Genetic diversity and population structure of feral rapeseed (Brassica napus L.) in Japan

Autoři: Ruikun Chen aff001;  Ayako Shimono aff002;  Mitsuko Aono aff003;  Nobuyoshi Nakajima aff003;  Ryo Ohsawa aff004;  Yosuke Yoshioka aff004
Působiště autorů: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan aff001;  Faculty of Science, Toho University, Funabashi, Chiba, Japan aff002;  Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan aff003;  Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan aff004
Vyšlo v časopise: PLoS ONE 15(1)
Kategorie: Research Article
doi: 10.1371/journal.pone.0227990


Rapeseed (Brassica napus L.) is one of the most economically important oilseed crops worldwide. In Japan, it has been cultivated for more than a century and has formed many feral populations. The aim of this study was to elucidate the genetic diversity of feral rapeseeds by genotyping 537 individuals (among which 130 were determined to be genetically modified) sampled from various regions in Japan. Analysis of 30 microsatellite markers amplified 334 alleles and indicated moderate genetic diversity and high inbreeding (expected heterozygosity, 0.50; observed heterozygosity, 0.16; inbreeding coefficient within individuals, 0.68) within the feral populations. The Mantel test showed only an insignificant weak positive correlation between geographic distance and genetic distance. Analysis of molecular variance showed a greater genetic diversity among individuals than between populations. These results are in accordance with population structure assessed by using principal coordinate analysis and the program STRUCTURE, which showed that the 537 individuals could be assigned to 8 genetic clusters with very large genetic differences among individuals within the same geographic population, and that among feral individuals, many are closely related to rapeseed accessions in the NARO Genebank but some have unknown origins. These unique feral rapeseeds are likely to be affected by strong selection pressure. The results for genetically modified individuals also suggest that they have two different sources and have a considerable degree of diversity, which might be explained by hybridization with nearby individuals and separation of hybrid cultivars. The information obtained in this study could help improve the management of feral rapeseed plants in Japan.

Klíčová slova:

Alleles – Heterozygosity – Inbreeding – Japan – Phylogeography – Population genetics – Rapeseed – Species diversity


1. Statistics of Japan. [Internet]. Crop survey (paddy/land rice, wheat, beans, sweet potato, forage crops, crafts crops). c2008- [cited 29 Nov 2019]. Available from: Japanese.

2. United States Department of Agriculture. [Internet] In: Oilseeds: World Markets and Trade; c2017 [cited 1 Dec 2018]. Available from:

3. Shiga T. Rape breeding by interspecific crossing between Brassica napas and Brassica campestris in Japan. Jpn. Agric. Res. Q. 1970;5:5–10.

4. Hoshikawa K. [The Origin and Diffusion of Domesticated Plants]. Ninomiya Shoten Publishers (Tokyo). 1987. pp. 311. Japanese.

5. Nishizawa T, Tamaoki M, Aono M, Kubo A, Saji H, Nakajima N. Rapeseed species and environmental concerns related to loss of seeds of genetically modified oilseed rape in Japan. GM crops. 2010;1(3):143–156. doi: 10.4161/gmcr.1.3.12761 21844669

6. The Ministry of Agriculture, Forestry and Fisheries of Japan. [Internet] [Circumstances surrounding the buckwheat and rapeseed]. [cited 1 Dec 2018]. Available from: Japanese.

7. Saji H, Nakajima N, Aono M, Tamaoki M, Kubo A, Wakiyama S, et al. Monitoring the escape of transgenic oilseed rape around Japanese ports and roadsides. Environ Biosafety Res. 2005;4(4):217–222. doi: 10.1051/ebr:2006003 16827549

8. Pivard S, Adamczyk K, Lecomte J, Lavigne C, Bouvier A, Deville A, et al. Where do the feral oilseed rape populations come from? A large-scale study of their possible origin in a farmland area. J Appl Ecol. 2008;45(2):476–485.

9. Elling B, Neuffer B, Bleeker W. Sources of genetic diversity in feral oilseed rape (Brassica napus) populations. Basic Appl Ecol. 2009;10(6):544–553.

10. Aono M, Wakiyama S, Nagatsu M, Kaneko Y, Nishizawa T, et al. Seeds of a possible natural hybrid between herbicide-resistant Brassica napus and Brassica rapa detected on a riverbank in Japan. GM crops. 2011;2(3):201–210. doi: 10.4161/gmcr.2.3.18931 22179196

11. Crawley MJ, Brown SL. Seed limitation and the dynamics of feral oilseed rape on the M25 motorway. Proceedings of the Royal Society of London B. Biol. Sc. 1995;259(1354):49–54.

12. Mizuguti A, Yoshimura Y, Shibaike H, Matsuo K. Persistence of feral populations of Brassica napus originated from spilled seeds around the Kashima seaport in Japan. Jpn. Agric. Res. Q. 2011;45(2):181–185.

13. Canola Council of Canada. [Internet] Canola Variety Selection Guide; c2019 [cited 1 Dec 2018]. Available from:

14. Ministry of Finance Japan. [Internet] Trade Statistics of Japan. [cited 1 Dec 2018]. Available from:,2,,,,,,,,4,1,2014,0,0,0,2,120510000,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,20. In Japanese.

15. Katsuta K, Matsuo K, Yoshimura Y, Ohsawa R. Long-term monitoring of feral genetically modified herbicide-tolerant Brassica napus populations around unloading Japanese ports. Breed Sci. 2005;65(3):265–275.

