bluuebunny/crossref_metadata_2025 huggingface dataset:
Harvest Maturity and Storage Affect Quality of `Cripps Pink' (Pink Lady®) Apples
Authors: Drake S.R. , Elfving D.C. , Eisele T.A.
Published: December 2018

Quality of `Cripps Pink' apples (Malu × domestica) harvested at a starch index of 2 and 4 was evaluated over three crop seasons. Apple quality was evaluated after harvest and after regular atmosphere (RA) and controlled-atmosphere (CA) storage at 1% O2 and 1% CO2, 1% O2 and 3% CO2, and 1% O2 and 5% CO2 (1 year only) at 1 ºC (33 to 34 ºF). Over three seasons, commercially acceptable fruit quality was achieved on either harvest date following both long-term RA and CA storage. Fruit size was not different between apples harvested at a starch index of 2 or 4. Firmness and acids remained at acceptable levels [62 N (14 lb) and ≥0.50%, respectively] in `Cripps Pink' apples regardless of maturity, storage time or storage conditions. Delaying harvest after a starch index of 2 was achieved increased soluble solids concentration (SSC), SSC to TA (titratable acidity) ratio, peel color, malic acid and citric acid concentrations but decreased fructose content. `Cripps Pink' apples responded well to CA storage conditions of 1% O2 with 1% or 3% CO2, but displayed significant firmness loss and greatly increased internal breakdown at 1% O2 and 5% CO2 at 1 ºC.
The Master Gardener Program: Do Benefits of the Program Go Beyond Improving the Horticultural Knowledge of the Participants?
Authors: Waliczek T.M. , Boyer Roxanne , Zajicek J.M.
Published: December 2018

Texas Master Gardeners participating in an Annual Master Gardener Advanced Training Conference held in College Station, Texas, in June 2000 were asked to complete a survey investigating the impact of the Master Gardener program on perceptions of quality of life and motivations for becoming a Master Gardener. A retrospective pretest/posttest was used to compare the gardeners' current perceptions and their perceptions prior to becoming a Master Gardener. After becoming Master Gardeners, participants reported statistically significant improvements in areas relating to quality of life including physical activity, social activity, self-esteem, and nutrition. Comparisons between demographic characteristics and perceived quality of life scores showed no significant differences. Reasons associated with gaining horticultural information were the primary motivations for becoming a Master Gardener.
Generating Private-Sector Funding for Extension Programs
Authors: Hochmuth George J. , Maynard Donald N.
Published: December 2018

Delivery of modern extension programs involves considerable expenses that are becoming scarce from traditional sources. Successful extension educational programs will need to find additional revenue sources to fund educational materials, speaker costs, conferences, and other needs. It is important to become as financially efficient as possible and sometimes this means consolidating some programs and eliminating others. Charging fees to attendees is one means of covering costs of delivering programs. The University of Florida is partnering with the agriculture industry and trade journal publishers to provide resources and publishing for educational programs and materials.
A Survey of Professional Turfgrass Managers in Southern California Concerning Their Use of Turfgrass Best Management Practices
Authors: Klein Grant J. , Green Robert L.
Published: December 2018

Turfgrass management best management practices (BMPs) encompass a wide variety of activities, including fertilization, irrigation, mowing, pest control, and soil management. Little attention is given to determining just how effective information regarding BMPs is being assimilated and used by professional turfgrass managers. The objectives of this study were to assess the current perception and implementation of selected turfgrass BMPs and to determine whether or not those perceptions and implementations differed 1) between turfgrass advisors and managers and 2) between general and sports turfgrass managers. Professionals from the turfgrass industry, with an average of 13 years of experience and largely comprised of decision-makers (88%), were surveyed at the University of California, Riverside, Turfgrass Research Conference and Field Day in Fall 1998 and 1999. Turfgrass managers, especially sports turfgrass managers, were found to be the most committed to implementing the BMPs in the survey. Overall, survey respondents considered BMPs to be important and not highly difficult to implement. Limitations to the adoption of BMPs were a lack of financial backing, employee education, and necessary time—all of which could be remedied with a sufficient commitment of resources by the turfgrass industry.
Demographics and Volunteer Experiences of Oregon Master Gardeners
Authors: Kirsch Erika , VanDerZanden Ann Marie
Published: December 2018

The last statewide survey of the Oregon Master Gardener (MG) Program was completed in 1992. Since that time, the program has expanded from 20 to 27 counties and increased by over 600 new volunteers. Compared to other MG programs around the United States, Oregon is the tenth largest in number of volunteers and seventh in hours volunteered. Considering the size of the Oregon MG program and changes seen in annually compiled statistics, a better understanding of who the Oregon MGs are and what they think about their personal volunteer experience became critical. We developed a survey tool to understand the Oregon MG demographic composition and personal volunteer experience. Compared to the 1992 baseline survey, the general trends found in the 2001 survey suggest that Oregon MGs are younger, joining the program with more college education, live further from cities and towns, and are more often employed. Still, the commitment level to volunteering is similar to, or has exceeded 1992 levels.
Transition from Conventional to Organic Farming Systems: I. Challenges, Recommendations, and Guidelines for Pest Management
Authors: Zinati Gladis M.
Published: December 2018

