Michigan State University Extension
Ag Experiment Station Special Reports - SR539201
07/28/98
Science and Human Nutrition, respectively
Introduction
True to its long established history as a civilization builder and sustainer, wheat continues to play a significant role in U.S. and Michigan agriculture. Whether you are a farmer, seedsman, input supplier, elevator operator, miller, or food processor or whether your concern is jobs, economic growth, environmental sustainability, food prices, or preservation ofour greatrural heritage, you cannot afford to ignore wheat.
For Michigan's farmers, 80% or more of whom plant wheat every year, wheat's winter habit, close row spacing, and cool season adaptation add value through alternative weed control opportunities and alternative and complementary peak work periods.
For the food processing industry, wheat is the raw material for innumerable job sustaining products. The majority ofMichigan's annual wheat harvest is milled in Michigan mills to make high quaHty flour, which is in turn used for cookies, cakes, soup thickeners, pie crusts and more. White wheat bran is a primary feedstock for Michigan's enormous cereal industry. Michigan wheat is also ground to produce whole grain cereal products.
The Wheat Industry in Michigan Numerous breeding programs, both public and private, develop varieties which are adapted to Michigan. All available soft wheats are pure lines, but hybrid wheat is still a target of several private breeding programs. For white wheat, whose regional acreage is largely limited to Michigan, Ontario, and New York, the majority of variety development efforts are in the local public institutions. WG Thompsons in Canada and Pioneer Hibred ire the USA also develop white wheat varieties.
In red wheats, several major private companies compete for the large seed markets in Ohio, Indiana, and Illinois. Land grant universities in those states also breed and release red wheats. Many of the products of these breeding prograrm are well adapted to Michigan's wheat growmg environments. Collectively, these soft red wheat breeding programs represent a tremendous engine for soft wheat improvement. In fact, variety trial data from the past three years shows that the best of the newer varieties should propel Michigan's wheat production into a new, higher level of productivity, with yields increasing by five to ten bushels per acre for both red and white varieties.
Farmers can purchase seed from several types of organizadons. The majority of the wheat seed purchased in Michigan arises from the state sanctioned Certified seed system administered by the Michigan Foundation Seed Association (MFSA) and the Michigan Crop Improvement Association (MCIA). In Michigan, Certified seed is produced exclusively from Foundation seed, which is in turn produced from Breeders seed. Most other states allow Certified seed to be produced from Registered seed (itself produced from Foundation) or Foundation seed.
Varieties produced in the Certified seed system are usually released under the Plant Variety Protection Act (PVP) of 1970. Most varieties released by state experiment stations and some released by private companies are processed through the Certified seed systems. For a variety to be eligible for certification in Michigan, it must be on the approved list which is administered by the Michigan Department of Agriculture but originates within MSU's Department of Crop and Soil Sciences. To be sold as Certified seed in Michigan, seed produced elsewhere must have been produced with the same standards as those prevailing in Michigan. This requirement, coupled with the use in Michigan of the three class system (Breeder/ Foundation/Certified) versus the four class system of Indiana, Ohio, Illinois and others (breeder/foundation/registered/certified), causes considerable controversy because much of the Certified seed produced in other states cannot be sold in Michigan because it arises from registered class seed.
There is no legal requirement that seed be derived from the Certified seed system. In fact, MCIA will inspect and "green tag" seed production of varieties not on the list of those eligible for certification. This parallel pseudocertification system can be applied to "brands," i.e. varieties not protected and regulated by the Plant Variety Protection Act (PVP). Non- PVP varieties can be sold under more than one name designation.
Some private companies register their varieties under PVP in a manner that forces sale of the seed as Certified class (Title V option), while others avoid the official certification systems. In this latter group there are some companies whose policies dictate exclusive association of one name with one variety (and vice versa), while others market the same variety under different names either directly or through subcontracts. Some universities have also engaged in this latter practice of releasing varieties as commodities which can be sold under different names.
Certified seed or its equivalent from private sources is used to plant 25% of Michigan's wheat acreage. Many farmers produce their own seed from a small planting of certified seed and are therefore planting most of their wheat with seed that is one generation removed from certified. Seed treatment of farmer- produced seed is fairly common, either by planter box application or through services available at local elevators or seed distributors.
