bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Mechanically Harvested Olive Storage Temperature and Duration on Oil Quality
Authors: Dag Arnon , Boim Smadar , Sobotin Yulya , Zipori Isaac
Published: December 2018

Most newly planted olive (Olea europaea L.) orchards are irrigated and harvested mechanically. We assessed the effects of olive storage temperature and duration on the resultant oil’s quality in three cultivars from modern orchards. Oil acidity increased with storage temperature and time, most markedly in ‘Barnea’ and least in ‘Koroneiki’. In ‘Koroneiki’, after 9 days in cool storage (4 and 10 °C), free fatty acid (FFA) level remained constant. Polyphenol (PP) content behaved differently among cultivars: in ‘Picual’, it was relatively invariable; in ‘Barnea’, it decreased moderately; and in ‘Koroneiki’, it decreased sharply to half of its initial value in 4 °C storage and one-sixth its initial value in room temperature storage after 23 days. Peroxide value (PV) did not increase during the storage period and did not appear to be affected by temperature. Thus, different cultivars show different responses to storage, and fruit originated from modern orchards are not necessarily more sensitive to storage than those from traditional orchards.
Height Control of ‘Hot Lips’ Hybrid Sage to Flurprimidol Substrate Drench
Authors: Fair Barbara A. , Whipker, Brian , McCall Ingram , Buhler Wayne
Published: December 2018

Sages (Salvia sp.) have long been popular as summer annuals, culinary herbs, and landscape perennials. We selected ‘Hot Lips’ hybrid sage [Salvia ×microphylla (Salvia greggii × S. microphylla)], a recently introduced perennial sage, to assess efficacy of the growth regulator flurprimidol for controlling height. Substrate drenches of flurprimidol at 0, 0.25, 0.50, 1.0, 2, and 4 mg per pot were applied using 240 mL of solution per pot on 17 June 2010. Plant height was recorded at treatment, 27 days after treatment (DAT), and 48 DAT. Flurprimidol drench concentrations of 0.25 mg per pot and higher controlled plant height by 20% to 41% 27 DAT and by 26% to 50% 48 DAT. While all treatments at 48 DAT produced a significantly shorter plant, concentrations between 0.25 to 1 mg would provide growers options for controlling plant growth by 26% to 44%. Using concentrations over 1.0 mg did not produce any additional control of height in hybrid sage.
Discovering Niche Markets for Elderberry Juice in the United States
Authors: Mohebalian Phillip M. , Cernusca Mihaela M. , Aguilar Francisco X.
Published: December 2018

This study contributes to the limited research on elderberry (Sambucus sp.) marketing and consumer preferences by eliciting consumers’ familiarity with elderberry products and identifying and profiling market segments for elderberry products. Results of a survey, distributed online to a sample of U.S. consumers, show one-third of respondents to be familiar with elderberry. The most common elderberry products sampled and purchased were juice, jelly, and wine. The consumer sample was divided into current and potential consumer groups. Health-conscious and less health-conscious consumer segments were identified within each group, composing four market segments in total. Current elderberry consumers (14% of respondents) are on average younger, more educated, and less price sensitive than potential consumers. They strongly prefer locally produced juices and elderberry juice to other types of juices. For this category of consumers, elderberry juice products can be positioned as novelty products that are perceived to be healthier and more expensive than other comparable products. Including a qualified health claim on the label would reinforce the health benefits of elderberry products and potentially increase less health-conscious consumers’ likelihood to purchase them. Market segments comprised of those who have not tried elderberry yet are characterized as appreciating locally produced products but as having greater price sensitivity than current consumers. Elderberry juice products can be introduced to these segments as value healthy products [similar to cranberry (Vaccinium macrocarpon)], emphasizing the health benefits and local origins while maintaining a lower price.
eApples: A Case Study in Using eXtension to Increase Access to Research-based Information
Authors: Hoover Emily E. , Marini Richard P. , Tepe Emily , Autio Wesley R. , Biggs Alan R. , Clements Jon M. , Crassweller Robert M. , Foster Daniel D. , Foster Melanie J. , Hirst Peter M. , Miller Diane Doud , Parker Michael L. , Peck Gregory M. , Racsko Jozsef , Robinson Terence L. , Warmund Michele R.
Published: December 2018

Researchers have collected a considerable amount of data relating to apple (Malus ×domestica) cultivars and rootstocks over the past 30 years, but much of this information is not easily accessible. The long-term goal of our working group is to increase access to this information using online technology available through eXtension. In eXtension, researchers and extension personnel are developing a community of practice (CoP) to increase the quality and amount of online information for individuals interested in our work [referred to as a community of interest (CoI)]. For this project, our CoI is broadly defined as commercial apple producers, nursery professionals, county extension educators, Extension Master Gardeners, home gardeners, and consumers. Our CoP is developing diverse educational tools, with the goals of increasing productivity, profitability, and sustainability for commercial apple production. Additionally, we will provide other members of our CoI access to research-based, reliable information on the culture of apples. We chose to begin our focus on cultivars and rootstocks adapted to the eastern United States and will add other U.S. regions as our resources and interest in our project grows.
An Online Plant Diagnostics Module for Extension Master Gardeners
Authors: Meyer Mary Hockenberry , Haynes Cynthia , Ellsworth Denise , Williams Sarah Ellis , Welty Celeste , Jeannette Karen
Published: December 2018

