bluuebunny/crossref_metadata_2025 huggingface dataset:
Incorporating Organic and Agroecological Approaches into the University Curricula: The Iowa State University Graduate Program in Sustainable Agriculture
Authors: Delate K.
Published: December 2018

Organic agriculture has expanded to a $13 billion industry in the United States in 2005, continuing the nearly decade-long trend of 20% annual growth. Despite the growth in organic agriculture, our scientific knowledge of organic agriculture farming systems remains limited. Interest in sustainable and organic education at the university level has increased in recent years. To help address this need, the Iowa State University Graduate Program in Sustainable Agriculture (GPSA) was established in 2001 to meet three principal objectives: 1) provide students with the analytical and problem-solving skills required to meet the challenges confronting agriculture in the 21st century; 2) develop an innovative interdisciplinary and interdepartmental approach to graduate education; and 3) position Iowa State University at the forefront of institutions conducting research and extending knowledge about sustainable agricultural systems. As of 2004, more than 70 faculty from various departments and 29 students have participated in the program. Students have the opportunity to investigate organic issues within the context of the five new GPSA courses and to conduct organic agriculture farming systems research in thesis and dissertation studies. Producers and agricultural professionals are involved with GPSA students through the curriculum and on-farm research. Research questions involving optimizing crop or livestock production, plant protection, soil quality, and socioeconomic benefits of farming systems constitute typical theses.
Does Organic Production Enhance Phytochemical Content of Fruit and Vegetables? Current Knowledge and Prospects for Research
Authors: Zhao Xin , Rajashekar C.B. , Carey Edward E. , Wang Weiqun
Published: December 2018

Demand for organically grown produce is increasing, largely due to concerns of consumers about health and nutrition. Previous studies have not shown a consistent difference of essential nutrients, such as vitamins and minerals, between organic food crops and the conventional counterparts. However, to date, little consideration has been given to phytochemicals, secondary plant metabolites with potential health-promoting properties. We first discuss factors that can infl uence the levels of phytochemicals in crops, and then we critically review the results of published studies that have compared the effects of organic and conventional production systems on phytochemical contents of fruit and vegetables. The evidence overall seems in favor of enhancement of phytochemical content in organically grown produce, but there has been little systematic study of the factors that may contribute to increased phytochemical content in organic crops. It remains to be seen whether consistent differences will be found, and the extent to which biotic and abiotic stresses, and other factors such as soil biology, contribute to those differences. Problems associated with most studies tend to weaken the validity of comparisons. Given the limitations of most published studies, needs for future research are discussed.
Effect of Amended Backfill Soils When Planting Five Species of Palms
Authors: Hodel Donald R. , Beaudoin Peter J. , Downer A. James , Pittenger Dennis R.
Published: December 2018

In a study in southern California, five species of palms [king palm (Archontophoenix cunninghamiana), mediterranean fan palm (Chamaerops humilis), queen palm (Syagrus romanzoffiana), windmill palm (Trachycarpus fortunei), california fan palm (Washingtonia filifera)] grown in 1-gal containers were planted in 12 × 12 × 12-inch holes in sandy loam (five species) and in clay loam (two species) with the backfill amended using a commercially available, composted, nitrogen-stabilized douglas fir (Pseudotsuga menziesii) shavings product incorporated at 0%, 25%, and 50% by volume. After 18 months, all palms were fully established. Crown volume, stem diameter, visual quality, quantity of new leaves produced, and percent total nitrogen, potassium, and magnesium in leaves did not differ significantly among the three treatments for all species or among treatments within a species. Thus, in this study there was no benefit from amending the backfill with this type of organic amendment when planting palms.
Economic Assessment of Irrigation Management in Muscadine Grapes
Authors: Carpio Carlos , NeSmith D. Scott
Published: December 2018

This study evaluates the effect of irrigation on the profitability of the muscadine grape (Vitis rotundifilia) operation. Data from a 3-year experiment in which muscadine grapes were grown under four irrigation regimes were used to establish the relationship between yields and irrigation. Assuming a muscadine fruit price of $0.50/lb, harvesting costs of $0.21/lb, and irrigation costs of $16.75/acre-inch, the profit-maximizing level of irrigation was estimated to be 13.1 acre-inches for a season, or 7 gal/day per plant. Water requirements for profit maximization are 9% lower than water requirements for yield maximizing. Moreover, it is concluded that the effect of an adequate use of irrigation in the profitability of the muscadine grape operation can be substantial.
Uniformity of Sand Deposition on Cranberry Farms and Implications for Swamp Dodder Control
Authors: Hunsberger Laura K. , DeMoranville Carolyn J. , Sandler Hilary A. , Autio Wesley R.
Published: December 2018

