U.S. Dairy Forage Research Center

Abstract Forage legumes provide a wide range of ecosystem services to grasslands. Improving legume proportion and species diversity of meadow fescue [ Lolium pratense (Huds.) Darbysh] pasture‐based systems can increase the sustainability of a given farming system. This study compared no‐till or frost‐seeding methods to incorporate clovers ( Trifolium spp.) or chicory ( Cichorium intybus L.) into an established meadow fescue sward as pasture‐improvement strategies. No‐till planting occurred in the fall or spring of 2022 and 2023, and frost seeding occurred during the winter of each year. In addition, this study aimed to quantify biological N 2 fixation (BNF) from the interseeded clovers. Chicory failed to establish in both years of the study, comprising less than 2% of the botanical composition. While no‐till planting in the fall or spring, or frost seeding during the winter were successful at establishing clovers, frost seeding may be a more attractive method provided that it may be more economical, requiring less specialized equipment. No‐till interseeding in the fall or spring are also adequate strategies. Overall, red clover ( Trifolium pratense L.) was more productive than white clover ( Trifolium repens L.) in the first year after planting. Further evaluations into persistence after the first year of clover planting are warranted. As a whole, interseeding clovers into meadow fescue pastures is indeed valuable for improving pasture systems by increasing forage accumulation and fixing up to 20 kg N ha −1 year −1 .

Microwave heating of certain foods (e.g., popcorn) can produce an expanded, puffed structure. During certain baking conditions, some cheeses (e.g., mozzarella) can form expanded structures (e.g., blisters on pizza). However, Cheddar cheese usually melts during heating instead of expanding. Our hypothesis is that by altering the proportions of moisture, protein, and fat content in cheese by drying, perhaps we can achieve a cheese composition or texture more favorable to expansion (i.e., less meltable) during microwave heating. A licensed Wisconsin cheesemaker made 4 batches (n = 4) of Cheddar cheese over a 90-d period. Cylinders (9 mm in height × 13 mm in diameter) were cut from the cheese at 7, 14, 30, 90, and 180 d of age during ripening at 4°C. These cylinders were dried for various periods in a Parmesan drying room (15.5°C, 70% relative humidity, ~10 m3/min air flow) to make partially dried cheeses with target moisture contents of 20%, 16%, and 12% (and thus, protein contents of 31.2%, 32.9%, and 34.3%, respectively). During heating, none of the partially dried cheese samples melted (loss tangent values <1) when measured with small-strain oscillatory rheology. The partially dried cheeses were heated in a homestyle 900-W microwave oven (35-75 s at 100% power) to attain expanded puffs with ~1.4% moisture and ~0.2 water activity. A split-plot design was used to analyze the impact of the age of the cheese, composition, and their interactions on the properties of the puffs. At 7 d of cheese age, puffs made from cheeses dried to 20% moisture expanded the most, and puffs made from cheeses dried to 12% moisture expanded the least. For cheeses dried to 20% moisture, puff expansion (%) decreased as the age of the cheese (before expansion) increased. Puff texture was assessed by trained sensory panelists (n = 8-10) using a 15-point quantitative descriptive analysis scale and a texture analyzer equipped with an acoustic detector. Sensory hardness and crunchiness of the puffs increased as the moisture content of the dried cheese decreased from 20% to 12%, whereas the quantity of force and sound peaks decreased. Puffs made from cheese dried to 12% moisture achieved higher acoustic peaks (~90 dB) than puffs made from cheese dried to 20% moisture (~80 dB). Scanning electron micrographs of the puffed cheeses indicated well-defined strands of protein were observed in puffs made from cheeses dried to 16% and 12% moisture. All partially dried cheeses expanded during microwave heating. We have demonstrated a novel way of making puffed snacks from Cheddar cheese. In our system, increasing the ripening time of cheese and decreasing the moisture content of the dried cheese (which caused a concomitant increase in the protein content) decreased the expansion of the puffs.

Red crown rot (RCR) of soybean, caused by Calonectria ilicicola, is new to the Midwest region of the United States, first identified in 2018 in western Illinois, and later in the neighboring states of Kentucky (2021), Indiana (2022) and Missouri (2024). Illinois has seen the most reported cases-various fields in 34 counties as of the end of the 2024 growing season. To determine the diversity and spread of C. ilicicola in Illinois, RCR-symptomatic soybean plants were collected across 44 fields from 18 Illinois counties and 79 C. ilicicola isolates were purified from lower stems. To examine the genetic diversity of these isolates, seven genetic regions were targeted for PCR amplicon sequence comparisons. The DNA sequences of the amplicons from act, cmdA, his3, tef1 and tub2 were identical to all. However, the ITS and IGS amplicons each revealed one single nucleotide polymorphism (SNP). Additionally, the PCR amplicon sequences were compared to amplicons from historical isolates collected between 1970 and 1988 in the Southeastern United States from peanut, blueberry, and soybean hosts. Sequence polymorphisms were found for all PCR amplicons (except cmdA) from the Southeastern U.S. isolates compared to the Illinois isolates, and these amplicon sequences were identical in all Southeastern U.S. isolates regardless of collection location or year. These results show that Illinois isolates collected from 2018 to 2024 showed low diversity and are most likely not due to the spread of the isolate(s) previously found in the Southeastern U.S.

