bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship of Typical Core Temperatures After Hydrocooling on Retention of Different Quality Components in Sweet Cherry
Authors: Toivonen Peter M.A.
Published: December 2018

The research was conducted to first determine the commercial reality in regards to effectiveness of hydrocooling of sweet cherries (Prunus avium) at commercial packing houses. Temperature data obtained from the commercial studies were then used as a guide to evaluate the effect of small differences (0.5, 3, and 5 °C) in sweet cherry core temperature on the quality retention of ‘Sweetheart’ sweet cherries over 6 weeks of storage to simulate container shipment. Sweet cherry core temperatures after in-line hydrocooling and at the time of packing were generally around 3 or 5 °C. Once palletized and placed in commercial cold rooms, the internal boxes of a pallet did not cool any further. Only when a pallet was exposed to direct airflow from cooling coils did the exterior boxes in an assembled pallet show any further reduction in core temperature of packed sweet cherries. Experiments to evaluate the differences in quality retention at close to ideal core temperature (0.5 °C) vs. at more typical 3 or 5 °C core temperatures demonstrated significant decline when the two higher temperatures were maintained over 6 weeks of storage. Sweet cherry firmness, titratable acidity, and stem removal force value declines in storage were significantly affected by these small differences in core temperature, showing the best retention at 0.5 °C. Stem browning increased significantly with 3 or 5 °C storage by 6 weeks of storage. Decay was also significantly increased with warmer temperatures, but the results were variable likely due to differences in fruit infection at the time of harvest. Soluble solids were unaffected by storage temperature, and weight loss and pitting severity were somewhat affected. These results support the need for post packing cooling of sweet cherries as the core temperatures achieved by in-line hydrocoolers during packing do not reduce temperatures sufficiently to ensure good quality retention over longer periods of time that are required for container shipping to export markets. Therefore, forced-air cooling is recommended to further reduce sweet cherry temperatures in the box, before shipping.
Patch Budding Pecan: Girdling, Tipping, Age, and Size of Budwood and Rootstock for Budding; Girdling, 2,3,5-Triodobenzoic Acid and 6-Benzylaminopurine for Bud Forcing
Authors: Smith Michael W. , Goff William D.
Published: December 2018

Patch budding is a common propagation technique for pecan (Carya illinoinensis) commonly used in the central and western United States, but seldom used in the southeastern United States. Success rates vary, but 75% is normally an acceptable survival rate. Selected budwood and rootstock treatments were evaluated to improve budding success. Additional studies were conducted to evaluate bud forcing techniques that would leave the rootstock intact, allowing a second bud to be inserted if the first patch bud failed. Girdling exceptionally vigorous shoots at the base used for budwood improved success, but neither tip pruning shoots used for budwood or rootstock affected patch bud survival. Patch budding was more successful using budwood from 1-year-old branches than from current season shoots, a finding that greatly extends the window available for propagation using patch buds. The age of rootstock wood at the budding site did not affect patch bud survival. Girdling the rootstock immediately above the dormant patch bud was less effective than top removal for forcing the patch bud in the spring. Application of a lanolin paste of 0% to 5% 2,3,5-triodobenzoic acid (TIBA) or 0.02% 6-benzylaminopurine (BAP) to a girdle immediately above the patch bud was positively related to the percentage of patch buds forcing when tree tops were left intact. The combination of girdling, 5% TIBA, and 0.02% BAP resulted in 76% of the buds forcing compared with 73% forced using top removal. This approach damages trees less and enables a second chance for patch budding on a stronger tree.
Using Movable Light-emitting Diodes for Electricity Savings in a Plant Factory Growing Lettuce
Authors: Li Kun , Yang Qi-Chang , Tong Yu-Xin , Cheng Ruifeng
Published: December 2018

In this study, the effects of light-emitting diode (LED) panels with different illumination schedules and mounted above butterhead lettuce (Lactuca sativa var. capitata) seedlings on lettuce growth and photosynthesis were examined, and the performance of the vertical and horizontal movable system on energy savings was evaluated. The illumination schedules used were fixed LED [F-LED (four LED panels illuminated the area below)] and movable LED [M-LED (two LED panels moved left and right once per day to illuminate the same area as F-LED)] at distances of 10 and 30 cm above the seedlings. The plant yields were uniform in all LED treatments. The highest light utilization efficiencies and lowest electricity consumption were found for the treatments with irradiation from a shorter distance above the seedlings. The true leaf numbers and ascorbic acid concentrations were the highest in the M-LED and F-LED treatments at a distance above the seedlings of 10 cm, while the leaf lengths and sucrose concentrations in these groups were significantly lower than those in the 30-cm treatment. These results indicate that illumination with M-LED can halve the initial light source input while maintaining yield and that sustained illumination from a shorter distance above the seedlings is the main factor in electricity savings.
Pulsing With Low Concentration Gibberellin Plus Benzyladenine or Commercial Floral Preservatives Affect Postharvest Longevity, Quality, and Leaf Chlorosis of Cut Lilies and Gladioli
Authors: Ahmad Iftikhar , Dole John M. , Favero Bruno T.
Published: December 2018

