Plant breeding for improving harmony between
agriculture, the environment and societies
Seth C Murray1*, E Charles Brummer2, Wesley T Barber3, Sarah M Collier4, Thomas S Cox5, Randy
Johnson6, Richard T Olsen7, Richard C Pratt8, and Ann Marie Thro9
1Department
of Soil and Crop Science, Texas A&M University, College Station, TX *(sethmurray@tamu.edu); 2Forage Improvement Division, The Samuel Roberts Noble
Foundation, Ardmore, OK; 3Department of Crop Sciences, University of Illinois, Urbana, IL; 4Department of Plant Breeding and Genetics, Cornell University, Ithaca, NY; 5The
Land Institute, Salina, KS; 6US Forest Service, US Department of Agriculture, Washington, DC; 7Agricultural Research Service, US National Arboretum, US Department of
Agriculture, Beltsville, MD; 8Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM; 9National Institute of Food and Agriculture, US
Department of Agriculture, Washington, DC
What is Plant Breeding?: Modern plant breeding is the science of genetically improving plants to achieve goals and better fit production environments.
In Brief
•
Plant breeding has led played a vital role into the successful development of crops to meet the
food and material needs of society.
•
Plant breeders are continually improving the ability of crops to withstand various
environmental conditions, including those associated with global climate change.
•
Reducing agriculture’s impact on the environment while maintaining sufficient production
will require the development of new crops and production practices.
•
Partnerships of ecologists, urban planners, and policy makers with public and private plant
breeders will be essential for addressing future challenges.
Plant Breeding Has Allowed Increased Food, Fiber and Fuel Production
Plant breeding and agronomic improvements have
greatly increased yields of important crops. Five-year
moving averages of US yield were scaled to each
crop’s historical minimum were calculated from
available data (USDA-NASS 2009). The yield of seven
important annual crops shows that yield per unit land
has increased from three- to 11-fold, meaning that
between one-third and one-eleventh as much
land was needed to produce the same amount
of food. This increase confounds improvements from
breeding and from agronomic practices, which are
extremely difficult to separate. Increasing yield
per unit land area and yield per unit input (eg
water and nutrients) results in greater
production to feed a growing human
population without increasing the amount of
land under cultivation.
Plant Breeding Tools Align With Goals Of Food Production and Ecosystem Service
Provision
Goal 1: Breeding to Adapt Plants To The Environment:
Case Studies
Public plant breeding
*The goal of forages breeding is to produce leaf and stem matter as
opposed to grain
*Many forage species are perennial, providing year-round erosion
control, improved water infiltration as compared with those from annual
cropping systems
*Most forage cultivars have been developed by university or government
breeders.
*The forage breeding program at the University of Georgia (UGA) has
developed cultivars in several species developed agreements with
private-sector commercial partners for seed production and marketing
*UGA developed “Jesup MaxQ” tall fescue, a cultivar carrying a nontoxic endophytic fungus greatly improved animal performance weight
gain and feed efficiency
*This program developed the first true dual purpose – grazing and hay –
alfalfa cultivar, “Alfagraze”, followed by several further improved
cultivars. (Bouton 2007).
Non-profit plant breeding
The Land Institute (Salina, Kansas), focuses on breeding crops to fit systems that
mimic the natural ecology of the prairie (Jackson et al. 2009; Glover et al. 2010).
Four specific traits being researched to accomplish this goal are:
(1) perennial structures that allow overwintering of plants to minimize tillage
and soil destruction;
(2) deep roots that can access water and nutrients (see figure)
(3) the ability to grow in biculture or polyculture systems that include
perennial wheat, intermediate wheatgrass, sorghum, legumes such as Desmanthus
illinoiensis, and/or composites such as perennial sunflower;
(4) increasing yield
The use of wild germplasm towards these goals brings desired as well as undesirable
traits into breeding populations; therefore, several decades are required to develop
acceptable perennial food crops for large-scale production.
Private plant breeding
* Breeding for optimum cropping systems: Crops need to be selected to fit into alternative
systems of production such as alternate crop rotations, planting densities, and tillage systems (no –till)
*The ability to maintain high yields under low water stress is one
component of broadly defined “drought tolerance”.
*Corn is the most productive grain crop and has the highest US
acreage thus it is an important target for improvement.
