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Cultivating perennial crops such as intermediate wheatgrass, (IWG) (Thinopyrum intermedium), benefits the environment, e.g. by reducing nitrogen run-off compared to cultivation of annual crops like wheat. However, IWG's ability to form a gluten-network is low, and processing modifications may be needed to improve it. Our objective was to study the effect of bran reduction and addition of dough conditioners (wheat protein isolate, vital wheat gluten, ascorbic acid, xylanase, transglutaminase) on extensibility, resistance to extension and protein secondary structures of IWG dough. Grain kernels were analyzed for dimensions and chemical composition. IWG from two locations was used, hard red wheat served as reference. IWG kernels were thinner, lighter, and of lower bulk density than wheat; flour contained more insoluble dietary fiber, protein and ash; and dough was less extensible. Growing location affected fiber and protein content, and was associated with structural and rheological differences. Bran addition increased β-sheets and resistance to extension, but decreased β-turns and extensibility. Transglutaminase increased resistance to extension and affected protein conformation, especially α-helices. Wheat proteins addition had similar, but less pronounced effects. Future studies to evaluate different levels and combinations of dough conditioners, and their effects on bread characteristics, are needed.

Thinopyrum intermedium, known as intermediate wheatgrass (IWG), is one of several perennial crops available for potential food use. The overall objective of this work was to investigate the chemical, functional, and baking properties of wholegrain flour obtained from the grains of 16 IWG breeding lines. Compared to wholegrain wheat flours, IWG wholegrain flours had higher protein, dietary fiber, and ash, yet were lower in starch content and deficient in high molecular weight glutenins. The ratios of amylose to amylopectin among the wholegrain flours of IWG and wheat were similar, but IWG flours exhibited lower viscosity during heating and cooling. Dough from IWG flour had lower stability, resistance to extension and extensibility compared to dough from wheat flour. While bread from IWG flour had similar specific volume to one of the wheat flours, it had lower rising capability due to weaker gluten network forming ability. Although IWG flour might not be ideal for bread products that require rising properties, results indicated that it could be suitable for other applications. This work provided quality trait information that is useful for plant breeders in their effort toward the development of IWG lines for food use.

As aboveground biomass of perennial grasses is harvested for feedstock or bioenergy production, root biomass C and N become primary C and N inputs for enhancing soil C and N sequestration. Information is scanty about root biomass C and N and subsequent soil C and N stocks under bioenergy perennial grasses applied with various N fertilization rates in semiarid regions. We evaluated the effect of perennial grass species and N rates on root biomass C and N and soil total C (STC) and total N (STN) stocks at the 0–120 cm depth from 2011 to 2013, 2–4 yr after grass establishment, in the northern Great Plains, USA. Perennial grasses were intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth and Dewey), smooth bromegrass (Bromus inermis L.), and switchgrass (Panicum virgatum L.), and N fertilization rates were 0, 28, 56, and 84 kg N ha−1. Root biomass C and N at 0–15 and 0–120 cm were greater with intermediate wheatgrass and switchgrass than smooth bromegrass in 2011, but the trend reversed for root biomass C at 0–15 cm in 2012. Root biomass C at both depths among N rates and years. The STC at 0–15, 30–60, and 0–120 cm also varied among grass species and years. At 30–60 cm, STC increased with increased N rates under intermediate wheatgrass and switchgrass, but decreased under smooth bromegrass. At 60–90 cm, the trend for STC reversed. The STN at 15–30 cm was greater under intermediate wheatgrass than smooth bromegrass and switchgrass and at most depths was greater in 2012 than 2013. Overall root biomass C and N at 0–120 cm were 12–16 times greater and STC and STN 8–9% greater under perennial grasses than adjacent annual spring wheat. Although intermediate wheatgrass returned more root C and N to the soil than other grasses, both STC and STN varied among grass species and N rates. Increased root C and N inputs, however, increased STC and STN under perennial grasses compared with annual spring wheat.

