Funded Projects

The updated and expanded economic contribution analysis of Yuma agriculture holds significant importance in understanding the multifaceted impact of agriculture activities on the local and regional economy. Through the Economic Base Analysis, Water Productivity Analysis, and Economic Contribution Analysis, researchers aim to provide a comprehensive overview of the economic significance of Yuma agriculture This study will not only contribute to academic research but also offer valuable insights for policymakers, stakeholders, and industry participants in fostering sustainable agricultural development and economic growth in the Yuma area.

In recent years the demand for organic cotton in the United States has surged, necessitating significant imports to meet domestic needs. Addressing this demand domestically not only alleviates dependence n costly imports but also promotes the local agricultural economies. Yuma, Arizona could be a promising location for organic cotton production due to the amount of available organic acres, water, and favorable growing climate for the crop. Considering organic cotton is a potentially profitable summer crop alternative, stakeholders in Yuma express interest in its cultivation, recognizing the potential to stimulate  economic growth. With limited chemical tactics in the organic toolbox, managing insect pests poses a challenge in all organic production. This research will evaluate selected bioinsecticides' efficacy against whiteflies and lygus bugs, which are the two most economically concerning pests in cotton production. Objectives include assessing bioinsecticide effectiveness, identifying alternatives for insecticide rotation, and interpreting natural enemies of pests in organic cotton. Field experiments will be conducted at the Yuma Agricultural Center Mesa farm in the summer of 2024 to gather data crucial for advancing organic cotton production in Yuma. Some of the objectives for this project include: 1. Evaluate the efficacy of selected bioinsecticides against whiteflies in organic cotton. 2. Evaluate the efficacy of selected bioinsecticides against the lygus bug in organic cotton. 3. Determine bioinsecticides  that can serve as alternatives for insecticide rotation when controlling whiteflies and lygus bugs. 4. Identify whiteflies and lygus bug natural enemies in organic cotton in Yuma. 

Fusarium wilt of lettuce, caused mainly by Fusarium oxysporum f. sp. lactucae, is one of the main biological threats to lettuce production in the Southwestern United States. there are currently few effective methods to prevent or treat infection by this fungal phytopathogen. One potential avenue for the development of new treatments is the isolation of microbes that re antagonistic against Fusarium oxysporum f. sp. lactucae, and specifically isolation of these microbes from the very fields and environments that can be severely affected by this pathogen in Yuma. We propose to carry out numerous isolations of bacterial strains from multiple fields over the course of the year, and to screen these isolates for potential antagonism against Fusarium oxysporum f. sp. lactucae. If we are able to isolate strains with antifungal activities of interest, future research will be carried out to further develop these strains for more widespread deployment as a preventative measure against Fusarium wilt in the field. 

Durum wheat is an important crop for Arizona agriculture, but its cultivation relies on abundant irrigation and nitrogen fertilizer. Future climatic scenarios require a shift to agricultural systems based on lower inputs which are likely to impact on yield and quality of crops. This study is designed to assess the impact of reduced quantities of water and nitrogen on grain yield and quality of durum wheat varieties that are currently available to the farmers. Plant metabolism is regarded as a functional intermediate of the plant physiological status and metabolite analysis is used in stress physiology to shed light on mechanisms of tolerance. In this study, low input-induced metabolic changes in the durum wheat varieties will be determined and their relationship with grain yield and quality performance will be analyzed. These relationships will help to inform new public and private research efforts aimed at maintaining grain yield and quality of durum wheat grown under a low input cultivation scenario that will need to be adopted in the near future in the US southwest desert farming areas.

Impatiens Necrotic Spot Virus (INSV) is a thrips transmitted virus that threatens the productivity of the Arizona lettuce industry. INSV was first found in Arizona in March 2021, since then the University of Arizona Cooperative Extension has collaborated on industry sponsored projects surveying weeds as INSV hosts across commercial lettuce fields. This project will continue such surveys and collect important data over summer 2022 that will help lettuce growers make INSV management decisions. We will continue and expand weed surveys in and around commercial fields during summer and leading into the produce season. This project is important to understand the role of weeds as secondary hosts of INSV, helping the virus persist during the non-lettuce season, and to identify the most critical hosts of INSV. Results will be widely disseminated to the Arizona lettuce industry to aid in INSV management decisions.