Effects of pulsing with different concentrations of gibberellin plus benzyladenine (GA4+7 + BA), a proprietary mixture of GA4+7 plus BA in a commercial floral preservative (GA4+7 + BA + preservative), or a propriety mixture of sugar plus acidifier developed for bulbous flowers (floral bulb preservative) were studied on postharvest performance and quality of cut lily (Lilium hybrids) and gladiolus (Gladiolus hybrids) flowers. Pulsing of cut stems of lily with GA4+7 + BA at 5 or 2 mL·L−1 GA4+7 + BA + preservative for 20 hours at 3 ± 1 °C extended the vase life and controlled leaf chlorosis of ‘Cobra’ oriental lily and ‘Cappuccino’ and ‘Dot Com’ asiatic lily. Cut ‘Orange Art’ asiatic lily performed best when pulsed with GA4+7 + BA at 10 mg·L−1. For cut gladiolus, pulsing with GA4+7 + BA at 10 mg·L−1 extended the vase life of ‘Alice’, ‘Mammoth’, and ‘Passion’, while ‘Scarlet’ had the longest vase life when pulsed with 5 mg·L−1 GA4+7 + BA. GA4+7 + BA + preservative also extended the vase life and controlled leaf chlorosis, but the floral bulb preservative had no effect on vase life extension or preventing leaf chlorosis of lilies. Gladiolus cultivars had no or minor leaf chlorosis during vase period. Overall, overnight pulsing with GA4+7 + BA or GA4+7 + BA + preservative extended the vase life and prevented leaf chlorosis and can be used by growers and wholesalers for maintaining quality of cut stems.
Production of Bulbing Onion Overwintered in New Hampshire with Protection by Low Tunnels
Authors: Sideman Rebecca Grube , Brown Amanda , Hazzard Ruth , Bryant Heather
Published: December 2018

High demand for local produce year-round has led growers in the northeastern United States to experiment with fall planting of bulbing onion (Allium cepa) for spring harvest. Over two seasons, we evaluated survival, bolting, and bulbing of several cultivars of fall-planted onion in two sites in New Hampshire. Plants were seeded in August and September, and transplanted in September and October into raised beds covered with black plastic mulch. Low tunnels covered with 1.25-oz/yard2 rowcover and one layer of 6-mil-thick clear polyethylene were installed over the plants in late fall. Harvest dates ranged from 19 Apr. to 6 June in 2012, and from 22 May to 2 July in 2013. All onion cultivars showed high percentages of survival (65% to 100%). Cultivar, planting date, and the interaction between the two had a significant effect on the percentage of bolting and bulb diameter at harvest. In general, those planted later exhibited lower percentages of bolting and slightly smaller bulbs at harvest. Our work demonstrates that it is possible to harvest large bulbed onions in May and June in the northeastern United States in U.S. Department of Agriculture (USDA) hardiness zones 4B and 5B using low-tunnel season extension technology. This may provide additional marketing opportunities for growers in cold climates.
Refining Postharvest Handling Procedures Increased Cut Rose Vase Life
Authors: Moody Erin P. , Dole John M. , Barnes Jared
Published: December 2018

Various postharvest procedures were conducted on several rose (Rosa hybrida) cultivars to determine the effects on vase life, water uptake, change in fresh weight, stage of opening, and vase life termination criteria. Vase life was influenced by cultivar and vase solution. Commercial preservative solutions resulted in a longer vase life, smaller decrease in fresh weight than the controls, and smaller increase in water uptake. Vase life of nine cultivars in distilled water ranged from a low of 7.1 days for Queen 2000 to a high of 15.3 days for Forever Young. Flower termination criteria were also cultivar specific with Black Baccara, Classy, and Charlotte most prone to bent neck and blackening of petal tips. Exogenous ethylene at 0.4 or 4.0 μL·L−1 did not affect vase life but lowered water uptake. Application of the antiethylene agent silver thiosulfate (STS) at 0.2 mm concentration significantly improved vase life in five out of the nine cultivars (Anna, Charlotte, First Red, Freedom, and Konfetti) tested, but 1-methylcyclopropene (1-MCP) at 740 nL·L−1 did not improve vase life over the control. Both vase life and water uptake were reduced when more than one stem was placed in a vase; placing 10 stems in a vase shortened vase life by 1.4 days and impeded water uptake by up to 10.6 mL/stem per day. Increasing the amount of time stems remained dry before placing in a vase reduced vase life, but recutting immediately before placing in a vase minimized the decline. Increasing the amount of stem cut off the base up to 10 cm increased vase life.
Animal Tissue Compost as a Potential Substrate Amendment for Production of Four Annual Floriculture Crops
Authors: Getter Kristin L. , Rozeboom Dale W.
Published: December 2018

The objectives of this study were to determine the effectiveness of using animal tissue compost (ATC) as a substrate amendment for ornamental plant container production. The compost was produced using soiled sawdust bedding mixed with assorted animal tissues and actively composted for at least 6 months and cured for 6 to 10 months. Five substrate treatments that consisted of four different ratios of ATC and Canadian sphagnum peatmoss were formulated, all containing 20% medium grade horticultural perlite. Four species [geranium (Pelargonium ×hortorum ‘Maverick Red’), marigold (Tagetes erecta ‘Inca II Yellow’), pansy (Viola ×wittrockiana ‘Delta Premium Yellow Blotch’), and petunia (Petunia ×hybrida ‘Prostrate Wave Purple Improved’)] were evaluated with weekly plant measurements. Geranium and petunia exhibited 100% survival for all treatments. Marigold and pansy showed 100% survival for the control treatment (0% ATC) and the treatment with the smallest amount of ATC (20% ATC). Treatments for pansy and marigold with more than 40% ATC exhibited 40% to 90% survival. All ATC substrate treatments produced the same number of flowers and buds as the control in geranium, marigold, and petunia, while the treatments containing 20% to 60% of ATC for pansy exhibited more flowers and buds than the control. Measurements of pH and electrical conductivity (EC) varied based on treatment. Based on the species and the ratios of peat, ATC, and perlite tested here, ATC has the potential to be a peat extender in floriculture substrates when used in ratios of 20% or less.
Moving Toward Sustainability with Alternative Containers for Greenhouse and Nursery Crop Production: A Review and Research Update
Authors: Nambuthiri Susmitha , Fulcher Amy , Koeser Andrew K. , Geneve Robert , Niu Genhua
Published: December 2018

