Theoretical and Applied Genetics

, Volume 83, Issue 3, pp 321–329

Population genetics of colonizing success of weedy rye in Northern California

  • M. Sun
  • H. Corke
Originals

Summary

Genetic parameters of 11 weedy rye populations located in California's northern mountain area and the adjoining Oregon border were compared with those of the putative parents, wild species Secale montamim and cultivated rye S. cereale. All weedy populations exhibited high levels of genetic variation as determined by isozyme analysis. On average, 44% of the isozyme loci were polymorphic, total genetic diversity was 0.30; and number of alleles per locus was 1.65. High genetic identities, averaging 0.994 ± 0.005 between populations, indicated that little genetic differentiation has occurred among these weedy populations since the initial colonization. Lack of population differentiation could be attributed to a wind-pollinated, self-incompatible breeding system resulting in extensive gene flow among weedy populations, and between weedy populations and local cultivars of rye. Multilocus outcrossing rates of weedy populations ranged from 0.86 to 0.97. The estimated levels of gene flow using the private-alleles method were high among weedy populations, and between cv ‘Merced’ and weedy populations, with estimated Nm values of 14.50 and 8.21, respectively. The colonizing success of weedy rye is discussed and a strategy for its conservation recommended.

Key words

Colonization Genetic diversity Outcrossing rate Gene flow 

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References

  1. Allard RW (1965) Genetic systems associated with colonizing ability in predominantly self-pollinated species. In: Baker HG, Stebbins GL (eds) Genetics of colonizing species. Academic Press, New York, pp 49–75Google Scholar
  2. Baker HG (1955) Self-compatibility and establishment after “long-distance” dispersal. Evolution 9:347–349Google Scholar
  3. Baker HG, Stebbins GL (1965) Genetics of colonizing species. Academic Press, New YorkGoogle Scholar
  4. Barrett SCH, Husband BC (1990) The genetics of plant migration and colonization. In: Brown AHD, Clegg MT, Kahler AL, Weir BS (eds) Plant population genetics, breeding and genetic resources. Sinauer Associates, Sunderland, Mass., pp 254–277Google Scholar
  5. Barrett SCH, Richardson BJ (1985) Genetic attributes of invading species. In: Grover RH, Burdon JJ (eds) The ecology of biological invasions: an Australian perspective. Australian Academy of Science, Jacaranda Publ, Canberra, pp 21–33Google Scholar
  6. Barton NH, Slatkin M (1986) A quasi-equilibrium theory of the distribution of rare alleles in a subdivided population. Heredity 56:409–415Google Scholar
  7. Brown AHD (1979) Enzyme polymorphism in plant populations. Theor Popul Biol 15:1–42Google Scholar
  8. Brown AHD, Marshall DR (1981) Evolutionary changes accompanying colonization in plants. In: Scudder GGE, Reveal JL (eds) Evolution today. Proceedings of the second international congress of systematic and evolutionary biology, Carnegie Mellon University, Pittsburgh, pp 351–363Google Scholar
  9. Haldane JBS (1930) A mathematical theory of natural and artificial selection. (Part VI, isolation). Proc Cambridge Philos Soc 26:220–230Google Scholar
  10. Hamrick JL (1987) Gene flow and distribution of genetic variation in plant populations. In: Urbanska K (ed) Differentiation patterns in higher plants. Academic Press, New York, pp 53–67Google Scholar
  11. Hamrick JL, Godt MJW (1990) Allozyme diversity in plant species. In: Brown AHD, Clegg MT, Kahler AL, Weir BS (eds) Plant population genetics, breeding and genetic resources. Sinauer Associates, Sunderland, Mass., pp 43–63Google Scholar
  12. Jain SK (1977) Genetic diversity of weedy rye populations in California. Crop Sci 17:480–482Google Scholar
  13. Khush GS (1962) Cytogenetic and evolutionary studies in Secale II. Interrelationships of the wild species. Evolution 16:484–496Google Scholar
  14. Khush GS (1963) Cytogenetic and evolutionary studies in Secale III. Cytogenetics of weedy ryes and origin of cultivated rye. Econ Bot 17:60–71Google Scholar
  15. Khush GS, Stebbins GL (1961) Cytogenetic and evolutionary studies in Secale I. Some new data on the ancestry of S. cereale. Am J Bot 48:723–730Google Scholar
