Agronomy and Crop Sciences Commons^™

Pestfacts Wa Issue 01 - April 2022, Cindy L. Webster, Svetlana Micic, Saleh Adnan, Janette Pratt, Jean Galloway, Adam H. Sparks, Jeff Russell

PestFacts WA

PestFacts WA Issue 01 - April 2022 contents:

• What to expect from mollusc pests after a hot dry summer
• Meet our new team member – Dr Saleh Adnan
• Canola blackleg risk forecasts
• Have you checked out the new Grains Farm Biosecurity website?

Drivers And Barriers Of The Transition To Regenerative Agriculture Within The Eu’S Common Agricultural Policy Reform: Comparative Analysis With The Us Farm Bill, Samantha Gish

Independent Study Project (ISP) Collection

In the wake of multiple crises, such as climate change and international conflict, there is increased urgency to ensure a stable food system. Additionally, changing priorities of citizens have fostered the desire for sustainable production of food. One innovative method of food production is regenerative agriculture and in this practice the main goals are to increase system resilience, improve soil and sequester carbon. This is done through practices such as no tilling, cover and intercropping, and incorporation of livestock into crop fields. Although great in theory, these practices go against traditional agricultural practices and therefore the policy currently in place …

Evaluating Traits Influencing Hybrid Wheat Seed Production Using A Double Haploid Population Derived From Freeman × Camelot, Emre Karahan

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Hybrid wheat (Triticum aestivum L.) cultivars are preferred for their advanced agronomic traits such as a yield improvement increase up to 20%. However, hybrid cultivars remain difficult to produce on a commercial scale due to inadequate pollen dispersal, the closed nature of the wheat floret and the high cost of inducing sterility or restoring fertility in cleistogamous wheat. Redesigning parent-specific traits and understanding their potential interactions with related agronomic traits are needed to breed improved male lines in hybrid seed production fields. To better understand the genetic control of anther extrusion (AE), 174 double haploid lines derived from Freeman …

Cattle Diet Selection During The Growing Season On Upland Sandhills Rangelands, Alejandro Orozco-Lopez

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The Sandhills is a diverse and complex ecosystem comprised of different topographic positions (i.e. slopes and interdunes) that influence grazing distribution, plant species composition, and cattle diet selection. The first objective of this study was to evaluate how grazing intensity influences species composition on slopes and interdunes on native rangeland within the Hillside pasture (160 ha) at the UNL Gudmundsen Sandhill’s Laboratory (GSL). The second objective of this study was to evaluate forage quality of individual species from three plant functional groups (i.e. warm-season grasses, cool-season grasses, and forbs/shrubs) on native rangeland within the Hillside pasture (160 ha) at GSL. …

Fine Mapping And Cloning Of The Major Seed Protein Quantitative Trait Loci On Soybean Chromosome 20, Christina E. Fliege, Russell A. Ward, Pamela Vogel, Hanh Nguyen, Truyen Quach, Ming Guo, João Paulo Gomes Viana, Lucas Borges Dos Santos, James Specht, Thomas Clemente, Matthew E. Hudson, Brian W. Diers

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is a unique crop species because it has high levels of both protein and oil in its seed. Of the many quantitative trait loci (QTL) controlling soybean seed protein content, alleles of the cqSeed protein-003 QTL on chromosome 20 exert the greatest additive effect. The high-protein allele exists in both cultivated and wild soybean (Glycine soja Siebold & Zucc.) germplasm. Our objective was to fine map this QTL to enable positional-based cloning of its underlying causative gene(s). Fine mapping was achieved by developing and testing a series of populations in which the chromosomal region surrounding …

Microbiome Variation Across Populations Of Desert Halophyte Zygophyllum Qatarensis, Abdul Latif Khan, Lucas Dantas Lopes, Saqib Bilal, Sajjad Asaf, Kerri M. Crawford, Venkatesh Balan, Ahmed Al-Rawahi, Ahmed Al-Harrasi, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Microbial symbionts play a significant role in plant health and stress tolerance. However, few studies exist that address rare species of core-microbiome function during abiotic stress. In the current study, we compared the microbiome composition of succulent dwarf shrub halophyte Zygophyllum qatarensis Hadidi across desert populations. The results showed that rhizospheric and endosphere microbiome greatly varied due to soil texture (sandy and gravel). No specific bacterial amplicon sequence variants were observed in the core-microbiome of bulk soil and rhizosphere, however, bacterial genus Alcaligenes and fungal genus Acidea were abundantly distributed across root and shoot endospheres. We also analyzed major nutrients …