Uniformity of sand deposition on cranberry (Vaccinium macrocarpon) farms was examined to evaluate the potential use of two sanding methods to suppress swamp dodder (Cuscuta gronovii) seedling emergence by seed burial. During a 2-year study, 24 farms were evaluated with sand applied by either water barge or directly on ice. To measure the depth of sand deposited on the surface, soil cores were taken every 5 m in a grid pattern on a randomly selected portion of a commercial Massachusetts cranberry farm. Both application methods delivered nonuniform depositions of sand with the majority of the samples measuring less than the target depth. Surface diagrams depicting sand depths indicated no particular patterns of error or deposition that could be advantageously adjusted by the grower at the time of application. Mean actual: target depth ratios were 63% and 66% for barge and ice sanding, respectively (100% indicating actual equaled target). In the best scenario (two farms), 47% of the sanded area received less than the target amount; 11 farms had at least 90% of actual sand depths below the target depth. For farmers targeting 25-mm sand depths (depth expected to suppress dodder germination), the mean actual: target depth ratio was 58%, indicating half of the actual sand depths measured less than 15 mm. Compaction of the sand layer due to the elapsed time period (6 weeks or more) between sand application and measurement may have contributed to the large number of samples that were lower than the target depth. Even so, the irregularity of deposition patterns and the large proportion of sand depths that were less than 25 mm indicated adequate suppression of dodder seedling emergence would be unlikely with either sanding method.
Response of Rockwool-grown Greenhouse Cucumber, Tomato, and Pepper to Kinetin Foliar Sprays
Authors: Papadopoulos A.P. , Saha U. , Hao X. , Khosla S.
Published: December 2018

Encouraging results from previous trials on field vegetables led to the expectation that a kinetin foliar spray from the commercial product KIN-Gro (5000 ppm kinetin) on greenhouse vegetables would positively affect their growth and productivity. Thus, in this study, we evaluated the usefulness of this product on rockwool-grown `Bodega' cucumber (Cucumis sativus), `Rapsodie' tomato (Lycopersicum esculentum), and `4-Ever' and `444' pepper (Capsicum annuum) at the Greenhouse and Processing Crops Research Centre of Agriculture and Agri-Food Canada, Harrow, Ont. Two replicated experiments were conducted to study the effect of kinetin spray on growth and production of all three crops: the first in Spring-Summer 2004 and the second in Fall-Winter 2004. Foliar sprays of kinetin at 2.5, 5, and 10 ppm concentrations were tested against a water spray (control) on each crop. A 2.5-ppm kinetin spray had beneficial effects on the growth of cucumber transplants (taller plants and greater leaf area and fresh weight of leaves and stems). Furthermore, this treatment resulted in higher marketable yield in the Spring-Summer crop and in larger fruit size in the Fall-Winter crop. Regression analysis showed that cucumber marketable yield had an overall quadratic response to kinetin spray concentration in Spring-Summer season maximizing at 5.1 ppm kinetin. Kinetin spray also had beneficial effects on the growth of tomato seedlings, but not on yield. On the other hand, significant beneficial effects were observed on the growth of pepper seedlings and on marketable yield and fruit quality. Regression analysis showed that the response of pepper marketable yield to kinetin spray concentration was positive and linear. It must be noted that, given the rather short-term nature of our experiments, the observed beneficial effects of the kinetin sprays on yield can only be interpreted as beneficial effects on early yield rather than on the total yield. We concluded that under our growing conditions, cucumber production would benefit from a dilute (2.5 ppm) kinetin spray, and pepper production from a high concentration spray (10 ppm); tomato transplant growth will also benefit from a kinetin spray at 2.5 ppm. The results of this study could be of considerable significance to the greenhouse vegetable industry.
Flower Bud Mortality and Salt Levels in Highbush Blueberry Fields Adjacent to Michigan Highways Treated with Deicing Salt
Authors: Berkheimer Steven F. , Hanson Eric J. , Potter Jason K. , Andresen Jeffrey A.
Published: December 2018

Some highbush blueberry (Vaccinium corymbosum) fields adjacent to Michigan roads exhibit abnormally high levels of winter fl ower bud mortality and twig dieback, even following relatively mild winters. This work was conducted to determine if this injury was caused by deicing salts (primarily sodium chloride) that are applied to adjacent roads and blown by the wind onto bushes. Flower bud mortality was recorded in the spring at several locations within six farms adjacent to divided highways treated with deicing salts. Four farms were east of highways (downwind of prevailing wind direction) and two were west (upwind) of highways. Each May for 3 years, the numbers of live and dead fl ower buds were counted on plants located varying distances from the highway. Bush position and distance from the highway were determined with global positioning system (GPS) equipment. Bud health was also assessed monthly during the winter. In fields located downwind of highways, bud mortality was consistently greatest close to the road and decreased with distance. Salt had an apparent effect on mortality 60 to 120 m from the highway, depending on the year. In fields west or upwind of highways, bud mortality was not consistently related to distance from the highway. Flower bud injury was evident by mid-January, and increased throughout the winter. Results indicated that wind-blown salt spray can cause considerable injury in blueberry fields close to salted roads.
Maintaining Fruit Firmness of `McIntosh' and `Cortland' Apples with Aminoethoxyvinylglycine and 1-Methylcyclopropene during Storage
Authors: Moran Renae E.
Published: December 2018

