Completed Research Projects

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.

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.

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.

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.

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 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 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.

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.

 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.

Due to the freeze on the night of May 18th, many fruits were severely injured and subsequent thinners were either not applied or, if they were, used at low rates. It was observed that many fruits had a reduced number of seeds, however fruit harvested were very large. This project is to see if a relationship between seed number and fruit size exists. At normal harvest, large fruits were selected and fruit was weighed. Fruit diameter and the number of aborted and viable seeds were recorded for each apple. There was no correlation between fruit size and seed num

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.

Non-point source pollution including excess nutrients, organic particles, fecal coliform bacteria, and additional pathogens is considered high risk at many animal operations, especially equine facilities. A common issue in these animal facilities is overgrazing which is the main cause of mud, resulting in serious threats to the environment as well as to animals and humans.  In addition, most equine facilities are regularly faced with a major challenge related to the large amount of manure produced by animals at the facility. Some of the challenges related to manure include 1) lack of manure storage 2) close proximity of manure pile(s) to nearby water bodies 3) animals' direct access to streams and other bodies of water, 4) undesirable characteristics of horse manure due to exceptionally high C:N ratio which makes the waste unusable for agriculture uses. In Massachusetts, there are estimated to be over 26,000 domesticated horses within the state. There are roughly 50,000 acres of land being used in MA for equine operations, therefore, there are about two horses for every acre of dedicated land- which is one fourth of the current recommended practice. It is estimated on average one 1,000 lb. horse will produce approximately 9 tons of manure. When including bedding, stall waste could be as much as 12 tons per horse per year. Managing this waste properly is a growing challenge for equine facilities, especially at places where land availability is limited, and the horses are kept in small acreage and stalls. Runoff from the stables to high traffic areas, manure piles, and unmanaged and overgrazed pastures are the main contributing factors to environmental degradation. Many horse owners do not have enough resources and background to make significant changes in their current practices including pasture, mud, and nutrient management. This provides opportunity for conducting research on various aspects of pasture management, manure management and provides information to remediate the negative impacts of equines on the environment.

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.

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.

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.

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.

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.

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).

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.

Plant diseases cause crop loss, reduce food production and threaten global food security (Savary et al., 2012). Focusing on two distinct pathosystems that cause Fusarium vascular wilts and the Basil downy mildew (BDM), respectively, we propose to establish a pipeline to dissect host-pathogen interactions and provide novel means to develop disease resistant cultivars in order to manage plant diseases that threaten food security.

The relationship between domesticated animals and humans is a close one, and has existed for at least ten thousand years. It is important to understand the immune defenses of many animals, in addition to the immune defenses of humans and mice. The goal of our project is is characterize the genetic diversity of a family of immune receptors in domesticated animals and use this information for selective breeding and the design of better vaccines.

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 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.

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.