Microbiome Variation Across Populations Of Desert Halophyte Zygophyllum Qatarensis, Abdul Latif Khan, Lucas Dantas Lopes, Saqib Bilal, Sajjad Asaf, Kerri M. Crawford, Venkatesh Balan, Ahmed Al-Rawahi, Ahmed Al-Harrasi, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Microbial symbionts play a significant role in plant health and stress tolerance. However, few studies exist that address rare species of core-microbiome function during abiotic stress. In the current study, we compared the microbiome composition of succulent dwarf shrub halophyte Zygophyllum qatarensis Hadidi across desert populations. The results showed that rhizospheric and endosphere microbiome greatly varied due to soil texture (sandy and gravel). No specific bacterial amplicon sequence variants were observed in the core-microbiome of bulk soil and rhizosphere, however, bacterial genus Alcaligenes and fungal genus Acidea were abundantly distributed across root and shoot endospheres. We also analyzed major nutrients …

Extreme Development Of Dragon Fruit Agriculture With Nighttime Lighting In Southern Vietnam, Shenyue Jia, Son V. Nghiem, Seung-Hee Kim, Laura Krauser, Andrea E. Gaughan, Forest R. Stevens, Menas Kafatos, Khanh D. Ngo

Institute for ECHO Faculty Books and Book Chapters

Dragon fruit is widely grown in Southeast Asia and other tropical or subtropical regions. As a high-value cash crop ideal for exportation, dragon fruit cultivation has boomed during the past decade in southern Vietnam. Light supplementing during the winter months using artificial lighting sources is a widely adopted cultivation technique to boost productivity in the major dragon fruit planting regions of Vietnam. The application of electric lighting at night leads to a significant increase of nighttime light (NTL) observable by satellite sensors. The strong seasonality signal of NTL in dragon fruit cultivation enables identifying dragon fruit plantations using NTL images. …

A Global Soil Spectral Calibration Library And Estimation Service, Keith D. Sheperd, Rich Ferguson, David Hoover, Fenny Van Egmond, Jonathan Sanderman, Yufeng Ge

Department of Agronomy and Horticulture: Faculty Publications

There is growing global interest in the potential for soil reflectance spectroscopy to fill an urgent need for more data on soil properties for improved decision-making on soil security at local to global scales. This is driven by the capability of soil spectroscopy to estimate a wide range of soil properties from a rapid, inexpensive, and highly reproducible measurement using only light. However, several obstacles are preventing wider adoption of soil spectroscopy. The biggest obstacles are the large variation in the soil analytical methods and operating procedures used in different laboratories, poor reproducibility of analyses within and amongst laboratories and …

Southeast Asia Must Narrow Down The Yield Gap To Continue To Be A Major Rice Bowl, Shen Yuan, Alexander M. Stuart, Alice G. Laborte, Juan I. Rattalino Edreira, Achim Dobermann, Le Vu Ngoc Kien, Lưu Thị Thúy, Kritkamol Paothong, Prachya Traesang, Khin Myo Tint, Su Su San, Marcelino Q. Villafuerte Ii, Emma D. Quicho, Anny Ruth P. Pame, Rathmuny Then, Rica Joy Flor, Neak Thon, Fahmuddin Agus, Nurwulan Agustiani, Nanyan Deng, Tao Li, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Southeast Asia is a major rice-producing region with a high level of internal consumption and accounting for 40% of global rice exports. Limited land resources, climate change and yield stagnation during recent years have once again raised concerns about the capacity of the region to remain as a large net exporter. Here we use a modelling approach to map rice yield gaps and assess production potential and net exports by 2040. We find that the average yield gap represents 48% of the yield potential estimate for the region, but there are substantial differences among countries. Exploitable yield gaps are relatively …

Editorial: Genomics-Enabled Triticeae Improvement, Xue-Feng Ma, Xianchun Xia, Shuyu Liu, P. Stephen Baenziger, Hakan Özkan

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Application Of Pheromone Is Potential Ecological Approach In Management Of Tuta Absoluta In Tomatoes: The Case Of Ruaha River Basin In Iringa, Tanzania, Theonest Kombe, Nicodemus D. Matojo, Fikira Kimbokota

