bluuebunny/crossref_metadata_2025 huggingface dataset:
The Suitability of Expanded Shale as an Amendment for Clay Soils
Authors: Sloan John J. , Mackay Wayne A. , Colbaugh Phil , George Steve W. , Feagley Sam
Published: December 2018

Excessive soil moisture in clay soils can cause poor aeration and adversely affect plant growth. Small [1 to 3 mm (0.039 to 0.118 inches)] and large [3 to 6 mm (0.118 to 0.354 inches)] diameter expanded shales (ExSh), quartz sand, sphagnum peatmoss (SPM), and cottonseed hulls (CH) were evaluated as soil amendments for Austin silty clay soil. A 3-inch (7.6-cm) layer of each amendment was incorporated to a depth of 6 inches (15.2 cm), resulting in a 1:1 mixture by volume. Pansies (Viola × wittrockiana `Crown Azure Blue') were grown from December to June, followed by scaevola (Scaevola aemula `New Wonder') from June to November for two growing seasons. Foliage quality and extent of flowering were evaluated biweekly. Pansy root weights and above-ground biomass were quantified at the end of each growing season. None of the amendments significantly affected pansy foliage quality or the number of blooms per plant. Small diameter ExSh and SPM decreased pansy nitrogen content the first year after application, but not the second. During the first growing season, when soils were frequently saturated due to excessive rainfall, pansy root weights were significantly higher in soils amended with the small and large diameter ExSh. Large diameter ExSh treatments significantly increased the survival rate of transplanted scaevola plants and also the quality of foliage and percent blossom coverage during both growing seasons. Cottonseed hulls also increased scaevola survival for both growing seasons, but did not consistently improve scaevola foliage quality or bloom coverage. Of the five amendments tested, large diameter ExSh consistently improved overall plant performance more than the other amendments.
Sunflower Seed Hulls as Substrate for the Cultivation of Shiitake Mushrooms
Authors: Curvetto Néstor , Figlas Débora , Delmastro Silvia
Published: December 2018

Nutritive agar formulations with additions of poplar (Populus alba) sawdust, wheat (Triticum durum) bran, or milled sunflower (Helianthus annuus) seed hulls (SSH) were evaluated for mycelium cultivation of shiitake (Lentinula edodes), in petri dishes. Sawdust, 2, 3 and 4 g·L-1 (0.27, 0.40 and 0.53 oz/gal) added to MYA (malt, yeast extract and agar) medium did not improve the mycelium growth rate, while media that included 1, 2, and 3 g·L-1 (0.13, 0.27, and 0.40 oz/gal) wheat bran or 2, 3, and 4 g·L-1 (0.27, 0.40, and 0.53 oz/gal) milled SSH exhibited a significant increase in the mycelium growth rate, at 25 °C (77 °F). The use of SSH obtained directly from the oil industry was evaluated as a substrate for the cultivation of shiitake mushroom via synthetic logs in plastic bags. A linear growth test was used to previously assay the mycelium growth rate in substrate compositions with different contents of SSH, wheat bran, and poplar sawdust, at 25 °C. The largest mycelial growth rates were 2.75, 2.88, and 2.93 mm·d-1 (0.108, 0.113, and 0.115 inch/day) for the substrates formulated with 8 SSH: 2 wheat bran, 9 SSH: 1 poplar sawdust, and 8 SSH: 1 wheat bran: 1 poplar sawdust by weight, respectively. The synthetic logs showed a daily production rate of 2 kg shiitake/100 kg dry substrate for a 55 days cycle production with a simple formula containing 37.5% SSH, 0.5% calcium carbonate (CaCO3), 2% calcium sulfate (CaSO4), and 60% water. Addition of wheat bran to the SSH-based synthetic log produced no significant differences on biological efficiency, mushroom production, or productivity.
Chilling Duration Affects Foliar Budbreak Of Linden Cultivars
Authors: Wilson Barrett C. , Sibley Jeff L. , Altland James E.
Published: December 2018

