1. Rice Production Course Water-Saving Irrigation in Rice R. Lampayan CSWS, IRRI

2. IRRI: Rice Production Course Content Introduction: the water crisis Water-saving technologies Practical experiences Sustainability issues Conclusions

3. IRRI: Rice Production Course Rice grows under lowland conditions: puddled soil, permanently flooded

4. IRRI: Rice Production Course Rice and water 75% of rice is irrigated (75 m ha) Rice requires much water: 3000-5000 l kg -1 rice Irrigated areas consume 80% of all fresh water used; Asia: > 50% of this is for rice

5. IRRI: Rice Production Course Pressure to produce more food (rice) is getting greater because of ever increasing population But also: More people want more industry more drinking water more cities more swimming pools more…. => Water is getting scarce and expensive

6. IRRI: Rice Production Course ? Is this the future for rice production…….

7. IRRI: Rice Production Course Competition, some examples in rice areas…. Cauvery river: Karnataka-Tamil Nadu Ganges river: India-Bangladesh Beijing: 2001: ban on flooded rice ZIS (160,000 ha)-city, industry ZIS:

8. IRRI: Rice Production Course Reduced river flows

9. IRRI: Rice Production Course Tubewells and pumps for irrigation 0 10 20 30 40 50 60 70 19661995 India China India (2000): 5-6 million irrigation tubewells N China (2001): 3-4 million irrigation tubewells

10. IRRI: Rice Production Course Arsenic! 1-1.5 m/y 0.7 m/y Groundwater depletion

11. IRRI: Rice Production Course Conclusion Need to grow rice using less water in water-scarce or water-costly areas Produce enough rice for growing population Decrease cost of rice production Save ‘little’ water in rice => free-up ‘much’ water for irrigation elsewhere and for use by other sectors (industry, cities, other crops)

12. IRRI: Rice Production Course To mitigate the looming water crisis, we need to “Produce more rice with less water”

13. IRRI: Rice Production Course Field water balance lowland rice

14. IRRI: Rice Production Course Water requirements in lowland rice Total season : 675-4450 mm Typical value : 1500 mm

15. IRRI: Rice Production Course Water-saving measures Good puddling Good bund maintenance Land leveling Crack plowing Short land preparation phase Communal seed beds Efficient use of rainfall (cropping calendar) Direct wet seeding ……

16. IRRI: Rice Production Course Water-saving irrigation technologies: Reduce seepage, percolation and evaporation Saturated soil culture Alternate wetting and drying Aerobic rice

17. IRRI: Rice Production Course Field water depths in alternate wetting

18. IRRI: Rice Production Course Yield (t/ha) Continuously flooded Alternate wetting and drying

19. IRRI: Rice Production Course Continuously flooded Alternate wetting and drying Irrigation water (mm) Note: heavy clay soil with shallow groundwater (0-30 cm deep)

20. IRRI: Rice Production Course Yield (t/ha) Total water (mm) Guimba 88-90 (Tabbal et al., 2002) Silty clay loam, groundwater 70-200 cm

21. IRRI: Rice Production Course A fundamental approach to reducing water requirements in rice? Treat rice like any other (irrigated) crop: No puddling, no standing water, aerobic soil

22. IRRI: Rice Production Course Upland rice Breeding: Aerobic soil Drought tolerant Weed competitive Adverse soil conditions Low inputs (!) => Stable but low yields Unfavorable uplands

23. IRRI: Rice Production Course Different idea of rice like upland crop Breeding: from upland rice… Aerobic soil Input responsive Lodging resistant Weed competitive => Stable and high yields Water-short irrigated areas ‘Favorable’ uplands Lowland HYV traits

24. IRRI: Rice Production Course Improved upland… Dryland Rice… Dryland Rice… Han Dao… Han Dao… Aerobic Rice… Aerobic Rice…

25. IRRI: Rice Production Course New Aerobic Rice Girls…

26. IRRI: Rice Production Course Early evidence: Brazil Early evidence: Brazil Active program to develop upland rice varieties and management techniques since the 80’s => High-yielding aerobic varieties: 5-7 t ha -1 with high inputs State of Mato Grosso: 250,000 ha commercial production (sprinkler irrigated)

27. IRRI: Rice Production Course Aerobic rice, Mato Grosso, Brasil Guimarães and Stone, 2000

28. IRRI: Rice Production Course Early evidence: North China Early evidence: North China Program to improve upland rice => Aerobic rice varieties with yield potential of 6-7 t ha -1 Adoption on estimated 190,000 ha (2001) in Rainfed areas where rainfall is insufficient to sustain lowland rice production Irrigated areas where water is scarce/expensive Salt-affected areas Flood-prone areas Q: What is water use, how to manage the crop?