The North Central Consumer Horticulture Integrated Pest Management Working Group developed an online learning module entitled, “Introduction to Diagnostics for Master Gardener Volunteers: Approaches to Plant Pest Diagnosis.” The module is online in the campus or learn section of eXtension and is composed of three parts: part 1 covers the difficulties in diagnosing plant problems; part 2 discusses how to gather the information necessary for the diagnostic process; and part 3 covers the Ohio State Fact Sheet, “20 Questions on Plant Diagnostics.” The self-paced module takes a minimum of 2 hours to complete, although participants have access to the information for 10 weeks. The module costs $10 and the income is distributed between the module author(s), the state which the Extension Master Gardener (EMG) is from, and eXtension. Within 11 months, 451 people purchased the training. Participants reported a higher comfort and knowledge level of diagnostics after taking the training.
Multistate Efforts to Answer Consumer Horticulture Questions in eXtension
Authors: Durham Richard E. , Harker Candace
Published: December 2018

The Consumer Horticulture Community of Practice (CHCoP), responsible for the Gardens, Lawns, and Landscapes section of eXtension, has historically answered over 35% of the questions submitted to “Ask an Expert” (AaE)—the eXtension online, e-mail based question and answer system. Extension Master Gardener (EMG) volunteers were initially recruited to help answer questions and were responsible for resolving over 50% of the horticulture-tagged questions in 2008. With the number of questions related to horticulture nearly doubling on an annual basis, there was concern that EMGs alone would not be able to respond to all the questions. However, as eXtension has become more institutionalized in the land-grant system, county- and state-level extension staff have been encouraged to be involved in AaE. While EMG volunteers continue to play a vital role in answering questions, state extension specialists, and more so, county extension staff, are answering questions as well. This balanced approach seems more sustainable and at least 75% of questions are now being answered by an expert in the same state where the question originated.
Pecan Leaf Elemental Sufficiency Ranges and Fertilizer Recommendations
Authors: Smith Michael W. , Rohla Charles T. , Goff William D.
Published: December 2018

Pecan (Carya illinoinensis) leaf elemental concentrations are the industry standard to guide fertility programs. To provide meaningful information, a standard index tissue collected at a specific development stage is required along with established elemental sufficiency ranges. We report pecan leaf elemental sufficiency ranges used in Oklahoma that were developed based on research in Oklahoma and elsewhere. In addition, fertilizer recommendations, based on various leaf elemental concentrations, are included.
Potential Unintended Consequences Associated with Urban Fertilizer Bans in Florida—A Scientific Review
Authors: Hochmuth George , Nell Terril , Unruh J. Bryan , Trenholm Laurie , Sartain Jerry
Published: December 2018

Degraded inland and coastal water quality is a critical statewide concern in Florida and other states. Nutrients released from land-based human activities are present in water bodies resulting in algal blooms and increased eutrophication that impairs water bodies for their intended uses. There are differing approaches to addressing eutrophication, including voluntary adoption of current best management practices (BMPs) for nutrients, state regulation, or local county or municipal ordinances. The local ordinance, some including a summer (or so-called “wet season”) fertilizer ban or “blackout,” has been the chosen approach in some Florida counties and municipalities to address local water quality issues. Many components of these ordinances follow published BMPs, and there is agreement in the literature on the effectiveness of these practices for preventing nutrient losses from the landscape. However, there has been disagreement among stakeholders regarding the inclusion of a total fertilizer ban in a local ordinance. Regulators are asking about the best approach to controlling urban pollution and if banning fertilizer in the growing season would achieve the desired environmental protection and whether there are any potential unintended consequences associated with removing fertilizer from turfgrass growing in the summer months. The scientific literature documents the nature and scope of the water pollution problem, and numerous research reports have addressed fertilizer BMPs to prevent nutrient losses from the landscape. This article discusses the increased rate of eutrophication and reviews the pertinent national literature regarding managing urban landscape fertilization to protect water quality. Particular attention is given to fertilization practices during the active landscape plant (especially turfgrass) growth period that corresponds to the summer fertilizer bans in some Florida local ordinances. Therefore, special attention is paid to the question of what information is in the scientific literature and whether a fertilizer ban is the best way of achieving the goal of improving urban water quality. Research summarized in this review points to potential unintended consequences of increased nutrient losses from urban landscapes, particularly turfgrass, when proper, recommended fertilization and irrigation practices are not followed.
Characterization of ‘MD-2’ Pineapple Planting Density and Fertilization Using a Grower Survey
Authors: Leon Ramon G. , Kellon Delanie
Published: December 2018

‘MD-2’ is the predominant pineapple (Ananas comosus) cultivar for fresh fruit export worldwide. Costa Rica is one of the most important producers and exporters of ‘MD-2’, and many growers in this country have switched to this crop. However, growers have expressed concerns about the limited technical information available about how to grow this cultivar. We conducted a survey to gather information about the production practices implemented by commercial pineapple growers in Costa Rica and use this information to describe the response of the crop to these practices. Planting density was the most limiting factor affecting yield. Average planting density was 62,594 plants/ha although planting densities above 70,000 plants/ha produced highest yields. Average yields were 7130 and 4723 boxes/ha for the mother plant and ratoon crops, respectively. Fruit weight ranged from 1.5 to 2.0 kg and was not evidently affected by planting density or fertilization. Fertilization levels were between 632 and 520 kg·ha−1 nitrogen (N), 129 and 93 kg·ha−1 phosphorous (P), and 400 and 340 kg·ha−1 potassium for the mother plant and ratoon crops, respectively. In focus groups, growers considered that N and P levels could be reduced by 20% and 66% respectively, without jeopardizing yield. Results indicated that management practices must be modified for the ratoon crop to avoid yield reductions. The present study illustrated how a collaborative effort in which growers share information about their production practices can generate valuable data needed to identify adequate practices when funding and technical support are not available to experimentally generate these type of data.
In-ground Irrigation Systems Affect Lawn-watering Behaviors of Residential Homeowners
Authors: Bremer Dale J. , Keeley Steven J. , Jager Abigail , Fry Jack D. , Lavis Cathie
Published: December 2018

