More Genes or More Agronomists?

Transcription

1 ASA, CSSA, SSSA 2010 Annual Meeting Oct. 31- Nov. 4 Long Beach, CA Special Session: Challenges in Achieving a Second Green Revolution More Genes or More Agronomists? Paul E. Fixen International Plant Nutrition Institute pfixen@ipni.net Achim Dobermann International Rice Research Institute a.dobermann@irri.org

2 Maize in the U.S. Rice in Brazil More genes or more agronomists?

3 Optimistic claims on the impact of additional gains for maize from biotechnology Boost average U.S. maize yields to 19 Mg ha -1 (300 bu/a) by 2030 (Monsanto, 2008). Single transgene interventions for drought tolerance providing additive 15% yield jumps every 5 years (Edmeades, 2008). Potential to lead to the under valuing of other factors in advancing these traits

4 12 10 USA Corn Yield Trends, (underpinning stream of tremendous technological innovation) 118 kg/ha -yr [1.9 bu/ac -yr ] Soil testing, balanced NPK fertilization, conservation tillage Transgenic (Bt) insect resistance Grain yield, Mg ha Double-X to single-x hybrids Expansion of irrigated area, increased N fertilizer rates Integrated pest management Precision, high-speed planters Auto-steer tractors Year Modified w/ permission: Cassman et al., Convergence of Agriculture and Energy. CAST.

5 Nitrogen Partial Factor Productivity for Corn in the U.S. substantial gains as yields climbed Yet cereal grain crop recovery often ranges below 50% in season of application Source of future gains?

6 Long-term average maize yields in the Nebraska ecological intensification study Cont. corn Corn/soybean Mg/ha Lancaster County irrigated farmer avg 10.6 University recommendation Intensive high yield management Study yields from Dobermann et al., 2007.

7 Irrigated maize in south-central Nebraska Tri-Basin Natural Resources District Empty circles = 521 fields in the database Solid circles = 123 fields with additional crop management data 3-county avg irrigated yield = 12.1 Mg ha -1 ( ) Hybrid-Maize model used to define potential yield (Y p ) for each field-yr and for yield gap estimation Simulation without limitations from nutrients or pests Grassini et al., Field Crops Research.

8 Tri-Basin irrigated yields and simulated yield potential based on avg management practices and weather records Dashed line based on practices giving highest yd (RM, pop, sowing date) 8-yr avg = % below avg Y p 31% below max Y p Risk factors: Frost before PM Harvest problems Seed costs, lodging Authors: limited potential for further increases in irrigated maize yields without a substantial increase in the current Yp ceiling. brute force breeding agronomic research to exploit interactions.

9 Grain yield per hybrid regressed on year of hybrid release for three plant densities Hammer et al., As in the past, future yield increases will not be due to genetic improvement alone, but to changes in several interacting factors, with better agronomy always playing a major role..

10 Observations on these high yield maize systems Continuous yield and efficiency improvement appear associated with both genetic and agronomic changes None of the genetic interventions have increased the Y p of maize; they helped reduce yield gaps and enabled better management. Agronomic factors interact in complex ways but wellinformed farmers sort through them rather effectively Approaching a Y p ceiling in many productive maize growing areas of the U.S. What is the water-limited Y p ceiling for rainfed U.S. maize at the farm-level?

11 Rice in Southern Brazil

12 Cerrado

13 Rice area, production and yield in the Southern Cone, South America

14 Variety revolution II??? Agronomic Revolution (little variety contribution) Limit: varieties with higher yield potential 350 Dwarf varieties released without much impact Impact 2 ton/ha Yield ton/ha Green revolution (small contribution from agronomy) Impact of semi dwarfs 2 ton/ha A package of practices to address multiple problems all at once a 2 nd revolution. Creation of FLAR Years Peter Jennings, FLAR, 2005

15 Latin American Fund for Irrigated Rice (FLAR) South South platform that seeks synergy in rice R & E Established in 1995 A strategic alliance among public and private institutions of LA rice sector Annual fee based on country rice production Total budget of $1.4 million Projects on: Breeding Agronomy to reduce country yield gaps (in 19 countries) Economy and markets

16 Precision management: small details make big differences 6 strategic practices that are NOT site-specific 1. Plant for maximum yield potential 2. Optimize your plant population 3. Preventive pest management 4. Early weed control 5. Balanced nutrition 6. Irrigate early & well