16. The Ministry of Agriculture, Forestry and Fisheries of Japan. [Internet] [Result of 'Survey on genetically modified plants in 2014']. [cited 1 Dec 2018]. Available from:

17. Chen RK, Hara T, Ohsawa R, Yoshioka Y. Analysis of genetic diversity of rapeseed genetic resources in Japan and core collection construction. Breed Sci. 2017; 16192.

18. Shimizu T, Yano K. A post-labeling method for multiplexed and multicolored genotyping analysis of SSR, indel and SNP markers in single tube with bar-coded split tag (BStag). BMC Res Notes 2011;4(1):161.

19. Nei M, Tajima F, Tateno Y. Accuracy of estimated phylogenetic trees from molecular data. J. Mol. Evol. 1983;19(2):153–170. doi: 10.1007/bf02300753 6571220

20. Liu K, Muse SV. PowerMarker: an integrated analysis environment for genetic marker analysis. Bioinformatics. 2005;21(9):2128–2129. doi: 10.1093/bioinformatics/bti282 15705655

21. Peakall R, Smouse PE. GenAlEx 6.5: genetic analysis in Excel. Population genetic software for teaching and research-an update. Bioinformatics. 2012;28:2537–2539. doi: 10.1093/bioinformatics/bts460 22820204

22. Excoffier L, Lischer HE. Arlequin suite ver 3.5: a new series of programs to perform population genetics analyses under Linux and Windows. Molecular ecology resources. 2010;10(3):564–567. doi: 10.1111/j.1755-0998.2010.02847.x 21565059

23. Pritchard JK, Stephens M, Donnelly P. Inference of population structure using multilocus genotype data. Genetics. 2000;155(2):945–959. 10835412

24. Earl DA. STRUCTURE HARVESTER: a website and program for visualizing STRUCTURE output and implementing the Evanno method. Conserv Genet Resour. 2012;4(2):359–361.

25. Evanno G, Regnaut S, Goudet J. Detecting the number of clusters of individuals using the software STRUCTURE: a simulation study. Mol Ecol. 2005;14(8):2611–2620. doi: 10.1111/j.1365-294X.2005.02553.x 15969739

26. Liu YB, Wei W, Ma KP, Darmency H. Backcrosses to Brassica napus of hybrids between B. juncea and B. napus as a source of herbicide-resistant volunteer-like feral populations. Plant Sci. 2010;179(5):459–465. doi: 10.1016/j.plantsci.2010.07.005 21802604

27. Pascher K, Macalka S, Rau D, Gollmann G, Reiner H, Glössl J, et al. Molecular differentiation of commercial varieties and feral populations of oilseed rape (Brassica napus L.). BMC Evol. Biol. 2010;10(1):63.

28. Weir BS, Cockerham CC. Estimating F-statistics for the analysis of population structure. Evolution. 1984;38(6):1358–1370. doi: 10.1111/j.1558-5646.1984.tb05657.x 28563791

29. Frankham R, Ballou JD, Briscoe D. Introduction to conservation genetics. Cambridge: Cambridge University Press; 2010. p. 309–336.

30. Bond JM, Mogg RJ, Squire GR, Johnstone C. Microsatellite amplification in Brassica napus cultivars: cultivar variability and relationship to a long-term feral population. Euphytica. 2004;139(2):173–178.

31. Andow DA, Zwahlen C. Assessing environmental risks of transgenic plants. Ecol Lett. 2006;9(2):196–214. doi: 10.1111/j.1461-0248.2005.00846.x 16958885

32. Snow AA, Andow DA, Gepts P, Hallerman EM, Power A, Tiedjeet JM, et al. Genetically engineered organisms and the environment: current status and recommendations. Ecol Appl. 2005;15(2):377–404.

33. Government of Canada. [Internet] ARCHIVED—Glyphosate Tolerant Canola, GT73. [cited 1 Dec 2018]. Available from:

34. Malla S, Brewin D. The value of a new biotechnology considering R&D investment and regulatory issues. AgBioForum. 2015;18(1):7–25.

35. Morrison MJ, Harker KN, Blackshaw RE, Holzapfel CJ, O’Donovan JT. Canola yield improvement on the Canadian Prairies from 2000 to 2013. Crop Pasture Sci. 2016;67(4):245–252.

36. Salisbury PA, Cowling WA, Potter TD. Continuing innovation in Australian canola breeding. Crop Pasture Sci. 2016;67(4):266–272.

37. Warwick SI, Legere A, Simard MJ, James T. Do escaped transgenes persist in nature? The case of an herbicide resistance transgene in a weedy Brassica rapa population. Mol Ecol. 2008;17(5):1387–1395. doi: 10.1111/j.1365-294X.2007.03567.x 17971090

38. Pandolfo CE, Presotto A, Carbonell FT, Ureta S, Poverene M, Cantamutto M. Transgene escape and persistence in an agroecosystem: the case of glyphosate-resistant Brassica rapa L. in central Argentina. Environ Sci Pollut Res Int. 2018;25(7):6251–6264. doi: 10.1007/s11356-017-0726-3 29243152

39. Gilbert N. GM crop escapes into the American wild. Nature News 2010. [cited 1 Dec 2018]. doi: 10.1038/news.2010.393

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