1. Development, Role and Scope of Transgenic Herbicide Resistant Crops
Credit Seminar On
Development, Role and Scope of Transgenic Herbicide Resistant Crops
Department of Agronomy
Bihar Agricultural University, Sabour Bhagalpur
Presented by:
DURGESH SINGH
BAC/D/AGRO/003/

2. Introduction of THRC’s
1984, Commercially introduced in Canada through atrazine resistant canola.
1995, Monsanto introduced Roundup ready soybean.
1996. GM foods were first put on the market in USA,
71% of the of GM (genetically modified) plants were herbicide resistant. (BARBER 1999).
102 m ha Global biotech crop area.
10.3 m small and large farmers in 22 countries planted GM crops.
Conti…..

3. Cotton and rapeseed varieties are resistant to three herbicides- glyphosate, sulfonylurea and bromoxynil, in USA (DOWNEY 1999).
There are 22 transgenic crops approved for commercial use in the world till March 2008.
In the world, herbicide resistant corn, oilseed rape, soybean and cotton have been commercialized from many years.
but in India only cotton crop is allowed for cultivation.

4. Annual losses caused by different pests in India
Pest Loss in value per year
Rs. in crores Loss (%)
Weeds
1980 33
Insects
1300 26
Diseases
1000 20
Storage pest
390 8
Rodents
300 6
Other pests 7
Total
Source: Vision 2050 (NRCWS Perspective plan 2014)

5. Average reduction in yields of important crops due to weeds in India
Rice
a) Transplanted
15-35
b) Direct seeded
30-65
c) Upland
45-90
Wheat
6-35
Maize
30-50
Millets
11-56
Sesamum
17-40
Mustard & Rapeseed 30
Groundnut
18-52
Sugarcane
15-72
Jute
56-58
Cotton
47.5
Source: DRR (2011)

6. Global and Indian pesticides use scenario (% of total)
Global scenario of pesticide use
Indian scenario of pesticide use
Source: Vision 2050 (NRCWS Perspective plan 2014)

7. Source: Yaduraju (2012)

8. Why THRC’s ?

9. Crop Injury Symptom
Maize crop
Wheat crop

10. Wheat Crop injury by 2,4-D late application
Injury: spike distortion, spike malformation
Source :

11. Maize Crop injury by 2,4-D late application
Injury: Rolled "buggy-whip" Whorl
Source :

12. Soybean crop injury by Atrazine, Metribuzin herbicide
Injury: Lower leaves show chlorotic to necrotic and in severe cases, complete death of plant
Source:

13. What is THRC’s ?
Process of transferring gene from one living organisms to another to serve specific purposes is called Genetic engineering
The crops produced by this process is called transgenic crops.
If gene transfer into the crop is responsible for the herbicide resistant then crops are called THRC’s
Herbicide resistant refers to the inherited ability of weeds or modified ability of a crop.

14. Important Countries and their area (m ha ) of biotech crops in 2006.
Rank
Country
Area
(m ha)
Biotech Crops 1
USA
54.6
Soybean, Maize, cotton, canola, alfalfa 2
Argentina
18.0
Soybean, Maize, cotton 3
Brazil
11.5
Soybean, cotton 4
Canada
6.1
Soybean, Maize, canola 5
India
3.8
Cotton 6
China
3.5
cotton 7
Paraguay
2.0
Soybean
Source: James (2006)

16. Share of different cultivated THRC’s (%)

17. Herbicide –resistant crops in the world (Das, 2015)SN
HRC’s
Herbicides resisted
Trademark designation
Commercial status (years) 1
Canola
Bromoxynil
Glufosinate-AM
Glyphosate
BXN CANOLA
LIBERTY LINK CANOLA
ROUNDUP READY RAPE
Europe 1995
Canada &Europe 1995
Canada 1997 &Europe 1998 2
Corn
Imidazolinones
Sethoxydim
LIBERTY LINK CORN
ROUNDUP READY CORN
IMI CORN
SR CORN
USA 1997
USA & Canada 1998
USA & Brazil 1997 3
Cotton
Sulfonylureas
BXN COTTON
LIBERTY LINK COTTON
ROUNDUP READY COTTON
19-51A COTTON
USA 2000 4
Rice
LIBERTY LINK RICE
USA & Asia 5
Soybean
LIBERTY LINK SOYBEAN
ROUNDUP READY SOYBEAN
STS SOYBEAN
USA1998 & Brazil 1998
USA 1993 6
Tobacco
Chlorsulfuron
Asulam
BXN TOBACCO
CHLORSULFURON RES TOBACCO
ASULAM RESISTANT TOBACCO
Europe 7
Sugerbeet
LIBERTY LINK SUGERBEET ROUNDUP READY SUGERBEET
Europe 8
Rapeseed
GLYPHOSATE RES RAPESEED - 9
Tomato
GLYPHOSATE RES TOMATO

