Completed Research Projects
The agricultural community needs to improve nutrient use efficiency for modern cropping systems to ensure agronomic viability and environmental quality. This will require a different approach to nutrient management: the use of adaptive management concepts and processes. This project will develop technical and educational tools to encourage adaptive management.
The expansive growth of solar photovoltaics (PV) in Massachusetts has helped make the state a leader in renewable energy production, but there have been public concerns regarding the development of agricultural lands for solar PV electricity production. In response to these concerns, the Massachusetts Department of Energy Resources (DOER) included provisions in the new state solar energy program which limit conventional ground-mounted solar arrays on farmland, while encouraging innovative "dual-use" technology. Under the new Solar Massachusetts Renewable Target (SMART) program, there is a significant financial incentive for dual-use systems which limit shading and obstructions, and require continued agricultural production on the land below and around solar arrays.
People depend on vegetables to provide major portions of the nutrition for healthy diets. For several years, the mineral nutrient elemental concentrations in vegetables has declined. The decline has been associated with the development of new cultivars of vegetables that have lower concentrations of nutrients than heirloom cultivars. Breeding of crops for accumulation of nutrients has potential for developing nutrient-rich vegetables but has not received much attention in genetic improvement of vegetables. Cultural practices may give great and practical process for enhancing nutrient concentrations in vegetables, and cultural practices concerning fertilization to enhance nutrients in vegetables will be a priority in this project. Organic fertilization of crops is required for certification of organic produce. Producing equal yields and equal nutrient contents in organically fertilized vegetables compared to vegetables fertilized with chemicals are challenges. The research in this project will evaluate cultural methods that may be employed to enrich nutrient contents in vegetables through practices of fertilization organically or conventionally.This project includes a series of related experiments to assess nutrient accumulation in vegetables, primarily lettuce, in response to selection of cultivars of crops and management of fertilization. Organic fertilization will be compared to conventional practices of fertilization to determine growth and composition of lettuce in field plot and greenhouse investigations. Investigations concerning hydroponic production and modification of soil-based or peat-based media with organic or microbial amendents will be conducted to assess the effects of these amendments on productivity and nutrient composition of produce from vegetables.
Nanoparticles (NPs) are defined as particles with at least one dimension smaller than 100 nm. As particle size decreases the reactivity of the surface atoms could increase dramatically. These unique properties make nano-sized particles valuable engineering materials because of their extraordinary strength, chemical reactivity, electrical conductivity, or other characteristics that the same material does not possess at the micro- or macro-scales. ENPs are being exposed to different environmental niches via deposition of airborne NPs, application of agrochemicals containing NPs, accidental spills, land application of sewage sludge biosolids, and landfill leachates. There the environmental risks of ENPs are attracting increasing attention from both the public and scientific communities due to their toxicity to organisms. The main pathways through which MNPs are introduced to arable soils are the application of sewage sludge (biosolids) and irrigation with treated wastewater. These agricultural practices are common in many countries including USA. Contamination of agricultural soils with ENPs is of great concern due to their uptake by crops, thus posing the problem to food safety and exposure to humans. To ensure safe application of biosolids and irrigation with treated wastewater containing ENPs, there is an urgent need to investigate the fate of ENPs in the soil-water-planMass Agricultural Experiment Stationt system and to evaluate the associated risks. Therefore, this research will determine the environmental fate and process of several types of ENPs and their plant uptake and translocation in soil-water-plant systems. Also, we will study how ENPs affect the availability and uptake of other contaminants (e.g., metals and antibiotics) by plants. The results of this study are expected to help us understand how these ENPs interact with soil and water reactive components (e.g., DOM, clays). In addition, we will better understand the retention, bioavailability, uptake and translocation, transformation and phytotoxicity of ENPs in soil-waterplant system. Also, we can provide useful data for assessing the mobility, exposure and risk of ENPs in agriculture and the environment in general.
This research continues exploration of biological (non pesticide) control of a series of invasive plant and insect species that affect crops and forests.
African trypanosomes are flagellated protozoa that cause sleeping sickness in people and Nagana in domestic animals. These diseases are fatal if left untreated. The diseases are endemic in the humid and semi-humid zones of Africa affecting a landmass of 10 million km 2 and 36 countries. Trypanosomiasis precludes cattle-based agriculture from much of this area and threatens up to 60 million people, of whom about a half million are presently infected.