The goal of this project was to evaluate the effectiveness of aminoethoxyvinylglycine (AVG) for increasing effectiveness of 1-methylcyclopropene (1-MCP) for maintaining firmness and preventing scald in `McIntosh' and `Cortland' apples (Malus ×domestica). AVG and 1-MCP used together maintained `McIntosh' apple firmness more than 1-MCP used alone after 120 or 200 days of controlled-atmosphere (CA) storage. AVG and 1-MCP can be used to maintain firmness of `McIntosh' when internal ethylene concentration (IEC) at harvest is as high as 240 μL·L-1, but CA storage life is limited to 4 months. AVG was not effective at increasing efficacy of 1-MCP on `Cortland' when IEC at harvest was not significantly different between AVG-treated and untreated fruit and IEC was less than 2 μL·L-1. AVG increased efficacy of 1-MCP on `Cortland' when IEC was 36 μL·L-1 in untreated fruit compared to undetectable in AVG treated fruit. 1-MCP prevented scald of `Cortland' in 1 year and reduced it to 5% or less in another year when fruit were stored 120 days. 1-MCP reduced `Cortland' scald to 34% or less after 200 days of storage.
Anatomical and Morphological Characteristics of Laser Etching Depressions for Fruit Labeling
Authors: Etxeberria Ed , Miller William M. , Achor Diann
Published: December 2018

Fruit etching is an alterative means to label produce. Laser beam-generated pinhole depressions form dot-matrix alphanumerical characters that etch in the required price-look-up information. Pinhole depressions can disrupt the cuticular and epidermal barriers, potentially weakening the natural protection against pathogens. In the present study we describe the anatomical and morphological characteristics of the pinhole depressions in the cuticle/epidermis, and the changes taking place during storage of two fruits: avocado (Persea americana) and tomato (Lycopersicon esculentum). These fruits represent the extremes from a thick, non-edible peel to a thin edible peel. On both tomato and avocado, etching depressions were fairly similar in diameter and depth, averaging 200 μm and 25 μm, respectively, for energy impact durations of 30 μs for tomato and 45 μs for avocado. Immediately after etching, the two- to five-cell-deep depressions contained cuticle/wax deposits. Additional cuticle/wax material was deposited in and around the depressions during storage as demonstrated by confocal, fl uorescent, and light microscopy. In addition, the cells underlining the etch depression increased phenolic and lignin deposits in their walls, creating a potential barrier against pathogenic organisms.
Review of Granular Applicators for Turfgrass
Authors: Parish Richard L.
Published: December 2018

Application of granular materials is an important part of most turfgrass maintenance programs, but is not often studied by horticulturists. Agricultural engineers have conducted many research studies over the past 50 years on the theory, testing, and use of granular applicators. Understanding the theory of granular distribution can aid horticulturists and turfgrass professionals in the effective use of spreaders. This article will review relevant engineering studies and interpret some of the results to provide help in using spreaders more effectively. Proper operating mode, proper pattern adjustment, and the use of an appropriate swath width can greatly improve pattern uniformity. For instance, a half-width pattern has been proven more effective at pattern improvement than right-angle patterns, and the detrimental effect of humidity on spreader pattern has been demonstrated.
Consumer Survey of Selected Garden Chrysanthemum Cultivars in Mississippi
Authors: Posadas Benedict C. , Coker Christine H. , Knight Patricia R. , Fain Glenn
Published: December 2018

The objective of this survey was to determine the levels of liking and willingness to pay for selected garden chrysanthemum (Dendranthema ×grandiflorum) cultivars, and to measure relative infl uence of socioeconomic characteristics on consumer preferences and valuations. The survey was conducted during the 2003 Fall Flower and Garden Fest at the Truck Crops Experiment Station in Crystal Springs, Miss. Nine garden chrysanthemum cultivars were presented to 579 survey participants in three pot sizes. Respondents preferred `Mithra Maroon', `Venus Purple', `Amory Yellow White', `Adonis Purple', and `Road Runner Bronze' more than `Night Hawk Lemon', `Freya Salmon', `Amata Purple', and `Starlet Ivory'. Of the five preferred cultivars, however, respondents were willing to pay more for `Mithra Maroon', `Road Runner Bronze', and `Amory Yellow White'. Consumers of White or Caucasian origin liked the cultivars less and were willing to pay less for them as compared to other respondents who reported other racial origins, primarily Native Americans and African Americans. The levels of liking for the cultivars were similar for participants of different gender classification, but female respondents were willing to pay more for the cultivars. Respondents who previously bought chrysanthemums reported higher level of liking for the cultivars but were not willing to pay more for them. Participants who were interviewed on Saturday liked the cultivars more but were willing to pay less than those who were interviewed on Friday. Larger-sized households tended to like the cultivars less and were not willing to pay more for the cultivars. Respondents did not like the cultivars in larger-sized pots and were not willing to pay more for plants in larger-sized pots included in the survey.
Gaining Producer Buy-in for Food Safety and Security in the United States
Authors: Osborne Dennis J. , Sanders Douglas C. , Ward Donn R. , Rushing James W.
Published: December 2018

This paper summarizes the management framework, organizing plan, and results of a multi-state, multi-institutional partnership delivering a targeted “train-the-trainer” program addressing food chain security in the southeastern U.S. The partnership provided good agricultural practices (GAPs) and good manufacturing practices (GMPs) –based training to fresh fruit and vegetable (produce) growers and packers throughout the region. Twelve southern states cooperated in this project: Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia. This 2000–04 work was funded by National Food Safety Initiative grants. Although proposed long before events of 11 Sept. 2001, the project and its results are increasingly relevant since that time. This is because consumer expectations regarding the nation's food supply now include a new security consciousness addressed in this project.
Fruit Analysis as an Indicator of the Iron Status of Nectarine and Kiwi Plant
Authors: Razeto Bruno , Valdés Graciela
Published: December 2018