Capsule shattering in sesame is a major agronomic constraint that reduces yield stability and limits mechanized harvesting efficiency. To address this challenge, 200 genetically diverse sesame genotypes from Sudan were genotyped using genotyping-by-sequencing (GBS) and evaluated for three consecutive seasons under field conditions for shattering type (ST), type of capsule beak (TCB), and bicarpellate capsule shape (BS). The resulting phenotypic and genotypic data were integrated into a multi-model genome-wide association study (GWAS) framework (BLINK, FarmCPU, and MLMM) to elucidate the genetic architecture of capsule-shattering traits. Two marker-trait associations (MTAs) were consistently identified across the GWAS models, comprising Chr1_19419575 associated with the TCB and Chr2_15649330 linked to ST. Additional MTAs, including Chr8_31466064 for ST and Chr8_19392181 and Chr8_30292484 for TCB, were also detected in this study, further highlighting the complex genetic regulation of capsule traits. Allelic effect analysis further validated the functional role of key allelic variants at Chr2_15649330 and Chr8_31466064, demonstrating significant differences in shattering responses among genotypic subgroups. In silico functional enrichment analysis using a candidate gene approach identified 68 homologous genes associated with pod shattering in Brassica napus, of which FLZ3, RZF1, MKK5, and COR27 showed distinct expression patterns that correlated with shattering susceptibility during pod development. These results provide new insights into the genetic regulation of capsule shattering, providing valuable targets for marker-assisted selection and development of sesame cultivars with enhanced resistance to shattering.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00122-026-05151-7.

This study evaluated the impact of high-energy (HE) or low-energy (LE) diets during late lactation and the responsiveness of body condition changes to diet during the dietary treatment period. Sixty-six multiparous Holstein cows were blocked by parity and expected date of parturition and randomly assigned to HE (1.74 Mcal/kg DM) or LE (1.50 Mcal/kg DM) diets at 150 d of gestation to achieve high or average BCS by dry-off (233 d of gestation). Surprisingly, not all cows within dietary treatment groups were responsive to the diet based on BCS at dry-off. To determine the underlying physiology responsible for this observation, we classified cows as responsive (R) or nonresponsive to diet (NR) within each dietary treatment: HE (HE-R, >0.25 increase in BCS [28/35]; HE-NR, ≤0.25 BCS [7/35]) or LE (LE-R ≤0.25 increase in BCS [27/31]; LE-NR >0.25 BCS increase [4/31]). Feed intake did not differ within the HE-R and HE-NR subgroups or between the LE-R and LE-NR subgroups. During the dietary treatment period, cumulative ECM was greater in HE-NR than HE-R cows (3,304 vs. 2,236 ± 151 kg). In contrast, LE-NR produced less ECM than LE-R cows (1,622 ± 229 vs. 2,068 ± 77 kg) during the dietary treatment period. Circulating insulin concentrations were similar among subgroups at study enrollment (9.2 ± 1.1 mU/mL); however, dry-off insulin concentrations differed among subgroups (HE-R 17 ± 3.0; HE-NR 5.4 ± 2.0 mU/mL; LE-R 10.2 ± 2.0; LE-NR 23.6 ± 4.0 mU/mL). One week before parturition, circulating insulin concentrations converged and were no longer different among subgroups, averaging 12.5 ± 2 mU/mL. Our data suggest that circulating insulin concentration is involved in regulating the response to dietary treatment during late lactation.

Alfalfa (Medicago sativa) has a high nutritional value, but poor digestibility of the stems limits its value as an energy source in ruminant diets. Xylan and lignin negatively impact cell wall digestibility, whereas pectins have high digestibility in the rumen. In plants, UDP-xylose synthase (UXS) catalyzes the decarboxylation of UDP-glucuronic acid to form UDP-xylose in an irreversible step that is key for xylan synthesis. We functionally characterized two UXS genes in alfalfa (MsaUXS2 and MsaUXS4) and investigated their impact on ruminal digestibility. Both genes are more highly expressed in stems than leaves, and the enzymes have UDP-glucuronic acid decarboxylase activity in vitro. Silencing MsaUXS2/MsaUXS4 via RNAi altered plant growth and resulted in a 40% decrease in xylose, a 115% increase in arabinose, and a 60% increase in galacturonic acid in the polysaccharide matrix as well as a 20% decrease in lignin in the cell wall. Together, our data show a major role for MsaUXS2 and MsaUXS4 in xylan synthesis and secondary cell wall deposition in alfalfa. Additionally, silenced lines had on average 30% increased gas production at 24 h in in vitro rumen digestibility assays, demonstrating the potential of targeting UXS genes to increase stem digestibility.

