Scholarly Work - Research Centers
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/9236
Browse
4 results
Search Results
Item Sentinel-2-based predictions of soil depth to inform water and nutrient retention strategies in dryland wheat(Elsevier BV, 2023-11) Fordyce, Simon I.; Carr, Patrick M.; Jones, Clain; Eberly, Jed O.; Sigler, W. Adam; Ewing, Stephanie; Powell, Scott L.The thickness or depth of fine-textured soil (zf) dominates water storage capacity and exerts a control on nutrient leaching in semi-arid agroecosystems. At small pixel sizes (< 1 m; ‘fine resolution’), the normalized difference vegetation index (NDVI) of cereal crops during senescence (Zadoks Growth Stages [ZGS] 90–93) offers a promising alternative to destructive sampling of zf using soil pits. However, it is unclear whether correlations between zf and NDVI exist (a) at larger pixel sizes (1–10 m; ‘intermediate resolution’) and (b) across field boundaries. The relationship of zf to NDVI of wheat (Triticum aestivum L.) was tested using images from a combination of multispectral sensors and fields in central Montana. NDVI was derived for one field using sensors of fine and intermediate spatial resolution and for three fields using intermediate resolution sensors only. Among images acquired during crop senescence, zf was correlated with NDVI (p < 0.05) independent of sensor (p = 0.22) and field (p = 0.94). The zf relationship to NDVI was highly dependent on acquisition day (p < 0.05), but only when pre-senescence (ZGS ≤ 89) images were included in the analysis. Results indicate that cereal crop NDVI of intermediate resolution can be used to characterize zf across field boundaries if image acquisition occurs during crop senescence. Based on these findings, an empirical index was derived from multi-temporal Sentinel-2 imagery to estimate zf on fields in and beyond the study area.Item Rumen microbiome response to sustained release mineral bolus supplement with low- and high-quality forages(Frontiers Media SA, 2023-06) Eberly, Jed O.; Wyffels, Samuel A.; Carlisle, Tanner J.; DelCurto, TimothyIntroduction: Limited forage quantity and quality are challenges faced in livestock production systems in semi-arid rangelands of the western United States, particularly when livestock face stressors such as cold weather or have increased nutritional requirements such as during pregnancy and lactation. To meet livestock nutrient requirements, producers frequently provide supplemental nutrition, however there is limited knowledge regarding the effects of these practices on the rumen microbiome in these environments. Methods: A study was conducted to evaluate changes in the rumen microbiome in response to high- and low- quality forage with sustained release mineral boluses. The study consisted of 16 ruminally-cannulated 2–3-year-old black angus cows fed high quality grass alfalfa hay or low-quality grass hay with a 90 or 180 day sustained release mineral bolus. Rumen samples were collected pre-feeding and 8 hours post feeding and bacterial 16S rRNA gene amplicons were sequenced from the rumen fluid. Results: Alpha diversity as measured by Shannon’s diversity index decreased significantly over time (p<0.01) and averaged 5.6 pre-feeding and 5.4 post- feeding and was not significantly different between high- and low-quality forages or between mineral bolus types (p>0.05). Principal coordinates analysis (PCoA) of the Bray-Curtis dissimilarity matrix showed distinct grouping by feed quality and time but not by mineral bolus type. Bacteroidetes and Firmicutes were the dominant phyla in all treatments and significant increases (p<0.05) in the relative abundance of the family Lachnospiraceae and the genus Prevotella were observed in high quality forage diets. Rumen VFA and NH3-N concentrations were also strongly associated with the high-quality forage diet. Predictive functional profiling indicated that functions associated with methanogenesis were negatively correlated with feed quality. Discussion: The results of this study suggest that mineral bolus type is unlikely to affect rumen bacterial community structure or function while forage quality can significantly alter community structure and predicted functions associated with methanogenesis and VFA production.Item Rumen microbiome response to sustained release mineral bolus supplement with low- and high-quality forages(Frontiers Media SA, 2023-06) Eberly, Jed O.; Wyffels, Samuel