It is known that legumes generally respond to existing N in the soil. When soil N is relatively high, legumes prefer to use soil N rather than to engage in symbiosis with rhizobia. However, the ecophysiological responses of legumes to existing soil-N level and the changing climate - including temperature changes and precipitation dynamics impact rhizobia nodulation - have not been studied in actual field conditions. This study seeks to understand these responses in order to improve N management, maximize the benefits of legumes, reduce off-farm inputs, and enhance soil health. Moreover, growth and N accumulation of legumes is heavily dependent upon the nitrogen-fixing performance of the microbial partner recruited by the host legume. Native rhizobia strains in the Northeast that associate with faba bean (Vicia faba) and sunn hemp (Crotalaria juncea), two multi- purpose legumes newly introduced by the current project team to the area, have not been identified. In this project, native strains will be recovered from nodules, genetically sequenced, and their performance will be compared with elite strains maintained at USDA.
This research will examine possible affects of climate change on certain agricultural crop plants. It will include experiments that will allow prediction of how timothy and alfalfa plants will respond to future elevated CO2 and O3 levels.
This research involves modeling of cell growth, metabolite production rates, and product yields on various feedstocks using a variety of target organisms that can perform the bioprocess. These emphases need to be addressed prior to commercial implementation of generation of biofuels and industrial precursors from hydrothermal vent microbes.
The market for specialty foods targeted for Latino populations is especially strong in New England. While most of these foods are imported, many can be locally grown, offering a strong and increasing market for local farmers. We will work to evaluate germplasm of Latin American specialty crops with the objective of identifying parental materials to initiate a breeding program for these crops.
This project focuses on male equine infertility from several perspectives: 1) understanding at the molecular level the mechanisms of the causes of male infertility; 2) Methods to be developed during this project could easily be translated to standardized tests in the clinical laboratory; 3) Understanding of male infertility at the molecular level could provide rational strategies to treat infertile stallions and/or improve assisted reproductive technology.
This project will develop and diversify Crambe (an oilseed crop) and brassica (mustard green) species as dedicated bioenergy crops for biodiesel production. The proposed strategy will increase crop biomass and seed yields while growing these crops on marginal and heavy-metal-contaminated lands, thus increasing both yield and arable acreage.
This effort will develop local production and post-harvest practices to assist Massachusetts farmers to produce high quality Chinese medicinal plants with uniform levels of bioactive constituents. This will ensure the type of plant material desired by practitioners of acupuncture and Oriental medicine. This will benefit growers, practitioners, and those in need of healthcare. The establishment of Chinese medicinal herbs in Massachusetts could provide an income source for small farms and help maintain rural farmland.
This project will explore the hypothesis that development of an effective LAMP assay (loop-mediated isothermal amplification) for livestock and avian chlamydiosis will lead to significant reductions in zoonotic disease as well as morbidity, mortality and the reproductive health of farm animals.
The goals of this project are to supply apple growers with new tools that will enable them to continue towards a goal of sustainability while providing local consumers with a safe and healthful supply of fruit. As such, it will research new methods, educate growers, and engage consumers and wholesalers in Integrated Pest Management.
In this project, we will focus on key pest and water management practices for large-fruited, high-yielding cranberry hybrid cultivars. Cranberry fruitworm (CFW) is the most damaging pest insect in MA cranberry and presents a significant hurdle to maximizing yield. An understanding of pest-host dynamics is the key to managing this pest but has yet to be developed for new high-yielding cultivars, especially those most recently introduced. Weed management is critical to long-term sustainability and profitability for cranberry growers since weeds primarily compete with cranberry vines for water, nutrients, and space (Patten and Wang 1994). Herbicides are an important and critical tool needed to ensure proper colonization and vine health during establishment and for the life of the bed. However, we have very little information on the susceptibility of new hybrid cultivars to currently registered herbicides. Fruit rot, a complex disease caused by at least 15 different fungal species, is responsible for a majority of grower losses ascribed to 'poor quality' and is often especially a problem on young beds. In recent years, chlorothalonil fungicide has been the backbone of management for this disease but changes in the European Union have eliminated its use on fruit destined for that market. Most of the alternative materials have specific modes of action that present a higher risk of developing fungicide resistant pathogen populations. A potential contributing factor to poor fruit quality (rot and lack of firmness) is irrigation management both in regards to soil moisture and in its use for cooling the plants. The 2012 Farm Bill identified specialty crop production and research as priorities. This entire project addresses challenges to the production of a specialty fruit crop. USDA priorities for specialty crops research include threats from pests and diseases. Climate change and water are priorities for NIFA programs. In addition, the research proposed is aligned with grower-identified priorities (Cape Cod Cranberry Growers Association, Cranberry Institute).
