College of Agriculture
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As the foundation of the land grant mission at Montana State University, the College of Agriculture and the Montana Agricultural Experiment Station provide instruction in traditional and innovative degree programs and conduct research on old and new challenges for Montana’s agricultural community. This integration creates opportunities for students and faculty to excel through hands-on learning, to serve through campus and community engagement, to explore unique solutions to distinct and interesting questions and to connect Montanans with the global community through research discoveries and outreach.
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Item Multiple administrations of bovine appeasing substance during a 42-day preconditioning program followed by feedlot receiving and its effects on physiologic, health, and performance responses of feeder cattle(Oxford University Press, 2024-01) Kvamme, Keenan; Marques, R. S.; Alves Cruz, Vinicius; Limede Cintra, Amaldo; Ogg, Makayla A.; McCoski, Sarah; Posbergh, Christian; Bradbery, Amanda N.; Mercadante, Vitor R. G.; Mackey, Shea; Pickett, Autumn; Cooke, Reinaldo F.This experiment evaluated the effects of multiple bovine-appeasing substance (BAS) administration during a 42-d preconditioning program followed by a feedlot receiving period on productivity, health, and physiological variables of feeder cattle. Ninety calves were weaned, weighed, loaded into a livestock trailer, transported for 70 km, and unloaded at the Bozeman Agricultural Research and Teaching Farm for a 42-d preconditioning program. Upon arrival, calf body weight (BW) was recorded again, and both pre- and post-transport BWs were averaged and used as calf weaning initial BW. Calves were ranked by BW, sex, and age in a completely randomized design and assigned to receive 1) multiple administrations of BAS at weaning (day 0), days 14, 28, and before transport and feedlot entry (day 42; BAS; RSEA Group, Quartier Salignan, France; n = 9 pens/treatment), or 2) placebo (diethylene glycol monoethyl ether; CON; n = 9 pens/treatment). Treatments (5 mL) were applied to the nuchal skin area of each animal during the preconditioning period. Calves within treatment groups were ranked again by initial BW, sex, and age, in a manner that pens have similar initial BW, age, and three steers and two heifers and allocated to 1 of the18 drylot pens. On day 42, calves were combined within the treatment group, loaded into two different single double-deck commercial livestock trailers, and transported for 1,000 km (approximately 16 h). Upon arrival (day 43), calves were unloaded at the same feedyard. Blood samples were collected on days 0, 3, 7, 14, 21, 28, 42, 43, 46, 50, 57, 64, and 90. Average daily gain, final BW, and feed efficiency did not differ (P > 0.52) between BAS and CON calves in the preconditioning and receiving phases. A treatment × day interaction was detected (P < 0.001) for plasma haptoglobin concentrations, which was greater (P < 0.01) in CON on days 3 and 7 vs. BAS calves. During the preconditioning phase, serum NEFA concentration was reduced (P < 0.01) in BAS on day 3 compared with CON calves. A treatment × day interaction was detected (P = 0.001) for exit velocity, which was greater (P < 0.001) for CON vs. BAS calves on days 3, 7, 14, and 21 during the preconditioning phase and on day 46 of the receiving phase. Therefore, Applications of BAS reduced immunological responses and exit velocity associated with stress caused by management practices, but did not improve performance during the preconditioning and receiving phases.Item Consistent time allocation fraction to vegetation green-up versus senescence across northern ecosystems despite recent climate change(American Association for the Advancement of Science, 2024-06) Meng, Fandong; Felton, Andrew J.; Mao, Jiafu; Cong, Nan; Smith, William K.; Körner, Christian; Hu, Zhongmin; Hong, Songbai; Knott, Jonathan A.; Yan, Yanzi; Guo, Bixi; Deng, Ying; Leisz, Stephen J.; Dorji, Tsechoe; Wang, Shiping; Chen, AnpingExtended growing season lengths under climatic warming suggest increased time for plant growth. However, research has focused on climatic impacts to the timing or duration of distinct phenological events. Comparatively little is known about impacts to the relative time allocation to distinct phenological events, for example, the proportion of time dedicated to leaf growth versus senescence. We use multiple satellite and ground-based observations to show that, despite recent climate change during 2001 to 2020, the ratio of time allocated to vegetation green-up over senescence has remained stable [1.27 (± 0.92)] across more than 83% of northern ecosystems. This stability is independent of changes in growing season lengths and is caused by widespread positive relationships among vegetation phenological events; longer vegetation green-up results in longer vegetation senescence. These empirical observations were also partly reproduced by 13 dynamic global vegetation models. Our work demonstrates an intrinsic biotic control to vegetation phenology that could explain the timing of vegetation senescence under climate change.Item Using an ensemble approach