Current Managernent
Michigan wheat is almost exclusively of "winter" habit, and is planted in the fall between mid -September and late October. Wheat would generally follow soybeans, beans, or sugarbeets in a rotation series of three of more years. Seedbed preparation practices vary, but wheat is usually planted after two or more tillage operations. Most wheat is drilled, although broadcast sowing is also practiced. Drilling rates range from 1.3 to 2.3 million seeds per acre, with row spacing set at around 7" on average. Moderate amounts of N, P and K are applied before planting, generally by broadcasting before tillage.
No herbicides are applied to wheat in the fall. Some stand reduction occurs from winter related injury, although the extent of this damage is quite variable and largely undocumented. Maximum yields require spring N application. Farmers will apply 60-150 lbs actual N per acre (average= 701bs/acre), most commonly as urea, either before spring growth commences (frost application) or immediately after greenup. Broadleafweed herbicides are spring applied on 25 -50% of the wheat acreage. Optimal application times vary with the product, but are generally prior to Feekes stage 7 (second internode detectable).
Wheat varieties available for Michigan vary in flowering and harvest dates by as much as seven days. Paradoxically, many of today's highest yielders are also the earliest to mature. Whether this indicates that the early to flower strategy is more advantageous or if the association between earliness and yield is spurious is as of yet unknown.
Seventy to eighty percent of Michigan's wheat is white grained, and most of that is planted in the Thumb region. White wheat is particularly susceptible to preharvest sprouting, although red wheats will also sprout. Sprouting can occur if harvest-ripe wheat is subjected to prolonged periods of excessive moisture coupled with warm temperatures. Sprout damaged wheat is severely penalized in price. This penalty reflects the drastic reduction in flour quality that results from the synthesis of protein and starch degrading enzymes during germination.
Disease and Infestation
Michigan wheat is attacked by numerous disease and insect pests. Wheat spindle streak virus (WSSV), a soil borne and seemingly ubiquitous virus, can cause extensive chlorosis in early spring. Genetic host plant resistance, Based on visual symptom development, is quite abundant in elite soft wheat germplasm. Barley yellow dwarf (BYD) virus also damages Michigan wheat, through both fall and spring infections. Strong host resistance is not currently available for BYD.
The fungi E. tritici (powdery mildew), Septoria tritici S. nodorum (glume blotch), Puccinia recondita (leaf rust), and Fusarium spp .(scab) are all serious and consistent threats to Michigan's wheat crop. Genetic resistance and chemical control measures are both available for all of these except scab, for which neither control strategy is yet available. Besides reducing yield, scab also leads to contamination of wheat grain with mycotoxins. Fungicide use is variable, but probably does not exceed 10% of the acreage in any year. There are many other minor diseases which attack wheat. Total yield loss from diseases is difficult to esdmate but probably ranges from 10-70% in individual fields and approaches 25% or more on a statewide basis.
Hessian fly can cause significant damage to wheat, although outbreaks are sporadic and relatively insignificant on a statewide basis. Cereal leaf beetle is another sporadic pest of wheat. Host resistance exists for both these insect pests, but neither is currently regarded as a high priority.
Economic Impact Wheat at the arm gate in Michigan in 1990 was worth over $100 million. Most of Michigan's annual wheat crop is consumed by local mills. In return, the Michigan milling industry adds an additional $1.5 billion to the wheat industry. Main products from the mills are flour, bran, and whole grain cereals. White wheat bran is in far greater demand than red wheat bran due to flavor and color problems associated with red bran pigments after processing.
Michigan's wheat industry is primarily based on production of soft wheat and its products. Soft wheat differs from hard red and pasta wheats not only in endosperm characteristics, particularly with regard to kernel texture (hardness), bud also in protein strength (in general soft wheats are weaker), and protein content (soft wheats being lower). These differences enable soft wheat flour to be used in a variety of non- bread products such as cookies, biscuits, cakes, soup thickeners, pastries, etc. These sectors of the food industry add substantially more value to the wheat industry in Michigan.
