Though usually a nuisance in swimming pools and ponds, algae has the potential to be a valuable commodity for use as food and fuel. But before algae butter and biofuel become commonplace, issues with harvesting and storing this new crop need to be overcome. Though there has been ample research into how to grow and use algae, scientists have spent little time figuring out what to do after you pull it out of the water and before you eat it (or turn it into biodiesel). Algae, like all food products, starts to spoil as soon as it is harvested. This study looked at three methods of preserving algae, freezing, drying, and pasteurization. Freezing is a good method for preserving fats and proteins, but it is expensive to freeze tons of algae. Freezing and thawing destroyed the algal cells, producing a soupy mixture that may cause complications for processing into foods or fuels. Drying was able to preserve the fats in algae, but only if it was dried just the right amount, about as dry as cheese or ham. Pasteurization was able to prevent the oils in the algae from going rancid by inactivating a protein in the algae that causes the oil to spoil rapidly. Overall, this research is an initial step in finding a process to produce a shelf stable algal commodity, opening the door to new and valuable products for human use.

Wheat is the most important cereal crop of the world, and one of the most serious diseases affecting it over much of its range is covered smut or bunt (57). The word "bunt", according to Heald (48), is a contraction of an old English term, "burnt ear", which fittingly describes the ravages of covered smut.

Warm-season turf species are becoming increasingly popular for putting green use in the transition zone. Ultradwarf bermudagrass (Cynodon dactylon (L.)  C. transvaalensis Burtt-Davy) is the prevalent warm-season putting green species, but seashore paspalum (Paspalum vaginatum Swartz) and ‘Diamond’ zoysiagrass [Zoysia matrella (L.) Merr.] may also be grown in the transition zone. Warm-season species are susceptible to winter injury and may require different management regimes than cool-season species. Therefore, the objectives of this research were to assess the impacts of various management practices on warm-season putting green species and characterize the physiological basis for differences in freeze tolerance of various warm-season putting green species. Field studies determined sampling procedures form thatch-mat depth and soil organic matter content of warm-season putting greens and assessed the impact of various management practices on different warm-season putting green species/varieties. The relative freeze tolerance of ‘Champion’ and ‘TifEagle’ ultradwarf bermudagrass cultivars, ‘SeaDwarf’ seashore paspalum, and Diamond zoysiagrass were determined, along with the accumulation of proline and polyamines during cold acclimation, in growth chamber studies. All species/varieties required different sampling numbers for determination of thatch-mat depth and soil organic matter. More sand was incorporated into the turf canopy and surface hardness was increased with brushing and vibratory rolling TifEagle putting greens after sand topdressing application than either treatment alone. Putting green management programs with lower mowing heights and increased mowing frequencies increased ball roll distance on a MiniVerde putting green without negatively affecting turf quality. Weekly vertical mowing + daily grooming on TifEagle reduced thatch depth and turfgrass quality, while increasing topdressing incorporation over either treatment alone. Diamond was the most freeze tolerant species/variety, followed by TifEagle, Champion, then SeaDwarf. Cold acclimation increased proline concentration for all species/varieties except SeaDwarf, but had inconsistent effects on polyamines. Spermidine and putrescine concentrations differed with species/variety, but were not correlated to freeze tolerance.