Conventional agricultural systems increase per-area food production, but deplete natural resources and degrade both crop and environmental quality. Many of these concerns are addressed by sustainable agricultural systems, integrated pest management, biocontrol, and other alternative systems. Environmental and social concerns have escalated the need for alternative agricultural systems in the last decade. One alternative, the organic farming system, substitutes cultural and biological inputs for synthetically made fertilizers and chemicals for crop nutrition and pest management. Practices used for crop and pest management are similar during transition from conventional to organic farming systems, but produce is not certified to be organic during the transition period. During the transition from conventional to organic farming, growers may face pest control difficulties and lower yields when conventional practices are abandoned. The objectives of this paper are to 1) give an overview of the reasons for converting to organic farming and the challenges that growers face during the transition period, 2) outline some potential strategies for crop, soil, and pest management, and 3) list guidelines and recommendations for pest management during the transition to organic farming. Implementation of crop and pest management practices depends on geographical location, climate, available onsite resources, and history of the land. During transition, growers rely on cultural mechanisms and on organic and mineral sources to improve soil fertility, to build a population of natural enemies to suppress pest populations. Pest management practices during the transition period that reduce pest populations to economically manageable levels include crop rotation, cultivation, cover crops, mulches, crop diversification, resistant varieties, and insect traps. These practices also enrich the soil biota and increase crop yields before produce is certified organically grown.
Current Pest Management Systems for Pecan
Authors: Reid William
Published: December 2018

Pecans (Carya illinoinensis) are produced under a wide array of environmental conditions—from the warm humid southeastern states, to the continental climate of the central plains, to the arid climates of the American west. In addition, pecan cultural systems vary from the low-input management of native stands of seedling trees to the intensive management of single-cultivar pecan orchards. This wide diversity of pecan agroecosystems has fostered the development of innovative, site-specific approaches toward pecan pest management. Current pecan pest management programs require an intimate knowledge of orchard ecology. Growers use monitoring methods and prediction models to track pest populations. Biological control agents are conserved by habitat manipulation and/or augmented through inoculative releases. Selective pesticides are used to control target pests while conserving natural enemies. Four pecan cultural systems are described in detail to illustrate how ecological principles are applied to widely diverse pecan agroecosystems.
Genetic Improvement of Virginia Pine Planting Stock for Christmas Tree Production in South Carolina
Authors: Knoth Jenny , Frampton John , Moody Ray
Published: December 2018

Twenty open-pollinated families from a virginia pine (Pinus virginiana) seed orchard in South Carolina were planted and managed as Christmas trees at three sites. Retail value and related traits were assessed once the tests reached marketable size (4 years in the field). All traits assessed (except survival) proved to 1) be under a moderate degree of genetic control (family mean heritability = 0.68 for retail value) and 2) have a large range among open-pollinated family means ($11.42/tree to $22.00/tree, retail value) suggesting that they will response well to the traditional tree improvement approach of selection, breeding and testing. The retail value of the best five families tested averaged an increase of $3.47/tree or 20.7% more than the average. At a 6 × 6 ft (1.8 m) spacing [1,210 trees/acre (2,990 trees/ha)], these families would produce an increase in revenue of almost $4,200/acre ($10,387/ha). Much of this increase in value is a result of reducing the cull rate from 14.5% to 8.1%. Survival, height, crown density and straightness of these five families also exceeded the average of the 20 families tested.
Water Table Depth Effect on Water Use and Tuber Yield for Subirrigated Caladium Production
Authors: Stanley C.D. , Harbaugh B.K.
Published: December 2018

A study was conducted to determine the effect of water table depth on water use and tuber yields for subirrigated caladium (Caladium × hortulanum) production. A field-situated drainage lysimeter system was used to control water table depths at 30, 45 and 60 cm (11.8, 17.7, and 23.6 inches). Water use was estimated by accounting for water added or removed (after rain events) to maintain the desired water table depth treatments. In 1998, tuber weights, the number of Jumbo grade tubers, and the production index (tuber value index) of `White Christmas' were greater when plants were grown with the water table maintained at 30 or 45 cm compared to 60 cm. In 1999, tuber weights, the number of Mammoth grade tubers, and the production index, also were greater when plants were grown at water table depths of 30 or 45 cm compared to 60 cm. The average estimated daily water use was 6.6, 5.1, and 3.3 mm (0.26, 0.20, and 0.13 inch) for plants grown at water table depths of 30, 45, and 60 cm, respectively, indicating an inverse relationship with water table depth. While current water management practices in the caladium industry attempt to maintain a 60-cm water table, results from this study indicate that, for subirrigated caladium tuber production, the water table should be maintained in at 30 to 45 cm for maximum production on an organic soil.
Indicators of Maturity and Storage Quality of `Lapins' Sweet Cherry
Authors: Drake S.R. , Elfving D.C.
Published: December 2018