Salient Trends Per acre yield has shown a general increase over the past three decades (Figure 1). Acreage planted has fluctuated considerably over that same period, at the general trend has been downwards (Figure 2). Major developments in farming technology during 30 years include deployment of new, higher yielding varieties, and increased levels of fertilizer and herbicide usage.
Adoption of improved varieties, particularly the white wheats, undoubtedly accounts for the majority of the increase in wheat yields during tht past 30 years. In fact, close analysis of the three- decade geld trends in Figure 2 reveals a clear distinction between the 1980s yield levels and those of the previous two decades, with a clear breakpoint at exactly the time when the varieties Frankenmuth and Augusta were introduced to Michigan farms. The number of varieties of both red and white wheats available for sale in Michigan is increasing. White wheat acreage has been dominated for 10 years by Augusta and Frankenmuth, but they are consistently out-performed in MSU tests by newer soon-to be available white wheats. Numerous state and private origin red grained varieties have been available to Michigan farmers for several years and their numbers are alway's increasing. Recent yield test data clearly demonstrate continued genetic gain for wheat yields.
Michigan residents comprise a diverse group of people, including those of various ethnic backgrounds, trendsetters vying for novel food products, and health conscious individuals. For these reasons, as well as others, new soft wheat products introduced into the marhet are finding room in the kitchens of this state.
Assumptions for the 1990s
Wheat acreage will grow moderately with the current balance between red and white wheat shifting slightly towards red wheat. Soft winter wheat will continue as the predominant market class. The price of wheat will move upwards during the next decade but not dramatically. Conventional plant breeding efforts will bring a continuous stream of new varieties into Michigan. Continued genetic gains will be manifest in both yield potential and yield stability through both improved pest resistance and general adaptation and physiological efficiency. Pressure to decrease chemical inputs will increase, although input usage will remain relatively constant, and fungicide applications could increase. No major changes are evident in the pest scenario, although fluctuations will occur as to which pests cause damage in which years. Wheat acreage planted in reduced tillage systems could increase substantially. Input management will be continuously refined as farmers become increasingly more knowledgeable about the biology of wheat and its pests.
Utilization of different products extracted from mills will increase. The food industry will increase the variety of soft wheat products, particularly those targeted to different ethnic groups and to the health conscious sector in our society. Higher quality of products will be expected by more knowledgeable consumers.
Technological Developments in the 1990s and Beyond Genetic Improvement
Short term: conventional plant breeding will continue to generate improved varieties. Wheat's natural genetic variation will allow continued improvements in grain yield and in development of more durable resistances to powdery mildew, leafrust, and WSSV. Reports from China of high levels of scab resistance in a close bat wild relative of wheat are tantalizing and may provide new opportunities for combatting this disease. The soft white germplasm base will be considerably expanded by introgression of improved gene complexes from the more dynamic soft red germplasm. Genes from wheat's relatives (rye, barley, goat grass, etc. ) will continue to contribute to wheat's yield potential, disease resistance, and winter hardiness. Micro tests for more specific end use products will be further developed, enabling greater precision in selecting superior processing-quality wheats.
Long term: The breeding programs of the future will seamlessly incorporate both biotechnology and conventional breeding approaches.
Conventional breeding techniques will continue to discover improved combinations of native genes for a very long time. The wealth of native genetic diversity of wheat, or any crop for that matter, has barely been touched in the almost 100 years that genetics based plant breeding has been practiced. Molecular marker technologies will facilitate both the identification and manipulation of the myriad genes influencing complex traits such as yield and development strategy. Biotechnology derived genes will extend wheat's native range of genetic potential. Once incorporated into wheat, they will be indistinguishable from native wheat genes.
Current researc on the genetics and physiology of growth and development strategies at MSU and elsewhere will lead to ever refined definitions of the ideal wheat plant for Michigan. For instance, the ideal wheat plant may flower at the same time as today's earliest (and overall highest yielding) genotypes, but mature even later than today's latest maturing genotypes. Once confirmed as a sensible goal, such a developmental strategy might be achieved through conventional or iotechnological approaches.