Journal of Humanities and Social Sciences

Tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is currently considered to be one of the most destructive insect pests of tomatoes worldwide. The present study was conducted in three study sites along Ruaha River Basin, Iringa, Tanzania, to assess community awareness about T. absoluta infestation and its management. The study also evaluated the susceptibility of three tomato varieties against T. absoluta in a greenhouse setting, as well as the effect of colours of traps and doses of pheromone in attracting T. absoluta in a field environment. The field survey revealed that 97% of the respondents were aware of the …

Influence Of Fertilizer Rate On Swollen Stem Formation (“Bulbing”) And Vitamin C Content In Different Kohlrabi Cultivars, Mark Iradukunda, Paul E. Read

Honors Program: Senior Projects (Public)

Kohlrabi (Brassica oleracea Gongylodes Group) is a vegetable crop found in the Brassicaceae, and it is rich in antioxidants such as vitamin C. Vitamin C helps in oxidative damage repair and strengthens the immune system, so exploring vitamin C sources may contribute to improving human health. The objective of this study was to determine the effect of different fertilizer rates on kohlrabi yield, in terms of the swollen stem and the vitamin C content, and if those effects are similar in different kohlrabi cultivars. In this greenhouse study, we fertilized four potted kohlrabi cultivars with a common water-soluble greenhouse fertilizer …

No-Till Farming And Greenhouse Gas Fluxes: Insights From Literature And Experimental Data, S. J. Ruis, H. Blanco-Canqui, P. J. Jasa, V. L. Jin

Department of Agronomy and Horticulture: Faculty Publications

Tillage intensity may differently impact gaseous losses of C and N to the atmosphere, but data from long-term experiments are relatively few. Yet, this information is needed to better understand C and N losses and gains in agricultural systems. The objective of this study was to determine how tillage intensity affects soil greenhouse gas (GHG) fluxes (CO₂, N₂O, and CH₄) by comparing experimental data from moldboard plow (MP), chisel plow (CP), double disk (DD), and no-till (NT) soils after 38–40 yr of management in a rainfed corn (Zea mays L.)- soybean (Glycine …

Modeling The Dynamics Of Soil Organic Matter Accumulation From Leaf Litterfall As Affected By Tillage Practices In Mango Orchard, Fernan T. Fiegalan, Cherry L. Ringor, Tolentino B. Moya

The Philippine Agricultural Scientist

This study was undertaken to determine long-term soil organic matter (SOM) accumulation dynamics from added mango leaf litter (MLL) into tilled (MT) and non-tilled soil (MnT) through integrated field experiment (bio-physico-chemical edaphic properties) and system dynamics modeling. Field data shows that the coarse (Lf) and fine (Fn) fractions of SOM have no significant difference (p > 0.05) between MT and MnT during the dry season. In contrast, there is a significant difference (p < 0.01) in the Fn fraction between MT and MnT during the wet season. The total N, available P, exchangeable K, as well as the collembola, bacteria, and fungi in the soil were also assessed. Of these parameters, the available P and exchangeable K have a significant difference between the MnT and MT during the dry season. In comparison, the total N and collembola significantly differed during the wet season. The results of the field experiment were used in the parametrization to build the SOM accumulation model. The 20-year simulation showed that the incorporation of MLL into the soil through tillage increased SOM from 3.09% to 3.13%, with an average of 2.78 ± 0.018%. In the non-tilled orchard, SOM also increased from 3.09% to 4.23%, with an average of 3.59 ± 0.035%. This SOM level can sustain the fertility and productivity of the mango agroecosystem. The increase in SOM is accounted for by the coarse fraction both in tilled and non-tilled plots. Given the foregoing, with minimum tillage, mango orchards can be developed into crop-based systems.

Hybrid Seed Set In Relation With Male Floral Traits, Estimation Of Heterosis And Combining Abilities For Yield And Its Components In Wheat (Triticum Aestivum L.), Samira El Hanafi, Souad Cherkaoui, Zakaria Kehel, Miguel Sanchez-Garcia, Jean-Benoit Sarazin, Stephen Baenziger, Wuletaw Tadesse

Department of Agronomy and Horticulture: Faculty Publications

Breeding hybrids with maximum heterosis requires efficient cross-pollination and an improved male sterility system. Renewed efforts have been made to dissect the phenotypic variation and genetic basis of hybrid floral traits, although the potential of tailoring the appropriate flower design on seed setting is less known. To this end, elite wheat genotypes were crossed using a chemical hybridizing agent at different doses. A total of 23 hybrids were developed from a partial diallel design; and planted in an alpha lattice design with their parents at two locations in Morocco, for two years, to evaluate for yield components, heterosis and combining …