Urbanization is increasing the land area covered with turfgrasses, which may have implications for water quantity and quality. The largest sector of turfgrass is residential lawns. Our objectives were to compare lawn-irrigation perceptions, knowledge, and behaviors of residential homeowners with and without in-ground sprinkler systems (IGS and NIGS, respectively); homeowners were surveyed in three Kansas cities, each with distinctive water quantity and quality issues. Surveys were mailed to 15,500 homeowners in Wichita, 10,000 in Olathe, and 5000 in Salina; the return rate was 11% to 13%. Homeowners with IGS watered more frequently than NIGS; 67% to 90% of IGS and 19% to 31% of NIGS homeowners watered two to three times per week or more. More IGS homeowners watered routinely and applied the same amount of water each time than NIGS homeowners, who mostly watered and adjusted watering amounts based on lawn dryness. More IGS than NIGS homeowners wanted their lawn green all the time, followed lawn-care guidelines, and considered their neighborhood appearance important. Among IGS homeowners, 41% to 54% claimed to know how much water their lawns required compared with only 29% to 33% of NIGS homeowners. However, 65% to 83% in both groups did not know how much water they applied when they irrigated. About 7% to 9% of homeowners swept or blew clippings or lawn-care products into streets or storm drains; this percentage was unaffected by whether they had IGS or not. All homeowners’ lawn irrigation knowledge and habits must be improved to help conserve water and protect water quality, but educational efforts should concentrate on IGS homeowners because they water more frequently.
Selection and Budding Propagation of Native Bigtooth Maple for Water-conserving Landscapes
Authors: Richards Melody Reed , Rupp Larry A. , Kjelgren Roger , Rasmussen V. Philip
Published: December 2018

The potential of bigtooth maple (Acer grandidentatum) as a small, water-conserving landscape tree for the western United States is limited by the selection of superior accessions from a morphologically diverse gene pool and the ability to propagate wild plants in a nursery environment. Superior accessions were selected based primarily on red fall color. Aerial digital images taken during peak fall color in 2007 and 2008 were synchronized with flight global positioning system (GPS) track files using digital image editor software and visually compared with corresponding satellite images to determine the exact latitude and longitude of selected trees on the ground. Trees were physically located using GPS technology then visually evaluated for initial selection. Criteria included fall color, habitat, relative disease and insect resistance, bud quality, and plant form. From 56 observed trees of interest, six were selected for propagation. Through time-course experiments using multistemmed, bigtooth maple seedling rootstocks in a coppiced stoolbed, the optimum time for chip budding scions of wild accessions in northern Utah was determined to be July through mid-August. Further evaluation of accessions for use in the landscape industry is required.
Trumpetcreeper Control with Various Indole-3-Acetic Acid Mimics and Diflufenzopyr
Authors: Beeler Joseph E. , Armel Gregory R. , Brosnan James T. , Vargas Jose J. , Klingeman William E. , Koepke-Hill Rebecca M. , Bates Gary E. , Kopsell Dean A. , Flanagan Phillip C.
Published: December 2018

Trumpetcreeper (Campsis radicans) is a native, perennial, weedy vine of pastures, row crops, fence rows, and right-of-ways throughout most of the eastern United States. Field and greenhouse studies were conducted in 2008 and 2009 near Newport, TN, and in Knoxville, TN, to evaluate aminocyclopyrachlor-methyl and aminopyralid alone and in mixtures with 2,4-D and diflufenzopyr for selective trumpetcreeper control when applied postemergence in an abandoned nursery. These treatments were compared with commercial standards of dicamba and a prepackaged mixture of triclopyr plus 2,4-D. In the field, aminocyclopyrachlor-methyl alone controlled trumpetcreeper 77% to 93%, while aminopyralid alone only controlled trumpetcreeper 0% to 20% by 12 months after treatment (MAT). The addition of diflufenzopyr or 2,4-D to aminocyclopyrachlor-methyl did not improve trumpetcreeper control in the field; however, the addition of 2,4-D to aminopyralid improved control of trumpetcreeper from 50% to 58%. All aminocyclopyrachlor-methyl treatments controlled trumpetcreeper greater than or equal to dicamba and the prepackaged mixture of triclopyr plus 2,4-D. In the greenhouse, aminocyclopyrachlor and aminocyclopyrachlor-methyl applied at 8.75 to 35 g·ha−1 controlled trumpetcreeper 58% to 72% by 1 MAT. When both herbicides were applied at 70 g·ha−1, aminocyclopyrachlor controlled trumpetcreeper 64%, while aminocyclopyrachlor-methyl controlled trumpetcreeper 99%, similar to dicamba.
Costs of Food Safety Certification on Fresh Produce Farms in Vermont
Authors: Becot Florence A. , Nickerson Virginia , Conner David S. , Kolodinsky Jane M.
Published: December 2018