Market researchers have found that nursery and greenhouse production practices that reduce plastic use can increase consumer interest. However, there are broader crop performance, production efficiency, and environmental factors that must be considered before adopting containers made with alternative materials. This review highlights current commercially available alternative containers and parent materials. In addition, findings from recent and ongoing nursery, greenhouse, and landscape trials are synthesized, identifying common themes, inconsistencies, research gaps, and future research needs.
Weed Management in Autumn Fresh Market Spinach: A Nonchemical Alternative
Authors: Fontanelli Marco , Martelloni Luisa , Raffaelli Michele , Frasconi Christian , Ginanni Marco , Peruzzi Andrea
Published: December 2018

Physical rather than chemical treatments are preferred for integrated production and are required for organic production to ensure a sustainable production. Weed management in many horticultural crops is heavily constrained by the limited number of herbicides available. Physical weed control strategies, on the other hand, are essential to organic vegetable production and greatly assist conventional vegetable farmers. A physical weed control strategy was developed and compared with a standard chemical strategy within an integrated farming system in fresh market spinach (Spinacia oleracea). The experiment was conducted on a farm in the Serchio Valley (Tuscany, central Italy) in 2004 and 2005, where spinach is one of the most important crops. The physical weed control strategy consisted of a stale seedbed technique and postemergence treatments using various mechanical and thermal machines. The chemical weed control strategy consisted of a single postemergence herbicide treatment using phenmedipham at 15.8% in compliance with integrated production norms in Italy. Strategy performance was assessed in terms of weed density and biomass, total labor requirement, and crop yield. Compared with the chemical system, the physical system required a substantially larger labor input (19 vs. 6 h·ha−1), but like the chemical system, did not require hand weeding. In addition, the physical system reduced weed dry biomass at harvest by 50% and increased spinach fresh yield by 35%. Physical strategies therefore are a valid alternative to the use of herbicides in fresh market spinach and may be especially desirable given the increasing importance of nonchemical weed control in integrated, organic, and conventional farming systems in Europe and the United States.
Mustard Seed Meal for Management of Root-knot Nematode and Weeds in Tomato Production
Authors: Meyer Susan L.F. , Zasada Inga A. , Rupprecht Shannon M. , VanGessel Mark J. , Hooks Cerruti R.R. , Morra Matthew J. , Everts Kathryne L.
Published: December 2018

Mustard seed meals of indian mustard [InM (Brassica juncea)] and yellow mustard [YeM (Sinapis alba)], alone and combined, were tested for effects on tomato (Solanum lycopersicum) plants and for suppression of southern root-knot nematode [RKN (Meloidogyne incognita)] and weed populations. In the greenhouse, with all seed meal treatments applied at 0.25% total w/w soil, low tomato plant stands (up to 60% dying/dead) resulted from amendment with 3 YeM:1 InM, 1 YeM:1 InM, and YeM, applied right before transplant. Compared with untreated controls, low numbers of RKN eggs per gram root were consistently recorded from amendment with 3 YeM:1 InM. In a 2012 field study, incorporation of 1 YeM:1 InM (1700 lb/acre) resulted in lower tomato root biomass than fertilizer application (504 lb/acre), YeM or InM (each 1700 lb/acre). All treatments were applied with added fertilizer to achieve 100–102 lb/acre nitrogen, 7.4 lb/acre phosphorus, 74.7 lb/acre potassium, 6.0 lb/acre sulfur, and 1.0 lb/acre boron. The lowest numbers of RKN eggs per gram root (harvest 2012) were collected from plots amended with InM (1700 lb/acre), YeM (850 lb/acre), and 3 YeM:1 InM (1700 lb/acre), but the numbers were not significantly different from fertilizer only (504 lb/acre) controls. Highest and lowest tomato yields (numbers of fruit) in 2012 were recorded from YeM (850 lb/acre) and 3 YeM:1 InM (1700 lb/acre) amendments, respectively. In 2013, there were no significant differences among treatments in eggs per gram root or in tomato yields. No mustard seed meal treatment affected weed populations. At the tested rates, YeM seed meal showed potential for use in tomato beds but results were inconsistent between years.
Integrating Hoop House Construction and Environmental Data Interpretation into an Undergraduate General Education Plant Science Course
Authors: Uchanski Mark E. , Grover Kulbhushan , VanLeeuwen Dawn , Goss Ryan
Published: December 2018