  16. Lundqvist A (1956) Self-incompatibility in rye. Hereditas 42:293–348Google Scholar
  17. Maruyama T (1970) Effective number of alleles in a subdivided population. Theor Popul Biol 1:273–306Google Scholar
  18. Maruyama T (1972) Distribution of gene frequencies in a geographically structured finite population. I. Distribution of neutral genes and of genes with small effect. Ann Hum Genet 35:411–423Google Scholar
  19. Nagylaki T (1975) Conditions for the existence of clines. Genetics 80:595–615Google Scholar
  20. Nei M (1972) Genetic distance between populations. Am Nat 106:283–292CrossRefGoogle Scholar
  21. Nei M (1973) Analysis of genetic diversity in subdivided populations. Proc Natl Acad Sci USA 70:3321–3323Google Scholar
  22. Nei M, Maruyama T, Chakraborty R (1975) The bottleneck effect and genetic variability in populations. Evolution 29:1–10Google Scholar
  23. Perez de la Vega M, Allard RW (1984) Mating system and genetic polymorphism in populations of Secale cereale and S. vavilovii. Can J Genet Cytol 26:308–317Google Scholar
  24. Ritland K, Jain SK (1981) A model for the estimation of outcrossing rate and gene frequencies based on n independent loci. Heredity 47:37–54Google Scholar
  25. Schmidt-Stohn G, Wricke G, Weber WE (1986) Estimation of selfing rates in self-fertile rye plants using isozyme marker loci. Z Pflanzenzucht 96:181–184Google Scholar
  26. Shields CR, Orton TJ, Stuber CW (1983) An outline of general resource needs and procedures for the electrophoretic separation of active enzymes for plant tissue. In: Tanksley SD, Orton TJ (eds) Isozymes in plant genetics and breeding, part A. Elsevier Science Publ, Amsterdam, pp 443–468Google Scholar
  27. Slatkin M (1981) Estimating levels of gene flow in natural populations. Genetics 99:323–335Google Scholar
  28. Slatkin M (1985) Rare alleles as indicators of gene flow. Evolution 39:53–65Google Scholar
  29. Slatkin M, Barton NH (1989) A comparison of three indirect methods for estimating average levels of gene flow. Evolution 43:1349–1368Google Scholar
  30. Sneath PHA, Sokal RR (1973) Numerical taxonomy. W.H. Freeman & Co, San FranciscoGoogle Scholar
  31. Stebbins GL (1957) Self fertilization and population variability in the higher plants. Am Nat 9:337–354Google Scholar
  32. Stutz HC (1972) On the origin of cultivated rye. Am J Bot 59:59–70Google Scholar
  33. Sun M, Ganders FR (1990) Outcrossing rates and allozyme variation in rayed and rayless morphs of Bidens pilosa. Heredity 64:139–143Google Scholar
  34. Suneson CA, Rachie KO, Khush GS (1969) A dynamic population of weedy rye. Crop Sci 9:121–124Google Scholar
  35. Vaquero F, Vences FJ, Garcia P, Ramirez L, Perez de la Vega M (1989) Mating system in rye: variability in relation to the population and plant density. Heredity 62:17–26Google Scholar
  36. Vences FJ, Vaquero F, Garcia P, Perez de la Vega M (1987a) Further studies on phylogenetic relationships in Secale: on the origin of its species. Plant Breed 98:281–291Google Scholar
  37. Vences FJ, Vaquero F, Perez de la Vega M (1987b) Phylogenetic relationships in Secale (Poaceae): an isozymatic study. Plant Syst Evol 157:33–47Google Scholar
  38. Wricke G (1979) Degree of self-fertilization under free pollination in rye populations containing a self-fertility gene. Z Pflanzenzucht 82:281–285Google Scholar
  39. Wright S (1931) Evolution in Mendelian population. Genetics 16:97–159Google Scholar
  40. Wright S (1951) The genetical structure of populations. Ann Eugen 15:323–354Google Scholar
  41. Wright S (1969) Evolution and the genetics of populations. Vol. 2. The theory of gene frequencies. University of Chicago Press, ChicagoGoogle Scholar
  42. Zohary D (1971) Origin of South-West Asiatic cereals: wheats, barley, oats and rye. In: Davis PH et al. (eds) Plant life of South-West Asia. Bot Soc Edinburgh, pp 235–263Google Scholar

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • M. Sun
    • 1
  • H. Corke
    • 1
  1. 1.Department of Agronomy and Range ScienceUniversity of CaliforniaDavisUSA
  2. 2.Department of BotanyUniversity of Hong KongHong Kong

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