A study evaluating the effects of varying levels of chilling on foliar budbreak of linden (Tilia spp.) culivars was initiated in 1999 in Auburn, Ala. [lat. 32°36'N, long. 85°29'W, elevation 709 ft (216m), USDA Hardiness Zone 8a]. Littleleaf linden (T. cordata) `Greenspire' and `Fairview' required the most chilling to produce measurable budbreak and exhibited the lowest budbreak percentages. Silver linden (T. tomentosa) `Sterling' and american linden (T. americana) `Redmond' needed the fewest hours of chilling to produce budbreak and exhibited the highest budbreak percentages. `Sterling' was the top performer in foliar budbreak percentage and in subsequent growth. Although `Redmond' attained high budbreak numbers, its overall growth during the following growing season was inferior to that of `Sterling', `Greenspire' and `Fairview'. This information can contribute to the development of regional planting recommendations, which can aid in the selection of lindens suitable for the area in which they will be grown. Calculated r2 values indicated the models used provided a good fit to the data for all cultivars.
Production of High-quality Tomato Transplants with a Novel Buffered Fertilizer
Authors: Vavrina Charles S. , Brown Kathleen M. , Snyder Robert , Orzolek Mike , Lynch Jonathan P.
Published: December 2018

`FTE 30' tomato (Lycopersicon esculentum) transplants were produced in Florida under standard commercial conditions and supplied with one of six treatments: zero, low (20% of the control rate), or high (control) super-phosphate (SP) fertilizer, or 0.5%, 1%, or 2% buffered-phosphorous fertilizer (Al-P). Growth characteristics were evaluated for four sets of transplants, produced in January, April, May, and August. Two sets of transplants were grown in the field in Florida (started in January and August) and one set was grown in Pennsylvania during the summer (started in May). Phosphorus concentration in leachate was measured weekly from one crop. Plants grown with Al-P showed a 72% to 88% reduction in P released in leachate compared with the high SP control. Transplants produced with 1% or 2% Al-P were of equal size and quality compared with transplants produced with conventional (high SP) fertilization, and had greater total root length and specific root length (length per unit root weight). Transplants grown with 0.5% Al-P were sometimes smaller than other fertilized treatments, while no-P plants were very small and grew slowly after transplanting. There were no significant differences in growth, yield, or fruit quality of plants fromtransplants grown with 1% or 2% Al-P or high SP at either site. Therefore high quality tomato transplants can be produced using buffered-P fertilizer, while reducing P leaching from the containers.
High Temperature Solarization for Production of Weed-free Container Soils and Potting Mixes
Authors: Prather Timothy S. , Stapleton James J. , Mallek Susan B. , Ruiz Tarcisio S. , Elmore Clyde L.
Published: December 2018

A double-tent solarization technique, which accumulates higher soil temperatures than solarization of open fields, was recently approved by the California Department of Food and Agriculture (CDFA) as a nematicidal treatment for container nurseries. Due to the need for broad-spectrum pest control in container nursery settings, this technique was tested to determine its usefulness as an herbicidal treatment. Laboratory-derived thermal death dosages (temperatur × time) for several weed species important in California, including common purslane (Portulaca oleracea), tumble pigweed (Amaranthus albus), and black nightshade (Solanum nigrum), were previously determined and the data were used as guidelines for devising treatment duration in this study. In two field experiments conducted in 1999 and 2000 to validate the laboratory data, moist soil was placed in black polyethylene planting bags [3.8 L (1 gal) volume], artificially infested with seeds of the three test species, and subjected to 0 to 24 hours of double-tent solarization after reaching a threshold temperature of 60 °C (140 °F) (about 1.5 to 2.0 h after initiation of the experiment). In 1999, samples were removed at 2, 4, 20, and 24 hours after reaching the 60 °C threshold, then incubated to ameliorate possible secondary dormancy effects. Seeds failed to germinate in any of the solarized treatments. In 2000, samples were removed at 0, 1, 2, and 6 h after reaching 60 °C. Again, apart from the nonsolarized control treatment, all weed seeds failed to germinate at any of the sampling periods, in accordance with prior laboratory thermal death results. Reference tests to estimate effects of container size on soil heating showed that soil in smaller container sizes (soil volume) reached higher temperatures, and were maintained at high temperature [above 60 °C (140 °F)] for a longer period of time, than larger container sizes. The double-tent solarization technique can be used by commercial growers and household gardeners to effectively and inexpensively produce weed-free soil and potting mixes in warmer climatic areas.
In-season Soil Nitrate Testing as a Guide to Nitrogen Management for Annual Crops
Authors: Heckman J.R.
Published: December 2018