Experiential learning can be used as part of the undergraduate curriculum to provide real-world experience in the classroom. A hands-on hoop house construction project was integrated into an undergraduate general education plant science course at New Mexico State University in Las Cruces. The objectives were to provide students with hands-on experience in hoop house construction and data collection and interpretation, evaluate students’ perception about the educational value of the hoop house construction activity and delivery methods, and evaluate individual student’s perceptions about their participation in the group activity and group dynamics. Eighty-four students were enrolled in Spring 2013 semester. Students were surveyed in a follow-up laboratory 10 weeks after the hoop house construction activity for data collection and reflection. The survey tool assessed the impacts of class materials, laboratory materials, and the laboratory teaching assistants (TAs) on the students’ learning experience: perceptions of group work, their role within their groups, and their participation. Ninety percent and 95% of the students agreed or strongly agreed knowledge of basic techniques and practical application of hoop house construction, respectively, were obtained in the exercise. Eighty-five percent of student respondents indicated a gain in their appreciation for scientific data collection and interpretation through this exercise. Also, a majority (65%) of the students agreed this hands-on task improved their appreciation for group activities indicating experiential learning group work during scheduled class time could be a useful tool for team building and other learning experiences. Finally, more than 90% of the students found this activity overall beneficial. We conclude that integrating hoop house construction and data collection into an undergraduate general education plant science course can be an effective way to enhance student learning.
Aqueous 1-Methylcyclopropene to Delay Ripening of ‘Kent’ Mango With or Without Quarantine Hot Water Treatment
Authors: Osuna-Garcia Jorge A. , Brecht Jeffrey K. , Huber Donald J. , Nolasco-Gonzalez Yolanda
Published: December 2018

Gaseous 1-methylcyclopropene (1-MCP) delays mango (Mangifera indica) fruit ripening, but requires 12 hours of application in sealed containers. In some fruit species, aqueous formulation applied as a postharvest dip for only 1 to 5 minutes has shown the same effectiveness as gaseous 1-MCP. This research was conducted to determine the effectiveness of aqueous 1-MCP on delay of the ripening process, extension of shelf life, and maintenance of fruit quality of ‘Kent’ mango fruit with or without quarantine hot water treatment (QHWT). Three experiments were conducted during the 2013 season in Mexico and Florida and during the 2014 season in Mexico. Aqueous 1-MCP caused delay of fruit ripening as shown by maintenance of fruit firmness, attenuation of flesh color development, and delayed increase of total soluble solids (TSS). However, it had a negative interaction with QHWT, causing surface spots and lenticel blackening to develop during shipping simulation [3 weeks at 12 ± 1 °C, 90% ± 5% relative humidity (RH)] and market simulation (7 days at 22 ± 2 °C, 75% ± 10% RH). This negative interaction was less when 1-MCP was applied before QHWT, somewhat higher when 1-MCP was applied after QHWT, and most severe when 1-MCP was applied after QHWT + hydrocooling. By contrast, the ripening of fruit treated with 1-MCP without QHWT was delayed without affecting external appearance. Thus, 1-MCP may be more useful for mango markets that do not require mandatory QHWT.
Use of Species-specific Controlled-release Fertilizer Rates to Manage Growth and Quality of Container Nursery Crops
Authors: Clark Mary Jane , Zheng Youbin
Published: December 2018

The objective of this study was to determine the optimal controlled-release fertilizer (CRF) application rates or ranges for the production of five 2-gal nursery crops. Plants were evaluated following fertilization with 19N–2.6P–10.8K plus minors, 8–9 month CRF incorporated at 0.15, 0.45, 0.75, 1.05, 1.35, and 1.65 kg·m−3 nitrogen (N). The five crops tested were bigleaf hydrangea (Hydrangea macrophylla), ‘Green Velvet’ boxwood (Buxus ×), ‘Magic Carpet’ spirea (Spiraea japonica), ‘Palace Purple’ coral bells (Heuchera micrantha), and rose of sharon (Hibiscus syriacus). Most plant growth characteristics (i.e., growth index, plant height, leaf area, and shoot dry weight) were greater in high vs. low CRF treatments at the final harvest. Low CRF rates negatively impacted overall appearance and marketability. The species-specific CRF range recommendations were 1.05 to 1.35 kg·m−3 N for rose of sharon, 0.75 to 1.05 kg·m−3 N for ‘Magic Carpet’ spirea, and 0.75 to 1.35 kg·m−3 N for bigleaf hydrangea and ‘Green Velvet’ boxwood, whereas the recommended CRF rate for ‘Palace Purple’ coral bells was 0.75 kg·m−3 N. Overall, species-specific CRF application rates can be used to manage growth and quality of containerized nursery crops during production in a temperate climate.
Managing Bitter Pit in ‘Honeycrisp’ Apples Grown in the Mid-Atlantic United States with Foliar-applied Calcium Chloride and Some Alternatives
Authors: Biggs Alan R. , Peck Gregory M.
Published: December 2018

