantitative evaluation of genetic diversity in wheat germplasm using molecular markers , 2001 .

[31]  R. Bernardo,et al.  Molecular marker diversity among current and historical maize inbreds , 2001, Theoretical and Applied Genetics.

[32]  R. Koebner,et al.  Temporal trends in the diversity of UK wheat , 2000, Theoretical and Applied Genetics.

[33]  K. Lamkey,et al.  Temporal changes in allele frequencies in two reciprocally selected maize populations , 1999, Theoretical and Applied Genetics.

[34]  J. Lenné,et al.  Agrobiodiversity: Characterization, Utilization and Management , 1999 .

[35]  D. Stuthman,et al.  Changes in genetic diversity during seven cycles of recurrent selection for grainyield in oat, Avena sativa L. , 1999 .

[36]  J. Lenné,et al.  Does plant breeding lead to a loss of genetic diversity , 1999 .

[37]  O. L. May,et al.  Changes in the genetic diversity of cotton in the USA from 1970 to 1995 , 1998 .

[38]  S. Tanksley,et al.  Seed banks and molecular maps: unlocking genetic potential from the wild. , 1997, Science.

[39]  R. Busch,et al.  Genetic Diversity among North American Spring Wheat Cultivars: I. Analysis of the Coeffecient of Parentage Matrix , 1997 .

[40]  Robert Tripp,et al.  Biodiversity and modern crop varieties: Sharpening the debate , 1996 .

[41]  O. Smith,et al.  Genetic Drift and Selection Evaluated From Recurrent Selection Programs in Maize , 1989 .

[42]  J. Murphy,et al.  Changes in genetic diversity in the red winter wheat regions of the United States. , 1986, Proceedings of the National Academy of Sciences of the United States of America.

[43]  T. S. Cox,et al.  Relationship Between Coefficient of Parentage and Genetic Similarity Indices in the Soybean 1 , 1985 .

[44]  J. Murphy,et al.  Impact of Plant Breeding on the Grain Yield and Genetic Diversity of Spring Oats 1 , 1983 .

[45]  A. J. Ullstrup The Impacts of the Southern Corn Leaf Blight Epidemics of 1970-1971 , 1972 .

[46]  T. G. Horsfall,et al.  Genetic vulnerability of major crops , 1972 .