Tissue analysis research for the diagnosis of iron (Fe) deficiency was carried out in nectarine (Prunus persica var. nucipersica) and kiwi (Actinidia deliciosa), two species susceptible to Fe deficiency. An experiment was performed during the 2003–04 growing season at Talagante County, Metropolitan Region, Chile, in 8-year-old `August Red' nectarine trees growing on a calcareous soil. Eighty midshoot leaves and 20 fruit per tree were collected from four randomly selected trees each with severe, moderate, or no symptoms of Fe deficiency on 7 Jan., 1 month before fruit harvest. Leaf color and chlorophyll varied among trees according to their severity of chlorosis, as did fruit pulp Fe but not leaf Fe. Fruit pulp Fe was highly correlated with fruit yield (R2 = 0.73), while leaf Fe was unrelated to yield. A second experiment was carried out in the 2004–05 growing season in two `Hayward' kiwi vineyards located in Chile. At each site, 10 mid-shoot leaves and eight fruit were collected on 15 Mar., 1 month before harvest from three plants either with or without Fe deficiency symptoms. As for nectarine, fruit pulp Fe and leaf color but not leaf Fe were indicators of plant chlorosis. Also, fruit pulp Fe was correlated with leaf color and fruit weight. Consequently, fruit pulp appears a promising tissue, probably better than leaf, for diagnosing the Fe status of nectarine and kiwi plants.
Establishment and Lateral Growth of Glyphosate-resistant Creeping Bentgrass in Bare Soil
Authors: Gardner D.S. , Nelson E.K. , Waldecker M.A. , Tarter W.R.
Published: December 2018

Plant establishment and lateral growth of glyphosate-resistant creeping bentgrass [Agrostis stolonifera (synonym A. palustris)] were assessed to determine if the insertion of the construct conferring herbicide tolerance affected establishment rate or aggressiveness characteristics in unmowed situations. Field studies were carried out in Michigan, Illinois, Ohio, and Oregon in 2000 and 2001 to examine the relative lateral growth of several transformed lines of creeping bentgrass, non-transformed controls, and cultivar standards. Vegetative plugs of creeping bentgrass were transplanted into replicated bare-soil plots and irrigated as needed to prevent moisture stress for an initial 6-week period. Measurements of maximum and minimum stolon spread, percent cover, and stand density for each entry were made in the field at all locations during 2000 and 2001. Few statistical differences (P = 0.05) in establishment and lateral growth were observed between individual lines of transgenic creeping bentgrass, non-transformed control lines, and standard cultivars and over a 15- to 18-month period. Overall, lateral growth and establishment rate of transgenic lines were similar to their non-transformed parent and the standard cultivars tested. Transgenic creeping bentgrass lines should have no greater potential for lateral growth than conventional creeping bentgrass cultivars currently in use.
The Effect of a Summer Garden Program on the Nutritional Knowledge, Attitudes, and Behaviors of Children
Authors: Koch S. , Waliczek T.M. , Zajicek J.M.
Published: December 2018

Fifty-six children were included in a study that evaluated the effectiveness of a garden program designed to teach health and nutrition to second through fifth grade-level children. The specific objectives of the research project were to evaluate the effect of the program on nutritional knowledge of the benefits of eating fruit and vegetables, nutritional attitudes toward fruit and vegetables, and eating behaviors of children, specifically consumption of fruit and vegetables. Children's nutritional knowledge was measured with an 11-question multiple-choice exam based on the educational activities performed. Children's nutritional attitudes regarding fruit and vegetables were measured with a fruit and vegetable preference questionnaire, and children's eating behaviors were evaluated with an interview question asking them what they ate for a snack that day. After participating in the nutritional program, children's knowledge about the benefits of eating fruit and vegetables significantly improved, but there were no significant differences found in participants' attitude scores toward fruit and vegetables. However, the participants did report eating healthier snacks after participation in the nutritional program.
Insect Management in Floriculture: How Important Is Sanitation in Avoiding Insect Problems?
Authors: Hogendorp Brian K. , Cloyd Raymond A.
Published: December 2018

Sanitation, which includes removing plant and growing medium debris, is an important component of any greenhouse or nursery pest management program. However, there is minimal quantitative information on how sanitation practices can reduce pest problems. In this study, conducted from May through Nov. 2005, we evaluated plant and growing medium debris as a source of insect pests from four greenhouses located in central Illinois. Two 32-gal refuse containers were placed in each greenhouse with a 3 × 5-inch yellow sticky card attached to the underside of each refuse container lid. Each week, yellow sticky cards and plastic refuse bags were collected from the containers and insects captured on the yellow sticky cards were identified. Insects captured on the yellow sticky cards were consistent across the four greenhouses with western flower thrips (Frankliniella occidentalis), fungus gnats (Bradysia spp.), and whiteflies (Bemisia spp.) the primary insects present each week. Insect numbers, in order of prevalence on the yellow sticky cards, varied across the four locations, which may be related to the type of plant debris discarded. For example, extremely high numbers of adult whiteflies (range = 702 to 1930) were captured on yellow sticky cards in one greenhouse each month from August through November. This was due to the presence of yellow sage (Lantana camera), bee balm (Monarda didyma), garden verbena (Verbena × hybrida), common zinnia (Zinnia elegans), sage (Salvia spp.) and fuchsia (Fuschia spp.) debris that was heavily-infested with the egg, nymph, pupa, and adult stages of whiteflies. High western flower thrips adult numbers in the greenhouses were generally associated with plant types such as marguerite daisy (Dendranthema frutescens) and pot marigold (Calendula officinalis) disposed while in bloom with opened yellow flowers, which contained adult western flower thrips. Based on the results of this study, it is important that greenhouse producers timely remove plant and growing medium debris from greenhouses or place debris into refuse containers with tight-sealing lids to prevent insect pests from escaping.
Hydrocooling as an Alternative to Forced-air Cooling for Maintaining Fresh-market Strawberry Quality
Authors: Ferreira Marcos D. , Brecht Jeffrey K. , Sargent Steven A. , Chandler Craig K.
Published: December 2018