The primary beneficiaries of this research will be Massachusetts cranberry growers and the handlers who receive the fruit. Growers and handlers in other cranberry regions of the U. S. (Wisconsin, New Jersey, Pacific Northwest) will benefit to the extent that much of the knowledge gained in this project will be transferable to those regions.
Threats to the sustainability of cranberry production in MA and elsewhere in the U.S. come from many sources: consumer demands for sustainable but inexpensive products, commodity pricing in an industry that is currently over-supplied with juice concentrate, changes to industry fruit quality standards, rising costs for energy and pest management products, and changing standards in pesticide use to accommodate global marketing.
Despite the fact that plants are a rich source of novel molecules, valuable to both basic and applied sciences, only a fraction of the pathways and compounds in plants have been explored. The project proposed here seeks to discover novel plant-produced natural products with unique and valuable properties, as well as the genes and pathways involved in their synthesis. At the core of this effort is an extensive living Plant Cell Culture Library (PCCL) that was recently (2014) donated to UMass by Monsanto.
This project proposes to capture DNA sequences from armored scale insects intercepted at plant quarantine stations, while carefully identifying each specimen in the traditional way by mounting on a microscope slide. The results -- DNA sequences from well-identified specimens—will help us develop a DNA-based system of identification, and also contribute to improving our understanding of the history and diversity of armored scale insects and their relationships with their host plants.
This project will examine methods to control undesirable sprouting in potatoes through breeding, transgenic strategies, or environmentally friendly agents.
This study is expected to reveal differences in one or more aspects of immune components and will aid in the understanding of how chronic exposure to certain organic pesticides may alter immune responses.
This projects involves two aspects of equine operations: manure handling and a comparison of footing materials. This project will evaluate two simple low cost aerated static composting systems for typical small acreage horse and/or livestock operations. In addition, it will evaluate various footing materials and provide the cost of operation and materials for each used material.
Current knowledge of the molecular mechanisms governing plant iron uptake and translocation is limited, as is our knowledge of how these processes are controlled at the molecular level. During this project, we will use molecular, biochemical, and physiological approaches to better understand mechanisms of nutrient (i.e., iron) uptake, a stated goal of the National Institute for Food and Agriculture (NIFA). The focus of this proposal is on gene discovery, an engine for crop improvement in two important ways. Most obviously, understanding of the molecular mechanisms responsible for iron uptake and homeostasis is a requirement for genetic engineering approaches to crop improvement. Without knowledge of the genes involved, we cannot know what engineered approaches could be taken. However, public acceptance of engineering approaches is limited, and partly because of this, breeding approaches have been extremely important in currently used efforts to enhance the iron concentration in the edible parts of plants. Many studies have identified quantitative trait loci (QTL) that have small effects. Discovery of additional genes will be essential in identifying the genes underlying these QTL and in understanding their function. At present, limited mechanistic knowledge limits our ability to understand these genes.
Optimal food production by plants requires a sufficient supply of soil nutrients, the most limiting of which is nitrogen. Sustained agricultural productivity has historically been maintained in the rich world by copious application of synthetic nitrogen fertilizers, with high cost to the economy and the environment. Unique among crop species, legumes produce their own nitrogen nutrient through a symbiosis with nitrogen-fixing bacteria collectively known as rhizobia. In this symbiosis, the bacteria convert molecular nitrogen into ammonia in exchange for host photosynthate. Studying the nitrogen-fixing symbiosis and fully explore its potential can boost the productivity of legume crops in the short term, and may expand this ability to non-legume crops over the long run. However, the nitrogen-fixing symbiosis is a complex system, and currently we know too few of the molecular players involved. This project will optimize two methods to reduce the activity of a given gene, and use these methods to screen for legume genes required for the function of the nitrogen-fixing symbiosis. The result of such endeavors should be a comprehensive list of legume genes playing critical roles in interacting with their rhizobial symbionts, and help unveal crucial biological processes in the interaction between plants and beneficial microbes.