to predict habitat of Dusky Grouse ( Dendragapus obscurus ) in Montana, USA(Resilience Alliance, Inc., 2024-01) Leipold, Elizabeth; Gower, Claire N.; McNew, LanceDusky Grouse (Dendragapus obscurus) are an under-monitored game species in Montana and elsewhere across their distribution. Without population monitoring it is difficult to establish appropriate harvest regulations or understand the impact of environmental disturbances (e.g., timber harvest, climate change) on populations. As a first step toward developing methods for unbiased population monitoring, we must identify appropriate sampling sites, which requires knowledge of Dusky Grouse habitat. Our goal was to explore relationships between Dusky Grouse use and habitat characteristics, and then generate a state-wide map predicting Dusky Grouse habitat in Montana using two methods: resource selection functions and random forest classifiers. The Integrated Monitoring in Bird Conservation Regions program provided a multi-year dataset of Dusky Grouse observations, which we reduced to detected (n=132) and pseudo-absent (n=5960) locations, using geospatial datasets to obtain topographic and vegetation characteristics for each location. We evaluated the predictability of the two models using receiver operating characteristics and area under the curve (ROC/AUC) with k-fold cross validation and classification accuracy of an independent dataset of incidental Dusky Grouse locations. We found both models to be highly predictive and multiple habitat characteristics were found to help predict relative probability of use such as proportion of trees with a height of 16–20m and conifer forest vegetation types. We converted both models to binary values and used an ensemble (frequency histogram) approach to combine the models into a final predictive map. Consensus between the resource selection function and random forest models was high (93%) and the ensemble map had higher predictive accuracy when classifying the independent dataset than the other two models. Our results show that our ensembled model approach was able to accurately predict potential Dusky Grouse habitat and therefore can be used to delineate areas for future population monitoring of Dusky Grouse in Montana.Item Assessing the effectiveness of satellite and UAV-based remote sensing for delineating alfalfa management zones under heterogeneous rootzone soil salinity(Elsevier BV, 2024-09) Sapkota, Anish; Verdi, Amir; Scudiero, Elia; Montazar, AliSite-specific application of agricultural inputs is crucial for optimizing resource utilization in alfalfa (Medicago sativa L.) production and addressing challenges such as soil salinity. The main objective of this study was to assess the effectiveness of PlanetScope and UAV-based NDVI imagery for delineating alfalfa management zones under heterogeneous rootzone soil salinity. The research was conducted in the alfalfa field located in Imperial Valley, CA. The extent of rootzone soil salinity was assessed using Electromagnetic induction (EMI) technology and deep soil sampling. Reference management zones were then defined using the soil salinity (ECe) map derived from apparent electrical conductivity (ECa) data. Additionally, a time series of NDVI images from PlanetScope imagery and an NDVI image captured using an unmanned aerial vehicle were used to delineate remote sensing-based management zones. Laboratory analysis of disturbed soil samples collected at various depths provided soil physicochemical property data. Soil salinity of the samples ranged from 2.2 to 13.4 dS m−1 with a moderate level of variability (CV = 37.7 %). ECe-based management zones accounted for approximately 83 % of the field's variability and exhibited substantial differentiation among delineated zones concerning diverse soil properties, including ECa, ECe, gravimetric water content, Mg2+, boron, Ca2+, Na+, and Cl−. Notably, NDVI images effectively captured field variability on par with ECe-based zoning. Moreover, NDVI images recommended the same optimal number of zones (i.e., three) to address the field's variability, aligning with the ECe-based zoning approach. Our findings highlight that heterogeneity of soil salinity in the root zone primarily impacts the variability of alfalfa NDVI early in the growing season. Consequently, this early stage emerges as the most opportune timeframe for NDVI-based zoning for rapid assessment of rootzone soil salinity concerns.Item The Grain Number Increase 1 alleles GNI‐A1‐105Y and ‐105K increase grain number in spring wheat(Wiley, 2024-05) Hale, Caleb; Tillet, Brandon J.; Martin, John M.; Hogg, Andrew C.; Cook, Jason P.; Giroux, Michael J.Wheat (Triticum aestivum L.) has inflorescences made up of multiple spikelets arranged along a central rachis, with each spikelet producing between one and four grains. The Grain Number Increase 1 (GNI-A1) gene wheat directly influences grain number per spikelet and grain size. Three naturally occurring alleles have been described previously: GNI-A1-105N, 105Y, and 105K. This project's goal was to characterize the impact of these alleles within hard red spring wheat cultivars in Montana, where each of the alleles is common. The 105N allele and the 105K allele were compared through analysis of an F5 Vida