Three separate experiments were conducted to test standard calcium chloride salt (CaCl2) rates and several new formulations of calcium (Ca) for amelioration of bitter pit, a Ca-related physiological disorder that affects fruit of many apple (Malus ×domestica) cultivars, including the popular cultivar Honeycrisp. Even small amounts of bitter pit damage make apples unmarketable. We evaluated various formulations of Ca to compare their effectiveness in controlling bitter pit, including proprietary Ca products (InCa™, Sysstem-Cal™, Vigor-Cal™, XD10, and XD505) with and without antitranspirant. Calcium chloride is the most common Ca product used to reduce bitter pit incidence, but it has negative impacts, such as phytotoxicity and corrosiveness. Of the products that were tested in 2011, XD10 at the high rate and XD505 are candidates for future study. In 2012, both the CaCl2 and XD10 treatments had lower bitter pit severity than the nontreated control, but only the CaCl2 treatments had a lower total percentage of fruit with bitter pit compared with the control. The antitranspirant reduced bitter pit incidence in one of three treatments. Full season Ca treatments and higher rates (up to 23.5 lb/acre per season of elemental Ca) are needed to significantly reduce bitter pit incidence in ‘Honeycrisp’ apples in the mid-Atlantic United States.
Paclobutrazol and Flurprimidol Control Stem Elongation of Potted Star of Bethlehem
Authors: Lee Judy , Gómez Miguel I. , Miller William B.
Published: December 2018

Plant growth regulators (PGRs) are effective tools for controlling potted plant growth. In this article, the effects of flurprimidol, paclobutrazol, and ethephon media drenches on stem elongation of star of bethlehem (Ornithogalum thyrsoides and Ornithogalum dubium) were investigated. At the lowest paclobutrazol (0.5 mg/pot) and flurprimidol rates (0.05 mg/pot) tested, plant height was reduced 20% to 35% compared with controls in all tested cultivars. Ethephon applied as a media drench when plants reached visible bud (VB) stage had no effect on plant height or flowering. A consumer preference survey of ‘Fire Star’ star of bethlehem (O. dubium) plant height showed that about 60% of participants preferred PGR-regulated plants. With every level of preference increase for shorter plants (on a scale of 1 to 5), participants were willing to pay $0.48 more for the shorter plant.
Influence of Calcium Foliar Fertilization on Plant Growth, Nutrient Concentrations, and Fruit Quality of Papaya
Authors: Madani Babak , Wall Marisa , Mirshekari Amin , Bah Alagie , Mohamed Mahmud Tengku Muda
Published: December 2018

Calcium (Ca) is a major plant nutrient that affects cell wall and plasma membrane formation and plays a key role in plant growth, biomass production, and function. Ca can be used to decrease fruit decay and increase firmness and shelf life. Different sources and concentrations of foliar-applied Ca were examined for the effects on nutrient concentration and growth of ‘Eksotika II’ papaya (Carica papaya) plants. Papaya seedlings were established in pots and irrigated with a standard nutrient solution in a net house. Four preharvest sprays were applied as foliar applications with three different sources of Ca {calcium chloride [CaCl2], calcium nitrate [Ca(NO3)2], and calcium propionate [Ca(C2H5COO)2]} at four concentrations (0, 60, 120, and 180 mg·L−1). Plant Ca concentration was unaffected by the different Ca sources. However, increased Ca concentration applied to the leaves enhanced plant accumulation of phosphorous and Ca in the plant, but decreased potassium (K) and magnesium (Mg) concentrations in the tissues. Plants that received Ca at 180 mg·L−1 had greater height and diameter than control plants. In a field trial with mature trees, preharvest applications of Ca (0, 4000, and 5400 mg·L−1) in the form of CaCl2 showed that increasing concentrations improved fruit Ca concentration, texture, and flavor; and decreased weight loss, Mg content, and apparent disease incidence of the fruit.
Effects of Paclobutrazol and Pinching on Ornamental Pepper
Authors: Mutlu Songul Sever , Agan Ece
Published: December 2018

Pinching, manual removal of shoot apices, and/or plant growth regulators (PGRs) are used to create commercially preferred compact and well-branched ornamental plants. The influence of paclobutrazol (PB) with and without pinching on the growth and fruit characteristics of a tall ornamental pepper (Capsicum annuum) was assessed 2, 4, 6, and 8 weeks after the initial treatment. PB was sprayed on pinched or nonpinched whole plants at 5, 10, or 15 ppm a.i. Pinching and PB reduced the plant height between 25% and 50% and the canopy diameter up to 8% and 17%, respectively. Height/diameter ratio (H/D) ranged from 1.0 for 10 and 15 ppm PB applied to pinched plants to 2.3 for control plants. Paclobutrazol increased the SPAD chlorophyll value and total fruit number, delayed fruit set, and decreased fruit diameter and dry weight. The relationship between PB and plant height and diameter, SPAD chlorophyll value, dry weight, and fruit number was best explained by a third-order polynomial (r2 = 0.83–0.99). Paclobutrazol may substitute costly pinching treatment for height control and may offer an economic advantage for commercial greenhouse operators.
Current Status of Children’s Gardens Within Public Gardens in the United States
Authors: Kwon Min Hyeong , Seo Changwan , Kim Jongyun , Kim Moonil , Pak Chun Ho , Lee Woo-Kyun
Published: December 2018

The purpose of this study was to identify the current status and future development of children’s gardens within public gardens in the United States and to examine their roles as places for children to explore natural environments. This study identified 776 public gardens and examined 163 of those gardens using a comprehensive online survey. The sampled public gardens were widely distributed throughout the United States, although they were located primarily in the eastern and western regions of the United States. We found that 55% of the 163 public gardens that we investigated included a children’s garden at the time of data collection, and 26.4% planned to add a children’s garden in the near future. Children’s gardens found within public gardens were typically in a botanical garden and were added after the public gardens were formed. Most of the children’s gardens had a stated purpose of providing children with environmental education by allowing them to experience the natural environment through play. Most children’s gardens occupied a small proportion, less than 1 acre, of the overall size of a public garden. We also found that demographic and socioeconomic factors influenced the development of children’s gardens within public gardens and public gardens in general.
Effects of Grafting Methods and Root Excision on Growth Characteristics of Grafted Muskmelon Plants
Authors: Guan Wenjing , Zhao Xin
Published: December 2018