Biotechnologies for the direct insertion of new genes (transformation) into wheat are nearing the application phase of development. The next limiting factor will be the availability of novel, performance- enhancing genes for transformation. Genes encoding the protein coat of barley yellow dwarf virus are being cloned and may provide the basis for resistance to the disease once they are inserted into wheat. WSSV may also be attacked in this way. General anti-fungal genes may yield some measure of durable resistance to leaf rust, powdery mildew, scab, etc. Abiotic stress resistances may also be achieved through transformation with genes whose products mediate internal stresses due to heat, water, or freezing stress.
Seed dormancy research will lead to increased dormancy of white and red wheat varieties. Molecular studies of the events during seed maturation, dormancy, and germination will eventually enable the biotechnology mediated elimination of sprouting as a problem. Wheat of the early to mid -21st century could arguably all be completely dormant and white grained, since that market class generally provides the greatest flexibility in end use applications. Perhaps wheat will be genetically engineered to be permanently dormant except in the presence of a chemical agent applied in the manner of a standard seed dressing.
The identification of specific seed components and the corresponding genetic systems which condition differential functionality of wheat in various end use products wffl enable more focused improvement of processing quality. This will result in a further splintering of the current market classes and ultimately lead to contract acreage and identity preservation systems.
Production Pressures to reduce soil erosion, groundwater contamination, and general pesticide use will dictate changes in the management of wheat ire Michigan. Minimum tillage planting systems wl ommate Mic igan wheat acreage in the future, and fertilizer use will be more carefully managed. Fungicides and herbicide usage will be more closely tied to economic and environmental responses.
The Seed Certification system should continue to play a significant role in ensuring the purity and identity of wheat seed, but serious challenges could arise from private seed companies which choose not to certify their varieties. Hybrid wheat remains a tantalizing possibility. Recent refinement of chemical gametocides for the first time allows hybrid wheat breeders to search for heterosis on the same scale as has been applied in sorghum and maize. Only time will tell if adequate levels of superiority of hybrids over pure lines can be found.
Utilization
Short term Parameters of soft wheat quality are not as clearly defined as for bread and pasta wheats. Precise methodologies to quantify the quality of soft wheat for milling and baking performance need to be determined. Rapid tests to screen soft wheat lines for the presence of 1B/1R translocation genes from rye are required. These rye genes have a great impact on bread wheat processing quality. Rapid analyses will be developed to assess the quality of new varieties and commercial lots of soft wheat. New processing techniques will be introduced to utilize partially sprouted wheat in various food and non-food products. New products will be developed from a variety of flour constituents.
Long term The flour constituents (their relative amounts, molecular structure, and properties) that control, or contribute to, the functional properties during processing will be identified. Modification ofprocessing (e. g ., milling, dough mixing, baking, etc .) to maximize the yield and quality of the end product will be developed. Certain flour constituents will be explored for use in the food industry (starch and vital gluten) as well as for other industrial uses (starch for glue, protein for biodegradable polymers). These directions will be the keys to a competitive edge in national and international markets that lead Michigan's wheat industry into the 21st century.
Opportunities/Imperatives for Wheat Research and Extension at MSU
Michigan State University should deploy its resources to:
1. Ensure continued cultivation of wheat by continuing the long tradition of aggressive development and deployment of high yielding and high quality soft wheat varieties, with particular emphasis on white wheat.
2. Increase the value and expand the marketability of Michigan wheat products through continued and enhanced support of the newly created cereal scientist position in the Department of Food Science and Human Nutrition. That position would particularly benefit from creation of technical positions dedicated to supporting its research mission.
3. Shore up the Michigan farmer's defense against new biotic threats by enhancing support for MSU pathologists and entomologists.
4. Increase communication among all Michigan wheat industry components by continued and enhanced support for wheat extension.
Oats and Barley Russet Freed, Department of Crop and S@il Sciences
Oats
The significance of oats as a small grain crop in Michigan's production system is not adequately represented by acreage figures. Oats is grown both as a grain and a forage crop. Both play key roles in crop rotations to reduce disease, insect and weed build-ups, and to provide straw for livestock bedding. Oat grain has the highest protein levels among temperate cereals and a very desirable amino acid balance for young animals and nonruminating livestock. Each year a significant percentage of the harvested crop is utilized as human food.