Common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass [C. dactylon (L.) Pers. X C. transvaalensis Burtt-Davy] are some of the most common turfgrasses used on athletic fields. Subsequently, the traffic tolerance of commercially available cultivars and the effects of trinexapac-ethyl (TE) on bermudagrass athletic fields with or without perennial ryegrass are often limited. A two year study at the University of Tennessee was conducted under simulated athletic field traffic to evaluate the performance of bermudagrass cultivars as affected by TE and overseeding. Bermudagrass cultivars evaluated were Tifway, Riviera, Patriot, and Celebration. TE treatments consisted of an untreated control, TE at 76.3 g a.i. ha-1 every 14 days until 14 days prior to trafficking (TE A), and TE at 76.3 g a.i. ha-1 every 14 days until 14 days after trafficking (TE B). Overseeding treatments consisted of no overseeding and overseeding at 670 kg ha-1 of perennial ryegrass (Lolium perenne L.). Plots were rated for percent green cover using digital image analysis after every 5 traffic events. Soil physical characteristic measurements were performed after every traffic season. Morphological data was determined by measuring number of leaves, internode lengths, leaf angle, and leaf width of the bermudagrass. Cultivar was significant for percent green cover for both years of this study with Tifway and Celebration having the highest ratings and Patriot having the lowest rating. TE was also significant for percent green cover for the first 10 traffic events with TE treatment B having lower percent cover values. Morphological characteristic was significant for leaf angle for both years of the study. A more vertical leaf angle to the shoot occurred in the more traffic resistant cultivars Tifway and Celebration. Finally, both TE treatments yielded higher percent green cover values in 2008 when morphological characteristic data was collected and a more vertical leaf angle to the shoot occurred compared to the untreated control. Tifway, Celebration, and Riviera when applied with trinexapac-ethyl before the traffic season and overseeded with perennial ryegrass would be beneficial for athletic field managers.

Conservation tillage programs have been successfully implemented for many agronomic cropping systems, but adoption of reduced tillage for vegetable crops has been slow. As many conventionally managed conservation tillage programs rely on synthetic herbicides for clean cultivation, alternative methods must be devised to suppress weed pressure and reduce reliance on mechanical cultivation to aid in the development of reduced tillage programs for organic cropping system. Strip tillage is a reduced tillage method that is well suited to vegetable crop production, and the utilization of cover crops and living mulches between rows provides a viable weed management option for organic systems. The adoption of reduced tillage and the inclusion of cover crops and living mulches have the potential to alter the agroecosystem in ways that impact plant development and crop yield, and augment weed, insect and disease pressure. The current study focuses on the use of strip tillage and the interplanting of spring-seeded living mulches and overwintered cover crops for early-season organic broccoli production. Data were collected on ground cover provided by cover crops and living mulches, crop physiological status (petiole sap nitrate, photosynthetic rate, plant growth and crop biomass) and pest pressure (weed relative abundance, insect density and disease incidence and severity). Living mulches provided the greatest ground coverage when cover crop establishment was poor; however, when cover crops produced a large amount of biomass, living mulch establishment was suppressed. Decreases in herbivorous pests and suppression of grassy and cool-season weed species were also observed, indicating that strip tillage and the use of spring-seeded living mulches and overwintered cover crops may provide beneficial pest management strategies. Decreases in crop growth and biomass, and decreases in petiole sap nitrate were observed, however, indicating reductions in crop vigor and yield may be expected with the implementation of strip tillage and living mulch crops. It is suggested that the utilization of strip tillage and living mulch crops may provide benefits to pest management which may outweigh declines in yield.

Field and labratory studies were conducted to determine the efficacy of saflufenacil alone and with mixture partners for burndown. Field studies were conducted in 2009 and 2010 to evaluate saflufenacil in mixtures with glyphosate, glufosinate, or paraquat for control of glyphosate-resistant (GR) horseweed prior to planting cotton. Saflufenacil and saflufenacil mixtures were applied 7 days before planting (DBP). Saflufenacil at 25 and 50 g ai ha-1 in mixture with all three non-selective herbicides provided similar GR horseweed control when compared to the current standard of glyphosate plus dicamba. Control of GR horseweed was also not different at the 25 and 50 g ai ha-1 of saflufenacil across all mixtures from the standard of glyphosate plus dicamba. Laboratory studies were initiated to determine the uptake and translocation of saflufenacil alone and when mixed with glyphosate and paraquat. It was found that glyphosate plus saflufenacil had a greater absorption of saflufenacil at 2 and 8 HAT. By 24 HAT there were not any differences between the amount of saflufenacil absorbed into GR horseweed between treatments. Translocation data also confirmed that the majority of saflufenacil stayed in the treated leaf at 72 HAT.