Hydrocooling was evaluated as an alternative to forced-air cooling for strawberry (Fragaria × ananassa) fruit. `Sweet Charlie' strawberries were cooled by forced-air and hydrocooling to 4 °C and held in different storage regimes in three different trials. Quality attributes, including surface color, firmness, weight loss, soluble solids, and ascorbic acid content, pH and total titratable acidity, were evaluated at the full ripe stage. Fruit hydrocooled to 4 °C and stored at different temperatures for 8 or 15 days showed overall better quality than forced-air cooled fruit, with significant differences in epidermal color, weight loss, and incidence and severity of decay. Fruit stored wrapped in polyvinylchloride (PVC) film after forced-air cooling or hydrocooling retained better color, lost less weight, and retained greater firmness than fruit stored uncovered, but usually had increased decay. There is potential for using hydrocooling as a cooling method for strawberries.
Monitoring and Management of Pecan Orchard Irrigation: A Case Study
Authors: Kallestad Jeffery C. , Sammis Theodore W. , Mexal John G. , White John
Published: December 2018

Optimal pecan (Carya illinoiensis) production in the southwestern United States requires 1.9 to 2.5 m of irrigation per year depending on soil type. For many growers, scheduling flood irrigation is an inexact science. However, with more growers using computers in their businesses, and with soil moisture sensors and computerized data-collection devices becoming more inexpensive and accessible, there is potential to improve irrigation and water use efficiencies. In this project two low-cost soil monitoring instruments were introduced to a group of pecan producers. They were also given instruction on the use of Internet-based irrigation scheduling resources, and assistance in utilizing all of these tools to improve their irrigation scheduling and possibly yield. The objectives were to determine whether the technology would be adopted by the growers and to assess the performance of the sensors at the end of the season. Three out of the five growers in the project indicated they used either the granular matrix (GM) sensors or tensiometer to schedule irrigations, but compared to the climate-based irrigation scheduling model, all growers tended to irrigate later than the model's recommendation. Graphical analysis of time-series soil moisture content measured with the GM sensors showed a decrease in the rate of soil moisture extraction coincident with the model's recommended irrigation dates. These inflection points indicated the depletion of readily available soil moisture in the root zone. The findings support the accuracy of the climate-based model, and suggest that the model may be used to calibrate the sensors. Four of the five growers expressed interest in continued use of the tensiometer, but only one expressed a desire to use the GM sensor in the future. None of the participants expressed interest in using the climate-based irrigation scheduling model.
Landscape Performance, Flowering, and Seed Viability of 15 Japanese Silver Grass Cultivars Grown in Northern and Southern Florida
Authors: Wilson Sandra B. , Knox Gary W.
Published: December 2018

Japanese silver grass (Miscanthus sinensis) and 14 cultivars were transplanted in northern and southern Florida and evaluated for landscape performance, flowering, growth, and seed viability. All plants survived the 84-week study at both locations with the exception of `Morning Light', where 22% to 33% of the plants died. In northern and southern Florida, `Arabesque', `Adagio', `Cosmopolitan', and `Gracillimus' received the highest visual quality ratings on average throughout the entire study, yet other cultivars such as `Central Park' and `Silberfeder' performed well but had much narrower windows of peak performance. Cultivars such as `Little Kitten' and `Sarabande' performed far better in southern Florida than in northern Florida. Regardless of location, `Morning Light' and `Puenktchen' generally did not perform as well as other cultivars. In northern Florida, four consecutive months of very good to excellent flowering (75% to 100% canopy coverage) were observed for `Adagio', `Arabesque', `Cosmopolitan', `Gracillimus', `Little Kitten', `Sarabande', `Silberfeder', and `Zebrinus'. However, in southern Florida, peak flowering periods for these cultivars were delayed and generally only lasted for 1 to 2 months. On average, plants in northern Florida were larger and produced 2.8 times more flowers than plants in southern Florida. All cultivars produced viable seed with germination of viable seed ranging from 53.6% (`Cabaret') to 100% (`Gracillimus') in southern Florida, and from 49.8% (`Arabesque') to 100% (`Adagio', `Little Kitten', `Sarabande', and `Variegatus') in northern Florida.
Weed Control Potential and Crop Safety of Selected Herbicides in Field-grown Cannas
Authors: Wallace Russell W. , Hodges John C.
Published: December 2018