Insecticide Resistance In Australian Spodoptera Frugiperda (J.E. Smith) And Development Of Testing Procedures For Resistance Surveillance, Lisa Bird, Melina M. Miles, Adam Quade, Helen Spafford

Biosecurity Research Articles

Spodoptera frugiperda (J.E. Smith) is a highly invasive noctuid pest first reported in northern Australia during early 2020. To document current status of resistance in S. frugiperda in Australia, insecticide toxicity was tested in field populations collected during the first year of establishment, between March 2020 and March 2021. Dose-response was measured by larval bioassay in 11 populations of S. frugiperda and a susceptible laboratory strain of Helicoverpa armigera. Emamectin benzoate was the most efficacious insecticide (LC50 0.023μg/ml) followed by chlorantraniliprole (LC50 0.055μg/ml), spinetoram (LC50 0.098μg/ml), spinosad (LC50 0.526μg/ml), and methoxyfenozide (1.413μg/ml). Indoxacarb was the least toxic …

Post-Termination Effects Of Cover Crop Monocultures And Mixtures On Soil Inorganic Nitrogen And Microbial Communities On Two Organic Farms In Illinois, Eleanor E. Lucadamo, Ashley A. Holmes, Samuel E. Wortman, Anthony C. Yannarell

Department of Agronomy and Horticulture: Faculty Publications

Cover crops can continue to affect agricultural systems even after they have been terminated by influencing nitrogen dynamics and by altering soil microbial communities. These post-termination effects can influence soil fertility, weed pressure, and the dynamics of potential plant pathogens in the narrow window of time between cover crop termination and cash crop emergence. We evaluated the post-termination effects of 12 different spring-sown cover crop mixtures and monocultures on soil nitrogen and microbial communities on two different organic farms in Central Illinois (on Lawson silt loam soil) and Northern Illinois (on Virgil silt loam soil). In comparison to control plots …

Post-Termination Effects Of Cover Crop Monocultures And Mixtures On Soil Inorganic Nitrogen And Microbial Communities On Two Organic Farms In Illinois, Eleanor E. Lucadamo, Ashley A. Holmes, Samuel E. Wortman, Anthony C. Yannarell

Department of Agronomy and Horticulture: Faculty Publications

Cover crops can continue to affect agricultural systems even after they have been terminated by influencing nitrogen dynamics and by altering soil microbial communities. These post-termination effects can influence soil fertility, weed pressure, and the dynamics of potential plant pathogens in the narrow window of time between cover crop termination and cash crop emergence. We evaluated the post-termination effects of 12 different spring-sown cover crop mixtures and monocultures on soil nitrogen and microbial communities on two different organic farms in Central Illinois (on Lawson silt loam soil) and Northern Illinois (on Virgil silt loam soil). In comparison to control plots …

Practice Cost And Size Differences In Invasive Plant Management Strategies: An Empirical Analysis Of Us Great Plains States, Mazbahul G. Ahamad

Department of Agronomy and Horticulture: Faculty Publications

Grassland conservation of the Conservation Stewardship Program in the United States (US) is one of the largest cost-sharing initiatives for protecting grazing land from invasive and woody plants. The practice cost and unit size of various invasive and woody plant management strategies, such as mulching, brush management, and pre- scribed burning, are different from state to state. We aimed to compare and examine the association between practice cost ($/acre[ac]) and standard unit size of practice (acre) of mulching, brush management, and pre- scribed burning strategies in nine US Great Plains states, including Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, …

Non-Escaping Frost Tolerant Qtl Linked Genetic Loci At Reproductive Stage In Six Wheat Dh Populations, Jingjuan Zhang, Md Shahidul Islam, Yun Zhao, Masood Anwar, Zaid Alhabbar, Maoyun She, Rongchang Yang, Angela Juhasz, Guixiang Tang, Jiansheng Cheng, Darshan L. Sharma, Nathan Height, Ben Biddulph, Hang Liu, Yanjie Jiang, Shengnan Zhai, Xin Hu, Junkang Rong, Yingquan Zhang, Yebo Qin, Qier Liu, Zitong Yu, Yujuan Zhang, Sadegh Balotf, Mirza Dowla, Sonia Afrin, Nandita Roy, Md Resad Mallik, Md Atik Us Saieed, Shanjida Rahman, Nigarin Sultana, Sarah Al-Sheikh Ahmed, Chris Florides, Kefei Chen, Meigin Lu, Jorge E. Mayer, Wujun Ma

