The document discusses various environmental challenges faced by agriculture over time and emerging solutions. It outlines how population growth put pressure on agriculture and led to unsustainability initially. Domestication of crops and animals around 10,000 years ago was an early solution. More recently, developments like the Haber process, green revolution varieties, and genetically modified crops have helped increase yields and avert potential food shortages. However, challenges remain due to factors like climate change, water scarcity, and increasing populations in developing countries.

1. Environmental challenges to Agriculture and the emerging solutions A.K. Joshi Department of Genetics & Plant Breeding Institute of Agricultural Sciences Banaras Hindu University

2. Environment & Agriculture Agriculture is strongly linked to environment and they both to human population Initially, challenges to agriculture increased since human population increased As population grew, cities emerged and pressure on agriculture increased further, causing “Non-sustainability”

3. Solutions emerged! First by domestication of crops (around 10,000 years ago) and then by management Domestication of cattle for cultivation: ~ 9000 years ago First plough: ~ 6000 years ago Horse collar: 3 rd century BC – In China 1701 AD: Jethrow Tull devised a simple seed drill – he was vilified A century later a threshing machine was greeted by riots

4. Also emerged threats! 1815: a gigantic volcanic eruption at Tambora in Indonesia led to the famous year “ Year without summer ”. Many countries frosted in summer. Wheat prices soared, and therefore, Thomas Robert Malthus (1798) forecasted a Population Crash , based on the calculation that “it was impossible to improve wheat yields as fast as people made babies”

5. More land under plough Malthusian crash was staved off in the 19 th century by bringing more land under plough – in N. America, Argentina and Australia But, famines became worse in Asia Then it was the Tractor (early 1800s) that averted Malthusian disaster – the first tractor had few advantages but they did not eat hay or oats . It released around 25% more land for crops

6. More land but less nutrients Again, Malthusian limit started approaching without sufficient nitrogen, phosphorus and potassium 1830 – a magic ingredient was discovered: Guano – In dry seabird islands of S. America and S. African coasts, immense deposits of bird droppings, rich in N & P, deposited over centuries

7. Guano Rush In 1843- a tiny island of Ichaboe (S.W. Africa) was discovered; covered in 25 feet of Penguin and gannet excrement It led to - “Guano Rush” followed by mutinies and battles During 1840-1880, guano nitrogen made a vast difference to European agriculture But soon the vast deposits were exhausted

8. Search for more nitrates In late 19 th century, the rich mineral nitrate deposits of Chile took the place of Guano. These nitrate mines fuelled Chilean economy and fertilized Europe’s farms On 2 nd July, 1909 - Carl Bosch (BASF) and Fritz Haber combined N (from air) with hydrogen (from coal) to make ammonia Then in few years, BASF started mining sky for nitrogen

9. Consequences Today, nearly half of the N atoms in the proteins of an average human beings came at some time or another through an ammonia factory Haber – nearly saved the German war effort as it was running out of nitrogen explosives in 1914, cut off from Chilean nitrates, but then went on to make lethal gas for chemical warfare and genocide

10. More N needed further technology Haber’s nitrogen was not welcome till middle of 20 th century Because it was a powder, and It was lodging the crop Then, dwarf varieties rescued the world as it made crops responsive to nitrogen More nitrogen = more food

11. Wheat drove the first major change India got 18000 tonnes of dwarf wheat from CIMMYT, Mexico in 1965 Sir N.E. Borlaug loaded 35 trucks in Mexico and sent to Los Angeles for transport to India And, thus introduced Green Revolution

12. Norin 10, the donor of the dwarfing gene which saved millions of lives

13. After 50 years of Green Revolution “w e need further efforts to feed the world, but the world is not the same”

14. Population increasing too much “more in developing countries” Sources: UN Population Division and Population Reference Bureau Developed 6.2 b 80%+ Developing

15. Most nations are short of money β -version of a high spatial resolution database of global income and poverty. Sub-national data compiled from country-level sources. Income was in many cases estimated from poverty incidence, and for countries with no data at all using regression models fitted with data from other countries in the region (see next slides). EU is income after taxes (and looks therefore too poor). R. Hijmans, IRRI; J. Dixon, CIMMYT

16. WDR: Three worlds of agriculture Urbanizing Agriculture based countries 82% of population in SSA Transforming countries 98% of population in SA 96% of EAP; 92% of MENA Urbanized countries 88% of population in ECA; 88% in LAC World Bank WDR, 2007

17. Environment is changing

18. e.g., Africa - Annual Precipitation Variation: 1988-98 (Hodson, CIMMYT) Variable Nature of Environments

19. A shift in thinking! No one understands better than farmers do how the weather change can affect people and their land But now, emerging weather patterns have made lot of other people worried, too, and their concerns are well founded (Yvo de Boer, Executive Sect. UN’s Framework Convention on Climate Change - UNFCCC)

20. Some environmental challenges – case study from India

21. Heat – a strategic issue for the S Asia Relative yield (+2 º C / current) for rice growing areas Also an issue for wheat and even maize, in different areas Change in yield (%) R. Hijmans, IRRI