29. IRRI: Rice Production Course

30. Hydrology field experiment Beijing, 2001: Explore aerobic rice yield and irrigation water use

31. IRRI: Rice Production Course

33. Water treatment (Rainfall) Total water input (mm)

34. IRRI: Rice Production Course

35. IRRI, Philippines: 3-4 varieties each season one flooded and one aerobic treatment

36. IRRI: Rice Production Course IRRI, 2001 DS: yield (t ha  1 ) in K6/7 Fertilizer: 180-60-40 kg ha  1 NPK Pests and diseases: mole crickets (aerobic), stem borer, sheath blight; lodging in B6144F

37. IRRI: Rice Production Course IRRI, 2002 DS: yield (t ha  1 ) in K6/7 Fertilizer: 120-60-40 kg ha  1 NPK

38. IRRI: Rice Production Course FloodedAerobic Lining of bunds Water input, including land preparation (mm) IrrigationRainfall

39. IRRI: Rice Production Course Practical experiences

40. IRRI: Rice Production Course Case study Tarlac & Nueva Ecija: Introducing alternate wetting and drying to farmers using shallow or deep wells for irrigation

41. IRRI: Rice Production Course Monitoring inputs: Irrigation water, seeds, fertilizer, pesticides, labor use, etc. And outputs: Grain yield and quality

42. IRRI: Rice Production Course Irrigation water used (mm)

43. IRRI: Rice Production Course Grain yield (t/ha)

44. IRRI: Rice Production Course Particulars Farmers’ practice Alternate wetting and drying Difference Total water used* (mm)500310190 Pump O&M cost ($ ha  1 )1126943 Yield (t ha  1 )5.75.50.2 Comparison between farmers’ practice and alternate wetting and drying (dry season 2001) * From transplanting up to harvesting

45. IRRI: Rice Production Course Particulars Farmers’ practice Alternate wetting and drying Savings Gross benefits944911-33 Variable irrigation cost1489652 ‘Net’ benefits79681519 Partial budget comparison ($ ha -1 ) Comments irrigation manager and farmer community: can irrigate 30% more area with same amount of water !!

46. IRRI: Rice Production Course Crop establishment (traditional technologies) Case study Tarlac and Nueva Ecija, Philippines: Aerobic Rice

47. IRRI: Rice Production Course Farmer-participatory development; central Luzon. 2003: develop also modern technologies Laser-guided land leveling Automated seeder with basal fertilizer application Labor saving Efficient fertilizer use

48. IRRI: Rice Production Course Flush irrigation of the field only!

49. IRRI: Rice Production Course Weed control: traditional technology (plough, lithao, sagad)

50. IRRI: Rice Production Course

51. Results aerobic rice WS 2002; Canarem, Tarlac

52. IRRI: Rice Production Course Varieties: Apo UPLRI5 Magat (Hybrid)

53. IRRI: Rice Production Course Grain yield (T/ha) Yield range: APO : 4.1 - 5.9 t/ha UPLRI-5 : 4.0 - 5.6 t/ha Magat : 4.5 - 5.4 t/ha Yield range: APO (HT) : 2.0 – 6.6 t/ha (LT) : 2.0 – 6.0 t/ha UPLRI-5 (HT) : 3.3 – 5.3 t/ha (LT) : 2.2 - 5.3 t/ha

54. IRRI: Rice Production Course Sustainability issues with increased aerobic conditions

55. IRRI: Rice Production Course Aerobic rice, Mato Grosso, Brasil Guimarães and Stone, 2000 Fertilization 300 kg of 4-30-16 N,P,K at planting; 150 kg ammonia sulfate at 50 DAS Rice production system Yield (kgha -1 ) Rice after 3 years soybeans 4,325 Rice after 1 years soybeans 2,577 Rice monocrop (5 years) 1,160

56. IRRI: Rice Production Course Field experiments at Dapdap (dry season) Irrigation experiment (4 treatments) Nitrogen experiment (5 treatments) Mixed upland-lowland area with sandy-loam soil

57. IRRI: Rice Production Course No more crop growth after tillering….

58. IRRI: Rice Production Course Roots affected by nematodes Healthy Field experiment

59. IRRI: Rice Production Course Irrigation experiment Varieties: V1 = Apo V2 = Magat V3 = PSB Rc 98 Irrigation: W1=2/week W2=1/week W3=1/2 week W3=variable

60. IRRI: Rice Production Course Nitrogen experiment Varieties: V1 = Apo V2 = Magat V3 = PSB Rc 98 Nitrogen: N1 = 0 kg N2 = 100 kg N3 = 140 kg N4 = 180 kg N5 = 220 kg

61. IRRI: Rice Production Course Nematode count at harvest; nitrogen experiment kg N ha -1

62. IRRI: Rice Production Course Nematode count from lowland rice farmers

63. IRRI: Rice Production Course 2000200120022003 Wet season Dry season Wet season Dry season Wet season Dry season Wet season AA6875491253014992089 AF9279111760273054 FF26413434380 Nematode count/g fresh root (Meloidogyne graminicola) Sampled from roots at harvest Aerobic Flooded

64. IRRI: Rice Production Course Conclusions for Controlled Irrigation An average water savings of about 20% was attained in both deepwell and shallow tubewell systems. Forty percent (40%) of water savings has also been attained in some fields. No significant yield difference has been observed between CI and FP plots. Farmers achieved an average increased net profit of about $20 per ha in deepwell and shallow tubewell systems.

65. IRRI: Rice Production Course 1.Identified varieties with yield potential of 6 t ha  1, using about half the water used in lowland rice (Apo, Magat, UPLRI5, and more) 2.Rough management recommendations that can deliver about 4.5 t ha  1 of the yield potential 3.Established a successful partnership to fully develop the aerobic rice technology (IRRI, NIA, PhilRice and farmers) 4.Under water scarcity: extremely urgent to develop sustainable crop rotations (nematodes!) 5.We stand at a successful beginning Conclusions tropical aerobic rice Where are we after 2 years in the program?

66. IRRI: Rice Production Course Yield Low High Water availability Flooded lowland Upland Crack plowing Compaction Good puddling …….. AWD Aerobic rice AWD, aerobic rice “Target domain” Diversification (nonrice crops)