Research and Special Projects

Dr. Jane Pierce

Image of Jane Pierce with Cotton

Integrated Pest Management of Insects in New Mexico Cotton, Alfalfa and Pecan
Research Assistant: Patricia Yates Monk

Our program goal is to use research to adapt, develop or discover insect pest management tactics that are most useful for New Mexico conditions. Those conditions include our desert environment and agronomic practices or varieties used in New Mexico. Our research has addressed the use of multiple methods of control with projects focusing on host plant resistance, biological controls or cultural controls in cotton, alfalfa and pecan. Current research projects include: evaluating biological control of alfalfa weevil in New Mexico; determining the impact of management practices on crop microclimate and control of insect pests in cotton and pecan; cotton yield partitioning and compensation; and variation in insect resistance in Bt cotton varieties.

Jim Ross

Pesticide Application Technology

Currently we are constructing artificial pecan leaves that will enable us to quantify pesticide deposits on upper and lower leaf surfaces. We believe that we have solved the problems of last season and look forward to collecting data that will help determine the spray droplet size that increases deposit on the underside of leaves to control pecan aphids. We plan to fly some transects using the NASA GPS receiver to gather soil moisture data for Bob & staff at CARSAME.

Dr. David Thompson

Biological control of riparian and rangeland weeds using insects

  1. Biology of a native rangeland grasshopper, Hesperotettix viridis, that may be a biological control agent against broom snakeweed.
    • Economics of variable range management techniques to maintain grasshopper populations.
  2. Managing native insects to control broom snakeweed.
    • Artificially creating refugia. The original study set up in 2001 was lost due to the severe drought conditions during summer 2002 and 2003. I hope to find another site to reestablish a study using herbicides to create refugia and follow insect populations and associated plant growth.
    • Continue research on the influence of native insects on the species composition of snake weeds in the southwest.
  3. Biology and damage potential of native insects on purple and white locoweed.
    • Continue research on the influence that plant feeding by native biological agents has on swainsonine content of locoweed plants.
    • Drought in NE NM setback this research; however, I hope to evaluate the release of weevils collected in Colorado that feed on white locoweed in NE New Mexico. Collect and release more weevils during 2004
  4. Field release and monitoring of biocontrol agents for noxious weeds.
    • Evaluate biological control agents released on leafy spurge during in previous years.
    • Use GPS technology to delineate the extent of as many of the noxious weed populations in New Mexico as possible. Most effort will be on leafy spurge, spotted and diffuse knapweed, yellow starthistle, dalmatian toadflax and others as time permits.
    • Monitor and establish new releases of the salt cedar leaf beetle, Diorhabda elongata, on the Pecos River in eastern NM.
    • If USFWS approval is obtained, we will release and monitor salt cedar leaf beetles in the Rio Grande and/or Gila River drainages.
  5. Studies in high containment insect facility or Quarantine Lab
    • Phorid flies attacking Red Imported Fire Ant. If needed screen available Phorid flies for host specificity and help develop techniques to mass rear the flies.
    • Explore the potential of any new biological control agents of salt cedar as they become available.
    • Hybridization studies of the saltcedar leaf beetle, Diorhabda elongata, in the laboratory.
    • Host range testing of a stem boring Scolytidae, Thamnurgus pegani, a potential biological control agent for African rue.

Dr. Scott Bundy

Image of Dr. Scott Bundy

Alfalfa and Cotton Entomology

Summary: My research focus is to develop an Integrated Pest Management System for the arthropods of alfalfa and cotton in New Mexico. Primary research interests include the effects of alfalfa weevil strains on management strategies and economic injury levels, effects of established and potential methods of host plant resistance for insect management, and evaluation of other potential tools for pest management including arthropod biocontrol agents and assessments of insecticide efficacy. Secondary research interests include the ecology and taxonomy of the Heteroptera.

Current research projects include genetic analyses of alfalfa weevil strains, their distribution in the state, and implications for management; evaluation of the efficacy of okra-leaf cotton as a mechanism of host-plant resistance, and its microclimatic effects on pests and beneficials; a survey of the spiders of cotton in New Mexico and their potential impact on upland, pima, Bt, and organic cotton; pesticide bioassays for cowpea aphid in alfalfa and pink bollworm in cotton; and bionomics of Mecidea, with descriptions of immature stages.