In-season soil nitrate testing is most useful when there is reason to believe, based on field history, that N availability may be adequate. These reasons may include soil organic matter content, applied manure, compost, legumes in the rotation, or residual N fertilizer. Soil nitrate testing is not helpful when crops are grown on sandy, low organic matter content soils that are known from experience to be N deficient. Soil nitrate testing is useful for annual crops such as vegetables or corn for which supplemental N fertilization is a concern. Soil nitrate tests must be performed at critical crop growth stages, and the results must be obtained rapidly to make important decisions about the need for N fertilization. Soil nitrate-N (NO3-N) concentrations in the range of 25 to 30 mg·kg-1 (ppm) indicate sufficiency for most crops, but N fertilizer practice should be adjusted based on local extension recommendations.
Experiences with Weed Discs and Other Nonchemical Alternatives for Container Weed Control
Authors: Chong Calvin
Published: December 2018

The first weed disc (Weed Guard) was introduced to Ontario in the early 1980s. They were made of semirigid plastic similar to 45-rpm records. Small holes allow water to penetrate but weeds germinating on the substrate often grow through them. In the 1990s, we obtained 85% reduction of container weeds using discs made from geotextile fabric (Mori Guard) or foam (similar to polyfoam used for container winter protection). The foam disc tended to curl upward at the edges, become easily windblown, and tended to partially expose the surface of the container mix. During the past 15 years, we have annually reused the same fabric discs (now unavailable due to high unit cost), and have tested various other weed discs, including several new-generation types and also the Mori Weed Bag. The new-generation discs are fabricated from materials such as fabric (Tex-R Geodisc), pressed peat moss (Biodisc), corrugated cardboard (Corrudisc), and plastic (Enviro LID). Both Tex-R Geodisc and Enviro LID were as effective or better in controlling weeds than weekly hand-weeding, herbicides, or the Mori Guard fabric disc. The Mori Weed Bag, a patented black polyethylene sleeve with prepunched holes fitted around the container like a florist's plant prepared for market, is used effectively and almost exclusively by one Ontario nursery. We also tested two types of insulated blanket covers, which when placed around the ball of above-ground container-grown trees, prevented weed growth during the summer and also protected the root ball against cold during the winter. We introduced the garbage bag sleeve, the ultimate no-weed method for pot-in-pot tree culture, which also reduces water use and frequency of irrigation. Due to factors such as under-performance, insufficient demand, and/or high costs, only certain discs are currently manufactured: Weed Guard, Tex-R Geodisc, Biodisc, and Enviro LID. The Mori Weed Bag is available but not the insulated blankets.
Detection of Seedborne Pathogens
Authors: Walcott Ron R.
Published: December 2018

Plant pathogens present a serious threat to seedling establishment and the potential for plant disease epidemics under greenhouse conditions is great. Hence, pathogen exclusion by detection and elimination of infested seedlots remains a requisite tactic for seedling production and disease management. Unfortunately, the numbers of contaminated seed within a lot may be low and infested seed may be asymptomatic making their detection difficult. To address these issues seed detection assays have been developed, but many of them have shortcomings that reduce their effectiveness. Examples of frequently used seed assays include visual examination, selective media, seedling grow-out and serological assays which, while appropriate for some pathogens, often display inadequate levels of sensitivity and specificity. Recently, the polymerase chain reaction (PCR) has emerged as a tool for detecting microorganisms in many diverse environments. Thus far, it is clear that DNA-based detection systems exhibit higher levels sensitivity than conventional techniques. Unfortunately, PCR-based seed tests require the extraction of PCR-quality DNA from target organisms in backgrounds of saprophytic organisms and inhibitory seed-derived compounds. The inability to efficiently extract PCR-quality DNA from seeds has restricted the acceptance and application of PCR for seed detection. To overcome these limitations several modified PCR protocols have been developed including selective target colony enrichment followed by PCR (BIO-PCR) and immunomagnetic separation and PCR. These techniques seek to selectively concentrate or increase target organism populations to enhance detection and have been successfully applied for detecting bacteria in seed. Other techniques with great potential for rapid detection of seedborne pathogens include magnetic capture hybridization and PCR, and DNA-chip technology. Ultimately, PCR will be available for the detection of all seedborne pathogens and may supersede conventional detection methods.
Fertigation Uniformity Affected by Injector Type
Authors: Bracy Regina P. , Parish Richard L. , Rosendale Roger M.
Published: December 2018