Grafting has been used for controlling certain soilborne diseases and improving abiotic stress tolerance in muskmelon (Cucumis melo) production. Grafting methods may vary considerably among geographic regions and nurseries, while excision of rootstock roots before graft healing may also be practiced, which allows root regeneration of the grafted plants. In this greenhouse study, four grafting methods including hole insertion, one-cotyledon, noncotyledon, and tongue approach methods were examined for their impacts on plant growth and root characteristics of ‘Athena’ muskmelon grafted onto ‘Strong Tosa’ interspecific hybrid squash rootstock (Cucurbita maxima × C. moschata). Nongrafted rootstock and scion plants were included as controls. Both the grafted and nongrafted plants were examined with or without root excision. The practice of root excision was unsuccessful with the tongue approach method, while it did not exhibit significant effects on graft quality and growth of plants grafted with the one-cotyledon and hole insertion methods. Grafted plants with root excision started to show active and rapid root regeneration at 8 days after grafting (DAG) and reached similar root length and surface area as the root-intact plants at 16 DAG. Plants grafted with the noncotyledon method showed a different root growth pattern with decreased root length and surface area at 16 DAG. As a result, this method reduced the quality of grafted plants. No significant differences in plant growth characteristics were observed among the hole insertion, one-cotyledon, and tongue approach grafted plants.
Agricultural Plastics as Solid Waste: What are the Options for Disposal?
Authors: Hemphill Delbert D.
Published: December 2018

Agricultural plastics area significant contributor to solid waste disposal problems, particularly in areas with heavy use of plastic-covered greenhouses or mulch films. Field-burning and landfilling are no longer viable options for disposal in many areas. Reuse and reduced weight of films are two methods to reduce the amount of material requiring disposal. Recycling, incineration, and on-site degradation appear to be the most-promising technologies for disposal. Each technology has its drawbacks. These include dirt and pesticide residues on mulch films, the presence of stabilizers and photoactivators, possible limitations to recycling mixtures of types of plastics, and high costs for recycling and incineration facilities. This is an active area of research for many members of the American Society for Plasticulture.
The Effects of Reduced Tillage on the Soil Environment
Authors: Coolman R.M. , Hoyt G.D.
Published: December 2018

The physical characteristics of a particular soil affect its suitability for reduced tillage. Vegetable crops managed with reduced tillage generally will increase crop yields as drainage improves. Under reduced tillage, advantages over conventional tillage include better control of soil erosion, enhanced crop yields, soil water conservation, and more-efficient use of fossil fuel-based nonrenewable resources. Disadvantages with reduced tillage may include reduced soil temperature and increased soil moisture contents in udic soil moisture regimes, which can decrease crop yields.
Penjing: The Chinese Art of Bonsai
Authors: Zhou Wu-Zhong , Xu Xiao-Bai
Published: December 2018

More and more people have become very interested in bonsai, a unique art of gardening that originated in China. However, most people know about Japanese bonsai and have only scant knowledge of Chinese bonsai. This paper gives a brief introduction to the history, local schools, and patterns of the bonsai art in the Chinese tradition, as well as a list of plants used for bonsai in China.
The Future Use and Development of Expert System Technology in Horticulture
Authors: Crassweller R.M. , Travis J.W. , Heinemann P.H. , Rajotte E.G.
Published: December 2018

Decreasing resources and increasing complexity of horticultural crop production necessitate that new technologies be developed to transfer information to commercial producers. Expert systems (ES) have been cited as potential tools that can facilitate knowledge transfer. The definitions of an expert system, however, technically only indicates a computer program that simulates the thought processes of a human expert and, as such, does not supply all the facets necessary to assist commercial producers. The combination of databases, graphic capabilities, and textual information into a comprehensive program would provide a more complete package. To differentiate the two, we use the term decision support systems (DSS). The development, testing, and release of DSS, however, require greater commitment and interdisciplinary cooperation. Developing DSS fosters interstate, interregional, and international cooperation among researchers and extension personnel. Using systems developed in fruit production as examples, we outline the value of DSS to promote cooperation, the resources necessary to develop these systems; and the attitudinal change necessary to build the systems.
Apple Maturity Prediction: An Extension Tool to Aid Fruit Storage Decisions
Authors: Beaudry Randolph , Schwallir Philip , Lennington Marian
Published: December 2018

Due to the the extremely high level of competition in the marketplace for stored apple fruit, the need for quality maintenance during storage is critical. Quality analysis of fruit at harvest supports the contention that there is a harvest period during which fruit picked for long-term controlled-atmosphere storage maximize grower returns. The apple maturity program used in Michigan for determining this optimal harvest period-or window -incorporates a bloom date-based prediction and fruit maturity analyses. Techniques used in collecting and disseminating maturity information and its interpretation are discussed.
Intellectual Property Protection of Pelargoniums
Authors: Craig Richard
Published: December 2018