This article addresses the economic costs of good agricultural practices (GAPs) audits of small and medium size farms in Vermont. It focuses on the costs of infrastructure, equipment, and labor required to successfully pass a U.S. Department of Agriculture (USDA) GAPs audit. In-depth interviews and surveys of produce farmers in 2011 revealed that the cost of GAPs certification ranges between $37 and $54 per acre, and an additional 7 hours were required each week during the growing season. Based on this exploratory research, certifying all the farms in Vermont would cost between $228,216 and $3,019,114. Our study explored all the criteria of the certification and measured the costs of GAPs from planning stages to daily record keeping more than one year after the certification was achieved. This study provides information to farmers who are considering GAPs certification. It also provides background information to agricultural service providers and policymakers planning for the future of the fresh produce industry.
Experiential Learning Enhances Student Knowledge Retention in the Plant Sciences
Authors: Bauerle Taryn L. , Park Travis D.
Published: December 2018

Experiential learning can be an important part of an undergraduate curriculum in the sciences. A new course, The Nature of Plants, was developed to provide students across a broad range of majors with an in-depth study of plant science both basic and applied. The course was enriched by using a local natural area as an informal learning environment. We examined whether experiential learning improved homework scores among students who participated in a field trip by asking if simply attending the field trip increased the homework score or if participation in the tree climbing exercise had any additional benefit. Our results show participating in a field trip experience when coupled with a homework assignment increased student homework scores. Moreover, the tree climbing portion of the field trip increased homework scores particularly for students not in a science major. This research supports experiential learning and the value of field trips within science courses focused on a comprehensive exploration of plants.
Weed Control in a Newly Established Organic Vineyard
Authors: Olmstead Mercy , Miller Timothy W. , Bolton Callie S. , Miles Carol A.
Published: December 2018

Consumer demand for organic and sustainably produced products has increased the interest in organic wine grape (Vitis vinifera) production. However, organic production can be challenging, and weed management is a critical issue during the establishment of an organic vineyard. In 2009, the effectiveness of five cover crop treatments and cultivation regimes was evaluated for two years for weed control in a newly established organic vineyard of ‘Pinot noir précoce’ and ‘Madeleine angevine’ grape cultivars in northwestern Washington State. Alleyway management treatments were cultivation in alleyways with hand weeding in the vine row (control), grass cover crop which included perennial ryegrass (Lolium perenne ssp. perenne) and red fescue (Festuca rubra ssp. arenaria) seeded in the alleyway and in-row tillage with a specialty offset-type cultivator, winter wheat (Triticum aestivum) cover crop with in-row string-trimming, austrian winter pea (Pisum sativum ssp. sativum var. arvense) cover crop with in-row string-trimming, and winter wheat–austrian winter pea cover crop mix with in-row string-trimming. In 2009, weed dry biomass was lowest in the alleyway of the control (0.8 g·m−2) and offset cultivator treatments (6.3 g·m−2) on 3 Aug. and tended to be lowest in the alleyway of the control (4.8 g·m−2) and offset cultivator treatments (16.0 g·m−2) on 27 Sept. In the second year of establishment (2010), winter wheat and austrian winter pea were eliminated from the plots by mid-July, and white clover (Trifolium repens) and perennial ryegrass were the dominant weed species and accounted for a majority of the total weeds. On average over the two-year period, the control treatment required the most time for alleyway management (92 h·ha−1) followed by the offset cultivator treatment (64 h·ha−1), while the winter wheat, austrian winter pea, and winter wheat–austrian winter pea mixture required 32 to 42 h·ha−1. ‘Madeline angevine’ produced more shoot growth than ‘Pinot noir précoce’ in Sept. 2010 (42.3 and 25.9 cm respectively), and shoot growth of both cultivars in the control treatment was significantly longer (125.0 cm) than under any other treatment (55.4 to 93.0 cm), illustrating the importance of weed control during vineyard establishment. In this study, the most effective weed management regime, although also the most time consuming, included a vegetative-free zone around the vines (e.g., in-row) maintained by hand weeding and a cultivated alleyway.
Cellulosic Water and Polyacrylamide Gels Can Delay Wilting and Extend Watering Intervals for Potted Poinsettias Displayed in Interiorscapes
Authors: Stamps Robert H. , Savage Heidi M.
Published: December 2018