Three commercial `Lapins' sweet cherry (Prunus avium) orchards were used for this study during three crop seasons. Orchards were selected based on the historical average date of commercial harvest. The difference in commercial harvest date among the three orchards was 5 to 7 days. Three harvests were carried out in each orchard each year: 1) beginning 4 to 5 days before commercial harvest, 2) at commercial harvest, and 3) 4 to 5 days after commercial harvest. Fruit quality was determined after 0, 7, 14, and 21 days of storage. Harvesting fruit up to 5 days later than normal commercial harvest resulted in increases in fruit weight and soluble solids content along with no loss of firmness or change in acidity. Pedicel color did not change as harvest was delayed. Changes in visual ratings of both fruit and pedicel appearance with delayed harvest were detectable in only 1 of 3 years. Neither pitting nor bruising was influenced by harvest date. The amount of pitting or bruising present was related more to the year of harvest than to harvest date. Delaying harvest a short time beyond the normal commercial harvest date could enhance consumer appeal and increase fruit value. Storage time after harvest resulted in reduced fruit and pedicel appearance, but only beyond 14 days of storage.
Effects of Variable Shading in a Greenhouse Study on Rhizome Weight, Root Length, and Bud Proliferation in Goldenseal
Authors: Quigley Martin F. , Mulhall Stephen
Published: December 2018

Goldenseal (Hydrastis canadensis) is an herbaceous perennial valued for its fleshy rhizomes, which contain the alkaloids hydrastine and berberine. While it is understood that relative shade influences growth and yield of goldenseal, optimal shade level for maximum rhizome mass and plant vigor under cultivation has not been established. Goldenseal plants grown from cold stratified rhizomes were kept under shade for 5 months in the greenhouse. Treatments were five different shade levels ranging from 60% to 95% of full shade, plus a control group in full sun. Measured variables included rootlet length, bud development, and rhizome mass. Plants grown under moderate shade (60 to 70%) produced longer and more numerous rootlets, more bud primordia, and had greater rhizome mass and healthier leaves than plants grown under extreme shade (95%) or in full sun. Decreasing shade density had a major impact on plant condition and growth. Those plants grown with the greatest sun exposure displayed 100% scorch damage to the foliage, in comparison to <35% damage in the moderate shade (30 to 40%). The results suggest that moderate shading may double yield in rhizome mass, and promote increased bud proliferation in subsequent seasons. Late season leaf vigor is not correlated with rhizome mass.
Survey of Container Nursery Irrigation Practices in Georgia
Authors: Garber M.P. , Ruter J. M. , Midcap J.T. , Bondari K.
Published: December 2018

A 2001 survey of 102 nurseries that were members of the Georgia Green Industry Association was conducted to assess irrigation practices of container ornamental nurseries. Mean nursery size was 64 acres (26 ha) and mean annual revenue was about $3 million. About 50% of the irrigation water was from wells and the other 50% came from surface sources, such as collection basins. Irrigation in smaller containers, including #1, #3, and #5, was applied primarily by overhead methods, while larger containers (#7, #15, #25) made extensive use of direct application methods, such as drip or spray stakes. Frequency of irrigation in the summer growing months was about three times that of the winter season. Georgia nurseries use irrigation practices suggested in Southern Nursery Association best management practices, including collection of runoff water (48%), cyclic irrigation (44%), watering in the morning (92%), and grass strips between the production beds and drainage areas (60%).
Influence of Short-term Cyclic Cold Temperature Stress on Muskmelon and Honeydew Yield
Authors: Korkmaz Ahmet , Dufault Robert J.
Published: December 2018

Muskmelon (Cucumis melo) seedlings are transplanted in late winter or early spring before last frost date to ensure early yields; however, this makes them very vulnerable to temperatures cycling between almost freezing and optimal temperatures. To simulate temperature alternations that may occur after field transplanting, `Athena', `Sugar Bowl', `Eclipse' muskmelon, and `Tesorro Dulce' honeydew (C. melo) transplants were subjected to 2 ± 1 °C (35.6 ± 1.8 °F) in a walk-in cooler and then to 29 ± 5 °C (84.2 ± 9.0 °F) in a greenhouse before field planting. In 1998, transplants were exposed to 2 °C for 9 to 54 hours, and for 9 to 81 hours in 1999. `Athena' and `Sugar Bowl' yielded less early melons in both years, whereas `Eclipse' and `Tesoro Dulce' early yields were only reduced in 1999. Total yields of `Athena' decreased linearly in both years with 10% yield reduction occurring with 12 to 21 hours of cold stress. Total yields of `Sugar Bowl' decreased linearly in both years with 11 to 18 hours of cold stress causing 10% yield reduction in 1998 and 1999, respectively. Therefore, early planting before last frosts of all these muskmelon and honeydew cultivars should be done with caution since reductions in early yields are highly probable.
Efficacy of Plantpro 45 as a Seed and Soil Treatment for Managing Fusarium Wilt of Basil
Authors: Adams Pamela D. , Kokalis-Burelle Nancy , Basinger William H.
Published: December 2018