18. Herbicides tolerant GM crops/plants at present
Soybeans
Glyphosate, Glufosinate-ammonium
Maize
Glyphosate, Imazethapyr, Sethoxydim, Glufosinate ammonium
Alfalfa
Glyphosate
Cotton
Triasulfuron, Metsulfuron-methyl, Glyphosate, Glufosinate ammonium
Canola
Glyphosate, Glufosinate ammonium, Imazethapyr, Bromoxynil, ioxynil
Rice
Imazethapyr, Glufosinate ammonium
Wheat
Glyphosate, Imazethapyr, Cyanamid AC299263
Tobacco
Bromoxynil, ioxynil
Sugarbeet
Sunflower
Imazethapyr [

19. Species resistant to Glycines herbicides by
top 10 crops
Source: Heap (2013)

20. Herbicide resistant crops developed by plant transformation
Source of resistant-
gene
Mode of resistance
Transfer in plants
Glyphosate
Escherichia coli over expression
Altered EPSPS
Tobacco
Agrobacterium
tumefaciens
Over expression
tumefaciens of EPSPS
Glufosinate
Streptomyces hygroscopiues
Expression of PAT
Soybean, Rapeseed
Chlorsulfuron
Nicotiana tabacum
ALS mutated gene
Tobacco, Tomato, Potato, Maize
Bromaxynil
Klebsiella ozene
Nitrilase
Tobacco, Rice
Norflurazon
Erwinia uredovora
Enhanced carotenoid biosynthesis
Cotton, Clover, Rapeseed
Dalapon
Pseudomonas putid
Dehalogenase
2,4-D
Alcaligene eutrophus
Monoxygenase
Tobacco, Cotton
Phenmediphem
Arthrobactor oxidens
Carbonate hydroxylase
Source: Kandasamy et al., (2002)

21. Types of Herbicide resistance
Exclusionary resistance mechanisms
Herbicide uptake- reduce leaf area, waxy surface
Translocation- Lolium rigidum show reduce translocation
Compartmentation- storing, accumulation or sequestration of herbicide, Lolium rigidum in Australiya
Metabolic degradation- E. colona to propanil by arylacylamidase, Abutilon to atrazine by glutathione-s-transferase enzyme.
Target site mechanisms of Resistance
Altered molecular/cellular target of herbicide action- Lactuca sativa to sulfonylurease
Site of action overproduction- Alopecurus myosuroides due to increase activity of glutathione-s-transferase (GST)

22. How transgenic plants are made?

23. Identification of useful gene
The cloning of the gene into a suitable plasmid vector
Delivery of the vector into plant cell.

24. Development of Herbicide-Resistant crops
Traditional selective plant breeding
Biotechnological techniques
In vitro mutant
Selection at the cell or tissue
level
Somatic
Hybridization
Microspore
(gametophytic)
And seed
mutagenesis
Plant transformation
(transfer of cloned
Genes into susceptible
Plants)

25. – The promoter - an on/off switch
A gene construct consists typically of three elements:
– The promoter - an on/off switch
– The transgene - encodes selected trait
– The terminator - stop signal
In addition Marker genes for distinguishing GM from non-GM cells during crop development may also be present

28. Herbicide-resistant soybeans have been quickly adopted
Herbicide-resistant soybeans have been quickly adopted. In 2010, 93% of all soybeans grown in the USA were herbicide-resistant, as were 78% of all cotton and 70% of all maize varieties

29. Example of herbicide resistance
 1. Glyphosate-
Glyphosate is the broad spectrum herbicide that inhibit the enzyme
5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). This enzyme involved in biosynthesis of aromatic amino acids in plants.  
A. Production of an enzyme that inactivates glyphosate.
B. Over production of EPSPS enzyme.
C. Encode an EPSPS enzyme that is tolerant to glyphosate.
2. Mutants of Salmonella typhimurium and E. coli expressed tolerance to glyphosate e.g. tobacco, soybean.
3. Petunia hybrida (flowering plant of S. America) EPSPS has been over expressed in other crops.

