Table of Contents
Wagoner, P., and A. Schauer. 1990. Intermediate wheatgrass as a perennial
grain crop. p. 143-145. In: J. Janick and J.E. Simon (eds.), Advances in new
crops. Timber Press, Portland, OR.
Intermediate Wheatgrass as a Perennial Grain Crop
Peggy Wagoner and Anne Schauer
- RESEARCH APPROACH
- GERMPLASM EVALUATION
- DEVELOPMENT OF CULTURAL PRACTICES
- NUTRITIONAL ANALYSIS AND FOOD USE EVALUATIONS
Present grain crop production is based entirely upon annuals. Given the proper
conditions, these crops can produce spectacular yields. However, annual grains
are not necessarily the best crop for all situations. On hilly or otherwise
marginal land, annual crop production can lead to severe soil erosion. Such
erosion not only costs the farmer in terms of lost nutrients, but it also costs
society in terms of siltation and degradation of water resources. In addition
to being environmentally unsound, annual crop production on such land is often
economically impractical. Alternative crops must be developed for use on land
that can not sustain annual crop production. The development of perennial
grasses as grains could provide such an alternative.
Perennial grains can provide advantages over annuals including lower production
inputs as well as year round soil protection. Mechanical field operations in a
perennial grain system will be greatly reduced because the soil will not be
re-worked each year, thus saving on fuel and labor costs. Seed purchases and
planting would be done every five to ten years rather than every year as with
annual grains. Where legumes are included with plantings of perennial grains,
the need for commercial fertilizers could be reduced. A perennial grain/legume
mixture could be considered analogous to a grass/legume pasture. However,
instead of the primary harvest product being the hay as in a pasture, the
primary harvest product will be the grain from the perennial grass. In some
areas, the perennial grain/legume fields can be used for hay production or
grazed as pastures after the yearly seed harvest. In addition, the use of
perennial grains could rebuild soil structure through increased soil organic
matter, water infiltration and biological activity in the soil. Because the
soil will have vegetative cover during the entire year, wildlife such as game
birds and mammals could also benefit.
In 1983, the Rodale Research Center (RRC) in eastern Pennsylvania initiated a
long term research project to investigate the potential of developing a
perennial grain cropping system. This project is patterned after the ideas
proposed by Dr. Wes Jackson (1985) who initiated the concept of producing
grains from herbaceous perennial plants.
Close to 100 species of perennial grasses were evaluated at the RRC in order to
identify those with good potential for development into perennial grain crops.
Selection of the most promising species was based on the following criteria
Based on these selection criteria, intermediate wheatgrass, Thinopyrum
intermedium (Host) [syn. Agropyron intermedium (Host)
Beauvois], a perennial relative of wheat, appears to have good potential for
development into a perennial grain crop. This native of southwestern Asia and
the Mediterranean region produces seeds which average 5.3 g/1000 seeds
(Schulz-Schaeffer and Haller 1987). Seeds can be mechanically harvested and
threshed using commercially available equipment. Nutritionally, intermediate
wheatgrass is very similar to wheat with slightly higher protein levels (Becker
et al. 1986). The grain can be ground into flour for use in flavorful baked
products such as muffins and breads or cooked as a whole grain, like rice.
Intermediate wheatgrass is a cool season, rhizomatous perennial which is used
extensively for pasture, hay and soil erosion control in the Great Plains and
intermountain West (Hanson 1972). Since 1986, a total of 250 accessions of
intermediate wheatgrass have been acquired by the RRC from a variety of
sources. Half of these were obtained from the USDA Plant Introduction Office
in Pullman, Washington. These PI accessions were originally collected in the
Soviet Union, Iran, Turkey and other areas of the eastern Mediterranean region.
An additional 100 accessions were collected as single plant selections from
breeding lines growing in field plots at the Northern Great Plains Research
Center in Mandan, North Dakota. Several accessions have been obtained directly
from the Soviet Union through the N.I. Vavilov Institute of Plant Industry.
Commercially available varieties of intermediate wheatgrass have also been
obtained from seed companies in the U.S.
- Production of seeds with favorable flavor qualities
- Production of easily threshed seeds
- Manageable seed size (2 g/1000 seeds)
- Synchronous seed maturity
- Resistance to shattering
- Strong non-lodging seed stalks
- Seedheads held above the level of the foliage
- Drydown of seed stalks at maturity
- High potential for mechanical harvest
- Vigorous perennial growth
This germplasm is being tested in small plots at the RRC to determine seed
production capabilities. Seed yield components are being evaluated for each
accession in order to select high yielding lines for future breeding programs.
Characteristics being studied include seed size, measured as weight of 100
seeds, number of fertile florets/seedhead, a measure of seedhead fertility and
fertile tillers/plant. Both seed size and fertility are highly heritable
characteristics in intermediate wheatgrass (Slinkard 1965, Trupp 1965).
Therefore, clonal selection based on these two yield components should be
effective in increasing seed yield.
Seedhead fertility was evaluated in 150 accessions during the 1988 growing
season using the seedset rating method described by Trupp and Slinkard (1965).
Results of seedset ratings conducted at the RRC range from 8% to 52% for the
germplasm tested thus far. Seed size evaluations conducted at the RRC in 1987
and 1988 indicate that the germplasm ranges from 3.6 g to 7.2 g/1000 seeds.
This initial information indicates that there is sufficient variation in the
germplasm to make selections for higher yielding lines.