22. Heat stressed areas are increasing For example: Environment for wheat in India Current 2050

23. Water scarcity Source: Ministry of Water Resources, Gov. India, 2006

24. Increasing Water Stress in Punjab Note: Figure in parentheses indicate stage of ground water use. A total of 137 blocks were assessed. Source: Planning Commission, 2007 J. Dixon, CIMMYT

25. Glaciers cover c.33,000 km 2 Provide c.8.6 X 10 6 m 3 of water / year 67% Retreating at a rapid rate Deglaciation – Simulated River Flows (next 10 decades)

26. Population changes Source: GPW. CIESIN/CIAT/FAO

27. Challenges for South Asia Over Exploitation of Groundwater Declining water tables 1-3m / year 67% of Glaciers in rapid retreat Medium-term increased river flows Threat of Glacier Lake Outburst Floods Longer-term (40 years+) reduced river flows Increasing Wheat Heat Stress 17-38% Reduction in High Potential Areas by 2020 Increasing Population

28. IMPACT OF CLIMATE CHANGE n.a. – not applicable for Alaska, Northern Canada and Antarctica Source: Cline 2007 Impact on agricultural production with carbon fertilization (%)

29. THE BIOFUEL BOOM Source: IFPRI IMPACT projections Changes in world prices of feedstock crops and sugar by 2020 under two scenarios compared to the baseline levels (%)

30. Source: IEA and APERC, 2005 Gasoline Demand from Transport (MTOE)‏ 0 50 100 150 200 250 300 350 400 450 2005 2010 2015 2020 2025 2030 million tons oil equivalent India Brazil USA EU China

31. Growth rates of yields for major cereals in developing countries are slowing Source: World Development Report 2008 SLOWING AGRICULTURAL PRODUCTIVITY GROWTH

32. Growth yield (% year) is decreasing: Wheat -2.0 -1.0 0.0 1.0 2 . 0 3.0 4.0 5.0 China India USA Russian Fed. France Canada Australia Germany Turkey Pakistan United Kingdom Argentina Iran Ukraine Kazakhstan Poland Italy Egypt Romania Spain Growth yield (%/year) 1966-79 1980-94

33. Solutions on the way?

34. Saving land through High-Yielding varieties Example: wheat in India 100 60 40 20 0 1961 1965 1970 1975 1980 1985 1990 1995 2000 Million hectares Land Used Land Saved 80 1961 2000 Production, 11 76 Million tonnes Av. Yield. t/ha 0.85 2.90 Population, Millions 452 1,016 Source: FAOSTAT, 2002

35. Higher yield with improved adaptation Hybrids in different crops: Vegetables, food crops (maize, sorghum, bajra) and also in self pollinated crops like Rice Hybrid rice has sustained cereal production in China and South East Asia Eastern Gangetic plains of India is the fastest adopter of hybrid rice in India Yield is around 40% higher; days to maturity lesser by around 30 days; required less water; good for enhancing cropping intensity

36. Varieties with superior stress tolerance are becoming available Flooding tolerance in rice (IRRI) Water-logging tolerance in pigeon pea (ICRISAT) Drought tolerance in rice (IRRI), wheat & maize (CIMMYT), barley (ICARDA), groundnut, sorghum & pearl millet (ICRISAT), beans (CIAT), & cowpea (IITA)

37. Stay green plants; more heat and drought tolerance

38. T. durum T. tauschii ABD Synthetic wheat developed by CIMMYT is already highlighted globally New hope for stress areas, mainly drought D + AB Synthetic wheat

39. Conservation Agriculture Saving environment and money and making agriculture sustainable

40. Transgenics!

41. Bt Cotton 20 million ha around the world 6 million ha in India 50,000 mt reduction in insecticide use Less health hazard Significant increases in farmer profits

42. Virus resistance Source: Monsanto Herbicide resistant current : soybean, corn, canola, cotton, alfalfa coming : sugar beet, lettuce, strawberry, wheat, Turf grass resistance gene from bacteria papaya, squash, potato resistance gene from a virus

43. Molecular tools are being used for employing bio-fortified varieties of crops “ Bio-fortification” means producing crops that have higher levels of nutrition in their edible parts

44. Golden rice Rice grain White rice Golden rice

45. ‘ Golden Crops’ Source: Gerard Barry Source: Torbert Rocheford

47. Eat fruit, get vaccine A pathogen protein gene is cloned Gene is inserted into the DNA of plant (potato, banana, tomato) Humans eat the plant The body produces antibodies against pathogen protein Human are “ immunized ” Examples: Diarrhea Hepatitis B Measles

48. GM Flower to detect landmines More than 100 million mines are spread over 45 countries

49. Land mines detecting flowers Danish Company: Aresa Biodetection Thale cress: a weed Coded to change colour of flower to red when root comes in contact with Nitrogenous gases evaporating from explosives ! Flowers with in 3-6 weeks of sowings

50. Land Mine Detection Mine detected

51. Feeding Future Populations World has the technology—either available or well-advanced in the research pipeline—to feed 10 billion people Extending the Green Revolution to many more food-insecure people will provide a better diet at lower prices

52. Thanks for your attention /kU;okn