Poinsettias (Euphorbia pulcherrima) are popular for their colorful bracts and long keeping quality under indoor conditions. However, along with the long display life comes the maintenance issue of labor-intensive repeated waterings. Three experiments were conducted to determine whether using cellulosic water (CW) applied to the surface of the soilless growing medium as postproduction treatment could extend the days to wilt and intervals between waterings under simulated home/office conditions. CW is a gel composed of water bound in a cellulose matrix; as the cellulose is broken down the water is released. In addition, polyacrylamide (PAM) granules, applied dry into holes in the growing medium or hydrated to the medium surface, were evaluated for the same purpose in the final experiment. In the first experiment, pots containing cultivar Advent Red were treated with 0, 150, or 300 g of CW gel. In the second experiment, pots with ‘Prestige Early Red’ plants received 0, 125, or 250 g of CW gel. Pots were weighed and monitored for wilt daily. The days-to-wilt response was positively linear with CW application rates. Days to wilt (time between waterings) increased by over 3 days for each 100 g of CW applied to the pots during both Expts. 1 and 2 (y = 20 + 0.031x, r2 = 0.54 and y = 18.6 + 0.032x, r2 = 0.624, respectively, where y = days to wilt and x = grams of CW). In the third experiment, CW results were similar to those of the previous experiments. In addition, PAM initially also increased days to wilt compared with the control, with hydrated PAM applied at the same rate as CW providing the same benefits. However, PAM did not rehydrate adequately upon rewatering after the first wilt to delay the second wilt. This may have been due to fertilizer salts and to limited contact with the growing medium. Transpiration rates measured on the days before the untreated plants started wilting were not different among the treatments; therefore, the increased days to wilt provided by CW and PAM were due only to their providing additional water. Both CW and PAM gels were effective when used postproduction to supply supplemental water and lengthen the time period before the potted poinsettias wilted when held in interiorscapes.
Winter Stem Cutting Propagation of Heller’s Japanese Holly with and without Use of a Conventional Auxin Treatment
Authors: Blythe Eugene K. , Sibley Jeff L.
Published: December 2018

Heller’s japanese holly [Ilex crenata ‘Helleri’ (synonym: Ilex crenata f. helleri)] is a popular landscape plant in U.S. Department of Agriculture hardiness zones 5b to 8a because of its dwarf habit, slow growth rate, and dark green leaves. Plants can be propagated readily by stem cuttings and use of an auxin treatment is generally recommended to promote rooting. This study was conducted to determine if auxin treatment could be eliminated, thus reducing labor and chemical requirements in the cutting propagation process. In three experiments, terminal stem cuttings of Heller’s japanese holly were taken in winter, prepared both with and without use of a basal quick-dip in an auxin solution [2500 ppm indole-3-butyric acid (IBA) + 1250 ppm 1-naphthaleneacetic acid (NAA)], and rooted in a warm, high-humidity environment. Both nontreated cuttings and cuttings receiving a 1-second basal quick-dip in the auxin solution rooted at, or near, 100%. However, treatment of cuttings with auxin resulted in larger root systems on the rooted cuttings, which could allow earlier transplanting into larger nursery containers. No inhibition of new spring growth was exhibited by cuttings treated with auxin in comparison with nontreated cuttings.
Indaziflam Programs for Weed Control in Overseeded Bermudagrass Turf
Authors: Henry Gerald M. , Brosnan James T. , Breeden Greg K. , Cooper Tyler , Beck Leslie L. , Straw Chase M.
Published: December 2018

Indaziflam is an alkylazine herbicide that controls winter and summer annual weeds in bermudagrass (Cynodon sp.) turf by inhibiting cellulose biosynthesis. Research was conducted in Tennessee and Texas during 2010 and 2011 to evaluate the effects of indaziflam applications on overseeded perennial ryegrass (Lolium perenne) establishment and summer annual weed control. In Texas, perennial ryegrass cover on plots treated with indaziflam at 0.75 and 1.0 oz/acre measured 37% to 48% compared with 88% for the untreated control 257 days after initial treatment (DAIT). Perennial ryegrass cover following applications of indaziflam at 0.5 oz/acre measured 84% 257 DAIT and did not differ from the untreated control on any evaluation date. Inconsistent responses in crabgrass (Digitaria sp.) control with indaziflam at 0.5 oz/acre were observed in Tennessee and Texas. However, control was similar to the 0.75-oz/acre rate and prodiamine at 7.8 oz/acre at each location. A September application of indaziflam at 0.75 oz/acre followed by a sequential treatment at 0.5 oz/acre in March of the following year provided >90% control by June 2011. Indaziflam application regimes of this nature would allow for successful fall overseeding of perennial ryegrass every two years and control winter annual weed species such as annual bluegrass (Poa annua).
Growth and Quality Response of Five Landscape-grown Herbaceous Perennials to Nitrogen Fertilization at Five Rates
Authors: Shurberg Gitta , Shober Amy L. , Wiese Christine , Denny Geoffrey , Knox Gary W. , Moore Kimberly A. , Giurcanu Mihai C.
Published: December 2018

There is limited research regarding proper fertilization rates and timing for landscape-grown herbaceous perennials. Most current nitrogen (N) fertilizer recommendations for landscape-grown perennials are based on rates for woody landscape plants or on rates for greenhouse-grown perennials. In addition, most fertilizer guidelines are defined to achieve peak growth, which may not be the best indicator of desirable plant quality. Basing fertilizer input rates on plant quality levels rather than maximum growth may result in a lower fertilizer application rate and a reduction in excess fertilizer available for leaching. The objective of this research was to evaluate the response of landscape-grown herbaceous perennials to N fertilizer applied at five rates. Five herbaceous perennials [bush daisy (Gamolepis chrysanthemoides), ‘New Gold’ lantana (Lantana ×hybrid), ‘Mystic Spires’ salvia (Salvia longispicata ×farinacea), ‘Evergreen Giant’ liriope (Liriope muscari), and ‘White Christmas’ caladium (Caladium bicolor)] were transplanted into raised landscape beds containing subsoil fill in U.S. Department of Agriculture (USDA) hardiness zone 9a. Controlled-release N fertilizer was applied at an annual N rate of 0, 2, 4, 6, and 12 lb/1000 ft2 for 96 weeks. Plant size index (SI), tissue chlorophyll, and plant quality were measured every 6 weeks for 96 weeks. Flower cover was determined every 6 weeks from 42 to 96 weeks. Shoot biomass and tissue total Kjeldahl N (TKN) were measured at 96 weeks after planting (WAP). Regression analyses suggested that some species required in excess of 12 lb/1000 ft2 N to reach maximum size, chlorophyll content, and shoot biomass. However, plants exhibited quality ratings of good to excellent at annual N rates of 2 to 4 lb/1000 ft2 N per year. We suggest that these low to moderate levels of N fertilization (2 to 4 lb/1000 ft2 N per year) will provide sufficient N to produce acceptable size and quality herbaceous perennials in the landscape.
Fruit Composition and Sensory Attributes of Organic Heirloom Tomatoes as Affected by Grafting
Authors: Barrett Charles E. , Zhao Xin , Sims Charles A. , Brecht Jeffrey K. , Dreyer Eric Q. , Gao Zhifeng
Published: December 2018