Grain and Other Field Crops Research Articles

Reproductive stage frost poses a major constraint for wheat production in countries such as Australia. However, little progress has been made in identifying key genes to overcome the constraint. In the present study, a severe frost event hit two large-scale field trials consisting of six doubled haploid (DH) wheat populations at reproductive stage (young microspore stage) in Western Australia, leading to the identification of 30 robust frost QTL on 17 chromosomes. The major 18 QTL with the phenotype variation over 9.5% were located on 13 chromosomes including 2A, 2B, 2D, 3A, 4A, 4B, 4D, 5A, 5D, 6D, 7A, 7B and …

Arkansas Cotton Variety Test 2021, F. Bourland, A. Beach, B. Milano, C. Kennedy, L. Martin, B. Robertson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Test is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant. These annual evaluations will then facilitate the inclusion of new, improved genetic material in Arkansas cotton production. Adaptation of varieties is determined by evaluating the lines at five University of Arkansas System Division of Agriculture research sites (Manila, Keiser, Judd Hill, Marianna, and Rohwer). The 2021 tests at Rohwer were abandoned due …

Implementation Of Epigenetic Variation In Sorghum Selection And Implications For Crop Resilience Breeding, Dikungwa Ketumile, Xiaodong Yang, Robersy Sanchez, Hardik Kundariya, John F. Rajewski, Ismail M. Dweikat, Sally A. Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

Crop resilience and yield stability are complex traits essential for food security. Sorghum bicolor is an important grain crop that shows promise for its natural resilience to drought and potential for marginal land production. We have developed sorghum lines in the Tx430 genetic background suppressed for MSH1 expression as a means of inducing de novo epigenetic variation, and have used these materials to evaluate changes in plant growth vigor. Plant crossing and selection in two distinct environments revealed features of phenotypic plasticity derived from MSH1 manipulation. Introduction of an epigenetic variation to an isogenic sorghum population, in the absence of …

Assessment Of Bacterial Inoculant Delivery Methods For Cereal Crops, Yen Ning Chai, Stephanie Futrell, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Despite growing evidence that plant growth-promoting bacteria can be used to improve crop vigor, a comparison of the different methods of delivery to determine which is optimal has not been published. An optimal inoculation method ensures that the inoculant colonizes the host plant so that its potential for plant growth-promotion is fully evaluated. The objective of this study was to compare the efficacy of three seed coating methods, seedling priming, and soil drench for delivering three bacterial inoculants to the sorghum rhizosphere and root endosphere. The methods were compared across multiple time points under axenic conditions and colonization efficiency was …

Effects Of Foliar Application Of Zno Nanoparticles On Lentil Production, Stress Level And Nutritional Seed Quality Under Field Conditions, Marek Kolenčík, Dávid Ernst, Matej Komár, Martin Urík, Martin Šebesta, Ľuba Ďurišová, Marek Bujdoš, Ivan Černý, Juraj Chlpík, Martin Juriga, Ramakanth Illa, Yu Qian, Huan Feng, Gabriela Kratošová, Karla Čech Barabaszová, Ladislav Ducsay, Elena Aydın

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Nanotechnology offers new opportunities for the development of novel materials and strategies that improve technology and industry. This applies especially to agriculture, and our previous field studies have indicated that zinc oxide nanoparticles provide promising nano-fertilizer dispersion in sustainable agriculture. However, little is known about the precise ZnO-NP effects on legumes. Herein, 1 mg·L⁻¹ ZnO-NP spray was dispersed on lentil plants to establish the direct NP effects on lentil production, seed nutritional quality, and stress response under field conditions. Although ZnO-NP exposure positively affected yield, thousand-seed weight and the number of pods per plant, there was no statistically significant …

Seed-Shattering Phenology At Soybean Harvest Of Economically Important Weeds In Multiple Regions Of The United States. Part 3: Drivers Of Seed Shatter, Lauren M. Schwartz-Lazaro, Lovreet S. Shergill, Jeffrey A. Evans, Muthukumar V. Bagavathiannan, Shawn C. Beam, Mandy D. Bish, Jason A. Bond, Kevin W. Bradley, William S. Curran, Adam S. Davis, Wesley J. Everman, Michael L. Flessner, Steven C. Haring, Nicholas R. Jordan, Nicholas E. Korres, John L. Lindquist, Jason K. Norsworthy, Tameka L. Sanders, Larry E. Steckel, Mark J. Vangessel, Blake Young, Steven B. Mirsky

