More Genes or More Agronomists?

Paul E. FixenInternational Plant Nutrition Institutepfixen@ipni.net

Achim DobermannInternational Rice Research Institute

a.dobermann@irri.org

ASA, CSSA, SSSA 2010 Annual MeetingOct. 31- Nov. 4 Long Beach, CA

Special Session: Challenges in Achieving a Second Green Revolution

More genes or more

agronomists?

Maize in the U.S.

Rice in Brazil

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

2

4

6

8

10

12

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Gra

in y

ield

, Mg

ha-1

Year

118 kg/ha-yr

[1.9 bu/ac-yr ]

USA Corn Yield Trends, 1966-2009

Double-X to single-X hybrids

Expansion of irrigated area, increased N fertilizer rates

Soil testing, balanced NPK fertilization, conservation

tillage

Transgenic (Bt) insect resistance

Integrated pest management

Precision, high-speed planters

Modified w/ permission: Cassman et al., 2006. Convergence of Agriculture and Energy. CAST.

(underpinning stream of tremendous technological innovation)

Auto-steer tractors

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?

Long-term average maize yields in the Nebraska ecological intensification study

Cont. corn Corn/soybeanMg/ha

Lancaster County irrigated farmer avg 10.6University recommendation 14.0 14.7Intensive high yield management 15.0 15.6

2000-2005.

Study yields from Dobermann et al., 2007.

Irrigated maize in south-Central Nebraska

• 3-county avg irrigated yield = 12.1 Mg ha-1 (2001-2008)• Hybrid-Maize model used to define potential yield (Yp) for each

field-yr and for yield gap estimation– Simulation without limitations from nutrients or pests

Grassini et al., 2010. Field Crops Research.

• Tri-Basin Natural Resources District

• Empty circles = 521 fields in the database

• Solid circles = 123 fields with additional crop management data

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 = 12.1• 21% below avg Yp• 31% below max Yp

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.”

Grain yield per hybrid regressed on year of hybrid release for three plant densities

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..

Hammer et al., 2009.

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 Yp

of maize; they helped reduce yield gaps and enabled better management.

•Agronomic factors interact in complex ways … but well-informed farmers sort through them rather effectively

•Approaching a Yp ceiling in many productive maize growing areas of the U.S.

– What is the water-limited Yp ceiling for rainfed U.S. maize at the farm-level?

Rice in Southern

Brazil

Cerrado

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

Yiel

d to

n/ha

Green revolution(small contribution

from agronomy)

350 Dwarf varieties released without much impact

Impact of semi – dwarfs

2 ton/ha

Agronomic Revolution(little variety contribution)

Limit: varieties with higher yield potential

Impact 2 ton/ha

Creation of FLAR

.................................1968 1995 2002.......................................

Years

?

?

Variety revolution II?

Peter Jennings, FLAR, 2005

“A package of practices to address multiple problems all at once … a 2nd revolution.”

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

Precision management: small details make big differences

1. Plant for maximum yield potential2. Optimize your plant population3. Preventive pest management4. Early weed control5. Balanced nutrition6. Irrigate early & well

6 strategic practices that are NOT site-specific

Precision management practices in RS1. Plant early to maximize yield potential

– Choose right variety; land preparation after harvest

2. Reduce seed rate to 70-80 kg/ha3. 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

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• 9.000 farmers• 1.1 million ha

2009

Rice yields – RS Brazil (1987-2007, IRGA)

Faixas de produtividade<5 5,1-6 6,1-7 7,1-8 8,1-9 9,1-10 >10

Áre

a cu

ltiva

da c

om a

rroz

- %

0

5

10

15

20

25

30

35

20002008

1,7

7,8

27,7

22,3

6,4

0,8

30,2

27

22,8

33,3

13,3

4,7

1,90

Yield distribution among rice farms in RS, Brazil in 2000 and 2008

Instituto Rio Grandense do Arroz

33,48 33,0030,91

26,64

24,12

26,19

15,00

20,00

25,00

30,00

35,00

2002/03 2003/04 2004/05 2005/06 2006/07 2007/08

Custo unitário (R$/saco 50kg)

- 21,8%

Average cost of production

Water use efficiency in RS

4 m3/1 kg of rice

≤ 1 m3/1 kg of rice

2 m3/1 kg of rice

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

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.

Local teams consisting of researchers, farmers, agronomists and agri-business define treatment specifics

• Farmer foundations:– Mato Grosso Foundation– ABC Foundation

• Provide critical linkages• Eager to participate in the

new “flat world” of agronomyResearchers, farmers &

agronomists at Rondonopolis

• 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.

Site factors

Crop SoilFarmer InputsWater qualityClimateWeatherTechnologyEconomics

Decision

Action

OutcomeFeedback loop

Output

Recommendation of right practice, product,

variety, rate, etc.

A schematic of adaptive management … and research

After Fixen, 2007.

Productivity, profitability,durability, environmental impact

Decision Support

Based on scientific principles

Stakeholder input

Parallel adaptive research?

J.B. Passioura, 2010 (CSIRO)

More Genes or More Agronomists?

ASA, CSSA, SSSA 2010 Annual MeetingOct. 31- Nov. 4 Long Beach, CA

Special Session: Challenges in Achieving a Second Green Revolution

Both, but with appropriate balancebetween them in research

investment, adaptation, and adoption

Is that where we are today?

(USDA, 2008; Dept. of Labor, 2008) Compiled by Chris Boomsma, Purdue U.

2006

US$

mill

ion

1998 2000 2002 2004 20060

10

20

30

40

50

60

Year

E Cumulative USDA-Hatch, NRI, NSF, and DOE funding of basic and applied areas of crop improvement research

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

Year1986

19891992

19951998

20012004

Ph.D

. gra

duat

es

0

20

40

60

80

100

120

140

160

Agronomy and crop sciencesPlant breeding and genetics

(USDA, 2008) Compiled by Chris Boomsma, Purdue U.

U.S. land-grant university Ph.D. graduates in agronomy and crop sciences and plant breeding and genetics

More Genes or More Agronomists?

ASA, CSSA, SSSA 2010 Annual MeetingOct. 31- Nov. 4 Long Beach, CA

Special Session: Challenges in Achieving a Second Green Revolution

Both, but with appropriate balance