Genetic pollution

Cause, mechanisms, limitation, sources

1. 1 29 July 2021 Genetics & Plant Breeding

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3. Manoj C A PHD16AGR6022 Genetic Pollution – “a multiplying nightmare”!!

4. Timeline Introduction Mechanisms Factors determining the processes Possibilities of Gene Flow Scientific stories Conclusion Potential sources for the cause 29 July 2021 4 Genetics & Plant Breeding

5. Genetic pollution 5 INTRODUCTION Genetic pollution is a controversial  term for uncontrolled gene flow into wild populations. "Uncontrolled spread of genetic information (frequently referring to transgenes) into the genomes of organisms in which such genes are not present in nature” 29 July 2021 Genetics & Plant Breeding

6. Genetic pollution 6 Genetic deterioration Genetic swamping Genetic takeover Genetic aggression Gene flow 29 July 2021 Genetics & Plant Breeding

7. Feral species Invasive species Domestic species Gene Flow 29 July 2021 7 Genetics & Plant Breeding

8. Mechanisms Wild, related flora growing nearby are pollinated by a GE crop Non-GE or organic crops in neighbouring fields are pollinated by the GE crop A semi-wild, weed or ‘feral’ population of GE plants develops if the GE crop survives in the agricultural or natural environment Micro-organisms in the soil or the intestines of animals eating the GE crop acquire the foreign genes. 29 July 2021 8 Genetics & Plant Breeding

9. Possibilities 1) Genetically modified might lead the non-GM organisms to extinction . 2) Their genetics will change and they will not be able to show their characteristics. 3) There are chances that these organisms might develop resistance against pesticides or herbicides and it will be a nightmare for the farmers. 29 July 2021 9 Genetics & Plant Breeding

10. American bison X 29 July 2021 10 Genetics & Plant Breeding

11. The story of Tara 29 July 2021 11 Genetics & Plant Breeding

12. Factors determining gene flow Pre-zygotic barriers to hybridization 1. Spatial isolation of parent populations 2. Synchrony in flowering 3. Direction of the cross (the parent from which the pollen and ovules originate) 4. Method of pollen dissemination and presence of pollen vectors 5. Pollen competition from maternal population 6. Environmental conditions 29 July 2021 12 Genetics & Plant Breeding

13. Post-zygotic barriers to hybridization Mitotic compatibility of the two parental genomes Ability of endosperm to support hybrid embryo development Number and viability of hybrid seeds Establishment of hybrid plants Seed dormancy Growth vigor of hybrid plant Competition from other plants Influence of pests, diseases, predators 29 July 2021 13 Genetics & Plant Breeding

14. Propagation of hybrid plants Pollen and ovule fertility (meiotic stability and chromosome pairing) Ability to produce sexual progeny (selfed and backcrossed) Ability to survive over subsequent generations Seed number, viability and dormancy Habitat conditions, plant competition, pests, diseases and predators. 29 July 2021 14 Genetics & Plant Breeding

15. Potential sources Invasive species Genetically modified organisms Deliberately introduced species Mutated organisms 29 July 2021 15 Genetics & Plant Breeding

16. 1. Invasive species Alter the genetic pool which is an irreversible change. Invade both large and small native populations and have a profound effect. Form sterile or more evolutionarily fit hybrids that can outcompete the native populations. Can cause extinctions of small populations on islands that are particularly vulnerable due to their smaller amounts of genetic diversity. 29 July 2021 16 Genetics & Plant Breeding

17. 29 July 2021 17 Genetics & Plant Breeding Cercocarpus traskiae Catalina Island

18. 2. Genetic Engineering Transgene escape Tracer markers 29 July 2021 18 Genetics & Plant Breeding

19. 3. Introduced species The introduction may or may not be intentional For aesthetic reason, hunting & sport and sometimes emotional Eg: Lantana, waterlilly 29 July 2021 19 Genetics & Plant Breeding

20. 4. Mutated organisms Mutants can then be bred with other mutants or individuals that are not mutated in order to maintain the mutant trait. Could have a negative impact on native populations as well. 29 July 2021 20 Genetics & Plant Breeding