17 Precision management practices in RS 1. Plant early to maximize yield potential Choose right variety; land preparation after harvest 2. Reduce seed rate to kg/ha 3. Preventive pest management Seed coating (insecticide, fungicide); fungicide (PI-F) 4. Preventive and early weed control: Pure seed; Clearfield varieties, crop rotation Herbicide at V3-V4 5. Balanced nutrition with high NUE Basal NPK placed with seed (2 x 2 ) High N dose at V3-V4 on dry soil (pre-flood) Topdress N at PI (airplane) 6. Irrigate early Irrigate at V3-V4 and keep flooded Harvest and recycle water

18 Instituto Rio Grandense do Arroz (IRGA) 420 Staff Research & extension $30 million/yr 100% farmer-funded $0.20/sack rice 6 Regions 40 Offices 38 Agronomists 22 Technicians farmers 1.1 million ha

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20 Rice yields RS Brazil ( , IRGA) 2009

21 Yield distribution among rice farms in RS, Brazil in 2000 and 2008 Área cultivada com arroz - % ,2 1,7 27 7,8 22,8 27,7 13,3 33,3 4,7 22,3 1,9 <5 5,1-6 6,1-7 7,1-8 8,1-9 9,1-10 >10 Faixas de produtividade 6, ,8

22 Average cost of production 35,00 33,48 33,00 30,91 Custo unitário (R$/saco 50kg) - 21,8% 30,00 26,64 26,19 25,00 24,12 20,00 15, / / / / / /08 Instituto Rio Grandense do Arroz

23 Water use efficiency in RS 4 m 3/ 1 kg of rice 2 m 3/ 1 kg of rice 1 m 3/ 1 kg of rice

24 Key elements of success Systematic approach for better agronomy instead of a fragmented product-centric approach Common goal and agronomic principles that can be easily communicated and implemented Large-scale technology solutions that match farmers needs Focus on farmer-to-farmer extension Extension support mechanisms Knowledgeable, motivated field agronomists (IRGA, private consultants) Local partnerships (technical working groups) Focused applied research program (IRGA) Self-sustained: paid and driven by farmers Teamwork

25 IPNI Global Maize Project: Objectives Determine and demonstrate the yield gap in various maize regions of the world. Determine what nutrient management and other practices need to change to close the yield gap faster than the current trajectory.

26 Local teams consisting of researchers, farmers, agronomists and agri-business define treatment specifics Researchers, farmers & agronomists at Rondonopolis Farmer foundations: Mato Grosso Foundation ABC Foundation Provide critical linkages Eager to participate in the new flat world of agronomy Adaptive research linked to adaptive management: Transforms good practices based on scientific principles into best practices based on local practical experience Potential to shorten the time between discovery and impact.

27 A schematic of adaptive management and research Site factors Crop Soil Farmer Inputs Water quality Climate Weather Technology Economics Parallel adaptive research? Stakeholder input Decision Support Based on scientific principles Output Feedback loop Recommendation of right practice, product, variety, rate, etc. Decision Outcome Action Productivity, profitability, durability, environmental impact After Fixen, 2007.

28 J.B. Passioura, 2010 (CSIRO)

29 ASA, CSSA, SSSA 2010 Annual Meeting Oct. 31- Nov. 4 Long Beach, CA Special Session: Challenges in Achieving a Second Green Revolution More Genes or More Agronomists? Both, but with appropriate balance between them in research investment, adaptation, and adoption Is that where we are today?

30 2006 US$ million E Cumulative USDA-Hatch, NRI, NSF, and DOE funding of basic and applied areas of crop improvement research (USDA, 2008; Dept. of Labor, 2008) Compiled by Chris Boomsma, Purdue U Year Genome, genetics, and genetic mechanisms [1] Genetic resources and biodiversity [2] Basic plant biology [3] Biological efficiency and abiotic stresses [4] Product quality and utility [5] Production management systems [6] Predominately basic Mixture of basic & applied Predominately applied

31 U.S. land-grant university Ph.D. graduates in agronomy and crop sciences and plant breeding and genetics Ph.D. graduates Agronomy and crop sciences Plant breeding and genetics Year 1998 (USDA, 2008) Compiled by Chris Boomsma, Purdue U

32 ASA, CSSA, SSSA 2010 Annual Meeting Oct. 31- Nov. 4 Long Beach, CA Special Session: Challenges in Achieving a Second Green Revolution More Genes or More Agronomists? Both, but with appropriate balance