Genomic selection (GS) can accelerate plant breeding gains by reducing breeding cycle times, reducing phenotyping costs, or improving selection accuracy. GS is especially promising for perennial crops such as intermediate wheatgrass (IWG, Thinopyrum intermedium) that may require multiple years of evaluation under phenotypic recurrent selection. A major obstacle in implementing GS is the need for an affordable, high-density, genetic marker system that is scalable to thousands or tens-of-thousands of samples in breeding programs, especially in emerging or minor crop species. As sequencing costs continue to decrease, low-coverage whole genome skim-sequencing (skim-seq) has become an attractive method for GS. Using commercial laboratory products and open-source software, we implemented whole genome prediction at breeding program scale using ultra-low coverage (0.01x- 0.05x, 100-125 million reads per sample) whole genome skim-seq. Using STITCH (Sequencing to Imputation Through Constructing Haplotypes) imputation software, we evaluated optimization of imputation parameters including sequence coverage and number of assumed ancestral haplotypes. Finally, we evaluated whole genome prediction cross-validation accuracies using reduced representation genotyping-by-sequencing (GBS) versus skim-seq data for IWG, an outcrossing, heterozygous, large genome (12.7 Gb), polyploid perennial species. Our results indicate correlations between cross-validation accuracies across five traits in IWG using skim-seq data (r=0.29-0.61) can be used as effectively as GBS (r=0.29-0.55) while generating low-coverage archival sequence data that will be robust to technological advances. These methods will be applicable to a wide range of crops and scale to breeding program size, allowing for more tractable implementation of GS within breeding programs.

Dairy manure is an important nitrogen (N) source for crops, but its role in greenhouse gas (GHG) emissions and farm sustainability is not fully understood. We evaluated the effects of application of two dairy manure sources (bedded pack heifer, BP, and separated dairy solids, SDS) on corn silage yield and GHG emissions (carbon dioxide, CO2; methane, CH4; nitrous oxide, N2O) compared to a urea-fertilizer-only control (80 kg N ha−1 yr−1). The BP and SDS were applied at 18.4 and 19.4 Mg dry matter ha−1 in fall 2020 in the final year of ryegrass production. No-till corn was planted from 2021 to 2023, and GHG emissions were measured each season (from May to November). The results showed significantly greater CO2-C emissions for BP in 2021 and no differences in 2022 or 2023. A small N2O-N emission increase for BP occurred in the spring after application; however, seasonal fluxes were low or negative. Mean CH4-C emissions ranged from 2 to 7 kg ha−1 yr−1 with no treatment differences. Lack of soil aeration appeared to be an important factor affecting seasonal N2O-N and CH4-C emissions. The results suggest that GHG models should account for field-level nutrient management factors in addition to soil aeration status.

Reduced consumption of animal-sourced food (ASF) has been recommended for environmental and human health objectives; however, ASF can be important for food security and diet affordability. We explored country-level relationships among various metrics of food supply, socioeconomic context, food security, diet affordability, and agricultural greenhouse gas emissions (GHGe) to characterize how optimal inclusion ranges for ASF vary with socioeconomic factors and food system goals. Data from 2015 to 2022 for 153 countries were sourced to generate Bayesian Networks representing relationships among the studied food system metrics. Networks were used in simulations to characterize optimal ASF inclusion to achieve environmental, food security, or diet affordability goals based on individual country data. Results are most appropriately interpreted in aggregate rather than as representations of specific countries due in large part to data limitations. Across countries simulated, median total ASF inclusion in the food supply to support food security, GHGe, or affordability objectives was 18.2% ± 12.1%, 11.9% ± 6.8%, and 17.6% ± 8.5%, respectively. Joint optimization for these goals resulted in median ASF inclusion of 15.1% ± 7.2%, with notable regional differences. Although ASF increases were supported in most developing regions, decreases were supported in developed countries. The reported SD in optimal ASF inclusion were considerable, and represented between-country variation. Empirical relationships of food categories to goals consistently favored dairy and egg products over meats. These results support previous literature highlighting the environmental intensity of ASF, but also indicate that moderate ASF supplies contribute to multiple food system goals simultaneously.