Switchgrass, Panicum virgatum, is being developed as an economically and ecologically sustainable biomass crop. Nitrogen is considered one of the most limiting inputs of switchgrass. Alternatives to synthetic nitrogen fertilization may be nitrogen-fixing legumes interseeded into switchgrass. The objectives of this research were: (1) develop efficient legume management strategies for switchgrass production systems, (2) evaluate and identify cool and warm-season legumes that can be grown compatibly with switchgrass, (3) determine whether switchgrass yields are increased by legume N-fixation, and (4) determine N-fixation of common (Vicia sativa) and hairy vetch (Vicia villosa). This study examined the establishment and persistence of ten different legume species in ‘Alamo’, a lowland variety of switchgrass in two switchgrass production systems: a one-cut biomass harvest and a two-cut forage/biomass harvest. Cool-season legumes were alfalfa (Medicago sativa), arrowleaf clover (Trifolium vesiculosum), common vetch, crown vetch (Securigera varia), red clover (Trifolium pretense), hairy vetch, and crimson clover (Trifolium incarnatum). Warm-season legumes were Illinois bundle flower (Desmanthus illinoensis), trailing wild bean (Strophostyles helvula), and partridge pea (Chamaechrista fasciculata). Red clover showed the highest plant densities and increase in switchgrass yields when interseeded into existing switchgrass stands in both harvest systems. Crude protein levels were highest in the 135 kg N ha-1 treatment in the forage cut of the two-cut harvest system. Arrowleaf clover, crimson clover, and red clover had high stand densities with annual reseeding. A combination of cool-season legumes, crimson clover and common vetch, in combination with warm-season partridge pea, were established in existing switchgrass stands after one year. Common vetch was evaluated for its nitrogen fixing capacity, seed germination, establishment, and effects on yield of switchgrass. Scarification by sulfuric acid had higher seed germination than other scarification treatments, except 100 grit sandpaper treatment for one minute at 0.7 kg of pressure. Common and hairy vetch nitrogen contributions were 59.3 and 43.3 kg N ha-1 respectively at seeding rates of 6.7 kg PLS ha-1. Switchgrass yields can increase with common and hairy vetch seeding rates of 7.6 and 10.4 kg PLS ha-1 to achieve 67 kg N ha-1, the recommended rate of N-fertilization for switchgrass stands.

Dark tobacco (Nicotiana tabacum L.) has historically been produced usingconventional tillage practices. Soil is cultivated multiple times throughout a growing season leading to an increased incidence of soil erosion. No-till systems have been growing in popularity with the advent of new technology that has enabled the practice to be performed effectively and efficiently. With the recent expansion of no-till practices throughout the agricultural community, many crops have had success in producing comparable yields while reducing input costs and saving soil resources. For this experiment, a traditional tobacco transplanter was modified for use in a no-till environment. All modifications were fabricated without using specialty tools and made possible to be removed if desired or necessary. Frame extensions were designed and built to accommodate row cleaners and coulters. Tillage shanks were also added to aid in optimal furrow formation. Double-disc opening shoes replaced the original round point shoes and the curved edges of the rear drive wheels were removed, creating a flat surface to increase soil contact. Experimental no-till plots in fescue sod and soybean chaff residues were conducted alongside conventional tillage plots at the Western Kentucky University Agricultural Research and Education Complex in summer 2011. Five treatments, one conventionally tilled (Conv) and four no-till, were replicated three times within a randomized complete block design and used to determine the efficacy of transplanter modifications (consistency of depth, furrow closure, observed plant damage), survival of the transplants, and the amount of residue displacement. The four no-till treatments utilized different combinations including: coulter, row cleaner and shank (CRS), row cleaner and shank (RS), coulter and shank (CS), and shank only (S). These treatments demonstrated the functionality of each combination in comparison to conventional treatments. No treatment performed equally well in both residue locations. Plots in fescue residue utilizing a combination of coulter, row cleaner, shank (CRS), exhibited the lowest amount of root exposure, highest survival rate, and comparable cured weight when compared to conventionally tilled treatments. In soybean residue plots, the treatment operating with row cleaners and shanks (RS) had equivalent amounts of furrow closure to conventionally tilled plots. Pairing specific modification combinations with previous crop residue can provide furrow closure, transplant survival, and cured yield equivalent to conventionally tilled dark tobacco.