by Spring-Yellowstone recombinant inbred line (RIL) population, and with near isogenic lines (NILs) derived from the same population. The 105N allele and the 105Y allele were compared with NILs derived from an F4 Lanning by Egan RIL population. We analyzed the impact of each of the three alleles and compared their effects on inflorescence architecture, grain size, grain yield, grain quality, and milling quality under Bozeman, MT, field conditions. Data show that either loss-of-function alleles (105Y and 105K) increased grain number per spikelet by 5% when compared to the more functional allele (105N) across all years and environments tested. Overall grain size was not significantly reduced and there was also not a significant increase in overall grain yield.Item Functional attributes of conifers expanding into temperate semi-arid grasslands modulate carbon and nitrogen fluxes in response to prescribed fire(Springer Science and Business Media LLC, 2024) Gay, Justin D.; Currey, Bryce; Davis, Kimberley T.; Brookshire, E. N. JackFire exclusion is a key factor driving conifer expansion into temperate semi-arid grasslands. However, it remains unclear how reintroducing fire affects the aboveground storage of carbon (C) and nitrogen (N) in the expanding tree species and belowground in soils. To assess the impacts of fire reintroduction C and N pools and fluxes in areas of conifer expansion we targeted a region of the Northern Great Plains that has experienced extensive woody plant expansion (WPE) of two species: ponderosa pine (Pinus ponderosa) and juniper (Juniperus spp). We quantified tree mortality of both species to estimate the amount of dead biomass C and N produced by a recent prescribed fire, in addition to changes in soil C, pyrogenic C (PyC), and N concentrations across a woody-cover gradient using a before/after/control experimental design. Post-fire soil chemical analysis revealed a 2 year increase in mineral soil C, PyC and N, suggesting the return of fire led to the transfer of partially combusted plant organic matter back to the soil. Further, we found that functional trait differences between the two species influenced the distribution of living conifer biomass-N prior to fire. Despite junipers having 41% less total aboveground biomass than ponderosa, they contained two times more aboveground N. Prescribed fire resulted in 88% mortality of all mature juniper stems and increased fire severity correlated with greater pre-fire juniper cover. Ponderosa mortality varied by size class, with > 40 cm stem diameter class having only 28% mortality. High mortality and greater aboveground N storage in juniper biomass, compared to ponderosa, led to 77% of the total conifer biomass N lost. Consequently, the functional attributes of expanding trees differentially contribute to fluxes of C and N after the return of fire, with junipers acting as conduits for N movement due to their relatively higher N content in less fire-resistant tissues and ponderosa serving as important and more stable storage pools for C. Together, these findings highlight the importance of considering species-specific traits when planning WPE management strrategies at landscape-scales, particularly when goals include C storage or soil nutrient status.Item Optimizing crop seeding rates on organic grain farms using on farm precision experimentation(Elsevier BV, 2024-09) Loewen, Sasha; Maxwell, Bruce D.Organic agriculture is often regarded as less damaging to the environment than conventional agriculture, though at the expense of lower yields. Field-specific precision agriculture may benefit organic production practices given the inherent need of organic farmers to understand spatiotemporal variation on large-scale fields. Here the primary research question is whether on-farm precision experimentation (OFPE) can be used as an adaptive management methodology to efficiently maximize farmer net returns using variable cover crop and cash crop seeding rates. Inputs of cash crop seed and previous-year green manure cover crop seed were experimentally varied on five different farms across the Northern Great Plains from 2019 to 2022. Experiments provided data to model the crop yield response, and subsequently net return, in response to input (seeding) rates plus a suite of other spatially explicit data from satellite sources. New, field-specific spatially explicit optimum input rates were generated to maximize net return including temporal variation in economic variables. Inputs were spatially optimized and using simulations it was found that the optimization strategies consistently out-performed other strategies by reducing inputs and increasing yields, particularly for non-tillering crops. By adopting site specific management, the average increase in net return for all fields was $50 ha−1. These results showed that precision agriculture technologies and remote sensing can be utilized to provide organic farmers powerful adaptive management tools with a focus on within-field spatial variability in response to primary input drivers of economic return. Continued OFPE for seeding rate optimization will allow quantification of temporal variability and subsequent probabilistic recommendations.Item Alternative sources of molybdenum for