Plantpro 45, an iodine-based compound, was evaluated as a seed treatment for management of fusarium wilt caused by Fusarium oxysporum f.sp. basilici on basil (Ocimum basilicum) in greenhouse assays and for effects on growth of the pathogen in vitro. Plantpro 45 at a concentration of 300 mg·L-1 (ppm) prevented fusarium hyphal growth in vitro. Seed treatments of 800 to 1000 mg·L-1 eliminated fungal contamination of seed and increased germination by 27% compared to the nontreated control. Basil transplants grown from seed treated with 400, 800, and 1000 mg·L-1 were significantly taller, weighed more, exhibited larger leaf area, and had reduced wilt severity in the greenhouse compared to the nontreated control. Transplants grown in soil treated with increasing concentrations of Plantro 45 had correspondingly decreased wilt severity, regardless of whether or not the seeds had been previously treated with Plantpro 45. Further research and optimization of soil and foliar applications in combination with seed treatments are needed to provide a complete program for management of fusarium wilt of basil.
Reducing Weeds in Ornamental Groundcovers under Shade Trees through Mixed Species Installation
Authors: Quigley Martin F.
Published: December 2018

Six durable but slow-to-establish groundcover species, and three fast-growing but short-lived groundcover species, were planted singly and in paired combinations under mature landscape trees to test for relative weed suppression. Installations were replicated on an urban site and a rural site, monitored for two growing seasons, and weeded periodically by hand. All weeds were dried and weighed, and subplot averages (160 observations) for each plant combination were tested by analysis of variance. Weeds were significantly fewer and smaller in the mixed species than in single species subplots. Weed biomass was also significantly less in monospecific groundcover subplots than in unplanted control plots. These results suggest that reduced maintenance cost (and input) for weed control, along with better initial coverage appeal of the paired plantings, may increase marketability of perennial groundcovers.
An Attempt to Improve Uniformity of a Gaspardo Precision Seeder
Authors: Parish R.L. , Bracy R.P.
Published: December 2018

Prior studies have demonstrated that a Gaspardo vacuum seeder provides less uniform seed spacing than a Stanhay belt seeder. It was hypothesized that the difference was primarily because of the greater seed drop height on the Gaspardo seeder. A Gaspardo metering unit was modified by adding a slide or an enclosed tube to guide the seeds from the release point (seed plate) to 1.0 inch (25 mm) above the bottom of the seed furrow. Seed uniformity tests were conducted with cabbage (Brassica oleracea), onion (Allium cepa), and mustard (Brassica juncea) seeds. The modified planter unit was compared with an unmodified unit. No improvement in seeding uniformity was noted with either the slide or the tube. In fact, seed placement uniformity was degraded with the addition of the slide and tube. Although it is probable that the seed spacing nonuniformity was caused by drop height, attempts to control the seed trajectory were unsuccessful.
Rooting Foliage Plant Cuttings in Compost-formulated Substrates
Authors: Chen Jianjun , McConnell Dennis B. , Robinson Cynthia A. , Caldwell Russell D. , Huang Yingfeng
Published: December 2018

Three composts, derived from municipal solid waste with biosolids, yard trimmings, and yard trimmings with biosolids, were mixed by volume with sphagnum peat and pine bark to formulate 12 substrates. After characterizing physical and chemical properties, the substrates, along with a control, were used for rooting single eye cuttings of pothos (Epipremnum aureum) and terminal cuttings of maranta (Maranta leuconeura) and schefflera (Schefflera arboricola) in enclosed polyethylene tents. All cuttings initiated roots with no significant difference in root numbers per cutting 14 days after sticking, but root lengths 21 days and root-ball coverage ratings 45 days after sticking were significantly affected by substrates. Five of 12 compost-formulated substrates resulted in root lengths of cuttings equal to or longer than the control. In addition to desirable physical properties such as bulk density, total porosity, and air space, common chemical characteristics of the five substrates included low concentration of mineral elements, initial electrical conductivity ≤3.0 dS·m-1 based on the pour through extraction method, and pH between 3.8 to 5.0. The five substrates were formulated by combining composted municipal solid waste with biosolids or yard trimmings with biosolids volumetrically at 20% or less or composted yard trimmings at 50% or less with equal volumes of sphagnum peat and pine bark.
Penetration and Sorption of Methyl Bromide in Returnable Plastic Containers
Authors: Boersig Michael R. , Hartsell Preston , Smilanick Joseph
Published: December 2018

Methyl bromide (MB) penetration rates, sorption levels, and concentration.time (CT) products were compared in returnable plastic containers (RPCs) and corrugated grape boxes (CGBs). During a 2.5-hour fumigation, sorption of methyl bromide in RPCs and CGBs was 9.8% and 18.1%, respectively. The lower sorption in RPCs increased the exposure of grapes (Vitis vinifera) to MB. Equilibrium concentrations of MB (concentrations that had stabilized) in RPCs and CGBs were 68.2 and 59.2 g·m-3 (4.26 and 3.70 lb/1000 ft3) respectively. The CT products in RPCs and CGBs were 170.5 and 147.6 g·h-1·m-3 (10.66 and 9.19 lb/h/1000 ft3), respectively, and far below phytotoxic concentrations according to the U.S. Department of Agriculture schedule.
Pesticide Spraying in Indian River Grapefruit: II. Overview of Factors Influencing Spray Efficacy and Off-target Deposition
Authors: Stover Ed , Scotto Dominick , Wilson Chris , Salyani Masoud
Published: December 2018