This project addresses, via research and Extension, two important pests affecting tree-fruit and berry production in Massachusetts, the Plum Curculio and the Spotted Wing Drosophila. The main goal of this project is to evaluate the attractiveness of aromatic compounds to overwintered plum curculio and to other early season pests.
Current agricultural practices on available arable land will not meet the nutritional needs of a population that will reach nine billion people by the middle of this century (Ray et al. 2013). In parallel, climate change will increase extreme weather events, including drought (Dai, 2011, Trenberth et al., 2014), and continued urbanization of farmland is eliminating arable land (Song et al. 2015). There is a clear need for sustainable agricultural innovations that can increase yields and provide food security without incurring environmental degradation. Soil microbes are known to form associations with plants and affect plant health, and in recent years, interest has grown in exploiting the beneficial associations that plants establish with microbes. The plant microbiome abounds with plant growth-promoting rhizobacteria (PGPR) that can help plants acquire more nutrients from the soil and tolerate stressors like drought (Barnawal et al. 2013, Bresson et al. 2014). PGPR can also control plant pathogens (Chowdhury et al. 2013), promote beneficial mycorrhizal colonization (Labbe et al. 2014), and produce potentially valuable secondary metabolites (Raaijmakers et al. 2012). Finding ways to harness these beneficial microbes to improve crop growth and yield has the potential to ameliorate the challenges imposed by the world's growing population and environmental degradation.
Deficiencies of mineral content in human diets, a causal factor in rising rates of malnutrition worldwide, appear to derive from diminished contents of mineral nutrients in foods of plant or animal origins.This project will provide a foundation of data to help ascertain if the nutrient content of foods can be enhanced through selection of crop varieties and improved nutrition of crops and will assess how dietary habits affect mineral nutrition of humans.
Rootstocks are the most critical element in any orchard system. It controls disease and insect susceptibility, tree vigor, treeproductivity and fruit quality and maturation. Many new rootstocks become available annually, and our work evaluates those rootstocks under Massachusetts conditions. Compiled with evaluations from across North america, we are able then to make very good recommendations regarding rootstock use in orchard systems. Expected outcomes include increased orchard profitability and a general reduction in orchard canopy volume. the latter results in lower pesticide requirements. Further expected impacts include improved fruit quality.
Three temperate forage grass species (Lolium perrene, Festuca arundinacea, and Dactylis glomerata) will be grown in 6x10 ft plots under field conditions over the summer at the University of Massachusetts Crop and Animal Research and Education Farm in South Deerfield, Massachusetts. Each species will be grown in 10 replicates for a total of 30 plots. Five replicates of eachs pecies will be treated as well-watered controls and their soil moisture maintained above 25%, while the other five replicates will remain under a water-reduced treatment, receiving no rain or supplemental water. Water reduction will be imposed through the use of rain-out shelters. The shelters will have sides that could roll up and down in order to maintain ambient temperature and allow maximum air flow through the plots on dry days, but will be rolled down on rainy days to keep the water out. Water-reduction conditions will last for 10 weeks, after which rain shelters will be removed and rewatering begins over a period of three weeks in order to stepwise return soil moisture content to above 25%.
Microbial community composition: Throughout the water reduction period, bacterial communities will be sampled once a week for a total of 10 samples and an additional three times during the recovery period. Several mature but not senescent leaves will be collected from each plot for DNA extraction and bacterial cell counts in order to capture a representative community of the whole plot. Samples will be prepared for 16S rRNA sequencing using the Illumina MiSeq platform in two separate pools. Plant health measurements: To understand how bacterial communities change in relation to changes in the plant, several plant health measurements will be taken. Leaf relative water content, electrolyte leakage, chlorophyll, and soil moisture will be measured every week. Additionally, non-destructive biomass measurements will be taken periodically by measuring leaf height and plot coverage. Plot coverage will be estimated using an elevated quadrat device. At the end of the water reduction period, plots will be divided in half and destructive biomass sampling of one half will provide above ground fresh weight and dry weight measurements. Additionally, roots will be sampled in 15 cm increments to a depth of 60 cm. After soil removal roots will be dried and dry mass measured.