21. Objective: To assess the extent of gene flow between cultivated rice and two of its close relatives under field conditions. 29 July 2021 21 Genetics & Plant Breeding

22. Materials and methods Sites: Korea and China Weedy rice ( O. sativa f. spontanea ) Wild rice ( O. rufipogon ) O. sativa - Minghui 63 F 5 line - Nam29/TR18 ( bar resistance gene) Herbicide resistance ( bar ) and SSR molecular fingerprinting 29 July 2021 22 Genetics & Plant Breeding

23. 29 July 2021 23 Genetics & Plant Breeding

24. Crop-weedy mixture @Korea 29 July 2021 24 Genetics & Plant Breeding

25. Crop-wild mixture @ China 29 July 2021 25 Genetics & Plant Breeding

26. Identification of interspecific hybrids 29 July 2021 26 Genetics & Plant Breeding

27. SSR (RM44) Amplification 29 July 2021 27 Genetics & Plant Breeding

28. Results 29 July 2021 28 Genetics & Plant Breeding

29. Rise of Superweeds Eg: Pigweed, Horseweed 29 July 2021 Genetics & Plant Breeding 29

30. Objectives: To assess the frequency of gene flow from transgenic plants to non-transgenic plants Evaluation of pollen dispersal and flight distance in open-field conditions To evaluate the influence of the wind on pollen dispersal and cross-pollination under field conditions. 29 July 2021 30 Genetics & Plant Breeding

31. Materials and methods Parents : Thaibonnet and Ariete Transgenic lines: T1506-5-6 and A2504-1-7 ( pat gene resistance to Amm . glufosinate ) Designs: side by side @ Italy circular design @ Spain 29 July 2021 31 Genetics & Plant Breeding

32. Field trails in Spain 29 July 2021 32 Genetics & Plant Breeding A B

33. Field plot in Italy 29 July 2021 33 Genetics & Plant Breeding

34. Before & after herbicide treatment 29 July 2021 34 Genetics & Plant Breeding

35. PCR Amplification Amplification of pat gene Amplification of Ariete glufosinate resistant plants Transgenic T506 plants Non transgenic lines Control Marker transgenic lines 29 July 2021 35 Genetics & Plant Breeding Progeny Non transgenic lines

36. Southern analysis of Thaibonnet field trail Digestion with Hind III Digestion with Eco RI 29 July 2021 36 Genetics & Plant Breeding

37. Results 29 July 2021 37 Genetics & Plant Breeding

38. Transgenic seedlings in circle 29 July 2021 38 Genetics & Plant Breeding

39. Circular distribution of PCR+ seedlings 29 July 2021 39 Genetics & Plant Breeding

40. Objectives: To assess gene flow within and between Acala and Pima cotton 29 July 2021 40 Genetics & Plant Breeding

41. Materials and methods Location: 15 commercial fields (14+1) in California Pima cotton: G. barbadense Acala cotton: G. hirsutum Transgenic varieties : Roundup Ready (RR) 29 July 2021 41 Genetics & Plant Breeding

42. 29 July 2021 42 Genetics & Plant Breeding

43. Spots on petal Pima Acala Hybrid 29 July 2021 43 Genetics & Plant Breeding

44. Results 29 July 2021 44 Genetics & Plant Breeding

45. Gene flow in small scale field trial within and among cotton species. 29 July 2021 45 Genetics & Plant Breeding

46. Gene flow in borders within and among cotton species 29 July 2021 46 Genetics & Plant Breeding

47. Preventative measures Specification Isolation distances Impact of new technologies on existing biodiversity Risk assessment through surveys Proper information dissemination Since 2005 there has existed a  GM Contamination Register , launched for that records all incidents of intentional or accidental release of organisms genetically modified using modern techniques 29 July 2021 47 Genetics & Plant Breeding

48. Monitoring groups 29 July 2021 Genetics & Plant Breeding 48

49. 49 29 July 2021 Genetics & Plant Breeding

50. 29 July 2021 Genetics & Plant Breeding 50 Thank you!!! Save PLAN(E)T