Pelargoniums represent a major floricultural crop in international markets. Intellectual property protection in the form of U.S. plant patents (200 since 1980) and European breeders' rights have been used for asexually propagated Pelargoniun. In addition, the hundreds of F', hybrid seed-reproduced cultivars are protected as trade secrets. International protection through the International Union for the Protection of New Varieties of Plants (UPOV) and the use of utility patents will accelerate breeding efforts; however, issues such as “essentially derived” and the farmer and research exemptions still must be resolved.
Carbon Dioxide Enrichment in Autotrophic Micropropagation: Methods and Advantages
Authors: Jeong Byoung Kyong , Fujiwara Kazuhiro , Kozai Toyoki
Published: December 2018

Autotrophic micropropagation has advantages over conventional micropropagation and can reduce costs of plantlet production. In this article, we describe advantages of autotrophic micropropagation and a practical and formulated method of enriching culture rooms with CO2.
Using Expressive Writing to Improve Horticultural Education
Authors: Foulk Doug S. , Hoover Emily E.
Published: December 2018

Horticulture students in an entry-level course (plant propagation) and an upper-level course (small fruit crop production) were assigned brief lecture-based writing tasks at the end of each class period. For the first 5 minutes of each subsequent class period, students divided into small groups to discuss their responses to the previous day s task and to generate questions related to the task topic. The class then reconvened as a whole for a question-and-answer session before the lecture was resumed. Students collected their task responses in a workbook that they turned in for experimental evaluation at the end of the quarter. When compared to previous and concurrent sections of the same courses, students engaging in the writing tasks more frequently posed questions in class, posed questions of increased complexity, and demonstrated improved ability to perform well on complex exam questions requiring integration and synthesis of information.
Blueberry Cultivars of North America
Authors: Moore James N.
Published: December 2018

The blueberry cultivar situation in North America is undergoing rapid change. Attempts to grow blueberries in non-traditional areas, and increased biotic and abiotic challenges in traditional production areas, are fueling the search for superior, adapted cultivars. This survey of all blueberry-producing states/provinces in the United States and Canada provides the current status and projected trends in blueberry cultivar use in North America. Most (86%) of current hectarage is comprised of 25 northern highbush, 10 rabbiteye, and two southern highbush cultivars. `Bluecrop' is the dominant northern highbush cultivar, with 35% of the highbush area, while `Tifblue' occupies 40% of the rabbiteye area. Some historically important cultivars, such as `Jersey', `Weymouth', and `Woodard' are in decline. New cultivars of all blueberry types are beginning to have a positive impact on the blueberry industry.
An Illustration of Biological Nitrogen Fixation for Plant Science Students
Authors: Graves William R. , Wilkins Lorna C.
Published: December 2018

A laboratory exercise for illustrating aspects of biological nitrogen fixation (BNP) to students in plant science courses is described. Surface-sterilized seeds of black locust (Robinia pseudoacacia L.) and soybean (Glycine max Merill) were sown together in plastic containers filled with a sterile, soilless medium. Containers were assigned randomly to treatments designed to show how inoculation with two strains of rhizobial bacteria and application of nitrate affect root nodulation and plant growth. Results demonstrated that BNF occurs in diverse legumes, that legumes vary in the strains of rhizobia with which they associate, that nodulation is inhibited by nitrate, and that dependency on BNP can reduce growth compared with plants provided nitrate.
Protecting Stone Fruit Flower Buds from Winter Freeze Damage
Authors: Willett M.J. , Proebsting E.L. , Redman R.E.
Published: December 2018

Flower buds of peach, apricot, and sweet cherry are killed by low temperatures during winter and spring. Frost protection measures used commonly in the spring are applied to freeze protection during the winter in the Yakima Valley of Washington. Critical temperatures change rapidly during winter. To succeed, winter freeze protection requires adequate inversions, equipment that operates at temperatures below -15C, and reliable estimates of critical temperatures for flower bud survival. Observations and experience have shown that inversions develop on most critical winter nights. Wind machines and orchard heaters will operate under severe low-temperamre conditions. Winter freeze protection has been practiced successfully on an increasing scale in the Yakima Valley for more than 20 years. Five packinghouses operate laboratories to measure critical temperatures. A computer model that estimates critical temperatures from daily or hourly air temperatures is being incorporated into these estimates.
Annual Culture of Globe Artichoke from Seed in Virginia
Authors: Welbaum Gregory E.
Published: December 2018

The globe artichoke (Cynara scolymus L.) is usually propagated vegetatively because plants grown from seed lack uniformity. Furthermore, in much of the United States, only a small percentage of plants grown from seed flower during the first season due to insufficient chilling for vernalization. Artichokes cannot be grown reliably as perennials without winter protection where temperatures are consistently below -10C. The new cultivars Imperial Star (IS) and Talpiot (TP) reportedly produce uniform plants from seed and a high percentage of flower heads (capitulum) the first year with minimal chilling. `Imperial Star' and TP were compared with the standard seed-propagated cultivars `Green Globe Improved' (GG) and `Grande Buerre' (GB). Plants of each cultivar were tested over a 3-year period in Blacksburg, Va., or for 1year in three other locations. Essentially all IS and GG plants flowered after receiving 1356 h of chilling at <10C. With 205 h of chilling, 83% of IS plants flowered compared to 25% for GG. No TP or GB plants flowered after receiving as much as 528 h of chilling. In the mountains of western Virginia, only IS plants established in the field in early May received sufficient chilling to produce flower heads during the late summer and early fall. June transplants did not flower because sufficient chilling was not obtained for vernalization. In warmer areas of central and eastern Virginia, fall establishment for spring harvest may yield a higher percentage of flowering plants compared to spring planting and summer harvest.
Physical Properties of Hawaiian Golf Course Sands
Authors: Murdoch Charles L. , Hensley David L.
Published: December 2018