Dr. Rebecca Creamer

Etiology and Management of Plant Diseases

The laboratory research focuses on two major areas of importance to New Mexico agriculture, plant viruses and a fungal endophyte of locoweed. We are currently characterizing the biology and epidemiology and Beet curly top virus which infects chile in New Mexico. This virus infects many crops and weed hosts throughout the western US. Research is ongoing to examine viral strain variation within fields and between fields at the molecular level, characterize new virus strains, study the biological and molecular differences in the leafhopper vector of the virus from different locations, and search for host resistance in pepper, as well as to document the role of weed hosts and vector populations in disease epidemiology.

We are also studying the role that a fungal endophyte of locoweed plays in the toxicity of this plant. We have begun the characterization of this fungus that produces a mannosidase inhibitor toxin, swainsonine, that is poisonous to grazing animals. We are looking at the genetics of the fungus, a new species of Embellisia, and trying to determine the genetic variability in fungal isolates from different locoweed species. We are seeking to find how environmental factors influence swainsonine production. We are studying the localization of the fungus in the plant and how it moves from the seed coat to germinating seedlings. We are trying to determine the pathway of toxin biosynthesis through biochemical and genetic means.

Dr. Jill Schroeder

Image of Dr. Jill Schroeder

Weed Science Related Programs

Personnel: Cheryl Fiore, Research Assistant

We have been conducting field and greenhouse research at the Leyendecker Plant Science Research Center since 1988. Research has included field evaluations of candidate herbicides for use in chile pepper, onion, cotton, grain sorghum, corn, and pecans; determination of the economic benefit of herbicides and cultivation for weed management in chile pepper; effect of weeds on yield and quality of chile pepper; and growth characteristics of some of the problem weeds found in southern New Mexico production systems. The research has defined the problems that weeds pose in production agriculture in New Mexico and has provided information concerning the effectiveness of herbicides in our soils and under our environmental conditions.

This research program has sponsored undergraduate and graduate student research projects each year. Many of the students conducting research projects in this program have had the opportunity to present the results of their work at a professional meeting. In addition, we maintain a weed garden for use by students taking the weed science classes at NMSU, other programs in the college, and the public.

Project One

This first, long standing collaborative effort has been working to understand the relationship between yellow and purple nutsedge (two perennial sedges that are among the world’s worst weeds) and root-knot nematodes (a plant parasitic nematode that is common world-wide). We work with Drs. Steve Thomas (EPPWS), Leigh Murray (Experimental Statistics, Kansas State University), and other scientists to understand the biological interactions between these two pest groups and to develop sustainable management strategies for fields infested with this pest complex. The research is unique and has determined that, unlike the crop plant, the weeds are either unaffected or grow better in the presence of the nematode. We have found that using alfalfa as a rotational crop with chile pepper may reduce populations of both pest groups enough to grow one season of chile without pesticide inputs. However, additional work is needed to further understand the biological interactions among these pests and to develop additional rotations to provide economically and environmentally sustainable options for fields infested with this pest complex.

Project Two

The second project is a new project evaluating the effect a newly discovered pest complex in chile pepper fields. This project is a collaborative effort with Drs. Soum Sanogo and Steve Thomas. We identified a chile field in 2007 where chile and three annual weeds, spurred anoda, Wright groundcherry and tall morningglory, were all infested with both Verticillium dahliae and root-knot nematode. Research is in progress to learn more about the effects of the parasite and pathogen on these plant species with the ultimate goal being to develop better management of this newly identified pest complex.

Project Three

The third project involving biological interactions is a new project in collaboration with Drs. Rebecca Creamer (EPPWS), Scott Bundy, and Leigh Murray. The project will model the three way interaction between the winter annual weed, London rocket, beet leafhopper, and beet curly top virus that affects chile pepper. We measured the survival, growth and development of London rocket that germinates after fall rains and are currently studying the phonological development of the leafhopper on summer and winter weed hosts. The research will provide a predictive model for occurrence of the viral pest. In addition, we hope to learn more about how habitat affects presence of the leafhopper and virus on the plant community. This is important because growers currently have no management tools for virus problems in chile pepper.