Foliar application of spray materials is an integral component of commercial citrus production. An intensive assessment of spray application practices has been stimulated by low fruit value and increased concern about potential surface water contamination in the Indian River citrus region of Florida. Many publications report research results regarding distribution of spray materials within orchards and off-target deposition, but interpretation is challenging because so many factors influence spray results, and integrating this information into practical recommendations is difficult. Canopy geometry and density are prominent factors contributing to variable deposition and spray drift. Environmental factors such as temperature, relative humidity, wind speed, and wind direction also greatly influence spray deposition and drift, and substantial changes can occur within seconds. In addition the physical and/or mechanical set up of the sprayer interact significantly with the other factors. A better understanding of these interactions should help growers optimize spray effectiveness and efficiency while reducing potential off-target effects.
Effectiveness of Web-based versus Live Plant Identification Tests
Authors: Anderson N.O. , Walker J.D.
Published: December 2018

Setup and administration of comprehensive live plant identification (ID) tests in horticulture classes is time-consuming and costly. The curricular goal of this study was to integrate Web-based plant ID self-tests and computer-graded tests into floriculture potted plant production classes to potentially replace live plant ID tests. This research was conducted during 2000 and 2001 with students enrolled in Hort 4051 at the University of Minnesota, St. Paul. All plant ID tests were mandatory, constituting 12% of the grade. In 2000, only Web-based ID tests were used, while both Web-based and live plant ID tests were used in 2001. Two separate self-tests were designed as study aids with 34 randomized photographs/test. Correct spelling was mandatory to receive full credit for genus, species, and family. Self-tests could be taken ten times each per student. Students then completed two for-credit (graded), unmonitored Web-based tests. Students completed a Website evaluation form at the end of the semester. The two live plant ID tests were conducted with the same materials and were monitored. Mean student scores for the Web-based ID tests in 2000 ranged from 73.5 to 99.5% with a class average of 91.9%; there were no significant differencesamong students' scores. Student Web-based ID test scores for 2001 had a similar range with a high class average of 93.8%. In contrast, the 2001 live plant ID tests had a wider score range of 21.7% to 100.0% and lower class average (72.2%). Web-based and live plant ID tests, students, and their interaction were all highly significant. Web site course evaluations demonstrated interesting trends in student perception of Web-based and live plant testing. The implications for future class use and potential modifications for continued Web-based instruction are presented.
Postharvest Handling and Storage of Fresh Cranberries
Authors: Forney Charles F.
Published: December 2018

High-quality cranberry (Vaccinium macrocarpon) fruit are required to fulfil the growing markets for fresh fruit. Storage losses of fresh cranberries are primarily the result of decay and physiological breakdown. Maximizing quality and storage life of fresh cranberries starts in the field with good cultural practices. Proper fertility, pest management, pruning, and sanitation all contribute to the quality and longevity of the fruit. Mechanical damage in the form of bruising must be minimized during harvesting and postharvest handling, including storage, grading, and packaging. In addition, water-harvested fruit should be removed promptly from the bog water. Following harvest, fruit should be cooled quickly to an optimum storage temperature of between 2 and 5 °C (35.6 and 41.0 °F). The development of improved handling, refined storage conditions, and new postharvest treatments hold promise to extend the storage life of fresh cranberries.
Correcting Iron Deficiency in Calibrachoa Grown in a Container Medium at High pH
Authors: Fisher Paul R. , Wik Ron M. , Smith Brandon R. , Pasian Claudio C. , Kmetz-González Monica , Argo William R.
Published: December 2018

The objective was to evaluate and compare foliar spray and soil drench application methods of iron (Fe) for correcting Fe deficiency in hybrid calibrachoa (Calibrachoa × hybrida) grown in a container medium at pH 6.9 to 7.4. Untreated plants showed severe chlorosis and necrosis, stunting, and lack of flowering. An organosilicone surfactant applied at 1.25 mL·L-1 (0.160 fl oz/gal) increased uptake of Fe from foliar applications of both ferrous sulfate (FeSO4) and ferric ethylenediamine tetraacetic acid (Fe-EDTA). Foliar sprays at 60 mg·L-1 (ppm) Fe were more effective when Fe was applied as Fe-EDTA than FeSO4. Increasing Fe concentration of foliar sprays up to 240 mg·L-1 Fe from Fe-EDTA or 368 mg·L-1 Fe (the highest concentrations tested) from ferric diethylenetriamine pentaacetic acid (Fe-DTPA) increased chlorophyll content compared with lower spray concentrations, but leaf necrosis at the highest concentrations may have been caused by phytotoxicity. Drenches with ferric ethylenediaminedi(o-hydroxyphenylacetic) acid (Fe-EDDHA) at 20 to 80 mg·L-1 Fe were highly effective at correcting Fe-deficiency symptoms, and had superior effects on plant growth compared with drenches of Fe-DTPA at 80 mg·L-1 Fe or foliar sprays. Efficacy of Fe-DTPA drenches increased as concentration increased from 20 to 80 mg·L-1 Fe. An Fe-EDDHA drench at 20 to 80 mg·L-1 Fe was a cost-effective option for correcting severe Fe deficiency at high medium pH.
Yields and Economics of High Tunnels for Production of Warm-season Vegetable Crops
Authors: Waterer Doug
Published: December 2018