International audience; Intermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey) is being developed for use as a new perennial grain crop through breeding and agronomic research. However, progress has been hampered by lack of understanding of environmental requirements for flowering and grain production. Therefore, we developed a phenology model for IWG adapted from the STICS soil-crop model. The model was compliant with experimental results (relative root mean square error = 0.03). The optimal vernalizing temperature was between 4 and 5 • C, optimal daylength between 13 and 14h, while daylength below 11h slowed reproductive development. Vernalization requirement was found to be a constraining inductive process. Including a photoperiod limitation to the model with temperature improved its ability to predict induction at various latitudes. Therefore, timing and duration of vegetative vs. reproductive growth may differ between environments and change reproductive tiller elongation earliness, weed competitiveness, management timing, and stress conditions during phases critical to grain yield. Accurate phenology models will enable optimal field management and inform future breeding strategies. However, plasticity may lead to divergent ideotypes under various agroecosystems.

The high protein and fiber content of intermediate wheatgrass (IWG) - together with its interesting agronomic traits and environment-related benefits - make this perennial crop attractive also for human consumption. Structural characteristics of the proteins in IWG/hard wheat flour (HWF) doughs (at IWG:HWF ratios of 0:100, 50:50, 75:25 and 100:0) - including aggregate formation, thiols availability, and secondary structure changes during dough mixing - were investigated. Proteins in IWG-doughs had higher solubility and thiol content - as function of IWG content - suggesting that protein network was mostly based on non-covalent interactions. While 50% IWG-enrichment gave an increase in random structures, enrichment at ⩾75% resulted in a decrease in β-sheets with an increase in random structures, indicating a decrease in structural order. The observed differences in protein molecular configuration and interactions in HWF compared to IWG doughs necessitate further investigation to establish their impact on the quality of IWG-enriched bread.

Intermediate wheatgrass ( Thinopyrum intermedium ; IWG), is a perennial crop that is well-known for providing good environmental services. As a perennial relative of wheat, IWG has good potential for development into a perennial grain crop. But the diversity and potential of the end-use quality of IWG grain are still unknown. Here, to understand the end-use quality of IWG, we investigated the variability among seed from 60 IWG genotypes in high-molecular-weight glutenin subunits (HMW-GS), protein polymerization, and mixing characteristics. IWG genotypes have high grain protein content, ranging from 16.4 to 23.6%. Of the total proteins, the percentage of polymeric proteins show a large range across IWG genotypes, varying from 9.2 to 25.1%. Many genotypes have limited amounts of polymeric proteins, but several genotypes have large amounts of polymeric proteins and promising mixing properties, comparable to common wheat, Triticum aestivum . The amount of protein polymers in the SDS buffer unextractable fraction are significantly correlated (r ≥ 0.76) with mixograph parameters. Furthermore, we observed that HMW-GS variants showed differential contribution to protein polymerization and mixograph parameters. But the composition of HMW-GS in IWG was contributed by both parents, which might bring challenges for the evaluation of grain quality of open-pollinated IWG genotypes.

In comparison to the annual grain crops dominating current agricultural production, perennial grain species require fewer chemical and energy inputs and improve soil health and erosion control. The possibility for producing sustainable grain harvests from marginal land areas is motivating research initiatives to integrate perennial grains into commercial cropping and food processing systems. In this study, the feruloylated arabinoxylans from intermediate wheat grass (Thinopyrum intermedium, IWG), a promising perennial grain candidate in agronomic screening studies, were investigated. Insoluble fiber isolated from IWG whole grain flour was subjected to either mildly acidic (50 mM TFA, 100 °C, 2 h) or enzymatic (Driselase) hydrolysis. The liberated feruloylated arabinoxylan oligosaccharides were concentrated with Amberlite XAD-2, separated with gel chromatography (Sephadex LH-20, water), and purified with reversed-phase HPLC (C18, water-MeOH gradient). Thirteen feruloylated oligosaccharides were isolated (including eight structures described for the first time) and identified by LC-ESI-MS and NMR. Linkage-type analysis via methylation analysis, as well as the monosaccharide and phenolic acid profiles of the IWG insoluble fiber were also determined. IWG feruloylated arabinoxylans have a relatively simple structure with only short feruloylated side chains, a lower backbone substitution rate than annual rye and wheat varieties, and a moderate phenolic acid content.