Herbicides were applied pre-emergence (PRE) and early post-directed (EP-DIR) to determine their effects on crop injury and control of palmer amaranth (Amaranthus palmeri) and nutsedge (Cyperus spp.) in field-grown cannas (Canna ×generalis). Results indicate that PRE-applied s-metolachlor + pendimethalin was the most effective treatment for controlling palmer amaranth. All other PRE-applied treatments failed to adequately control palmer amaranth. While moderate and temporary stunting was visible, in general, no herbicides (except trifloxysulfuron) significantly decreased canna rhizome yields. EP-DIR s-metolachlor or s-metolachlor + pendimethalin did not improve nutsedge control unless halosulfuron was included in the tank mixture. Addition of halosulfuron did not increase crop injury or decrease canna yields but did significantly reduce the number of nutsedge tubers found in the canna rhizomes at harvest. Results suggest that all PRE-applied herbicides tested were safe for cannas, but the lack of adequate palmer amaranth and nutsedge control prohibits their use as stand-alone herbicides for canna production in the midsouth. Post-directing applications of halosulfuron significantly improved nutsedge control and reduced tuber infestation and, therefore, should be included in all nutsedge management programs for canna rhizome production.
Comparing Student Performance in Live Versus Web-based Instruction in Herbaceous Plant Identification
Authors: Teolis Igino , Peffley Ellen B. , Wester David B.
Published: December 2018

A study was conducted to evaluate student performance after receiving the same horticultural lesson through one of two modes of instruction. Students enrolled in an introductory horticulture course received either a traditional herbaceous plant identification (ID) lesson with live plant specimens or the same lesson using only text and photographs on the Internet in one of their laboratory sessions. A follow-up experiment was conducted in which web-based students studied photographs of the exact same plants studied by students receiving traditional instruction. Learning style preferences and demographic information were obtained from surveys. For both experiments, students receiving traditional instruction had higher scores on the plant ID quiz than web-based students. All students were able to identify plants from photographs just as well as from live plant specimens. Visual learners scored higher when receiving traditional instruction when compared with web-based instruction. Student grade point average was positively correlated with quiz score for both experiments.
Taxonomy and Nomenclature of Baldcypress, Pondcypress, and Montezuma Cypress: One, Two, or Three Species?
Authors: Denny Geoffrey C. , Arnold Michael A.
Published: December 2018

As interest in issues such as seed source, provenance, genetic pollution, and threatened and endangered plant species grows, so does the need for an understanding of the relatedness and evolutionary history of plants. Appropriate taxonomy and nomenclature become much more important. Taxodium (L.) Rich. is a genus of landscape trees included in many plant materials courses across the country. It has been treated variously in the horticulture literature as having one, two, or three species. The most appropriate treatment is one species with three botanical varieties: baldcypress [Taxodium distichum (L.) Rich. var. distichum], pondcypress [T. distichum var. imbricarium (Nutt.) Croom], and montezuma cypress [T. distichum var. mexicanum Gordon].
Attitudes and Perceptions of Participants in a Horticulture Study Abroad Course at Iowa State University
Authors: VanDerZanden Ann Marie , Haynes Cynthia , Nonnecke Gail R. , Martin Robert
Published: December 2018

Globalization affects many aspects of American society, including higher education. Many institutions of higher education realize the need to help students become global citizens and thus require an international perspectives course as part of their undergraduate curriculum. The goal of this research was to evaluate the Horticulture Travel Course (Hort 496), which includes an international travel component, to determine whether it meets the university and College of Agriculture's expected learning outcomes and competencies in international and multicultural awareness. A 23-question survey instrument consisting of open- and close-ended questions was mailed to 116 former Hort 496 participants. Forty-three percent of the questionnaires were returned and were usable. Survey questions were designed to gather information on student demographics, previous international travel experience, learning outcomes achieved through participation in the pretrip preparatory class and the study abroad experience, and how these experiences influenced career development. Responses indicate that both the pretrip preparatory class and study abroad experience helped participants achieve the course learning outcomes. Furthermore, student presentations and guest speakers, and interacting with locals and planned tours immersed students the most in the pretrip preparatory class and study abroad experience, respectively. A majority of participants observed recognizable differences in agricultural management or production practices between the United States and the country visited. Participants also noted that Hort 496 had a positive affect on their communication skills, interpersonal skills, and personal growth.
Water Use and Fertilizer Response of Azalea Using Several No-leach Irrigation Methods
Authors: Million Jeff , Yeager Tom , Larsen Claudia
Published: December 2018