Application uniformity of fertilizers and pesticides is critical for crop uniformity, but can be difficult to determine when a fertilizer or chemical (fertigation/chemigation) is applied via drip irrigation or deep irrigation tape. Three injectors (venturi, pump, and proportional) were compared in a greenhouse experiment with a continuous-injecting experimental plot injector for fertilizer distribution uniformity in a drip irrigation system. Injection rate and solution volume were evaluated in a field experiment. Injection rate had a significant effect on fertilizer distribution uniformity. Better fertilizer distribution in the greenhouse experiment was obtained with venturi and proportional injectors. In the field, better distribution was obtained with the 1 gal/min (0.06 L·s-1) positive-displacement pump than with the 3 gal/min (0.19 L·s-1) pump. Injection times were longer with these injectors than with the other treatments, with the exception of the continuous injector. Injectors tested in this experiment will give uniform fertilizer distribution if the injector is properly sized with the water flow rate of the system.
Origin of Multiple Trunks Affects Crapemyrtle Posttransplant Establishment
Authors: Arnold Michael A.
Published: December 2018

Bare-root 17.5-inch-tall (44.45-cm) `Sarah's Favorite' crapemyrtle (Lagerstroemia indica L.) liners were grown in #3 [2.75-gal (10.4-L)] black plastic containers and trained to one, three, or five trunks by one of two methods. Half of the plants were established from multiple liners with each trained to form one of the trunks. The others were established by planting a single liner in each container, pruning them back to within 2 inches (5.1 cm) from the substrate surface, and then training elongating buds or adventitious shoots to the desired number of trunks. Once plants reached a marketable size they were transplanted to a landscape for two growing seasons to determine the effects of the treatments on trunk survival or growth uniformity in the landscape. The study was replicated in time with containerized `Basham's Party Pink' crapemyrtle liners, but only grown in the field for 1 year. Growth and quality differences were minimal at the end of nursery production for either clone, thus favoring recommendation of whichever treatment would be most economical to produce the desired growth form. However, in the landscape phase, survival of `Sarah's Favorite' crapemyrtle and growth and uniformity of `Basham's Party Pink' crapemyrtle were greater for several growth measures when multiple trunks were produced by training stems of the same plant as opposed to planting multiple liners. Trunk survival was generally good for three or fewer trunks, but significant losses often occurred when the planting units had five trunks, especially when grown from multiple liners. Growth and survival differences among treatments were more pronounced with increasing trunk number and the longer the planting units were in the field (landscape).
Response of Chinese Cabbage Cultivars to Petiole Spotting and Bacterial Soft Rot
Authors: Warner John , Cerkauskas Ray , Zhang Tiequan , Hao Xiuming
Published: December 2018

Nine chinese cabbage (Brassica campestris ssp. pekinensis group var. cephalata) cultivars were evaluated for petiole spotting (gomasho) and bacterial soft rot (caused by Erwinia carotovora ssp. carotovora) in 1999 and fifteen in 2000 and 2001. The cultivars were arranged in a randomized complete block design in a Granby sandy loam soil with six replications in 1999 and three replications in 2000 and 2001, at the Greenhouse and Processing Crops Research Centre, Harrow, Ontario, Canada. Plants were harvested in the fall of each year during two harvest periods, one for early-maturing cultivars, and one for late-maturing cultivars. At harvest, the percent bacterial soft rot, percent marketable heads, plant size, uniformity of harvest maturity, and the mean head weight were determined for each cultivar. The number and weight of spotted leaves was determined by rating (0 to 5 scale) each leaf. Petiole spotting was also rated following storage at 2 °C (36 °F) and 89% ± 5% relative humidiyt for 3 to 4 weeks in 1999 and 2000. `Yuki', `Manoko', and `Summer Top' had lowest losses from bacterial soft rot while `Akala', `Ohken 75', `Spring Flavor', and `Yuki' had low levels of petiole spotting. Cold storage increased the incidence of the spotting disorder for most cultivars.
Herbals: The Connection Between Horticulture and Medicine
Authors: Janick Jules
Published: December 2018