Crop development rates, yields and production economics for muskmelon (Cucumis melo), pepper (Capsicum annuum) and tomato (Lycopersicon lycopersicum) grown in high tunnels [4.3 m wid × 2.5 m high × 29 m long (14 × 8 × 96 ft)] were compared to standard low tunnels over several cropping seasons in a temperate production area. The polyethylene-covered high tunnels protect several rows of crop for the duration of the cropping season. Air temperatures in the high tunnels were controlled by raising the sides of the tunnel. Low tunnels cover only a single row and must be removed soon after the crop is established to prevent overcrowding or overheating. When the low tunnels were in place, rates of accumulation of growing-degree days (GDDs) and early crop growth were comparable in the two tunnel systems. However, once the low tunnels were removed, the accumulation of GDDs in the high tunnels exceeded the standard system. The crops in the high tunnels matured 1 to 2 weeks earlier and produced substantially greater fruit yields before frost than in the low tunnel treatments. The high tunnels provided little frost protection and were of limited utility for extension of the growing season. The high tunnels were much more costly to purchase and construct than the low tunnels but were durable enough to be used for multiple cropping seasons. Based on wholesale commodity prices, it would take 2 to 5 years for the enhanced gross returns obtained with the high tunnels to cover their higher capital costs.
Pawpaw Variety Development: A History and Future Prospects
Authors: Peterson R. Neal
Published: December 2018

The pawpaw (Asimina triloba) is a new crop in the early stages of domestication. Recently commercialization has become feasible with the availability of high quality varieties. The history of pawpaw varieties is divided into three periods: 1900-50, 1950-85, and 1985 to the present. The history before 1985 was concerned primarily with the discovery of superior selections from the wild but experienced a serious break in continuity around 1950. The third period has been characterized by greater developmental activity. Larger breeding programs have been pursued, regional variety trials initiated, a germplasm repository established, and a formal research program at Kentucky State University (KSU) instituted. Future breeding will likely rely on dedicated amateurs with the education and means to conduct a 20-year project involving the evaluation of hundreds of trees. For the foreseeable future, governments and universities will not engage in long-term pawpaw breeding.
Selection Preferences for Crabapple Cultivars and Species
Authors: Romer James P. , Iles Jeffery K. , Haynes Cynthia L.
Published: December 2018

Crabapples (Malus spp.) are commonly planted ornamental trees in public and private landscapes. Hundreds of selections are available that represent a wide range of growth habits, ornamental traits, and varying degrees of resistance/susceptibility to disease. We distributed 1810 questionnaires in 13 states (Oregon, Washington, Utah, Colorado, Minnesota, Iowa, Missouri, Illinois, Indiana, Michigan, Ohio, New York, and Pennsylvania) to members of either nursery and landscape associations or the Associated Landscape Contractors of America (ACLA, Herndon, Va.) to identify crabapple preferences across a broad geographic region of the United States. We also were interested in learning if regional disease problems were important to green-industry professionals as they decide which crabapples to include in their inventories. Our respondent population numbered 511 (28.2% response rate). A large percentage of respondents (79.4%) said their retail clients focused mostly on fl ower color when choosing crabapples for the home landscape, while commercial clients showed slightly more interest in growth habit (32.5%) than fl ower color (28.7%). `Prairifire' was identified by respondents in all regions, except the west-central (Colorado and Utah), as the crabapple most frequently recommended to clients when tree size is not important. Respondents in the west-central region most often (48.7%) recommend the fruitless selection `Spring Snow'. Respondents in all regions, except the west-central, identified apple scab (Venturia inaequalis) as the most prevalent crabapple disease and named scab-susceptible `Radiant' as the selection most frequently discontinued.
Computer and Internet Use Among Oregon Master Gardeners
Authors: VanDerZanden Ann Marie , Kirsch Erika
Published: December 2018

The Internet has become a tool used in business, education, and leisure pursuits. Extension has used the Internet in a variety of ways including the training of extension staff and volunteers and the dissemination of information. In 2001, a survey was developed to determine the comfort level, familiarity, and use of computers and the Internet by active Oregon Master Gardeners (MGs). Basic demographic data was also collected. We found that 85% of respondents use computers and are very comfortable with computers and the Internet. This extensive use and comfort level suggests that the Internet may be an acceptable alternative to the traditional face-to-face training method for some Oregon MGs.
Management of Flooding Effects on Growth of Vegetable and Selected Field Crops
Authors: Rao Renuka , Li Yuncong
Published: December 2018

The review of effects of excessive soil water on performance of various vegetable crops and selected field crops indicates that in areas where temporary flooding hazards are expected during the growing season, crops can be selected on their relative ability to tolerate excessive moisture. Field crops are generally less sensitive than vegetable crops in terms of yield. In addition to the choice of crop species, planting dates could be shifted when possible by delaying dates of sowing or planting to avoid probable periods of flooding during the sensitive growth stages. In most instances, crops are more sensitive at their early developmental phase than at the later stages in terms of yield. Soil management practices like ridging and furrowing or making raised beds before planting is recommended. In addition, amelioration with foliar application of chemicals like nutrients, growth hormones and fungicides is also recommended to overcome nutritional deficiencies, hormonal imbalances and disease infections. Every effort of amelioration should be exerted at the earliest opportunity, since water damage to crops becomes more severe with longer flooding duration.
Use of Tropical Hibiscus for Instruction in Grafting
Authors: Mudge Kenneth W. , Hennigan Kelly , Podaras Peter
Published: December 2018