Kernza intermediate wheatgrass is the first perennial grain crop in the world and has been developed with conventional breeding to increase seed yield of forage intermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey). When managed for dual-use (grain and forage), Kernza intermediate wheatgrass can produce grain, crop residue (straw) in the summer, and green forage in the spring and fall. Mixtures of this grass with legumes could increase forage yield and nutritive value and provide other environmental and economic benefits. Despite the growing interest in these dual-use production systems, forage nutritive value of Kernza intermediate wheatgrass forage in a dual-use system in the Upper Midwest is unknown. A replicated field experiment was established in two locations in southern Wisconsin (Arlington and Lancaster) with two treatments: Kernza intermediate wheatgrass grown in monoculture and mixture with red clover (Trifolium pratense L.). Forage samples were collected at late vegetative stage in the spring, at grain harvest in the summer, and at the end of the regrowth period in the fall. Forage nutritive value of the monoculture was greatest in the spring with 456, 249 and 225 g kg−1 for neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude protein (CP), respectively; lowest in the summer with 702, 427 and 51 g kg−1 NDF, ADF and CP, respectively, and intermediate in the fall with 590, 337 and 119 g kg−1 NDF, ADF and CP, respectively. Predicted total-tract neutral detergent fiber digestibility (ttNDFD) was 0.53 for the spring forage and averaged 0.37 for the summer and fall forage, with no differences between the mixture and monoculture. The relative forage quality (RFQ) for the monoculture was 175 for the spring forage, 65 for the summer residue, and 116 for the fall. Intercropping red clover with Kernza intermediate wheatgrass increased CP of the summer crop residue by 69%, and increased CP and RFQ of the fall forage by 49% and 11%, respectively, while reducing NDF and ADF of the fall forage by 25% and 18%, respectively. Therefore, Kernza intermediate wheatgrass forage is suitable for lactating beef cows, dairy cows, and growing heifers when harvested in the spring and fall, and it offers high potential for dual-use grain and forage systems.

Efforts are underway to establish the perennial grain intermediate wheatgrass (IWG, Thinopyrum intermedium) as food ingredient due to environmental benefits provided by its cultivation. IWG contains more protein than wheat but exhibits poor gluten-forming ability. This study evaluated if refinement or dough conditioners (wheat protein isolate, vital wheat gluten, ascorbic acid, a commercial enzyme blend, and transglutaminase) could compensate for this characteristic. Dough stickiness and physical attributes of breads made with IWG from two growing locations that was either completely, partly or un-refined were measured. In completely or partially refined breads from one location, transglutaminase reduced stickiness (from 0.721 ± 0.022 and 0.494 ± 0.012 to 0.602 ± 0.007 and 0.309 ± 0.006 N, respectively). However, in unrefined breads it resulted in unacceptably dense crumb, decreasing cell counts from 237 ± 16 to 93 ± 22 and 311 ± 28 to 86 ± 7 per area viewed, depending on growing location. In contrast, ascorbic acid improved crumb structure in completely refined breads, decreasing cell counts (from 247 ± 3 to 129 ± 6 and 356 ± 23 to 104 ± 4 per area viewed, depending on growing location) while increasing average cell size. Moreover, surfaces of breads made with ascorbic acid were smooth, while absence or use of other conditioners resulted in uneven, unappealing appearance. These results highlight how processing can improve IWG functionality.

