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 Spring Seeding Integrated with a Spring Glyphosate Application Promotes Establishment ofPseudoroegneria spicata(bluebunch wheatgrass) inBromus tectorum(cheatgrass)-infested Rangelands(University of Wisconsin Press, 2024-08) Majeski, Michelle L.; Simanonok, Stacy C.; Miller, Zachariah; Rew, Lisa J.; Mangold, Jane M.Bromus tectorum invasion and associated impacts have been documented extensively in the western United States. Integrated approaches have been shown to be effective in restoring rangeland impacted by B. tectorum. While integrating herbicide and seeding of native species can be effective, strategic timing of these tools could further improve restoration outcomes. At three B. tectorum-infested rangeland sites in western Montana, we tested the effects of glyphosate application and timing (fall or spring) and five Pseudoroegneria spicata seeding dates (one fall and four spring dates) on density and cover of P. spicata. Pseudoroegneria spicata density was nearly ten times higher with glyphosate applied to B. tectorum compared to none at one site, and P. spicata abundance was generally greater when spring glyphosate application was combined with spring seeding at two other sites where densities ranged from six to 25 plants per m2. Overall, B. tectorum abundance was minimally affected by treatments and fluctuated between years and across study sites. Our results indicate that spring seeding of P. spicata following a spring glyphosate application promoted establishment of P. spicata, increasing its density and cover compared to fall glyphosate application and fall seeding, spring glyphosate following fall seeding, or seeding without any glyphosate. Restoration practitioners have an ecologically-based strategy for timing glyphosate application and seeding P. spicata based on our results, where spring-seeded P. spicata can grow for several months prior to fall emergence of the next B. tectorum cohort.Item Testing the effects of seed pellet composition to aid in semiarid restoration seeding(Wiley, 2024-11) Teichroew, Erin B.; Rew, Lisa J.Restoring and revegetating semiarid regions with native perennial grasses is an extremely difficult task, often unsuccessful due to harsh abiotic conditions. We conducted studies evaluating the use of seed pellets to improve restoration seeding success in controlled and field environments. In a controlled setting, we evaluated the impacts of clay volume, pellet size, and watering rate on seedling establishment and pellet disintegration. The amount of clay, size of pellets, and watering rate were varied in a full factorial design. Seedlings emerged from 40% of the pellets. Clay content did not impact seedling emergence, but larger pellets (2.5 cm) were more likely to produce seedlings. However, when smaller pellets (1.5 cm) produced seedlings, a higher proportion emerged (15 vs. 9%). In the field, we compared seedling establishment monthly, overall summer recruitment, and disintegration of seed pellets made with 10% and 55% clay to broadcast seed and a non-seeded control using a randomized design. Seedling emergence was higher for both the 10% (1.4 seedlings) and 55% clay pellets (1.0 seedling) than the control treatments (0.5 seedlings), and also higher for the 10% clay pellets than broadcast treatments (0.8 seedlings). Additionally, we found that seedling establishment and recruitment were unaffected by pellet disintegration. End-of-season recruitment was higher in 10% clay pellets (2.6 seedlings) than in 55% clay pellets (1.2 seedlings) and control treatments (1.0 seedling). We also found that 2.5 cm pellets had slightly higher recruitment, indicating that larger pellets may be more suited to seedling survival in semiarid environments.Item Organic wheat: Lessons learned and challenges remaining(Wiley, 2024-09) Carr, Patrick M.Wheat has been an important part of the human diet for millennia. The increase in demand for wheat grown organically in the United States and globally reflects the growing interest in organic food and food products. A symposium on organic wheat production was held during the annual meeting of the American Society of Agronomy in Baltimore, MD, during 2021. Presenters discussed the state-of-the-science on organic wheat research. Papers were solicited following the symposium for inclusion in this special section. As a result, five papers are included in this special section: four focus on organic wheat research in North America while one discusses results of a European study.Item A New Species of