Although research has shown that plants grown with subirrigation systems such as ebb-and-flow and capillary mat require less water and fertilizer inputs than traditional overhead irrigation methods, similar information for capillary wick irrigation has not been available. We compared the growth and water use response of azalea (Rhododendron sp. ‘George Tabor’) grown in 6.5-inch-diameter “azalea” containers with three irrigation methods [overhead (OVR), subirrigation (SUB), and capillary wick (WCK)] and four fertilizer nitrogen (N) rates 0.5 to 2.0 lb/yard3 supplied by an incorporated, resin-coated, controlled-release fertilizer (Nutricote 17N–3.1P–6.7K, 180 d at 77 °F). OVR volume was adjusted to deliver 100% of evapotranspiration (ET) loss. For all irrigation treatments, the lowest N rate resulting in maximum plant growth was 1.0 lb/yard3, which was less than the label recommendation of 1.5 lb/yard3. At the N-limiting N rate of 0.5 lb/yard3, irrigation method had no effect (P < 0.05) on azalea growth. At N rates higher than 1.0 lb/yard3, decreased growth was observed for OVR compared with SUB and WCK. This negative effect on plant growth was attributed to salt injury as indicated by excessive pour-through electrical conductivity (EC) levels in OVR containers. At the end of the experiment, substrate EC was highest in the uppermost layer of SUB and WCK containers, reflecting the upward movement of water associated with these two irrigation methods. Water use efficiency, which ranged from 1.9 to 2.8 g shoot dry weight per liter of water lost through ET, was unaffected (P < 0.05) by irrigation method at the N rate of 1.0 lb/yard3. We concluded that the growth response of azalea to fertilizer N rate was similar for WCK and SUB despite periodic pour-through EC tests indicating higher substrate nutrient levels with WCK.
Growth and Yield of Vegetable Soybean (Edamame) in Mississippi
Authors: Zhang Lingxiao , Kyei-Boahen S
Published: December 2018

Soybean (Glycine max) grown as a vegetable is gaining in popularity in the U.S. and demand is expected to increase over the long term. However, information on production in the U.S. is limited because most of the product is imported. Field experiments were conducted at Stoneville, Miss., in 2004 and 2005 to evaluate the production and yield potential and to estimate the net returns for sustainable production in the Mississippi Delta. In 2004, four vegetable soybean varieties were evaluated and 23 varieties were evaluated in 2005. The varieties varied from maturity group III to VII. The late-maturing varieties were generally taller, had more nodes/plant, pods/plant, and fresh green pod yield at R6 stage (full seed) than the early-maturing varieties. Fresh green bean yield ranged from 1438 to 19,119 lb/acre in 2004. The mean bean yield for the 18 Apr. 2005 planting was 26,538 lb/acre compared with a mean of 18,131 lb/acre for the 10 May 2005 planting. Interaction occurred between planting date and variety as well as soil type and variety for all the variables evaluated. ‘Envy’ produced the lowest yield, whereas ‘Garden Soy 01’, ‘Garden Soy 21’, ‘Midori Giant’, ‘Mojo Green’, and ‘Moon Cake’ produced the highest fresh bean yield. The estimated net returns, using the Mississippi State Budget Generator as a guide, indicated more than twice the returns from growing the regular commodity soybean. The data suggest that vegetable soybean can fit well into the existing cropping system and could be a viable alternative crop for growers in the Mississippi Delta who want to capitalize on a niche market.
Connecticut Nursery and Landscape Industry Preferences for Solutions to the Sale and Use of Invasive Plants
Authors: Gagliardi James A. , Brand Mark H.
Published: December 2018

Survey data from 114 members (42% response rate) of the Connecticut Nursery and Landscape Association were analyzed to evaluate preferences for different potential solutions to reduce the annual sale of billions of dollars of invasive ornamental plants. The majority of respondents accurately identified key invasive plant characteristics, considered themselves to be knowledgeable about invasive plants, and cited trade journals and professional organizations as their sources of invasive plant information. Although industry members generally considered norway maple (Acer platanoides), japanese barberry (Berberis thunbergii), and winged euonymus (Euonymus alatus) to be invasive, only 14.5% and 8.1%, respectively, considered the emerging invasive species japanese silver grass (Miscanthus sinensis) and butterfly bush (Buddleja davidii) to be invasive. In comparing different approaches to reducing the sale of invasive ornamental plants, strong support was expressed for marketing noninvasive alternative plants (mean rank of 2.5) and for development of genetically altered sterile forms of invasive ornamentals (mean rank of 2.9; on a scale from 1 = most favorable to 6 = least favorable). Respondents strongly disfavored taxation as a method of reducing invasive plants sales (mean rank of 5.0) even if proceeds were directed toward invasive plant control and research. Plant bans (mean rank of 4.1) were also an unpopular choice for economically important crops, and respondents desired provisions for cultivars with reduced invasive risk to be included in plant bans. To foster maximum green industry participation in invasive plant control efforts, future directions should focus on creation of sterile forms of popular landscape plants, identification of consumer preference for noninvasive alternatives, and development of strong consumer education programs.
Salmonella Recovery from Tomato Fruit Surfaces as Affected by Ethylene
Authors: Mahovic Michael J. , Schneider Keith R. , Cordasco Kim , Brecht Jeffrey K.
Published: December 2018

The effect of ethylene on the survival of Salmonella cells residing on unwounded surfaces of tomato (Solanum lycopersicum) fruit was investigated in this study. Inoculated fruit were stored in flow-through chambers that were adjusted to maintain an environment simulating a tomato ripening room. Fruit were held at 20 °C and ≥95% relative humidity after surface inoculation with the low virulence and rifamycin-resistant pathogen S. enterica ssp. enterica serovar Typhimurium strain LT2 (S. Typhimurium). Tomato fruit were treated either with a continuous flow (rate, ≈200 mL·min−1) of air or with ≥150 μL·L−1 ethylene in air. Bacterial recovery at 0, 24, 48, and 72 h after initiation of treatment showed that total populations of the S. Typhimurium cells declined in both the air and ethylene treatments during the first 24 to 48 h of storage, then increased to near initial levels by 72 h, similar to decline and recovery reported by other researchers in nonethylene treatment trials. These results suggest that although Salmonella can survive on the surfaces of tomato fruit in typical ripening rooms, proliferation of Salmonella is neither promoted nor inhibited by ethylene exposure.
Postharvest Quality and Acceptance of LB8-9 Mandarin as a New Fresh Fruit Cultivar
Authors: Dou Huating , Gmitter Fred G.
Published: December 2018