Western European agriculture is largely defined by the high level of productivity of its cereal grain production. Such productivity is largely a result of farm specialization and intensification. This approach however has led to environmental problems and farm sensitivity to climatic and economic hazards. Recently, perennial grains have been promoted as a potential alternative, particularly with intermediate wheatgrass (Thinopyrum intermedium). Perennial grains bring new perspectives and innovation, and can contribute to both system diversification and environmental performance. Above all, the value of year-round ground cover and root activity, as well as the ability to harvest both grain and forage production, offers a large range of interest and potential application for such a grain crop. Realization of the potential benefits from perennial grains depends on the development of suitable seed material and the identification of tangible economic and environmental benefits coming from the integration of perennial grains into crop rotations. Although more work is needed, perennial grains are compatible with the current European interests and policies for food security, soil health, water quality, and farmer interest in innovative practices and sustainable cropping systems.

Perennial grain crops may confer greater ecosystem services relative to annual row crop systems due to their extensive roots systems and year-round ground cover. However, less is known about the extent to which perennial grain crops affect food web dynamics and soil carbon (C) cycling over time. Furthermore, many mechanistic questions remain regarding the influence of root quantity and quality on soil biological communities and C cycling function. In this study, we quantified root biomass and quality, bacterial and nematode community structure, and labile soil C pools of perennial intermediate wheatgrass [Thinopyrum intermedium (Host) Buckworth and Dewey] and annual winter wheat (Triticum aes L.) across three nitrogen (N) management systems (Organic, Low inorganic N, High inorganic N). After 4 years, the perennial grain crop had significantly greater root quantity and permanganate oxidizable carbon (POXC) relative to annual wheat. Mineralizable C was similar between the two plant systems but differed by N management. Perenniality more than management influenced nematode community structure and function; perennial grains increased the structure index (a measure of trophic complexity) by 55% compared to annual wheat. Both plant type and management influenced bacterial communities, but not until the final year of the experiment. Our findings demonstrate that established perennial grain crops increase labile soil C and support more highly structured and complex food webs relative to annual cropping systems.

The choice of plant materials is an important component of revegetation following disturbance. To determine the utility and effectiveness of various perennial grass species for revegetation on varied landscapes, a meta analysis was used to evaluate the stand establishment and persistence of 18 perennial cool-season grass species in 34 field studies in the Intermountain and Great Plains regions of the United States under monoculture conditions. Combined across the 34 studies, stand establishment values ranged from 79% to 43% and stand persistence values ranged from 70% to 0%. Intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth & D. R. Dewey), tall wheatgrass (Thinopyrum ponticum [Podp.] Z.-W. Liu & R.-C. Wang), crested wheatgrass (Agropyron spp.), Siberian wheatgrass (Agropyron fragile [Roth] P. Candargy), and meadow brome (Bromus riparius Rehmann) possessed the highest stand establishment (≥ 69%). There were no significant differences among the 12 species with the largest stand persi...

This study evaluated over 150 wheat x wheatgrass derivatives in a series of field experiments. The objective was to assess their capacity to regrow post-harvest and yield grain over successive years, and thereby identify characteristics common to the surviving breeding lines. Over the 3-year experimental period 61% of the 176 experimental entries demonstrated some capacity for post-harvest regrowth. Of 125 entries planted in the first two years of experimentation, 34% persisted to produce a second grain harvest in year 2. Three entries from 73 planted in 2008 persisted to produce grain in 3 successive years. In a subset of 87 entries that underwent cytogenetic analysis there was an association between regrowth ability and the presence of at least one whole genome equivalent (14 chromosomes) from the perennial donor species. If the wheat parent was a hexaploid (2n = 42), an entry required at least 56 chromosomes to achieve any substantial post-harvest regrowth. However, the presence of 56 chromosomes was no guarantee of a capacity to survive post-harvest. The morphology of the hybrid germplasm was highly variable for every trait assessed including grain yield, grain size, grain quality, harvest index, tiller height and head morphology; reflective of the diversity of pedigrees. Narrower kernels appeared to be associated with higher grain protein concentrations. Unextractable polymeric protein (UPP) correlates with rheological properties of the doughs; some of the experimental entries had very low UPP; the majority had high UPP suggesting useful flour, dough and baking properties. A high level of disease resistance was observed in the subset of entries tested for leaf, stem and stripe rust as well as wheat streak mosaic virus, indicating that further development of hybrid germplasm would be unlikely to pose an unacceptable disease threat to conventional cereal crops, particularly where amphiploids were deployed. The variability of the cohort and the presence of entries with desirable agronomic and grain quality attributes suggested a potential to breed and select for perennial wheat derivatives with commercially desirable characteristics. (C) 2012 Elsevier B.V. All rights reserved.

Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat (Ttricum aestivum). Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characterization and application of the genes for fungal and viral disease-resistance derived from Th. ponticum and Th. intermedium.

The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, many wheat-Thinopyrum intermedium alien chromosome lines were developed. Of them, Shannong 0095 (SN0095), a disomic substitution, has long spikes and flag-leaves, and thus may be an important genetic resource for wheat yield improvement. In order to realize its heterosis and combining ability on major yield traits, a 7 × 7 complete diallel design was made according to Griffing's Method-I. The results showed that heterosis for spike length (SPL), flag-leaf area (FLA), number of spikes per plant (NSP), number of spikelets per spike (NSL), kernels per spike (KPS), 1 000-kernel weight (TKW) and grain yield per plant (GYP) existed in all the crosses by SN0095, but heterobeltiosis occurred only for KPS, TKW, and GYP. The relative mid-parent heterosis (RMH) and relative high-parent heterosis (RHH) for GYP, which valued as high as 35.32 and 29.92% respectively, were the highest among all the traits mearsured. Though additive and non-additive gene effects and cytoplasmic effects (or cytoplasmic-nuclear interaction effects) were found in governing all the traits measured above, additive gene action played a predominant role. The results also showed that SN0095 was the best-general combiner for SPL and FLA, and high-general combiner for NSP amongst all the parents. Estimates of specific combining ability (SCA) showed that SN0095 could also make high-SCA combinations for GYP, such as SN0095 × Jimai 19 (JM19). SN0095 could be a unique and important parent in hybrid wheat breeding programs.

The aim of this study was to provide cytogenetical evidence on the behavior of chromosome 2Ai-2 from Thinopyrum intermedium in different wheat ( Triticum aestivum L.) chromosome substitution backgrounds. Five wheat-alien disomic or ditelosomic substitution lines were crossed with the common wheat variety Chinese Spring to produce the BC 1 and F 2 populations, which were tested with expressed sequence target (EST)-PCR markers specific to chromosome 2Ai-2 and genomic in situ hybridization (GISH) analysis. In the 2Ai-2(2B) substitution background, the alien chromosome or its fragment was transferred to offspring with higher ratio than the expected ratio, whereas the transmission ratios were much lower than the expectation in the 2Ai-2(2D) background. The 2Ai-2 chromosome was transferred preferentially through heterozygosis in the 2Ai-2(2B) background. Structural changes of 2Ai-2 occurred frequently in progenies, most of which were near the centromere. Compared with the short arm, the long arm of the alien chromosome was lost more frequently in the next generations. The F 2 plants with 2AS-substitution background were rare when detected with 2Ai-2S-specific EST-PCR marker(s), suggesting that the alien telosome might be lost frequently. Structural variation of the telosomic chromosome 2Ai-2S was also observed in the offspring with 2AS-substitution background. The GISH results confirmed that the EST-PCR markers can be applied in tracing the alien chromosome in wheat background.

Masticate was collected by ruminal evacuation of four steers grazing intermediate wheatgrass (Thinopyrum intermedium Host) pasture during dormant and active plant growth periods. Masticate was either lyophilized, or oven dried (60 °C) after the material was spread either 1 cm deep on two (1935 cm2) trays or spread 3 cm deep on a pan (1290 cm2). In vitro organic matter (OM) disappearance differed (P 0.10) by the drying method; however, the extent of OM and NDF digested was altered (P < 0.05) by the drying method. Current data suggest that detrimental effects may be minimized by proper handling during oven drying. Lower temperatures, as well as increasing the surface area of samples allowing for rapid drying may minimize the effect of heat damage on the digestibility of the forage.