Common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass [C. dactylon (L.) Pers. X C. transvaalensis Burtt-Davy] are some of the most common turfgrasses used on athletic fields. Subsequently, the traffic tolerance of commercially available cultivars and the effects of trinexapac-ethyl (TE) on bermudagrass athletic fields with or without perennial ryegrass are often limited. A two year study at the University of Tennessee was conducted under simulated athletic field traffic to evaluate the performance of bermudagrass cultivars as affected by TE and overseeding. Bermudagrass cultivars evaluated were Tifway, Riviera, Patriot, and Celebration. TE treatments consisted of an untreated control, TE at 76.3 g a.i. ha-1 every 14 days until 14 days prior to trafficking (TE A), and TE at 76.3 g a.i. ha-1 every 14 days until 14 days after trafficking (TE B). Overseeding treatments consisted of no overseeding and overseeding at 670 kg ha-1 of perennial ryegrass (Lolium perenne L.). Plots were rated for percent green cover using digital image analysis after every 5 traffic events. Soil physical characteristic measurements were performed after every traffic season. Morphological data was determined by measuring number of leaves, internode lengths, leaf angle, and leaf width of the bermudagrass. Cultivar was significant for percent green cover for both years of this study with Tifway and Celebration having the highest ratings and Patriot having the lowest rating. TE was also significant for percent green cover for the first 10 traffic events with TE treatment B having lower percent cover values. Morphological characteristic was significant for leaf angle for both years of the study. A more vertical leaf angle to the shoot occurred in the more traffic resistant cultivars Tifway and Celebration. Finally, both TE treatments yielded higher percent green cover values in 2008 when morphological characteristic data was collected and a more vertical leaf angle to the shoot occurred compared to the untreated control. Tifway, Celebration, and Riviera when applied with trinexapac-ethyl before the traffic season and overseeded with perennial ryegrass would be beneficial for athletic field managers.

In an effort to maximize yields, many soybean growers have begun moving to intensive, input-based soybean management systems. However, limited reliable information exists about the effect of these inputs on soybean yield. The purpose of this study was to evaluate the effect of individual inputs and combinations of inputs as part of high-yield management systems on soybean seed yield and to determine the effect of one of these inputs, lactofen, on soybean physiology. Small plot studies were established in nine states across the Midwest. A number of commercially available soybean inputs were evaluated individually and in combination to determine their effect on soybean yield and quality. Lactofen and comparison treatments were applied to soybeans at multiple growth stages and yield and yield components were determined. When examined across environments, input-intensive combination treatments increased soybean yields from 3.9 to 8.1 %. However, break-even economic analysis indicated that the combination (SOYA) treatments evaluated had 0% probability of breaking across a wide range of yield levels and soybean prices, due to the high input costs. The foliar insecticide showed the highest probability of breaking even across a range of yield levels and crop prices (40% to 99%). Yield increases and breakeven probabilities were generally greatest in the northern states (Minnesota, Wisconsin, Michigan) and similar in the central and southern states. Lactofen application did not kill the apical meristem and had minimal effect on yield components compared to untreated soybeans at any growth stage. Meristem removal increased node m-2 in some environments, but did not increase pods m-2 and seeds m-2 or seed yield.