Nemozoma Latreille, 1804 (Coleoptera: Cleroidea: Trogossitidae) from the French Antilles and New Distributional Records for Nemozoma fleutiauxi Lepesme, 1947(Coleopterists Society, 2024-09) Kippenhan, Michael G.Nemozoma lepesmei Kippenhan, new species is described and illustrated from specimens collected from the islands of Montserrat and Guadeloupe in the French Antilles. This new species is compared to other West Indian species and a key to the species known to inhabit the West Indies is provided. Recent distributional records for Nemozoma fleutiauxi Lepesme, 1947 are included.Item Successful management of Stegasta bosqueella (Lepidoptera Gelechiidae) in peanut with an attract-and-kill strategy(National Institutes of Health, 2024-10) Lima Pinto, Jose Ricardo; Aparecido Fernandes, OdairBACKGROUND. Rednecked Peanutworm Stegasta bosqueella control is primarily achieved using broad spectrum insecticides targeting the larval stage. However, due to inconspicuous behavior and limited movement of the larvae within the peanut crop, foliar insecticides alone have been insufficient to reduce S. bosqueella populations. The poor effectiveness of chemical products, combined with the necessity of frequent fungicide applications, leads to an overuse of pesticides in peanuts. Given the challenges associated with targeting the larval stage, alternative strategies are needed to improve pest management. Our hypothesis was that by targeting the adult stage, the most mobile stage of the insect, we could decrease the levels of S. bosqueella damage in peanut crops while being less aggressive to the environment. RESULTS. Over 2 years, our study demonstrated that semiochemical-food-based attract and kill treatments significantly reduced the number of S. bosqueella adults captured per food-baited trap per week. This reduction was associated with fewer larvae and decreased plant damage compared to untreated control areas. To optimize this strategy, several key practices must be followed: (a) Prompt treatment application (chemical associated with attractant) should be applied upon detection of an increase in adult trap catches; (b) Timing applications to coincide with peak adult movement (6 pm to 9 pm); and (c) Applying treatments strategically on two peanut rows, 50 m apart, per hectare. CONCLUSIONS. The attract-and-kill method can effectively reduce S. bosqueella damage in peanut crops, and has the potential to target other moth species that act as peanut defoliators. © 2024 Society of Chemical Industry.Item Assessing the Effects of Surgical Irrigation Solutions on Human Neutrophil Interactions with Nascent Staphylococcus aureus Biofilms(MDPI AG, 2024-09) Gaur, Gauri; Predtechenskaya, Maria; Voyich, Jovanka M.; James, Garth; Stewart, Philip S.; Borgogna, Timothy R.Staphylococcus aureus (S. aureus) is the leading cause of surgical site infections (SSIs) and is capable of biofilm growth on implanted foreign devices. The use of surgical irrigation solutions has become a common strategy to combat bacterial contamination events that occur during surgery. Despite their antimicrobial activity, SSI rates remain consistent, suggesting that low-level contamination persists. In these cases, circulating neutrophils must traffic from the blood to contamination sites to aid in bacterial clearance. The influence of irrigation solutions on neutrophils’ ability to engage with bacteria has not been explored. The effects of three commonly used irrigation solutions: Xperience (sodium lauryl sulfate), Irrisept (chlorhexidine gluconate), and Betadine® (povidone-iodine) on nascent S. aureus biofilms alone and in the presence of human neutrophils were assessed at manufactured and diluted concentrations. All three solutions, at a 10% dilution, inhibited bacterial growth as demonstrated by culture assays and confocal video microscopy of bacterial aggregate formation. The effects of 10% dilutions of each of these solutions on neutrophil membrane integrity (by flow cytometry and propidium iodide staining) and motility (by confocal video microscopy of neutrophil track length) were investigated with differing outcomes for each irrigation solution. At this concentration only Irrisept preserved neutrophil membrane integrity and motility. Together, this study examines an overlooked aspect of surgical irrigation solutions by investigating their impact on innate immunity and highlights the feasibility of formulations wherein solution effectiveness is complemented by neutrophil function to reduce risks of infection.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.