Assessing soil health status is essential for modern agricultural production systems. As soil gets exhausted due to intensive farming, measures should be taken to sustain soil health and productivity. Under extreme climates, soil processes behave differently that makes it ‘tricky’ to evaluate soil health, therefore, effective soil health assessment is necessary to design plans that improve and maintain soil health. Our study is designed to survey soils in the Yuma region, a low desert ecosystem in southwestern United States, to measure soil health indicators, documenting current soil health status. We will collect soils twice before cash crop season in the winter, preferably in the summer and in the fall season, from 20 farm sites; ‘historically’ good and bad sites will be included in this survey. A comprehensive suite of soil physical, chemical, and biological properties will be measured to evaluate soil health; standardized protocols will be used, and performance of different soil health indicators will be recorded. All soil health information will be shared with the participating growers and will be used for soil health outreach and education. Additionally, this project will serve as a ‘pilot study’ to draft future research proposals to assess soil health and devise better soil health management practices in Yuma. Through this project, the research team will build strong communication with the Yuma growers and YCEDA to identify major soil health needs in the region and will participate in the mission to improve soil health and productivity through sustainable intensification.

 https://extension.arizona.edu/pubs/yuma-soil-health-survey-2022-discussion-pox-c-pmn-soil-protein

Automated/robotic weeding machines are commercially available; however, their adoption has been limited because the machines 1) provide only partial weed control and follow up hand weeding is necessary, 2) have slow travel speed which results in low work rates and high operating costs and 3) lack precision and cannot remove doubles in lettuce crops. To overcome these limitations, we propose to develop an innovative high-speed, high-precision automated weeding machine. The machine will utilize an artificial intelligence (AI) based imaging system to identify weeds and a precision sprayer to spot spray targeted weeds at the 1-cm level of resolution. The 1-cm resolution spot sprayer has already been developed and successfully tested in a laboratory setting. The primary focus of the proposed project is to develop the AI-based imaging system. An additional goal is to integrate the imaging system with the precision spot sprayer and evaluate the system in the field. With promising preliminary data, we plan to seek funding to fully develop and prototype a high-precision automated weeding machine.
 

Data-driven agriculture promises to transform agriculture, but reliable and affordable data transfer from the field remains a bottleneck. Emerging sensing technologies including drone images can help monitor and inform crop as well as rangeland management. However, data collected in the field must be combined, analyzed, and returned to stakeholders as actionable information. To leverage new data streams, it is often necessary to move large data from the field to the cloud for automated analysis generation of reports with actionable information.

We plan to evaluate a new satellite communications technology that will be launched in 2021. The NSLComm satellite will transfer data from remote fields to the cloud for automated analysis and reporting. The NSLComm satellite uses a portable, low power transmitter the size and with a target cost of under one thousand dollars and transfer rate of one gigabit per second. By contrast, existing communications satellites require a large dish costing millions of dollars to transfer data at this rate.

We will develop and evaluate a data transfer and reporting pipeline that will highlight the new capabilities that this new satellite communications capability will enable. We will demonstrate a use case that will be of broad use to the industry: collecting aerial imagery in the field and automating the analysis and generation of crop status reports within twelve hours. This will reduce time to results and labor, and enable more timely decision support. This will be a first step toward high bandwidth data infrastructure for Arizona’s agriculture industry.

Soilborne plant pathogens live a double life. On one hand, they invade and colonize plant hosts, causing diseases. On the other hand, they are part of the soil “microbiome”, the complex community of all micro-organisms inhabiting the soil. 

In the last years, the role of the soil microbiome has been recognized as an important factor to consider for the development of efficient soil-borne plant pathogen control methods. The latest data shows how the occurrence of certain diseases can be triggered and/or influenced by soils’ biotic component. The complex ecological interactions occurring within soil microbial communities can provide a protective (or suppressive) effect on pathogens. A proper understanding and management of the soil microbiome is emerging as a necessity for developing control strategies. With this project, we aim at investigating the relationship between the occurrence of Fusarium wilt of lettuce (Fol) and the microbial communities inhabiting the soil in the cultivated fields of Yuma county, and how this relationship modulates plant disease. We will collect soil samples from both infected and non-infected soils associated to different farming practices, and we will quantify diversity and composition changes associated with disease. 

The outcomes of the project will be: (A) development of a methodology for the assessment of F. oxysporum lactucae; (B) describing the differences in microbial communities between healthy and diseased soils according to different agricultural practices, and (C) fundamental knowledge for a larger project investigating the soil abiotic and biotic properties of soils in Yuma with a specific focus on functional soil attributes and Fol disease occurrence.

Proper soil health is vital for productive agriculture. When soil health is ignored we quickly see salt build up, carbon depletion, mycorrhizal imbalances, erosion, and pH imbalances, which in turn reduces yield and quality of agricultural crops. There are many good cultural practices that have been developed to increase soil health, and products have been developed by industry to benefit the soil. However, the definition of soil health improvement is not universally agreed upon and is difficult to quantify. There is a desire in the grower community for the neutral third party testing of soil health amendments. Many of the soil health products available to purchase are not thoroughly tested on different crops grown in Yuma, using proper research trials, before being sold to growers. It is the purpose of this study to evaluate commercially available soil health products and their effects on Yuma agriculture. Funding will be used to purchase tools and supplies to conduct ongoing and future experiments designed to validate soil health product label claims and determine how they best fit into Yuma agricultural practices. All results from the research trials will be disseminated to Yuma growers, PCAs, and CCAs through extension bulletins and newsletters.