*Because the corn industry is well developed and highly and profitable
most of the commercial breeding and seed production is in the private
sector.
*Pioneer Hi-Bred International is using native diversity in corn,
combined with advanced measurement technologies and statistical
analyses, to develop corn lines that better resist periods of drought.
*The increasing cost of water to farmers places a value on corn
cultivars that are more tolerant to drought conditions, and the value of
these drought-tolerant cultivars will be captured by the private seed
sector, farmers, and society.
* Breeding for new agricultural paradigms: Perennial polyculture systems (see non-profit
plant breeding box) will require extensive breeding.
Perennial Zea, and high biomass maize at Texas A&M
* Producing more with Less: Increased production using less land, water, nutrients, labor and
fossil fuels results in an increase in efficiency with no tradeoffs.
* Adapting to global climate change and breeding for abiotic and biotic stress tolerance:
To continue with the crops we have, let alone improve further improve them, we must select for new tolerance.
Goal 2: Breeding plants to improve the environment: Currently agricultural systems rank low among
systems for providing ecosystems services (Costanza et al. 1997) but this can be altered though breeding.
* Breeding alternative crops and crops for new uses: Crops for soil improvement and
removing toxic chemicals (phyotremediation), crops for perennial agriculture systems , and biofuels.
* Breeding for local adaptation: Tailor plants for individual landscapes.
* Breeding for specific ecosystem services: Urban trees can be bred for services such as
stormwater management, evapotranspirational cooling, and improved air quality. Likewise crops can be bred
for winter cover and soil erosion preventions.
What is Needed?
Need 1: Partnerships with diverse disciplines and stakeholders: Plant breeders understand how to
improve plants but not necessarily the traits that are valued by others.
photo: C. Brummer
photo: J. Glover/ TLI
Photo: Stephen Smith / Pioneer Hi-Bred International
▪ Perennial relatives of corn Zea perennis and Zea dipploperennis regrow year after year and can add
benefits to the agroecosystem.
▪ Cellulosic Biomass is a promising source of energy production but little breeding or genetics has
been conducted to improve total Zea biomass production under low input conditions.
▪ Texas A&M is focusing on improving five core traits for increased biomass yield in dedicated
biomass Zea: perennialism, tillering, regrowth, extreme height and extreme photoperiodism.
Perennial Zea can preserve soil
and tolerate more stress
Exotic photoperiod sensitive plants
produce more early season biomass
* Understanding ecosystems valuation goals: What value is placed on which traits to improve
environment or life quality? There may be tradeoffs in early cycles of breeding so quantifying value is important.
* Adapting to global climate change and breeding for abiotic and biotic stress tolerance:
Awareness of forecasting models for anticipatory breeding of future climates and stresses .
Need 2: Time
* Breeding is a long term proposition : It takes anywhere from 5 to 50 years to breed a new
cultivar and test it for release. This depends both on the crop and on the trait (s) of interest.
Need 3: Support for public sector breeding
* Projects must be supported over the longterm : Research timelines are generally short in the
private sector and in most competitive grants. Other mechanisms to support longterm breeding objectives are
needed.
Literature Cited
Bouton J. 2007. The economic benefits of forage improvement in the United States. Euphytica 154: 263–70.
Costanza R, d’Arge R, de Groot R, Farber S, Grasso M, Hannon B, Limburg K, Naeem S, O’Neill RV, Paruelo J, Raskin RG, Sutton P, and van den Belt
M. 1997. The value of the world’s ecosystem services and natural capital. Nature 387: 253–260.
USDA-NASS (US Department of Agriculture-National Agricultural Statistics Service). 2009. www.nass.usda.gov. Viewed 3 Jun 2011.
A rammet from a perennial plant has
deep roots and early emergence in spring
Acknowledgements
This poster is based on our recently published paper: Brummer, E.C., Wesley T Barber, Sarah M Collier,
Thomas S Cox, Randy Johnson, Seth C Murray*, Richard T Olsen, Richard C Pratt, and Ann Marie Thro.
2011. Plant breeding for harmony between agriculture and the environment. Frontiers in Ecology and the
Enviornment. doi:10.1890/100225 Published online 15 Sept. 2011 and in print in December.
Additional Funding provided by Texas AgriLife Research.