The prehistoric discovery that certain plants cause harm and others have curative powers is the origin of the healing professions and its practitioners (priest, physician, and apothecary), as well as professions devoted to plants (botany and horticulture). The description of plants and their properties and virtues (termed herbals in the 16th century) became an invaluable resource for the physician and apothecary. The earliest medicobotanical treatises date to antiquity. A Sumerian tablet from about 2100 bce (before current era) contains a dozen prescriptions and proscribes plant sources. In China, the Pen T'Sao Ching, assumed to be authored by the legendary Emperor Shen Nung in 2700 bce, but probably written in the first century, contains about 100 herbal remedies. The Ebers Papyrus, a medical treatise from ancient Egypt dates to 1550 bce but contains material from 5-20 centuries earlier. In Greece, the great botanical treatise Enquiry into Plants of Theophrastus, devotes book IX to the medicinal value of herbs. The herbal De Materia Medica by Pedanios Dioscorides of Anazarba, a Roman army physician, written in the year 65, the most famous ever written, was slavishly referred to, copied, and commented on for 1500 years. The great epoch of printed herbals appeared in the 16th century of which the most notable are Das Buch zu Distillieren (1500) by Hieronymus Brunschwig; Herbarum Vivae Eicones (1530, 1532, 1536) by Otto Brunfel; Kreüter Buch (1542) by Hieronymus Bock; De Historias Stirpium (1542) of Leonhart Fuchs; New Herball (1551, 1562, 1568) by William Turner; Commentarii “on Dioscorides” (1544) by Pier Andrea Mattioli; Crôÿdeboeck (1554) by Rembert Dodoens; and the Herball (1597) by John Gerard. Botany and medicine were essentially in step until the 17th century when both arts turned scientific and, at this juncture, botanical works would essentially ignore medicinal uses while medical works were devoid of plant lore. Yet, the medicinal use of herbs continues as an alternate form of medicine and remains popular in various forms to the present day despite the questionable efficacy of many popular herbs and the reliance of many herbal recommendations on superstition and astrology. The fact that most drugs were originally plant-based has encouraged a new look at the medicinal properties of plants.
Dietary Supplements: The New Herbalism
Authors: Craker Lyle E. , Gardner Zoë
Published: December 2018

The passage of the Dietary Supplement Health and Education Act in 1994 made the use of supplements more acceptable in the U.S., increasing demand for botanicals to use in health care and maintenance. These botanicals, primarily medicinal and aromatic plants, currently represent about 25% of the dietary supplement market in the U.S. Although much of the market for botanicals traditionally has been met through collection of plants in the wild, enhanced cultivation of several species will be essential to bring standardized, quality plant materials into the marketplace.
Vegetarianism and Human Health
Authors: Palaniswamy Usha R.
Published: December 2018

Vegetarianism dates back to a time before recorded history and, as many anthropologists believe, most early humans ate primarily plant foods, being more gatherers than hunters. Human diets may be adopted for a variety of reasons, including political, esthetic, moral, environmental and economic concerns, religious beliefs, and a desire to consume a more healthy diet. A major factor influencing the vegetarianism movement in the present time is primarily associated with better health. Epidemiologic data support the association between high intake of vegetables and fruit and low risk of chronic diseases and provide evidence to the profound and long-term health benefits of a primarily vegetarian diet. Vegetables and fruit are rich sources of nutrients, vitamins, minerals, and dietary fiber as well as biologically active nonnutrient compounds that have a complementary and often multiple mechanisms of actions, including antioxidant, anti-inflammatory, hypoglycemic, hypocholesterolemic, and hypolipidemic properties, and mechanisms that stimulate the human immune system. Because of the critical link established between diet and health, consumers have begun to view food as a means of self-care for health promotion and disease prevention. Functional foods are targeted to address specific health concerns, such as high cholesterol or high blood sugar levels, to obtain a desired health benefit. Functional properties identified in a number of plant species have led to a modern day renaissance for the vegetarian movement.
Recognition of Fruit and Vegetables as Healthful: Vitamins and Phytonutrients
Authors: Goldman I.L.
Published: December 2018