A new mandarin cultivar currently designated as selection LB8-9 [‘Clementine’ mandarin (Citrus reticulata) × ‘Minneola’ tangelo, Duncan grapefruit (Citrus paradisi) × Dancy tangerine (C. reticulata)], soon to be released by the University of Florida, Citrus Research and Education Center, Lake Alfred, has been evaluated for postharvest fruit quality and consumer acceptance. Comparisons were made with ‘Sunburst’ and ‘Minneola’ mandarins, which overlap the early and late LB8-9 maturity season, respectively. LB8-9 and ‘Sunburst’ fruit stored 2 weeks at 70 °F developed similar decay percentages (35% to 37%), while ‘Minneola’ showed only 16% decay. Postharvest pitting incidence was zero in LB8-9 and ‘Minneola’ and 3% in ‘Sunburst’ stored at 70 °F and 92% to 96% relative humidity (RH). At the same storage conditions, LB8-9 and ‘Sunburst’ developed better fruit peel color (hue = 60) in comparison with the ‘Minneola’ (hue = 65) mandarin. No differences were found in fruit external peel color (hue angle), chilling injury, or decay among three cultivars stored at 40 °F after 6 weeks. However, juice color was the best in ‘Sunburst’ as indicated by the highest color numbers (44), followed by LB8-9 (40) and ‘Minneola’ (38). Wax-formulation studies indicated that carnauba wax was the best formulation for coating LB8-9 because of low decay incidence, weight loss, and good color. No difference was found in fruit taste panels at day 6 after packing, while a better score of acceptance in the fruit taste panel was recorded for LB8-9 than ‘Minneola’ after 50 d of storage at 40 °F and 92% to 96% RH. LB8-9 fruit had a higher soluble solids concentration [SSC (14.0)] and acid (1.12) than ‘Minneola’ or ‘Sunburst’ mandarins, both having a SSC and acid lower than 11.5 and 0.86, respectively. Sucrose concentration was noticeably higher in the new cultivar (7.14 g/100 mL) than in ‘Minneola’ (5.27 g/100 mL) or ‘Sunburst’ (6.10 g/100 mL). Vitamin C concentration was 42.43 mg/100 mL for the new cultivar, which was considerably higher than ‘Minneola’ (23.27 mg/100 mL) or ‘Sunburst’ (26.25 mg/100 mL). Overall, LB8-9 has good potential as a new fresh fruit for the consumer, and no serious problems were noted with typical postharvest handling.
Landscape Architects' Use of Native Plants in the Southeastern United States
Authors: Brzuszek Robert F. , Harkess Richard L. , Mulley Susan J.
Published: December 2018

In their efforts to provide better land stewardship and management, landscape architects are increasingly addressing site ecology in a wide variety of project types. From urban developments to rural properties, designers are using more sustainable design and management techniques, which include the expanded use of regional native plants. This survey study explores the use of native plants by landscape architects in the southeastern United States. Survey results show that southeastern United States designers are using a significant proportion of regional native plant species in their project specifications. Rather than using native plants strictly for conservation measures, landscape architects have found local species to be better suited to difficult or unique site conditions. The findings show that there is potential for expansion in the production and marketing of plant species indigenous to the southeastern United States.
Sweet Corn Nutrient Uptake and Removal
Authors: Heckman J.R.
Published: December 2018

Current emphasis on writing comprehensive nutrient management plans for crop production in the mid-Atlantic region of the United States requires accurate crop nutrient removal values for vegetable crops. Therefore, studies were conducted to measure nutrient uptake in harvested fresh sweet corn (Zea mays) ears in 2003 on a sandy loam soil and in 2004 on a silt loam soil, in New Jersey. Nine varieties were included in the study to represent early, mid-, and late-season hybrids. Corn production practices followed local extension recommendations. The crop was seeded by hand and thinned to ensure a uniform within-row spacing of 9 inches and a population of 23,231 plants/acre. Nutrient concentrations were determined on ear and stover samples oven-dried at 70 °C for 72 hours. Mean nutrient uptake values for full-season varieties based on a typical sweet corn yield of 150 cwt/acre (about 18,396 ears/acre) would be projected to remove (in lb/acre) 51 N, 9.1 P, 34 K, 3.7 S, 2.0 Ca, 3.9 Mg, 0.024 B, 0.09 Fe, 0.044 Mn, 0.014 Cu, and 0.072 Zn. Values for N, P, and K are similar to reference values in Knott's Handbook for Vegetable Growers (4th ed.). Due to smaller ear size, nutrient removal values were generally lower for early and mid-season varieties. In 2004 only, nutrient removal by harvesting the crop residue was also determined by assuming a harvest of 23,231 plants/acre, minus the upper ear for the average full-season hybrid. This biomass was found to remove (in lb/acre) 126 N, 13.4 P, 173 K, 11.6 S, 20.6 Ca, 13.6 Mg, 0.05 B, 0.37 Fe, 0.30 Mn, 0.05 Cu, and 0.13 Zn.