Rio Grande Basin Initiative

The goal of this project is to manage vegetation growing along irrigation canals and in surrounding fields more effectively and sustainable, saving water and maintaining environmental quality. This is a cooperative project with Drs. April Ulery (Plant and Environmental Science.), Jamshid Ashigh (Extension Plant Sciences) and Leigh Murray (Experimental Statistics, Kansas State University). We have been working to identify and map the weeds along the irrigation canals using GIS. The goal of the project is to produce a data base of plants and soils along the irrigation canals of southern New Mexico. Statistical modeling shows that canal size (characterized by water flow and continuous versus intermittent flow) and soil texture influences presence of plant species including bermudaggrass and horsetail. Greenhouse research is being conducted to determine the relative water use by predominant plants on the irrigation canals and by several invasive plant species. This data has never been documented for the irrigation delivery system and will provide important baseline information to help us define the problems we are dealing with regarding water quality and water and vegetation management on the canals. The information will be helpful for researchers, EBID, water management programs, and the users (both rural and urban users). The information can be used to develop vegetation management strategies that target weeds that use high amounts of water or impede water flow in canals.

Dr. Jennifer Randall

Image of Dr. Jennifer Randall

The Randall Lab is focused on the genetic and molecular mechanisms of plant development and plant microbe interactions. We work with several pathogens that include bacteria, oomycetes, and fungal species that infect plants. We also study the innate plant ‘immune’ system and how to activate the immune system to help protect plants from pathogen invasion.

Dr. Steve Hanson

Molecular Biology and Biological Control of Soil-borne Fungal Diseases

My group's research is divided between two main areas, molecular biology / biotechnology and biological control of soil borne fungal diseases. Research in both areas focuses on understanding the basic biological processes involved in order to develop useful control measures that will increase the productivity of New Mexico agriculture.

Our molecular biology / biotechnology work is primarily aimed at diseases caused by viruses. Top among these is Beet Curly Top Virus (BCTV) which is one of the biggest current problems for New Mexico Chile producers today. BCTV is part of the geminivirus family, a group of viruses that cause severe damage on a number of crops throughout the world. Since there are no known sources of natural resistance for BCTV (or most other geminiviruses), my group's work is aimed at creating genetically engineered resistance to BCTV. To achieve this goal, we are currently doing a lot of basic molecular biology research to understand the fine details of how BCTV replicates at the molecular level. Other supporting work in the lab includes development of next generation molecular detection reagents and development of molecular techniques for the analysis of gene function in plants. The BCTV problem faced by Chile growers in New Mexico is a microcosm of agriculture across the world. Other geminiviruses are major constraints on the production of many crops throughout the world. Many of the worst problems are in third world countries where these viruses take a toll on subsistence level producers- people who need successful crops in order to feed their families. Ultimately, I hope that my groups work on controlling BCTV and other geminiviruses can contribute to improving the production of Chile here in New Mexico and a number of crops throughout the world.

Soil borne fungal diseases are another severe problem faced by New Mexico producers. Among these, Phytophthora capsici is a major cause of losses to New Mexico chile growers. The use of antagonistic bacterial to control diseases caused by several Phytophthora species and other fungi has been widely explored by many researchers for decades with variable success. Bacillus cereus is one bacterium that has proven effective for controlling Phytophthora caused diseased in other crops. In these other systems, the B. cereus harmlessly colonizes the plant root systems and prevents infection by fungi without harming the plant. My group is currently trying to develop B. cereus stains useful for protecting Chile from Phytophthora capsici. This work primarily involves identifying or creating new strains that are able to efficiently colonize the Chile root systems. We currently have several strains that work well under laboratory conditions. Future work on this project will involve continued optimization of strains in the lab and field testing of strains developed to date. Eventually, I hope to develop an effective biocontrol agent that can contribute to controlling soil borne diseases affecting New Mexico producers.