31. Shikimic acid pathway
Glyphosate works by blocking the plants' ability to produce certain proteins and it disrupts amino acid synthesis. It blocks the shikimic acid pathway.

33. Adoption rate of glyphosate-resistant crops in the United States.
Source: USDA ERS (2009)

34. Role of THRC’s

35. Role……. To adopt minimum- or no-tillage systems.
We can replaced previously used herbicides with glyphosate.
In soybean and canola crops provides superior weed management.
Manufacturers of other herbicides for cotton and soybean have countered with reductions in prices for their products.
(Nelson and Bullock, 2003)
Make crops resistant to most herbicide classes.
(Gressel, 2002).
Glyphosate is rapidly degraded by soil microbes.
(Duke et al., 2003).
No effect of glyphosate on microflora of soils in Argentina at twice the recommended rates of the herbicide.
(Gomez and Sagardoy, 1985)

36. Role……. Adoption of GR soybean and no-till seeding in Argentina.
Source: Trigo and Cap (2006)

37. Role…….
Number of different herbicide active ingredients and herbicide sites of action used on at least 10% of hectares from 1995 to 2005 in soybean in the United states.
Source: Wilcut (2009)

38. Role…….
US tillage practices in glyphosate-resistant (GR) and non-GR cotton from as a percentage of hectares planted Source: Dill et al., (2008)

39. Role…….
US tillage practices in glyphosate-resistant (GR) and non-GR soybean from as a percentage of hectares planted. Source: Dill et al., (2008)

40. Income benefit from transgenic crops from
1996 to 2007
Crop
Income
(US $/ha)
Yield
(million tons)
Herbicide-resistant soybean
21.8
67.8
Herbicide and insect-resistant corn
8.1
15.1
Herbicide and insect-resistant cotton
13.4
6.9
Herbicide-resistant canola
1.4
4.4
Source: Brookes and Barfoot (2011)

41. Environmental impact of the change of herbicide use in herbicide resistant crops globally from 1996 to 2009
Crop
Change in herbicide use (million kg)
Change in herbicide use on HR crops (%)
Change in Environmental Impact (%)
HR soybean
-40.9
-2.2
-16.0
HR corn
-140.3
-9.2
-10.5
HR cotton
-8.9
-4.0
-6.9
HR canola
-14.0
-16.2
-23.2
Source: Brookes and Barfoot (2011)

42. Comparison of impacts of typical herbicide regimes for conventional, compared with glyphosate-resistant sugarbeet in the UK and Germany in terms of energy requirements (MJ), global arming potential [kg carbon dioxide (CO2) equivalent], and ozone depletion [kg chlorofluorocarbon (CFC) 11 equivalent] per functional unit Source: Bennett et al., (2004)

43. Scope of THRC’s

44. Scope of THRC’s in abroad
Corn:-
Over-the-top application of liberty (glufosinate) herbicide.
2. It also allows post-emergence application of Roundup (glyphosate) and some other glyphosate-type products directly to corn.
This system should provide broad spectrum annual and perennial weed control in corn.
Conti…..

45. Liberty link soybean:
Allow over-the-top application of Liberty (glufosinate) herbicide.
Roundup ready soybean:
It allows over-the-top application of Roundup Ultra (glyphosate) and some other glyphosate containing products to soybean from cracking to flowering.
The programme allows broad-spectrum control of many annual and perennial grasses and broadleaf weeds in soybean crop.
Conti….

46. Acetohydroxy acid synthase show multiple resistant can use in crops for utilizing this characters.
Gene encoding a chimeric protein of rat cytochrome P4507A1 and yeast NADPH-cytochromeP450 oxidoreductase genes for glutathione reductase and superoxide dismutase.

47. Results of animal feeding studies with GRCs.
Crop
Animal
Result
Reference
Maize
Rat
No effect
Hammond et al., 2004
Swine
Hyun et al., 2004
Cattle
Erickson et al., 2003
Dairy cattle
Donkin et al., 2003
Poultry
Sidhu et al., 2000
Soybean
Zhu et al., 2004
Mice
Brake and Evenson, 2004
Cromwell et al., 2002
Hammond et al., 1996
Canola
Taylor et al., 2004
Sugarbeet
Sheep
Hartnell et al., 2005

48. Scope of THRC’s in India
The only genetically modified cash crop under commercial cultivation in India is cotton.
Bt Cotton:
Bt cotton was first used in India in 2002 and now Bt cotton is grown over 11.6 million hectares. Production of cotton is increased fron kg/ha from 2002 – 2014.
GM-mustard:
Dhara Mustard Hybrid-11 or DMH-11 is a GM variety of mustard developed by the Delhi University’s Centre for Genetic Manipulation of Crop Plants. If approved by the Centre, this will be the second GM crop, after Bt Cotton, and the first transgenic food crop to be allowed for cultivation in the country.
We can go for other crops after research like- Maize, Rice, Wheat, Soybean, Tobacco etc.