Grafting has many purposes in vegetable production. It is used for control of soilborne pathogens, season extension in protected culture, and improving productivity in cucurbitaceous and solanaceous crops. Consumers desire heirloom tomatoes (Solanum lycopersicum) for their perceived excellent flavor. Heirloom tomatoes are susceptible to many soilborne diseases and may benefit from grafting onto more robust, disease-resistant rootstocks especially under organic production. In this two-year study, heirloom tomato ‘Brandywine’ was grafted onto tomato hybrid ‘Survivor’ and interspecific tomato hybrid ‘Multifort’ rootstocks to determine the effects of grafting on fruit quality attributes such as soluble solids content (SSC), pH, total titratable acidity (TTA), and vitamin C. Nongrafted and self-grafted ‘Brandywine’ tomatoes were included as controls. Consumer sensory tests were also conducted to assess the effects of grafting on overall appearance and acceptability, firmness, tomato flavor, and sweetness. No significant differences in vitamin C, SSC, pH, or TTA were found in fruit from the nongrafted, self-grafted, and ‘Brandywine’ grafted with the two rootstocks either year. The SSC of all tomatoes in 2010 was lower than that of 2011. In 2010, fruit from ‘Brandywine’ grafted onto the rootstock ‘Survivor’ was scored significantly lower in appearance, acceptability, and flavor than the nongrafted ‘Brandywine’ treatment. All grafted treatments resulted in a significant decrease in acceptability ratings in the consumer sensory test. No significant differences were observed between nongrafted and grafted treatments in 2011. Consumers who reported more frequent consumption of fresh tomato tended to give lower ratings for most sensory attributes evaluated. Harvest time and fruit ripeness need to be considered in future research to better understand the influence of grafting with selected rootstocks on fruit composition and sensory attributes of heirloom tomatoes.
Pennsylvania Statewide Winter Squash Cultivar Evaluation
Authors: Sánchez Elsa S. , Butzler Thomas M. , Stivers Lee J. , Elkner Timothy E. , Bogash Steven M. , Oesterling R. Eric , Orzolek Michael D.
Published: December 2018

Butternut, acorn, and buttercup/kabocha winter squash (Cucurbita sp.) cultivars were evaluated in a conventional system in central, southeastern, and southwestern Pennsylvania in 2010–11. Results from individual locations were used to create statewide recommendations, which are also relevant for the mid-Atlantic U.S. region. Additionally, butternut and acorn cultivars were evaluated in an organic system in central Pennsylvania. In a conventional system, butternut cultivars JWS6823, Betternut 401, Quantum, and Metro are recommended based on equal or higher marketable yield than the standard Waltham Butternut. Acorn squash cultivars that performed equally to or better than the standard, Tay Belle, were Table Star, Harlequin, and Autumn Delight. In the kabocha/buttercup category, ‘Sweet Mama’ and ‘Red Kuri’ had marketable yields not different from the standard ‘Sunshine’ in central and southeastern Pennsylvania. In the organic system, butternut cultivars JWS6823, Betternut 401, and Metro all had marketable yields not different from the standard Waltham Butternut. For acorn cultivars, Celebration yield did not differ from the standard Table Queen.
Taro Germplasm Evaluated for Resistance to Taro Leaf Blight
Authors: Miyasaka Susan C. , McCulloch Charles E. , Nelson Scot C.
Published: December 2018

Taro leaf blight (TLB), caused by the oomycete pathogen Phytophthora colocasiae, is a worldwide disease that threatens the sustainable cultivation of the tropical root crop taro (Colocasia esculenta). To evaluate taro germplasm from Asia, Hawai‘i, and several South Pacific Islands for resistance to TLB, 119 cultivars were planted along the Hamakua Coast of Hawai‘i (mean annual rainfall of 130 inches) in plots containing five or 10 plants that were replicated over time from 1993 through 2005. Fresh and dry weights of corms were measured after about nine months, with rotten portions removed and weighed. When epidemics of TLB occurred (in nine out of 12 years), visual estimates of disease severity on leaves were assessed using a modified Horsfall–Barratt scale. The correlations between mean dry weight yields for each cultivar and mean severity of TLB, and, respectively, between mean yields and mean severity of corm rots were calculated. As severity of TLB or severity of corm rots increased (suggesting increased susceptibility of particular cultivars to TLB or corm rots), mean dry weight yields decreased significantly (r2 = 0.37 and 0.22, respectively). “Multiple comparisons with the best” (MCB) were conducted on fresh and dry weight yields, severity of TLB, severity of corm rots, percentage dry matter of corm, and consumer acceptance. Five cultivars were found to be “among the best” with: 1) fresh or dry weight yields that did not differ from the highest level; 2) severity ratings for TLB that were significantly lower than the highest level, suggesting TLB resistance; and 3) percentage of corm rots that were lower than the highest level, suggesting disease resistance. These cultivars, four of which originated from Palau, were Dirratengadik, Merii, Ngesuas, Ochelochel, and Sawa Bastora. Two commercial cultivars from Hawai‘i, Bun Long and Maui Lehua, had fresh and dry weight yields that were significantly lower than the maximum and severity of TLB injury that did not differ from the highest level, indicating that conventional breeding of taro to improve TLB resistance could improve yields of commercial taro cultivars, particularly in areas where epidemics of TLB occur.
Are Learning Styles, Study Habits, and Performance Correlated in Woody Plant Identification Students?
Authors: Contreras Ryan N. , Velez Jonathan J. , Golembiewski Rob
Published: December 2018