Soil health is the essential capacity of a soil to function as a living ecosystem that sustains plants, animals, and humans. Soil health conservation is a top research priority identified by Yuma growers, but they currently lack data for best management practices to improve soil health. One potential beneficial practice is planting cover crops during the spring and summer fallow period when vegetables can’t be grown, instead of leaving soils bare. Cover crops have been shown to improve physical, chemical, and biological components of soil health in wetter climates, but there’s no evidence from hot, hyper-arid regions like Yuma. Improving soil health may also help fend off Fusarium wilt. Therefore, this project will address two urgent questions: (1) Does cover cropping improve Yuma soil health? (2) Which currently used cover crop improves soil health more—cotton or Sudan grass? In a field with the same winter vegetable and soil type, the research team will quantify benefits of cotton and Sudan grass compared to fallow areas using a suite of soil health metrics. Soils will be evaluated in July 2020 after cover crops are incorporated but before beds are prepared for vegetables. Project outcomes will be: (1) a methodology for Yuma soil health assessment, (2) a scientific publication advancing knowledge of cover crop effects on desert soil health, and (3) preliminary results to increase the competitiveness of multiple $500k+ grant proposals for future studies of novel cover crops, long-term trends, and additional management practices to conserve and enhance soil health in desert agriculture.

A publication from Cornell University documented that industrial hemp can be grown as a baby leaf salad green. High density plantings were made in a green house and plants at three leaf stage were harvested in as little as three weeks. Since Yuma County produces 90% of the domestically consumed leafy greens during the winter months, ways to promote increased vegetable consumption is economically important to our region. One way to increase consumption is to introduce new varieties that are appealing to consumers. This study will evaluate the potential for growing baby leaf hemp in Yuma County. A baby leaf hemp variety trial will be harvested and a consumer sensory evaluation completed.

Salmonella enterica, Escherichia coli O157:H7 and Listeria monocytogenes are pathogens frequently involved in foodborne outbreaks and have been isolated from irrigation water. For conventional pathogen detection, cultural methods such as enrichment and plating followed by confirmation are used to detect foodborne pathogens, and this method often takes 1-2 days, rendering the work long and cumbersome. A biosensor was developed by Phoenix Biometrics to detect airborne bacteria, viruses, and spores as well. The sensor is compact, light-weight, portable and provides “real-time” detection and characterization. The objective of this study is to evaluate the efficacy of the biosensor in detecting foodborne pathogens in water, by comparing the results between the biosensor and the plating method.

Lettuce (Lactuca sativa L.) production in Arizona is one of the most valuable agricultural industries within the state as demonstrated by the fact that Arizona provides over 90% of the nation’s winter leafy greens. However, like all agricultural production, it is threatened by both abiotic and biotic stresses that can cause significant economic losses for growers as well as the local economies that lettuce production supports. To combat these challenges, having fast, quantitative methods to assess the overall health and status of lettuce plants in the field is imperative, and methods that are developed must provide actionable information to growers and be of scientific value to researchers. This research proposal seeks to leverage recent advancements in unmanned aerial vehicle (UAV)-based thermography to test and evaluate its use in lettuce production for two specific objectives: i) detecting and quantifying water deficit stress for use in basic science research; ii) and identifying the presence of Fusarium wilt in grower fields for production applications. The results of this research will assist plant breeders and geneticist in the task of developing more stress resilient cultivars via understanding the genetic mechanisms of stress adaptive traits that can be bred for while producers will benefit through the development of a high-throughput method to identify and map the location of Fusarium infected plants in their field. Through the early detection of plant stress in the field, lettuce producers will be better equipped to make timely management decisions in-season to conserve or reallocate crop resources to maximize profitability.

The rapidly increasing spatial and temporal resolution of optical satellite observations and significant improvements and cost reductions of drone platforms and associated land surface imaging hardware make remote sensing (RS) techniques highly viable for farm-level, near real-time estimation of soil moisture and crop water consumption (i.e., evapotranspiration). This information can be used as decision support by Yuma producers and irrigation districts for accurate water allotment planning and irrigation scheduling, or help farmers in Central Arizona with water conservation, which is vital in view of looming Central Arizona Project (CAP) water reductions. It will be possible to establish water budgets for large farms and determine water productivity, water use efficiency, irrigation efficiency, and crop water availability considering the varying soil properties.

The University of Arizona is seeking an in-kind match of $10,000 towards the goals and objectives of a Center for Produce Safety proposal entitled, Agricultural Water Treatment – Southwest Region. The overall goal of this project is to evaluate three irrigation water treatment options available to industry to successfully achieve reductions in generic E.coli and Total Coliform bacteria, in response to recent LGMA water treatment metrics and to aid in improved public health protection.