Department of Agronomy and Horticulture: Faculty Publications

Seed retention, and ultimately seed shatter, are extremely important for the efficacy of harvest weed seed control (HWSC) and are likely influenced by various agroecological and environmental factors. Field studies investigated seed-shattering phenology of 22 weed species across three soybean [Glycine max (L.) Merr.]-producing regions in the United States. We further evaluated the potential drivers of seed shatter in terms of weather conditions, growing degree days, and plant biomass. Based on the results, weather conditions had no consistent impact on weed seed shatter. However, there was a positive correlation between individual weed plant biomass and delayed weed seed-shattering rates during …

Corn Nitrogen Nutrition Index Prediction Improved By Integrating Genetic, Environmental, And Management Factors With Active Canopy Sensing Using Machine Learning, Dan Li, Yuxin Miao, Curtis J. Ransom, Gregory Mac Bean, Newell R. Kitchen, Fabián G. Fernández, John E. Sawyer, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Carrie A. M. Laboski, Emerson D. Nafziger, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Accurate nitrogen (N) diagnosis early in the growing season across diverse soil, weather, and management conditions is challenging. Strategies using multi-source data are hypothesized to perform significantly better than approaches using crop sensing information alone. The objective of this study was to evaluate, across diverse environments, the potential for integrating genetic (e.g., comparative relative maturity and growing degree units to key developmental growth stages), environmental (e.g., soil and weather), and management (e.g., seeding rate, irrigation, previous crop, and preplant N rate) information with active canopy sensor data for improved corn N nutrition index (NNI) prediction using machine learning methods. Thirteen …

Tracking Spatial Regimes In Animal Communities: Implications For Resilience-Based Management, Caleb P. Roberts, Daniel R. Uden, Craig R. Allen, David G. Angeler, Larkin A. Powell, Brady W. Allred, Matthew O. Jones, Jeremy D. Maestas, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

Spatial regimes (the spatial extents of ecological states) exhibit strong spatiotemporal order as they expand or contract in response to retreating or encroaching adjacent spatial regimes (e.g., woody plant invasion of grasslands) and human management (e.g., fire treatments). New methods enable tracking spatial regime boundaries via vegetation landcover data, and this approach is being used for strategic management across biomes. A clear advancement would be incorporating animal community data to track spatial regime boundaries alongside vegetation data. In a 41,170-hectare grassland experiencing woody plant encroachment, we test the utility of using animal community data to track spatial regimes via two …

Water Use Characteristics Of Weeds: A Global Review, Best Practices, And Future Directions, Mandeep Singh, Meetpal Singh Kukal, Suat Irmak, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds usually penalize crop yields by competing for resources, such as water, light, nutrients, and space. Most of the studies on the crop-weed competition domain are limited to assessing crop-yield losses due to weed pressure and other crop-weed interactions, overlooking the significant uptake of soil-water by weeds that exacerbates global water constraints and threatens the productivity and profitability. The objective of this review was to synthesize globally available quantitative data on weed water use (WU) sourced from 23 peer-reviewed publications (filtered from 233 publications via a multi-step protocol of inclusion criteria) with experimental investigations across space (3 continents), time (1927–2018), …

Management-Intensive Grazing Impacts On Total Escherichia Coli, E. Coli O157: H7, And Antibiotic Resistance Genes In A Riparian Stream, Laura M. Rubeck, James E. Wells, Kathy Hanford, Lisa M. Durso, Walter H. Schacht, Elaine D. Berry

Department of Agronomy and Horticulture: Faculty Publications

The impacts of management-intensive grazing (MIG) of cattle on concentrations of total Escherichia coli, total suspended solids (TSS), and nitrate-nitrite nitrogen (NO₃+NO₂-N), and occurrence of E. coli O157:H7 and selected antibiotic resistance genes (ARGs) in stream water and/or sediments were evaluated. Cattle were grazed for twoweek periods in May in each of three years. Overall, grazing increased total E. coli in downstream water by 0.89 log10 MPN/100 mL (p < 0.0001), and downstream total E. coli concentrations were higher than upstream over all sampling intervals. Downstream TSS levels also increased (p ≤ 0.0294) during grazing. In contrast, there was …