New technologies such as online databases, interactive dichotomous keys, and online courses have changed the way some plant identification courses are delivered. These changing resources may create discrepancies between traditional instruction of landscape plant materials courses and the way modern students learn, which may result in students not meeting their potential. However, what resources students are using to study plant materials is unclear. We investigated the relationship between learning styles, study habits, and performance of students during two terms of woody landscape plant materials courses. To assess these relationships, we determined the characteristics of the participants and their preferred study method throughout the duration of the term as well as correlations between 1) preferred learning styles and performance, 2) preferred learning styles and preferred study method, and 3) performance and preferred study method. The participants in this study (n = 31) consisted of 14 males and 17 females. Of the 31 participants, 3 were freshmen, 3 were sophomores, 16 were juniors, 7 were seniors, and 2 were graduate students. Based on preference scores for learning style, 15 students were identified as visual learners, 3 as auditory, and 13 as kinesthetic learners. No significant relationships were observed between preferred learning style and performance or between preferred learning style and preferred study method. The two preferred study methods were using branch samples collected by the instructor and notecards created by students. No relationship existed between preferred study method and performance in the course. Our study provides information on study methods of woody plant identification students enrolled in a site-based course. We did not observe statistically significant relationships among preferred learning style, preferred study method, and course grade, but anecdotal evidence indicated students who prepared their own study aids by making notecards scored better in these courses.
Tolerance of Hooker’s Evening Primrose Transplants to Preemergence Herbicides
Authors: Bates Amber N. , Henry Gerald M. , McKenney Cynthia B.
Published: December 2018

No research has investigated the phytotoxic response of hooker’s evening primrose (Oenothera elata) plug transplants to preemergence herbicides. Varied phytotoxic responses of common evening primrose (Oenothera biennis) to preemergence herbicides suggest that options may exist for the safe control of weeds present within hooker’s evening primrose when grown as an agronomic field crop. Enhanced weed control during early establishment may reduce competition for water and nutrients as well as increase seed yield and oil content. Therefore, the objective of this research was to determine the phytotoxic effect of preemergence herbicides on hooker’s evening primrose plug transplants grown in the greenhouse. Research was conducted in 2010 and 2011 at the Plant and Soil Science greenhouse complex at Texas Tech University in Lubbock, TX. Herbicide treatments were applied on 13 July 2010 and 5 Apr. 2011 and consisted of oxadiazon at 3 lb/acre, isoxaben at 0.5 lb/acre, oryzalin at 2 lb/acre, prodiamine at 1.5 lb/acre, dithiopyr at 0.5 lb/acre, s-metolachlor at 1.8 lb/acre, pendimethalin at 0.6 lb/acre, and isoxaben + trifluralin at 2.5 lb/acre. One 4-month-old hooker’s evening primrose plug (2 inches wide) was transplanted into each pot (3 gal) 2 days after treatment (DAT). Dithiopyr and s-metolachlor treatments exhibited similar lack of phytotoxicity as the untreated control 7 DAT. Phytotoxicity ≥13% was observed for trifluralin + isoxaben, pendimethalin, prodiamine, oryzalin, isoxaben, and oxadiazon 7 DAT, with the highest level of phytotoxicity (24%) exhibited by trifluralin + isoxaben treatments. Hooker’s evening primrose phytotoxicity decreased (plants grew out of the damage) for all treatments except trifluralin + isoxaben, pendimethalin, and oryzalin 28 DAT. Oryzalin (16%) and trifluralin + isoxaben (60%) were the only two treatments that did not exhibit similar phytotoxicity to the untreated control 28 DAT. There were no significant differences in aboveground or belowground biomass nor plant growth index (PGI) of any of the treatments when compared with the untreated control 28 DAT. Based upon the results of this trial, pendimethalin, prodiamine, dithiopyr, s-metolachlor, oryzalin, isoxaben, and oxadiazon may be used for preemergence weed control in hooker’s evening primrose without causing excessive phytotoxicity (>20%), potential yield loss, or both. Trifluralin + isoxaben treatments exhibited 60% hooker’s evening primrose phytotoxicity 28 DAT, which resulted in too low of an initial plant stand to warrant use.
The Effect of Relationship Characteristics on Buying Fresh Flowers as Romantic Valentine’s Day Gifts
Authors: Lai Yen-Chun , Huang Li-Chun
Published: December 2018