Methanococcus maripaludis and their implication for the evolution of molybdoenzymes(Springer Science and Business Media LLC, 2024-10) Payne, Devon; Keller, Lisa M.; Larson, James; Bothner, Brian; Colman, Daniel; Boyd, Eric S.Molybdoenzymes are essential in global nitrogen, carbon, and sulfur cycling. To date, the only known bioavailable source of molybdenum (Mo) is molybdate. However, in the sulfidic and anoxic (euxinic) habitats that predominate in modern subsurface environments and that were pervasive prior to Earth’s widespread oxygenation, Mo occurs as soluble tetrathiomolybdate ion and molybdenite mineral that is not known to be bioavailable. This presents a paradox for how organisms obtain Mo to support molybdoenzymes in these environments. Here, we show that tetrathiomolybdate and molybdenite sustain the high Mo demand of a model anaerobic methanogen, Methanococcus maripaludis, grown via Mo-dependent formate dehydrogenase, formylmethanofuran dehydrogenase, and nitrogenase. Cells grown with tetrathiomolybdate and molybdenite have similar growth kinetics, Mo content, and transcript levels of proteins involved in Mo transport and cofactor biosynthesis when compared to those grown with molybdate, implying similar mechanisms of transport and cofactor biosynthesis. These results help to reconcile the paradox of how Mo is acquired in modern and ancient anaerobes and provide new insight into how molybdoenzymes could have evolved prior to Earth’s oxygenation.Item Short Communication: artificially reared ewes cannot be distinguished from natural reared ewes based on observed maternal behavior or lamb weaning weights(Oxford University Press, 2024-09) Posbergh, Christian J.; Miles, Asha M.; Pettifor, Natasha L.; Thonney, Michael L.Artificially rearing lambs is an important component of United States sheep production as some flocks select for increasing litter size to boost productivity. However, there is a conception among shepherds that artificially reared ewe lambs will ultimately result in poor mothers since they were not naturally raised. The objective of this study was to determine if differences in maternal behavior could be detected between ewes raised artificially and those raised naturally and if dam rearing type had an impact on lamb growth performance. Forty-eight ewes were enrolled comprised of 4 equal sized groups: artificially reared primiparous, naturally reared primiparous, artificially reared multi-parous, and naturally reared multi-parous. Ewes were observed using remote cameras to record maternal behaviors toward the lambs during and shortly after parturition. Behavior of 29 ewes during the first hour after parturition was analyzed. Independent multivariable regression models were evaluated for: proportion of time spent grooming, proportion of time spent helping the lambs nurse, number of helpful bouts, and the number of negative bouts. No statistically significant difference (P < 0.05) was detected between artificially reared and naturally reared ewes for the proportion of time spent grooming and the proportion of time spent helping the lambs nurse. Historical flock data were utilized to evaluate lamb growth between artificially and naturally reared ewes. No detrimental associations between artificially reared ewes and lamb weaning weights were observed. This study shows that artificially reared ewes are no different in terms of mothering behaviors and may be used as potential replacement candidates.Item Multitemporal Hyperspectral Characterization of Wheat Infested by Wheat Stem Sawfly, Cephus cinctus Norton(MDPI AG, 2024-09) Ermatinger, Lochlin S.; Powell, Scott L.; Peterson, Robert K.D.; Weaver, David K.Wheat (Triticum aestivum L.) production in the Northern Great Plains of North America has been challenged by wheat stem sawfly (WSS), Cephus cinctus Norton, for a century. Damaging WSS populations have increased, highlighting the need for reliable surveys. Remote sensing (RS) can be used to correlate reflectance measurements with nuanced phenomena like cryptic insect infestations within plants, yet little has been done with WSS. To evaluate interactions between WSS-infested wheat and spectral reflectance, we grew wheat plants in a controlled environment, experimentally infested them with WSS and recorded weekly hyperspectral measurements (350–2500 nm) of the canopies from prior to the introduction of WSS to full senescence. To assess the relationships between WSS infestation and wheat reflectance, we employed sparse multiway partial least squares regression (N-PLS), which models multidimensional covariance structures inherent in multitemporal hyperspectral datasets. Multitemporal hyperspectral measurements of wheat canopies modeled with sparse N-PLS accurately estimated the proportion of WSS-infested stems (R2 = 0.683, RMSE = 13.5%). The shortwave-infrared (1289–1380 nm) and near-infrared (942–979 nm) spectral regions were the most important in estimating infestation, likely due to internal feeding that decreases plant-water content. Measurements from all time points were important, suggesting aerial RS of WSS in the field should incorporate the visible through shortwave spectra collected from the beginning of WSS emergence at least weekly until the crop reaches senescence.