Nitrogen fixation rates by leaf microbes: Samples will be collected during field studies in the summer and used to quantify potential and actualized nitrogen fixation in the phyllosphere. Additional questions will be focused on understanding how phyllosphere BNF is impacted by plant host species, temporal dynamics, drought, and recovery. To determine the rate of BNF,stable isotope probing will be conducted at 6 different time points. Three samples will be taken during the drought period (week6, 7, 10) and three each week during recovery. Rate of nitrogen fixation will be determined by measuring incorporation of thestable isotope 15N into the leaf tissue. Leaf cuts of known area will be incubated in an artificial atmosphere containing 80% 15N and 20% O2 for 48 hours under ambient light and temperature. Corresponding control samples will be incubated under normal atmosphere to determine natural 15N abundance. After incubation, samples will be dried at 70°C, weighed, finely ground, and 1-2 mg of plant powder will be weighed in tin capsules and sent to a collaborator at the University of Vienna to determine 15N incorporation using a continuous-flow isotope ratio mass spectrometer. Nitrogen fixation rates can then be determined using the following equation where Nleaf is foliar N concentration, Mr is molecular weight of 15N, and t is incubation time:N2-Fix = Nleaf x (at%15Nsample - at%15Ncontrol)/100 x 103/Mr/tBacterial DNA samples corresponding to each timepoint will be taken to determine the absolute abundance of nitrogen fixing bacteria at each time point as well as to determine their taxonomic identity. The absolute quantity of nitrogen fixing bacteria per leaf area for each of the grass species and treatments will also be determined for the same time points using qPCR of the nifH gene. Next, the rate of nitrogen fixation per nifH copy number will be determined for each grass species under normal and water-stressed conditions. By comparing the three grass host species we will gain a better understanding of how phyllosphere BNF inputs are impacted by plant host species. By directly comparing rates under normal and stressed conditions we will understand how BNF will be influenced in the future by climate stress. Identification of nitrogen fixing members of the bacterial community will be achieved by sequencing the phylogenetic marker genes nifH using the Illumia MiSeq platform. nifH identity,diversity, and richness will be added to the models to better understand biological nitrogen fixation in the phyllosphere.
The herbal and botanical product market, estimated at more than US $60 billion in 2003, has been increasing at 6 to 8 % per year. According to the United Nations Comtrade Statistics, the estimated size of the global market for essential oils, fragrances, and flavors in 2013, was US $26 billion, growing an average rate of 8.1% in the past five years. The market for herbal dietary supplements in the United States has reached an estimated total of $6.4 billion, increasing by 6.85% in 2014 as compared with the previous year. Improvements in production of medicinal and aromatic plant products are needed to meet increased market demands.
Early studies have demonstrated that soil microorganisms associated with plant roots can improve plant growth and development through various mechanisms, including increasing available nutrients to plants, synthesizing phytohormones, inducing plant stress tolerance, and suppressing pathogens. Although the mechanisms are not fully understood, studies have demonstrated that the use of soil microorganisms (PGPRs) can promote synthesis of secondary metabolites in plants, improving the quality and value of the medicinal and aromatic plants. While commercial PGPRs and mycorrhizal fungi are available for various grain crops and vegetables in the United States, few of these products are available for medicinal and aromatic plants.
In the proposed study, PGPRs and mycorrhizal fungi will be studied for the growth and secondary metabolite synthesis in the Lamiaceae and other herbal families for their use in culinary and essential oil products. The development of PGPRs and mycorrhizal treatment that improve medicinal and aromatic plant yields and secondary metabolite production can lead to increased profits for growers and industries using natural products.
Literature on food composition demonstrates that the mineral nutrient density of vegetables has fallen in the past 50 years. This decline is associated with two factors: declines in soil fertility and with the genetics of plant cultivars that accumulate yield at higher rates than they accumulate mineral nutrients. This research is intended to help develop systems of food crop production that will supply adequate mineral nutrition to people directly through crop-derived foods.
