Rice Production Course Water-Saving Irrigation in Rice R

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

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

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

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

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

Reduced river flows IRRI: Rice Production Course

Tubewells and pumps for irrigation 70 60 50 40 India China 30 20 10 0 1966 1995 India (2000): 5 -6 million irrigation tubewells N China (2001): 3 -4 million irrigation tubewells IRRI: Rice Production Course

Groundwater depletion 1 -1. 5 m/y 0. 7 m/y Arsenic! 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) IRRI: Rice Production Course

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

Field water balance lowland rice IRRI: Rice Production Course

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

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

Field water depths in alternate wetting IRRI: Rice Production Course

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

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

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

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

Upland rice Breeding: Aerobic soil Drought tolerant Weed competitive Adverse soil conditions Low inputs (!) => Stable but low yields Unfavorable uplands 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 Lowland HYV traits Water-short irrigated areas ‘Favorable’ uplands IRRI: Rice Production Course

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

New Aerobic Rice Girls… IRRI: Rice Production Course

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) IRRI: Rice Production Course

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

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? IRRI: Rice Production Course

IRRI: Rice Production Course

Hydrology field experiment Beijing, 2001: Explore aerobic rice yield and irrigation water use IRRI: Rice Production Course

IRRI: Rice Production Course

IRRI: Rice Production Course

Total water input (mm) Water treatment (Rainfall) IRRI: Rice Production Course

9 Yield (t/ha) 8 7 6 5 Lowland Aerobic 1 Aerobic 2 4 3 2 1 0 1394 644 577 586 519 469 Flooded -------- Aerobic ---------IRRI: Rice Production Course Water (mm)

IRRI, Philippines: 3 -4 varieties each season one flooded and one aerobic treatment IRRI: Rice Production Course

IRRI, 2001 DS: yield (t ha-1) in K 6/7 Fertilizer: 180 -60 -40 kg ha-1 NPK Pests and diseases: mole crickets (aerobic), stem borer, sheath blight; lodging in B 6144 F IRRI: Rice Production Course

IRRI, 2002 DS: yield (t ha-1) in K 6/7 Fertilizer: 120 -60 -40 kg ha-1 NPK IRRI: Rice Production Course

Water input, including land preparation (mm) Flooded Aerobic Lining of bunds Irrigation Rainfall IRRI: Rice Production Course

Practical experiences IRRI: Rice Production Course

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

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

Irrigation water used (mm) IRRI: Rice Production Course

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

Comparison between farmers’ practice and alternate wetting and drying (dry season 2001) Farmers’ practice Alternate wetting and drying Difference Total water used* (mm) 500 310 190 Pump O&M cost ($ ha-1) 112 69 43 Yield (t ha-1) 5. 7 5. 5 0. 2 Particulars * From transplanting up to harvesting IRRI: Rice Production Course

Partial budget comparison ($ ha-1) Farmers’ practice Alternate wetting and drying Savings Gross benefits 944 911 -33 Variable irrigation cost 148 96 52 ‘Net’ benefits 796 815 19 Particulars Comments irrigation manager and farmer community: can irrigate 30% more area with same amount of water !! IRRI: Rice Production Course

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

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

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

IRRI: Rice Production Course

Results aerobic rice WS 2002; Canarem, Tarlac IRRI: Rice Production Course

Varieties: • Apo • UPLRI 5 • Magat (Hybrid) IRRI: Rice Production Course

Grain yield (T/ha) Yield range: APO (HT) (LT) Yield range: APO : 4. 1 - 5. 9 t/ha UPLRI-5 : 4. 0 - 5. 6 t/ha Magat : 4. 5 - 5. 4 t/ha : 2. 0 – 6. 6 t/ha : 2. 0 – 6. 0 t/ha UPLRI-5 (HT) : 3. 3 – 5. 3 t/ha (LT) : 2. 2 - 5. 3 t/ha IRRI: Rice Production Course

Sustainability issues with increased aerobic conditions IRRI: Rice Production Course

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

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

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

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

Irrigation experiment Varieties: V 1 = Apo V 2 = Magat V 3 = PSB Rc 98 Irrigation: W 1=2/week W 2=1/week W 3=1/2 week W 3=variable IRRI: Rice Production Course

Nitrogen experiment Varieties: V 1 = Apo V 2 = Magat V 3 = PSB Rc 98 Nitrogen: N 1 = 0 kg N 2 = 100 kg N 3 = 140 kg N 4 = 180 kg N 5 = 220 kg IRRI: Rice Production Course

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

Nematode count from lowland rice farmers IRRI: Rice Production Course

Nematode count/g fresh root (Meloidogyne graminicola) 2000 2001 2002 2003 Wet season Dry season AA 6 875 491 2530 1499 2089 AF 9 279 11 1760 27 3054 FF 2 6 4 134 34 380 Sampled from roots at harvest Aerobic Flooded IRRI: Rice Production Course Wet season

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

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

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