A high percentage of fresh flowers sold are consumed as gifts in many countries, such as Taiwan, Japan, and the United States. As gift consumption is so important for the sales of fresh flowers, consumer behavior in floral gift giving is investigated in this research. This study explored the consumer decision to purchase fresh flowers as a romantic gift for Valentine’s Day based on 1) relationship stage, 2) affection, and 3) satisfaction with the relationship. The statistical results, based on the data of 366 valid questionnaires collected from a self-administered questionnaire survey, showed that the relationship stage of “personality need fulfillment,” the affection of “passion,” and relationship satisfaction significantly influenced the consumer decision of whether to purchase fresh flowers as romantic Valentine’s Day gifts. Consumers were more likely to buy their intimate partners fresh flowers when they perceived their personality need, such as the need of being loved, was fulfilled in the relationship. When strongly passionate about that relationship, they tended to give fresh flowers in conjunction with other gifts. However, when consumers were more satisfied with their romantic relationships, they were less likely to buy their intimate partners fresh flowers. The study results have valuable implications for florists’ business alliances and advertising campaign development for promoting floral gifts efficiently.
Susceptibility of Fraser, Canaan, and Nordmann Fir to Root Rot Incited by Phytophthora cactorum and Phytophthora drechsleri
Authors: Hoover Benjamin K. , Bates R.M.
Published: December 2018

The susceptibility of fraser fir (Abies fraseri), canaan fir (A. balsamea var. phanerolepis), and nordmann fir (A. nordmanniana) to phytophthora root rot (PRR) incited by Phytophthora cactorum or P. drechsleri was assessed in two experiments in central Pennsylvania. In an 8-week greenhouse study, seedlings and transplants growing in soilless substrate were inoculated with Phytophthora in flooded and non-flooded settings. In an 8-week outdoor study conducted in raised planting boxes filled with soil, transplants were inoculated with Phytophthora species in well-drained and poorly drained soil. Based on foliar disease ratings, mortality rates, and dry shoot and root weights, differences in susceptibility to P. cactorum and P. drechsleri existed between these true fir (Abies) species. Fraser fir was very susceptible to P. cactorum and P. drechsleri. Canaan fir had strong resistance to P. cactorum and P. drechsleri in well-drained settings but was susceptible in poorly drained settings. Nordmann fir had very strong resistance to P. cactorum and P. drechsleri in both well-drained and poorly drained settings.
Petunia Growth Response to Container Substrate Amended with Dewatered Aquaculture Effluent
Authors: Danaher Jason J. , Pickens Jeremy M. , Sibley Jeffrey L. , Chappell Jesse A. , Hanson Terrill R. , Boyd Claude E.
Published: December 2018

This experiment evaluated petunia (Petunia ×hybrida ‘Celebrity’) growth response to amending a commercial potting mix (F3B) with different amounts of dewatered aquaculture effluent (AE) and fertigating with a water-soluble, inorganic fertilizer or municipal water. The experiment was a completely randomized 2 × 5 factorial design with eight single-pot replications per treatment. At 39 days after planting (DAP), a significant (P ≤ 0.05) substrate and water interaction existed for petunia growth index (GI), bloom count (BC), fresh weight (FW), and dry weight (DW). The 100% F3B, 5% AE, and 10% AE substrates benefited with a significantly (P ≤ 0.05) greater BC, FW, and DW when fertigation was used; however, the water source had no effect on petunia BC, FW, or DW for levels ≥25% AE. Fertigating substrates amended with increasing levels of AE did not improve petunia growth. Conversely, when applying municipal water plant, FW and DW were the greatest using 25% AE.
Production Trends in Mature Macadamia Orchards and the Effects of Selective Limb Removal, Side-hedging, and Topping on Yield, Nut Characteristics, Tree Size, and Economics
Authors: McFadyen Lisa , Robertson David , Sedgley Margaret , Kristiansen Paul , Olesen Trevor
Published: December 2018

Yields of macadamia (Macadamia integrifolia, M. tetraphylla, and hybrids) orchards tend to increase with increasing tree size up to ≈94% light interception. Beyond this, there is some indication that crowding leads to yield decline, but the evidence is limited to one site. Increasing tree size and orchard crowding also present numerous management problems, including soil erosion, harvest delays, and increased pest and disease pressure. The aim of this study was to better characterize long-term yield trends in mature orchards and to assess the effects of manual and mechanical pruning strategies on yield, nut characteristics, tree size, and economics. We monitored yield at four sites in mature ‘344’ and ‘246’ orchards for up to seven years and confirmed a decline in yield with crowding for three of the sites. There was a small increase in yield over time at the fourth site, which may reflect the lower initial level of crowding and shorter monitoring period compared with the other sites, and highlights the need for long-term records to establish yield trends. Pruning to remove several large limbs from ‘246’ trees to improve light penetration into the canopy increased yield relative to control trees but the effect was short-lived and not cost-effective. Removal of a codominant leader from ‘344’ trees reduced yield by 21%. Annual side-hedging of ‘246’ trees reduced yield by 12% and mechanical topping of ‘344’ trees caused a substantial reduction in yield of up to 50%. Removal of limbs in the upper canopy to reduce the height of ‘344’ trees had less effect on yield than topping but re-pruning was not practical because of the extensive regrowth around the pruning cuts. Tree size control is necessary for efficient orchard management, but in this study, pruning strategies that controlled tree size also reduced yield. Research into the physiological response to pruning in macadamia is required to improve outcomes.