A.; Carlisle, Tanner J.; DelCurto, TimothyIntroduction: Limited forage quantity and quality are challenges faced in livestock production systems in semi-arid rangelands of the western United States, particularly when livestock face stressors such as cold weather or have increased nutritional requirements such as during pregnancy and lactation. To meet livestock nutrient requirements, producers frequently provide supplemental nutrition, however there is limited knowledge regarding the effects of these practices on the rumen microbiome in these environments. Methods: A study was conducted to evaluate changes in the rumen microbiome in response to high- and low- quality forage with sustained release mineral boluses. The study consisted of 16 ruminally-cannulated 2–3-year-old black angus cows fed high quality grass alfalfa hay or low-quality grass hay with a 90 or 180 day sustained release mineral bolus. Rumen samples were collected pre-feeding and 8 hours post feeding and bacterial 16S rRNA gene amplicons were sequenced from the rumen fluid. Results: Alpha diversity as measured by Shannon’s diversity index decreased significantly over time (p<0.01) and averaged 5.6 pre-feeding and 5.4 post- feeding and was not significantly different between high- and low-quality forages or between mineral bolus types (p>0.05). Principal coordinates analysis (PCoA) of the Bray-Curtis dissimilarity matrix showed distinct grouping by feed quality and time but not by mineral bolus type. Bacteroidetes and Firmicutes were the dominant phyla in all treatments and significant increases (p<0.05) in the relative abundance of the family Lachnospiraceae and the genus Prevotella were observed in high quality forage diets. Rumen VFA and NH3-N concentrations were also strongly associated with the high-quality forage diet. Predictive functional profiling indicated that functions associated with methanogenesis were negatively correlated with feed quality. Discussion: The results of this study suggest that mineral bolus type is unlikely to affect rumen bacterial community structure or function while forage quality can significantly alter community structure and predicted functions associated with methanogenesis and VFA production.Item Intercropping chickpea–flax for yield and disease management(Wiley, 2023-03) Zhou, Yi; Chen, Chengci; Franck, William L.; Khan, Qasim; Franck, Sooyoung; Crutcher, Frankie K.; McVay, Kent; McPhee, KevinAscochyta blight (caused by Ascochyta rabiei) is a primary concern of chickpea production worldwide. Intercropping chickpea with a non-host crop has the potential to suppress this disease and improve resource use efficiency for enhanced crop yield. This study aimed to evaluate the effects of seeding rate and row configuration of chickpea (Cicer arietinum L.)–flax (Linum usitatissimum L) intercropping on (1) yield and seed quality, (2) disease incidence and severity of Ascochyta blight of chickpea, and (3) land productivity of this intercropping system. Field trials were conducted at the Eastern Agricultural Research Center, Sidney, MT, and the Southern Agricultural Research Center, Huntley, MT, in 2020 and 2021. Chickpea was planted with flax in four intercropping configurations (70% chickpea–30% flax in mixed rows, 50% chickpea–50% flax in alternate rows, 50% chickpea–50% flax in mixed rows, and 30% chickpea–70% flax in mixed rows). Chickpea yield decreased with increased flax proportion in the mixed rows intercrop. Flax displayed higher competitiveness than chickpea, resulting in decreased yield and protein concentration in chickpea but increased yield and protein content in flax. Land equivalent ratio of intercropping was greater than one, showing improved land productivity (2%–23% greater than monocropping). Intercropping reduced Ascochyta blight disease incidence and severity; the 50% chickpea–50% flax and 30% chickpea–70% flax intercropping configurations could reduce the disease severity to 50% (in Huntley) and 67% (in Sidney) of that in the monocropping. These results indicated that seed ratio and planting configurations of chickpea–flax intercropping may be manipulated to increase land use efficiency and reduce Ascochyta blight in chickpea. Canadian Development Center ‘CDC Leader’ yielded greater than Royal in the higher disease pressure environment in Huntley indicated that selection of disease resistant cultivars is important for managing Ascochyta blight in chickpea.