An instructional system involving tropical hibiscus (Hibiscus rosa-sinensis) was developed for teaching hands-on grafting skills as part of a traditional comprehensive course in plant propagation and also as part of an online grafting course. The advantages of using tropical hibiscus include the following: the absence of phenological constraints associated with seasonal changes in temperate woody species; the comparative ease of grafting hibiscus, assuring positive reinforcement of the student's learning experience; and the ease of propagating and growing hibiscus in the greenhouse for use at any time of year. The three methods included in these laboratory exercises are top wedge grafting—selected for its ease and high rate of success—T-budding, and chip budding. In addition to development of hands-on skills, the exercises are designed to teach students three of the most important requirements for successful grafting of any species, regardless of method. These requirements include cambial alignment, application of pressure between stock and scion, and avoidance of desiccation. An online rating tutorial and lab report form was developed for students to self-evaluate their grafted plants.
Agricultural Extension Models in South America: A Description of Systems in Use in Argentina, Brazil, Paraguay, and Uruguay
Authors: Arboleya Jorge , Restaino Ernesto
Published: December 2018

Information is presented about the linkages and relationships between the research and the transfer of technology-extension systems established within the countries that compose the Common Market of the South [Mercado Común del Sur (MERCOSUR)]. A brief description about the history of agricultural extension in each country is included along with descriptions of the major changes that have occurred within the last 10 years. This analysis allows a general comparison among the different extension approaches, and in particular regarding the institutional development for the system in the four countries of MERCOSUR.
International Perspectives in Horticultural Extension—A New Zealand Viewpoint
Authors: Warrington Ian J. , Wallace Barrie D. , Scarrow Sandy
Published: December 2018

The government-funded horticulture extension service, which provided a free service to New Zealand growers for nearly 50 years, was privatized in the late 1980s as part of major reforms to the primary production sector. That service had provided one-on-one on-farm visits, budget advice, provision of technical information, and facilitation of field days, workshops and discussion groups throughout the country. This government-funded service also provided policy advice, acted as an interface between industry and the research and development (R&D) sector, and responded to biosecurity incursions. A decade following privatization, the number of people involved in equivalent consultancy activities has almost halved with very little recruitment of new people into the profession. The emphasis is now much more towards providing advice on the overall management of an individual enterprise to ensure its financial viability, with less emphasis on technical transfer. Large horticultural businesses are increasingly employing specialists in-house who can provide technical solutions and advice on balance sheet management. Private consultancy companies now tend to work more at a local or regional level rather than at a national level and links with R&D providers have markedly weakened as research organisations are increasingly protecting intellectual property for their own commercial advantages and as information provision is now largely on a user-pays basis. In addition, biosecurity incursions over the past decade appear to have increased as a result of a weakened surveillance effort. Nonetheless, horticultural exports from New Zealand continue to grow at around 10% per annum and many sectors remain very competitive on world markets.
Inoculation with Vesicular-Arbuscular Mycorrhizal Fungi and Rhizobacteria Alters Nutrient Allocation and Flowering of Harlequin Flower
Authors: Scagel C.F.
Published: December 2018

We assessed whether addition of arbuscular mycorrhizal fungus (AMF) inoculum or rhizosphere organisms from AMF inoculum alters aspects of flowering, corm production, or corm quality of harlequin flower (Sparaxis tricolor) for two growth cycles after inoculation. Using pasteurized and nonpasteurized growth medium, plants were inoculated with either inoculum of the AMF, Glomus intraradices, or washings of the inoculum containing rhizobacteria. Shoots of plants inoculated with AMF emerged 2 days earlier than shoots on noninoculated plants or plants inoculated with inoculum washings. Flowers on AMF-inoculated plants opened 7-8 days earlier and plants produced more flowers per plant and per inflorescence than noninoculated plants. AMF-inoculated plants partitioned a higher proportion of biomass to cormel production than to daughter corms and had higher concentration and contents of zinc, sulfur, nitrogen, amino acids, and carbohydrates than corms from noninoculated plants. The rhizosphere organisms associated with the AMF inoculum influenced several measures of plant development, growth, and corm production suggesting that there are organisms associated with our AMF inoculum that have beneficial effects on the growth and productivity of harlequin flower. While inoculation with AMF can promote shoot emergence, leaf production, and flower production of harlequin flower, inoculation also alters aspects of biomass partitioning and corm composition that play an important role in the production of this crop for corms and cormels.
Urban Greening and Criminal behavior: A Geographic Information System Perspective
Authors: Snelgrove A.G. , Michael J.H. , Waliczek T.M. , Zajicek J.M.
Published: December 2018