Utilizing food systems to improve nutrition without the need for artificial fortification of food or use of dietary supplements of mineral nutrients is important in ending malnutrition. Malnutrition from deficiencies of mineral elements is reported to be on the rise worldwide, even in the United States. It is estimated that half of the world population suffers from incidences of mineral nutrient deficiencies. These deficiencies limit the physical, intellectual, and mental health activities of the affected people. The deficiencies appear to derive from diminished contents of mineral nutrients in foods of plant (vegetables, fruits) or animal (meats, milk, cheese) origins. With fruits and vegetables, the decline in nutrients is related in part to depletion of nutrients from soils without adequate replenishment with fertilization. Some of the diminished nutrient contents in fruits and vegetables may be related to genetics of new cultivated varieties of produce. Research is needed to develop systems of food crop production that will supply adequate mineral nutrition directly through crop-related foods and from meats and dairy products from livestock and poultry that are provided with adequate mineral nutrition. The research proposed under this project will provide a foundation of data obtained through field, greenhouse, and laboratory research to enable the investigators to pursue studies in planning sustainable food systems for human nutrition and crop production. The research will allow the investigators to obtain data that will help to ascertain if the nutrient content of vegetables and fruits can be enhanced through selection of crop varieties and improved nutrition of crops through fertilization and soil amendments.
This project has three components to increase sustainability in Massachusetts cranberry production:
- development and demonstration of sustainable practices for the management of the most severe pest problems: cranberry fruitworm, fruit rot disease, and the parasitic weed dodder.
- investigation of practices to conserve water and fuel.
- work with growers to implement nutrient management Best Management Practices (BMPs).
This research project seeks to develop better understanding of the iron homeostasis process in corn in order to address biofortification of staple foods with iron.
During estrus, mares can behave in a manner that can make handling, riding, training, or competing these horses difficult. Current methods to suppress estrus behavior during the breeding season, when most horse competition takes place, include: pharmacological treatments; glass marbles; and negative reinforcement. This work will develop strategies to control estrus behaviour without the need for pharmacological treatments or negative reinforcement.
Laminitis is a crippling disease that affects about one-percent of the more than nine million horses in North America, at a cost of over $1 billion annually. The goals of this project are to identify the specific metalloproteinases responsible, in hope of identification of inhibitors that can protect horses at risk.
This project, a component of a larger effort to annotate the bovine genome (define genes within the genetic code). One goal is to determine whether variations are associated with enhanced or decreased resistance to infectious diseases. We are interested in their receptors that detect the presence of infectious agents as well as the molecules these cells may produce to communicate with other cells in the immune system (known as cytokines or interleukins).
Evaluate pasture management systems with beef and other livestock.
Preventative and therapeutic reproductive management strategies...that are not drug-base will improve animal reproductive performance. This is a key part of sustaining an agricultural production system that is highly competitive in the global economy. The research proposed here will focus on several important areas. The team continues to conduct studies to identify novel genes and cell function that might contribute to predicting oocyte quality. The expression of factors that regulate luteal development, function, and regression are also central to improving female fertility in dairy and beef cattle. Likewise, environmental and metabolic stress negatively impact embryonic and fetal survival in cattle and sheep; and therefore, represent an additional area of research focus.
This project is intended to develop effective ways to keep fruit on trees until mature. It is also evaluating the effects of the methods on fruit quality and storage potential.
This project takes a theoretical and empirical approach to study how several aspects of the food supply chain affect the decisions of consumer and firms and their well-being. The research is examining three issues: buyer market power, the vertical structure of markets and benefits and costs associated with mandated labeling of food products.
This multidisciplinary project will promote the use of biochar and bio-oil generated from agricultural/forest organic wastes to enhance small farm sustainability through providing renewable fuel, and improving soil quality and crop productivity, and to improve the environment through sequestrating greenhouse gases and reducing the mobility and exposure of contaminants in soils.
In maize and the grass family, programmed cell death has a particular role to play in floral development. Maize flowers are initially hermaphroditic, but become either male or female through differential organ abortion. In male flowers, the female floral organs (the carpels) stop growing after they have formed, and eventually undergo programmed cell death. Programmed cell death in the carpels of the male maize floret is partially under the control of the transcription factor grassy tillers1. In gt1 mutants, the carpels in male flowers do not abort completely (Whipple et al.; Bartlett et al., 2015). However, gt1 mutant flowers are not fully hermaphroditic, indicating the existence of other genes that act with gt1 to regulate carpel abortion and programmed cell death. Which other genes are involved in carpel abortion? How do they interact with known sex determination genes in maize?
We have designed a series of genetic experiments geared at answering these questions. We will use mutant analysis to investigate whether gt1 is part of known sex determination pathways in maize. In addition, we have isolated four maize mutants where the gt1 mutant phenotype is strongly enhanced and programmed cell death in male flowers is disrupted. Using genetic and genomic tools, we will identify the genes that have been disrupted in these mutants, and work to determine their precise roles in mediating growth repression and programmed cell death.