Dr. Steve Thomas

Plant-parasitic Nematodes Affecting New Mexico Agriculture

Additional researchers: Jacqueline Trojan, Research Specialist

General Overview:

Plant-parasitic nematodes are among the most serious pathogens of New Mexico crops. The most economically damaging nematode in the state is the southern root-knot nematode, Meloidogyne incognita. It is widely distributed and, without proper management, results in yield losses exceeding 40% in chile and 25% in cotton and most other crops. Other root-knot nematodes, including M. chitwoodi, M. partityla, and M. hapla, are much less widely distributed but pose serious threats to potato, pecan, and peanut, respectively. In addition to crop damage, the presence of some of these nematodes results in regulatory restrictions on the shipment of NM produce. Historically nematodes have been managed with pesticides, but the availability of such materials to NM producers has dwindled by 80% in recent years due to environmental concerns. As the expense of pesticide-based management has increased, so has the level of nematode damage to many crops. This program is broad in scope and endeavors to: determine how plant-parasitic nematodes interact with other pests and develop new sustainable management alternatives to pest complexes; enhance the efficacy of existing management options; educate the agricultural community regarding ways to avoid introducing new nematode pathogens; and develop protocols for identifying and managing new pest introductions. Most of our research is interdisciplinary and collaborative. Some current research projects are described below:

Image of Southern Root Knot Nematode

Nematode/weed/crop interactions:

As obligate parasites, root-knot nematodes must establish permanent feeding sites inside the roots of susceptible hosts in order to survive. This ongoing multidisciplinary project investigates the interactions among M. incognita, yellow and purple nutsedges (common perennial weeds that are alternative hosts for this nematode in NM), and locally important crops like chile, cotton and alfalfa. What we find intriguing about this association is that the pests appear to have developed mutually beneficial relationships favoring their survival in the presence of certain crops. Nutsedge tubers protect root-knot nematodes from pesticides and the environment, and emerging nutsedge plants serve as alternative food sources for the nematode. Unlike the nematode injury seen in crop plants, however, nutsedges are not damaged by nematode parasitism under agricultural conditions, but instead show increases in tuber production and tuber size, which enhances weed populations and survival in many annual cropping systems. In contrast, dense-canopied perennial crops like alfalfa, certain varieties of which possess resistance to root-knot nematodes, show promising results for use as a rotation crop to suppress this pest complex. The overall goal of this project is to develop effective, acceptable management practices that address the pest complex as a whole, since attempts to manage individual pest components have proven ineffective due to the interconnected beneficial relationships among the pests.

Pecan root-knot nematode:

A unique species of root-knot nematode, Meloidogyne partityla, which appears to only affect plants in the walnut family (pecan, walnut, and hickory), was discovered in 1996 from five pecan orchards around Texas. Shortly thereafter, we identified this nematode from mature trees in a diseased pecan orchard in New Mexico. Due to the difficulty in positively differentiating this root-knot species from other root-knot nematodes, we adapted an existing mt-DNA procedure for this purpose. Since then, we have confirmed the presence of M. partityla infested orchards in Arizona, Oklahoma, and additional locations in Texas. We have also monitored the seasonal population dynamics of this nematode on pecan for several years, and in so doing established the periods of peak nematode reproduction. There are no pesticide alternatives for management of M. partityla in pecan. Our goals with this project are to: examine the susceptibility of pecan and other perennial crops to M. partityla and other root-knot nematodes found in the state; determine the extent of pecan root-knot nematode infestation throughout NM orchards; assist in the curtailment of further dissemination of the pest; determine the potential for reducing pest severity through modification of cultural management practices. Collaborators: Mr. Brad Lewis, Entomologist.

Root-knot nematode host suitability of ornamental Southwestern plants:

Molecular identification and characterization of soil-inhabiting nematodes:

Dr. Soumaila Sanogo

Soilborne Fungal Plant Pathology/Aerobiology

Research Interests:

My research on soilborne diseases includes the following components: 1) etiology and ecology/epidemiology of soilborne pathogens; 2) soil amendments with biorational products, green manures, and crop residues for disease control; 3) disease resistance and pathogen race characterization; 4) pathogen nutrition and physiology; and 5) pathogenic interactions. The scope of my research spans a wide array of diseases including Phytophthora blight, Verticillium wilt, seedling diseases, stem rot and stem blight, anthracnose, bacterial leaf spot, bacterial wilt, fruit and pod rot, and root rot.

In addition to the work on soilborne pathogens, I am also conducting research in aerobiology, with emphasis on fungal microorganisms in dust particulate matters and rainwater. This a collaborative research aimed at assessing the quality of air in the borderland with Mexico, with collaborators from New Mexico State University and Mexico. Expected impacts in this area are the development of air quality indicators and identification of remedial measures for improving environmental quality.