Oats is an important cas crop per se or many farmers and serve as a locally produced, high-value feed crop especially in dairy and poultry industries. As a spring crop, it spreads out labor utilization and at harvest provides an early season cash flow. Some farmers use oats as a bow-cost means of establishing new legume seedings. Oats is one of the few crops which can be successfully grown on compacted soils resulting from wet season sugarbeet harvesting operations.
Production trends for oats in Michigan are downward. In 1960, the state harvested 36 million bushels. During the 1980s, production varied from 28 million in 1982 to 6 million in 1988. The major reason for this downward trend has been the importation of large quantities from European Economic Community sources. In 1991 the U.S. imported 70 million bushels from Sweden and Finland where farmers received a subsidized price of over five dollars per bushel.
During the last 30-year period, U.S. oat yields have been edging up, largely as a result of new and improved varieties. The development of new oat varieties has the potential of increasing yields another 20 bushels per acre. With the continued improvement in yields, there is a potential of increasing oat acreage in Michigan. No major changes in the demand for oats can be predicted. Animal feed and human food demands will not change significantly. The advent of new varieties and varieties with specific market demand characteristics will serve Do maintain or increase oat yield levels or to target specific market niches.
Production Technology will continue to focus on systems which require fewer purchased inputs. Other changes in production technology will focus upon very early spring planting to take advantage of that portion of the growing season most favorable for oats.
Barley yellow dwarf and crown rust are two diseases which significantly reduce yields in Michigan. These two diseases are controlled by using varieties with tolerance to the diseases.
Both state- and federally -supported research programs are reducing the number of full-time equivalent scientists working on oats. This is closely linked to the acreage sown to this crop. However, many regions are uniquely situated to take advantage of this crop's potential. For example, Michigan can compete very effectively in the horse feed market, which demands large seeded white oat types.
The sustainability of our systems of agriculture will remain as a dominant issue in our society. Plant breeding programs in all crops can continue to have a significant impact on Michigan crops. Breeding of improved varieties can reduce chemical use, such as pesticides, decrease unit costs through increased yields, reduce losses due to drought and temperature extremes, improve nutritional qualities, and reduce fertilizer costs through more efficient nutrient uptake. Global climate change will require the development of new varieties if Michigan farmers are to remain compedtive.
A major unresolved issue is the ownership of new and improved genetic materials. This becomes especially true in a minor crop such as oats. Patents held by individual scientists on agricultural inventions could become a problem. State support for research through which the scientist can claim royalties for unique discoveries may not be appropriate. Incentives for excellence, other than royalties, need to be explored.
Barley
Barley has been an important spring cereal for Michigan's farmers for much of this century. However, Michigan barley acreage has gone down from 60,000 acres in 1986 to 45,000 acres in 1990. Only about 10,000 acres are planted specifically for the malting barley market, while the remainder is grown as feed barley.
Since the Stroh Brewery in Detroit ceased its malting operations, malting barley purchased in Michigan has been shipped to Chicago, Buffalo, or other points for processing. With a widespread glut in the barley market, Michigan barley has not been competitive. Barley produced under our more humid growing conditions is not conducive to the production of "bright," the barley characteristic of dryer regions. "Brightness" is a trait sought agter by the malting industry.
Barley is an excellent feed crop and can be effectively substituted or corn in rations or beef and dairy cattle. It can be harvested and ensiled as a high-moisture feed or, when ground, used in mixed feed concentrates. Barley can be grown in shorter-season, lower temperature regions, which makes it an ideal substitute for corn in northern latitudes.
Barley, like oats, has relatively low production costs and is an excellent crop in rotation with more intensively managed farm operations. It can be planted very early in the spring and can be used to spread out work loads and provide mid-season cash flows.
With the present cash grain demand levels, there is little reason to predict the re-emergence of barley as a major crop in Michigan. It can be grown successfully in the state and will continue to serve a variety of local purposes.