A geographic information system (GIS) was used to create an interface to evaluate the relationship between the amount of greenness and the crime level within the city of Austin, Texas. Results indicated a statistically significant negative correlation between the incidence of crime committed in the Austin greater metropolitan area for the year 1995 and the amount of vegetation within the area in which those crimes occurred. Areas with less than the average mean greenness level in Austin had an increased amount of crime. Results indicated no statistically significant relationship between the level of greenness of the crime sites and the severity of the crimes committed, and income level appeared to have no statistically significant effect on the severity of crimes committed.
Efficacy of Ethephon on Vegetative Annuals
Authors: Starman Terri W. , Robinson Melissa C. , Eixmann Kristen L.
Published: December 2018

Plant response to ethephon treatment was tested on 27 cultivars of vegetative annuals that have spreading and trailing growth habits. A control treatment was compared to 500 and 1000 mg·L-1 (ppm) foliar spray treatments of ethephon. Plant height and/or width index were significantly reduced for 81% of the cultivars tested. Responsive cultivars were alternanthera (Alternanthera dentata), brachyscome (Brachyscome iberidifolia) `Toucan Tango'; calibrachoa (Calibrachoa hybrids) `Colorburst Red', `Million Bells Cherry Pink', and `Trailing Pink'; diascia (Diascia × hybrida) `Sunchimes Rose' and `Red Ace'; double impatiens (Impatiens wallerana) `Tioga Red' and `Tioga White'; sweetpotato vine (Ipomoea batatas) `Sweet Caroline Bronze'; lantana (Lantana camara) `Patriot Cherry' and `Samantha'; nemesia (Nemesia × hybrida) `Aromatica Dark Lavender', `Blue Bird', and `Blueberry Sachet'; nolana (Nolana paradoxa) `Blue Eyes'; ivy geranium (Pelargonium hybrida) `King of Balcon'; petunia (Petunia × hybrida) `Cascadia Pink', `Mini Bright Pink', and `Supertunia Mini Purple'; bacopa (Sutera cordata) `Bridal Showers'; and vinca vine (Vinca minor) `Illumination'. Ethephon was not effective on monopsis (Monopsis unidentata) `Royal Flush', persicaria (Persicaria microcephala) `Red Dragon', or calibrachoa `Liricashower Rose'. Different cultivars of petunia showed varied responses to ethephon treatments as did trailing snapdragon (Antirrhinum majus) `Chandelier Yellow' and `Luminaire Yellow'. Flower number was reduced in 55% of the cultivars due to a delay in flowering. The experiment finds efficacy of ethephon for most cultivars treated at rates greater than or equal to that used commercially, however more research is needed to determine optimum concentrations for the specific cultivars. Chemical name used: ethephon [(2-chloroethyl) phosphonic acid].
Testing the Potential Benefits of Brands in Horticultural Products: The Case of Oranges
Authors: Heiman Amir , Goldschmidt Eliezer E.
Published: December 2018

The share of brand-name fruit and vegetables is much lower than that for general foods or processed industrial foods. The paper analyzes consumers' choice between generic and brand-name products and shows that consumers' preferences for horticultural brands increase with their appreciation of quality and with a low quality of the generic products, and that brand preferences are affected by socio-economic variables. The theoretical findings are supported by an orange (Citrus sinensis) consumer survey held in the UK and Israel. We found that in both countries consumers assign a relatively low value to orange brands. Consumers who are willing to pay for better quality are those who perceive brands as more important.
Ground Bovine Bone as a Perlite Alternative in Horticultural Substrates
Authors: Evans Michael R.
Published: December 2018

Two grades of ground bovine bone were evaluated as potential alternatives to perlite in horticultural substrates. The bulk density of small and large bone-amended substrates was significantly higher than equivalent perlite-amended substrates. Large and small bone increased the air-filled pore space of sphagnum peat. However, at 10% and 20% (v/v), neither size of bone resulted in as high an air-filled pore space as equivalent amounts of perlite. At 30% and 40%, incorporation of small bone resulted in a similar air-filled pore space as incorporation of equivalent amounts of perlite, and incorporation of large bone resulted in a higher air-filled pore space than incorporation of equivalent amounts of perlite. Water-filled pore space and water-holding capacities of substrates were inversely related to air-filled pore space. When placed in a moist substrate, mineral elements within the bone were able to leach into the substrate over time. Substrates amended with 40% large and small bone had significantly higher concentrations of ammonium (NH4+), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), and chloride (Cl-) than the 40% perlite-containing substrates. Substrates amended with 40% large bone had similar concentrations of magnesium (Mg), sulfur (S), iron (Fe), and copper (Cu) while substrates amended with 40% small bone had higher levels of these elements than perlite-amended substrates. Substrate concentrations of nitrate (NO3-), manganese (Mn), zinc (Zn), and boron (B) were not different among the substrates after 4 weeks in the greenhouse. The pH, electrical conductivity (EC) and NH4+ levels of bone-amended substrates increased to levels significantly higher than recommended and resulted in rapid mortality of `Orbit Cardinal' geranium (Pelargonium × hortorum), `Cooler Blush' vinca (Catharanthus roseus), and `Dazzler Rose Star' impatiens (Impatiens walleriana) plants grown in bone-amended substrates. Therefore, ground bovine bone was not a feasible alternative to perlite for use in horticultural substrates.