Characteristics other than fertility and seed size are being evaluated for each
accession. These include number of fertile tillers, synchrony of seed
maturity, retention of spikelets on the rachis (resistance to shattering) and
ease of threshing seeds from the glumes. General growth and vigor parameters
such as resistance to lodging, vigor of spring and fall regrowth, date of 50%
anthesis and presence of diseases such as rust, ergot or Septoria glume
blotch are also being evaluated. Each accession will be evaluated for all of
these characteristics over the next 3 to 5 years as a prelude to crop
Cultural techniques are being examined at the RRC to develop successful low
input methods of producing perennial grains on a commercial scale. Information
developed by the perennial grass seed industry is being adapted to the
production of intermediate wheatgrass grain. Beginning in 1984, plots of
'Oahe' intermediate wheatgrass were established at the RRC using a John Deere
grain drill. Various planting dates and seeding rates have been tested. Best
results are obtained when intermediate wheatgrass is interplanted with a legume
such as white clover in late August (Wagoner and Schauer 1988). Management
practices which are being studied include the use of manure and companion
planted legumes for fertility maintenance as well as the use of fire, mowing
and grazing to maintain plant vigor (Wagoner and Schauer 1988).
Grain is harvested from experimental plots each August using a Massey Harris
small grain combine. Yearly grain yields range from 100 to 500 kg/ha. While
these yields are low compared to annual grains such as wheat, grain yields from
perennial grasses are never expected to be as high as those from annual grains
because part of the perennial plant's energy goes into production of roots
rather than seed. Nevertheless, a perennial grain cropping system which is
well adapted to the environment in which it is growing can be economically
viable. The reduced costs of inputs will make it possible to obtain a net
profit at lower yield levels (Watt 1989). Perennial grains could be grown on
marginal lands that can not support annual crops. There is already legislation
which has taken erodible land out of production. This research is aimed at
providing an alternative use for that type of land. Perennial grains could, in
the future, provide farmers with an economic return from land that may
otherwise remain idle.
Nutritional and food use evaluations of intermediate wheatgrass grain are being
conducted in collaboration with the USDA Western Regional Research Center
(WRRC) in Albany, California. The nutritional qualities of this perennial
grain are similar to wheat and rye. Compared to wheat, intermediate wheatgrass
has a slightly higher protein level with a higher content of the sulfur
containing amino acids, methionine and cysteine. This could be valuable for
complementation with legumes in food applications (Becker et al. 1986). Flavor
qualities of intermediate wheatgrass grain are also good. At the 100%, 66% and
33% wheat flour replacement levels, whole flour from intermediate wheatgrass
grain performed well in baked products such as muffins and rolls. Wheat
flour-perennial grain flour blends were preferred (sweet/nutty) over the wheat
flour control (Burwell 1984).
Farinograph tests of whole grain flours made from several different cultivars
of intermediate wheatgrass were conducted by Tracy Bergman at the WRRC. The
performance of 'Luna' was very similar to that of a high quality dough forming
wheat. Interestingly, 'Oahe' did not compare as favorably. This demonstrates
that th e re may be sufficient variability among the intermediate wheatgrasses
to select and develop lines for different culinary purposes as in wheat.
Perennial grain cropping systems could provide many environmental benefits
through the reduction of soil erosion as well as the reduction of inputs
necessary to produce grain crops. The development of such perennial grain
systems is a long term prospect. It will require research in a range of
disciplines including agronomy, plant breeding, food use evaluation and market
development. This process is not simply the development of a new crop,
it is the development of a whole new approach to grain production on erodible
land based on perennial rather than annual herbaceous plants. The development
of perennial grains such as intermediate wheatgrass is an important step toward
the regeneration of our soil and water resources.
- Becker, R., G.D. Hanners, D.W. Irving and R.M. Saunders. 1986. Chemical
composition and nutritional qualities of five potential perennial grains. Food
Sci. Techn. 19:312-315.
- Burwell, S. 1984. Cooking and baking application of agrotricum and luna grains.
Rodale Test Kitchen, Emmaus, PA.
- Hanson, A.A. 1972. Grass Varieties in the United States. USDA Agricultural
Handbook No. 170. U.S. Government Printing Office, Washington, DC.
- Jackson, W. 1985. New roots for agriculture. Friend of the Earth. San
- Schulz-Schaeffer, J. and S.E. Haller. 1987. Registration of Montana-2 perennial
Agrotriticum intermediodurum Khizhnyak. Crop Sci. 27:822-823.
- Slinkard, A.E. 1965. Fertility in intermediate wheatgrass, Agropyron
intermedium (Host) Beauv. Crop. Sci. 5:363-365.
- Trupp, C. R. 1965. A diallel analysis of seed yield components in intermediate
wheatgrass, Agropyron intermedium (Host) Beauv. M.S. Thesis, Univ. of
- Trupp, C.R. and A.E. Slinkard. 1965. Seedset rating as a measure of fertility
in grasses. Crop. Sci. 5:599-600.
- Wagoner, P. 1988. Perennial Grain Research at the Rodale Research Center-1987
Summary. RRC/NC-88/33. Rodale Press, Inc. Emmaus, PA.
- Wagoner, P. and A. Schauer. 1988. Perennial Grain Production Trials at the
Rodale Research Center-I 987 Summary. RRC/NC-88/32. Rodale Press, Inc. Emmaus,
- Watt, D. 1989. Economic feasibility of a perennial grain: intermediate
wheatgrass. In Grass or Grain 2 Intermediate Wheatgrass in a Perennial Cropping
System for the Northern Plains. North Dakota State University/Rodale Press,
Inc. Fargo, ND/Emmaus, PA.
Last update February 14, 1997