Physical properties (particle size distribution, bulk density, capillary pore space, non-capillary pore space, hydraulic conductivity, and water retention) of three imported silica sands (Perth, Malaysian, and Newcastle), a man-made sand product (Mansand), and coral sand alone and in peatmoss mixtures were determined to evaluate their suitability as golf-green substrates. Based on laboratory evaluation of physical properties, the silica sands amended with peatmoss (15%) were superior to coral sand or crushed basalt (Mansand) amended with 15% peatmoss for use in high-traffic turfgrass areas.
Paperpot Transplanting Systems—Overview and Potential for Vegetable Production
Authors: Robb J.G. , Smith J.A. , Wilson R.G. , Yonts C.D.
Published: December 2018

The Paperpot system provides a relatively flexible approach to commercial transplanting of crops. Around the world, most of the research and application of this system has been on sugar beets. Compared to traditional hand-transplanted, field-grown, bare-root onions, there are several potential advantages of the Paperpot system, including reduced labor requirements, accuracy of placement, and fewer imported insect and disease problems. Comparison of three transplanters—carousel, BST, and chain-type—indicated the chain-type transplanter had lower labor inputs and a higher transplanting capacity than the other models. The BST transplanter was capable of placing 65% of the plants within a 3- to 5-inch plant spacing. The chain-type and carousel deposited 36% and 14%, respectively, within this same spacing. Yield was higher when onions were transplanted with the BST machine. This was attributed to the more-accurate placement of the onion plants. A four-row BST transplanter was capable of transplanting 0.4 acres/h of onions in field-scale trials.
Reaching Out to an Industry The North Carolina Experience with Its Nursery Industry
Authors: Safley C.D. , Bilderback T.E.
Published: December 2018

Many universities face tough decisions on how to allocate limited resources to serve a demanding clientele. Industry officials frequently perceive university researchers and extension specialists as losing touch with reality and working on irrelevant problems. In many situations, this perception is a result of the lack of communication among the parties involved. Research and Extension Commodity Overviews conducted by the College of Agriculture and Life Sciences at North Carolina State Univ. have proved to be an excellent way of improving communications between university personnel and the industries they support. This paper outlines the overview process and shows how this approach benefited the state's nursery industry and the university.
Horticultural Managers' Seminar: Using Extension Resources in Academic Teaching Programs
Authors: Ferguson J.J.
Published: December 2018

The experience and resources of extension specialists can be used in academic teaching programs within a horticultural managers' seminar for advanced undergraduate students, drawing on production, marketing, sales, and distribution managers to discuss application of horticultural principles in work situations and other complex issues facing agricultural managers. Guest speakers present an overview of their background, work responsibilities, management philosophy, and management practices. Students interact with speakers in this informal seminar and complete written evaluations of speakers and topics for discussion in later classes. This horticultural managers' seminar exposes students to the medley of problems and opportunities facing agricultural managers, uses the resources of extension faculty in academic teaching programs, and reinforces ties between commodity departments and their respective industries.
Dandelion Dilemma: A Decision Case in Turfgrass Management
Authors: Meyer Mary Hockenberry , Allen Phil
Published: December 2018

This paper presents a decision case concerning the application of herbicides to turfgrass at a public university housing project. Some residents opposed pesticide use, even though the grounds were infested with weeds. The chair of the grounds committee had to decide whether or not to use herbicides given the resulting social implications. The case was written for use in turfgrass management or introductory horticulture classes and possibly for turf and landscape personnel taught through extension education. Students assume the role of a decisionmaker in the complicated issue of pesticide use.
A Germination Study of Purple Sage
Authors: Love Belinda , Johnson Wayne S , Fernandez George C.J.
Published: December 2018

Germination of purple sage [Salvia dorrii (Kellogg) Abrams] seed was evaluated under 21 temperature combinations (day temperatures from 5 to 30C and night temperatures from 5 to 30C) in two experiments: 1) cool-moist stratification; and 2) sandpaper scarification, leaching with water, or gibberellic acid (GA3). The quadratic responses of weighted germination percentage (WGP), a combined index of germination percentage and speed of germination, were significant (P ≤ 0.05) for all treatments. The interaction of day and night temperatures was significant (P ≤ 0.05) only for the 2-week stratification treatments and for the Expt. 2 control. Stratification increased WGP over the control. Optimal WGP for all stratification treatments ranged from 46% to 51%. Optimal WGP was the same for both GA3 treatments. Optimal WGP for 0.29 mmol GA3 occurred at 16C night temperature and 22C day temperature, and for the 1.44 mmol GA3 treatment at 18C night and at 30C day temperature.
A Computerized, Multiple-chamber Controlled Freezing System
Authors: Barney D.L. , Mancuso C.J. , Finnerty T.L.
Published: December 2018

An inexpensive controlled freezing system that allows the temperature regime of eight modular sample chambers to be varied independently was constructed. A microcomputer-based data acquisition and control unit controls the freeze-thaw cycle in each of the chambers, as well as recording sample temperatures at desired time intervals. The computer also controls the freeze-thaw cycles in, and records data from, two differential thermal analysis units and records data from an electrical conductivity meter.