This research will examine possible affects of climate change on certain agricultural crop plants. It will include experiments that will allow prediction of how alfalfa plants will respond to future elevated CO2 (800ppm) and elevated ozone (O3) (80ppb).
This project will examine the effect of natural diversity on biofuel production efficiency by using a grass energy model organism (Brachypodium distachyon), and treatment with both biological and thermochemical conversion.
Pathogens and parasites including viruses and protozoa are known to be major contributors in the decline of honeybee colonies, yet we know very little about epizootiology of these agents. A primary reason for this lack of knowledge is the microscopic and submicroscopic nature of these bee pathogens. As part of our research we have developed and are continuing to develop molecular methods that allow us to detect and monitor the prevalence and spread of these infectious agents in bee populations. In addition we will be exploring the utility of small bio-reactive molecules for use in controlling viruses and protozoan pathogens without harming bees.
Armored scale insects (Hemiptera: Diaspididae) include many destructive pests of orchard crops, forestry, horticulture, and agriculture (Kennett et al., 1990), costing an estimated two billion dollars per year in the US (Miller & Davidson, 2005). They also have an extraordinary tendency to be invasive. As of 2005, the US had 132 species of diaspidids introduced from other countries (Miller et al., 2005), comprising fully 40% of the known US armored scale insect fauna. Of these, 85 (64%) were considered pests. About one new invasive diaspidid species is detected in the US every year (Miller et al., 2005). Here in Massachusetts, multiple species of armored scale insects are emerging as serious pests of cranberries (Averill & Sylvia, 2017). One specific target of this investigation will be the scale insect that have recently emerged as a threat to Massachusetts cranberry. Some armored scale insect pest species have been recorded from an enormous range of hosts. For instance there are 23 armored scale insect species that have each been found on over 50 different host plant families -- remarkable examples of extreme generalism (García Morales et al., 2016). It has been suggested that these are not true generalist species but instead are clouds of similar-looking specialist species (Loxdale et al., 2011). The goal of this project is to assess species boundaries within wide-ranging extreme-generalist armored scale insect pest complexes, in particular including the Chrysomphalus dictyospermi/pinnulifer complex, the Hemiberlesia palmae/cyanophylli complex, and the Selenaspidus articulatus complex. Each of these includes at least one globally invasive species, and for each we already have extensive samples from multiple hosts within the native range. We will sequence a sample of each insect's genome and using modern analytical methods to distinguish the species. We will assess the geographic range and host range of each species, and assess which are pests, which are potential invasive pests, and which are non-pests. We will seek morphological diagnostic characters and describe the new species in cases when it is practical to do so. We w ll publish our results in the peer-reviewed literature and present them at national and international entomology conferences.
Pollen grains germinate on the stigma, the receptive surface of the female organ pistil. Each pollen grain hydrates and extrudes a pollen tube whose function is to transport two sperm cells carried in its cytoplasm to the female gametophyte inside an ovule, usually located at some distance from the stigma. Recent research in plant reproduction has produced critical insights into how a pollen tube targets the female gametophyte (where the egg apparatus is located) through a female-guided process and how the pollen tube, once inside the female gametophyte, achieves sperm release to enable fertilization. Yet mechanisms that underlie the critical first pollen-pistil interactive steps on the stigma, i.e. adhesion of pollen grains on the stigma, pollen hydration, activation and extrusion of the pollen tube to penetrate the stigmatic tissue, remain unclear. The project utilizes the model plant Arabidopsis to elucidate how these early events are orchestrated. In particular, we examine the contribution by three related receptor kinases (RKs) expressed in the stigma, FERONIA (FER), HERCULES1 (HERK1) and RK7.
This project addresses environmental concerns and profitability issues faced bu livestock farms. It is evaluating options for cover crops and for pasture management.
Identify land-grant universities, the BLM and others entities involved in sustainable management of feral equids, to collaborate and find solutions for a balanced coexistance of feral and domestic populations.
Goals / Objectives
Integrate existing biological, ecological and economic data to make comprehensive science-based recommendations for the BLM Wild Horse and Burro Advisory Board for sustainable management of wild and free-roaming horses and burros and the rangelands they inhabit.
Identify areas for future collaboration between land-grant universities and the BLM and others for sustainable management of wild and free-roaming horses and burros and the rangeland they inhabit.