49. Effect of THRC’s on productivity of cotton in India

50. Total Cotton production of India from 2002 to 2017

51. Effect of T.H.R. cotton on Farmers of India
Source: Hunter (2014)

52. Why Multinational companies more entrusted in HRCs ?
Designing a new herbicide based on selectivity to each crop has not been much successful in the past.
More economical than develop a new herbicide.
Take less time and more success in genetic engineering.
Marketing HRCs is more profit-driven since the concerned MNC will sell seed and herbicide both.
Less risky and economical.
Marketing is less competitive because it remain exclusive business of MNC, who develop it.

53. Advantages of HRCs towards Weed control
Encourage the safe use of non selective herbicide.
To control parasitic weeds selectively
To control weeds closely related to crops.
Reduce consumption of herbicide.
More simplicity and flexibility in the time of application.
Efficient weeds control provide higher yield.
Reduce total cultivation cost due to less traffic, less spraying- soybean brought down cost of conventional herbicides from US $ 40 to $ 60 per acre to $ 20 to $ 30 per acre (Indian Rs to 5000).
Useful where pre emergence application is not possible due to rain.
Other toxic and residual herbicide can be banned after HRCs adopted.
Use of herbicides that are more environment friendly- Glyphosate and Gluphosinate are absorb by organic matter and decomposed readily.

54. Limitations of biotech crops (HRCs)
Adopting HRCs will leads to increase dependence on single herbicide or family.
It influence the genetic purity of crops.
May cause gene pollution and chance to develop “super weeds”.
Crop seed or propagules left in the field results resistant volunteer crops.
Safety of GMC food is also great concern among the people.
Contamination of food.
Long time use cause limit the bio-diversity.
Continuous use of same herbicide may develop resistant in weeds
Abandonment of IWM in course of time.
Possible sift in weed spp./insect pest.

55. Conclusion

56. Thank you

57. References
Anonymous (1998), Kompendium Gentechnologie und Lebensmittel. AgrEvo GmbH, Bund für Lebensmittelrecht und Lebensmittelkunde e.V. (BLL), Monsanto (Deutchland) GmbH, Novartis (Deutschland) überarbeitet von Genius GmbH – Institut für Biochemie. TU Darmstadt.
Barber S. (1999), Transgenic plants: field testing and commercialisation including a consideration of novel herbicide resistant oilseed rape (Brassica napus L.). In: British Crop Protection Council (ed.) Proceedings No. 72, Gene Flow and Agriculture: Relevance for transgenic crops:3-12.
Clive James (2006); (feb, 2008).
Downey RK. (1999), Gene flow and rape – the Canadian experience. In: British Crop Protection Council (ed.) Proceedings No. 72, Gene Flow and Agriculture: Relevance for transgenic crops:
Freier B, Triltsch H, Gosselke U. (1999), Die Dimension der natürlichen Kontrolle von Getreideblattläusen durch Prädatoren. Gesunde Pflanzen 51(3):65-71
James C, Krattiger AF. (1996), Global Review of the Field Testing and Commercialisation of Transgenic Plants: The first Decade of Crop Biotechnology. ISAAA Briefs No pp., Ithaca, N.Y.
Stephen O. Duke, Stephen B. Powles, (2009), Glyphosate-Resistant Crops and Weeds: Now and in the Future, Ag Bio Forum, 12(3&4):
T.K.Das, (2015), weed science basics and applications, pp
USDA-APHIS (1999), Historical Database.

58. Any Question ?

59. Conclusion
Transgenic Herbicide resistant crops have a great potential in the simplification of weed management. Handled judiciously, these crops may be beneficial by allowing effective, efficient and later weed control, enabling no-till systems, reducing erosion and cast of cultivation. As environment point of view, it reduces pollution, energy used during cultivation, global warming and ozone depletion. However, it must be emphasised that the risk from THRCs should be carefully evaluated prior to releasing the THRC into a cropping system. For long-term benefits of HRC, and avoiding concerns/risks, these must be used as component of IWM and not in isolation, and overuse, abuse or misuse should be avoided.