Plants are the foundation for a significant part of human medicine and for many of the most widely used drugs designed to prevent, treat, and cure disease. Folkloric information concerning traditional remedies for disease has had inestimable value in establishing familial and cultural linkages. During the 20th century, modern medical science in the U.S. and other developed countries ushered in a new era focused on synthetic medicines. Even though many of these compounds were based on natural compounds found in plants, the drive towards synthetic pharmaceuticals created a knowledge gap concerning the health functionality of plants, crops, and food. Paralleling this development, biochemists and nutritional scientists pioneered the discovery of vitamins during the early decades of the 20th century. This research paved the way for dietary guidelines based on empirical data collected from animal feeding trials and set the stage for the current emphasis on phytonutrients. Three primary stages characterize the use of fruits and vegetable in human health. The first stage concerns the observation that many fruit and vegetable crops were originally domesticated for their medicinal properties. Making their way into the diet for this purpose, fruit and vegetable crops remained on the fringe from a culinary point of view. The second stage began when the role of vitamins became more widely understood, and fruit and vegetable plants were quickly recognized as a rich source of certain vitamins, minerals, and fiber. At this point, they became more than just an afterthought in the diet of most U.S. citizens. Cartoon icons such as Popeye made the case for the health functionality of leafy greens, while parents schooled their children on the virtues of carrots (Daucus carota), broccoli (Brassica oleracea), and green beans (Phaseolus vulgaris). This renaissance resulted in large increases in fresh fruit and vegetable consumption across the country, a trend that continues to this day. The third phase can be characterized by the recognition that fruit and vegetable crops contain compounds that have the potential to influence health beyond nutritional value. These so-called functional foods figure prominently in the dietary recommendations developed during the last decades of the 20th century. In recent years, surveys suggest nearly two-thirds of grocery shoppers purchase food specifically to reduce the risk of, or manage a specific health condition. Evidence abounds that consumers, including Baby Boomers, choose foods for specific health benefits, such as the antioxidant potential of vegetables, suggesting high levels of nutritional literacy. Clinical and in vitro data have, to some degree, supported the claims that certain foods have the potential to deter disease, however much research remains to be conducted in order to definitively answer specific dietary-based questions about food and health.
Aluminum Foil, Aluminium-painted, Plastic, and Degradable Mulches Increase Yields and Decrease Insectvectored Viral Diseases of Vegetables
Authors: Greer Lane , Dole John M.
Published: December 2018

For decades, vegetable growers have used black polyethylene mulch to warm the soil in early spring, reduce weeds, and conserve soil moisture. Use of plastic mulch can increase crop yields and improve fruit quality. This article reviews research performed with plastic, aluminum foil, aluminum-painted, and degradable mulches. Most research focused on the effects of plastic mulches on insects and viruses they vector, and on yields. Aluminum foil and aluminum-painted mulches are effective at repelling insect pests, especially aphids (Aphididae) and thrips (Thripidae). Yields are often higher with black plastic compared to bare ground. Clear plastic is rarely used in the U.S. because it can encourage weed growth, unless a herbicide or fumigant is used underneath. Colored mulches can increase yields and control pests, but color may be less important than brightness of the mulch or contrast with bare soil. New forms of photodegradable mulches eliminate the need to remove and dispose of plastic at the end of the growing season, but have not been widely adapted because they tend to degrade prematurely.
Effect of Plant Growth Retardants on Stem Elongation of Hibiscus Species
Authors: Warner Ryan M. , Erwin John E.
Published: December 2018

One-time spray applications [about 6 mL (0.2 fl oz)] of chlormequat chloride [1000 or 2000 mg·L-1 (ppm)], daminozide (2500 or 5000 mg·L-1), paclobutrazol (20 or 40 mg·L-1) and uniconazole (5 or 10 mg·L-1) varied in efficacy in reducing Hibiscus coccineus (Medic.) Walt., H. radiatus Cav., and H. trionum L. (flower-of-an-hour) stem elongation. Chlormequat chloride inhibited stem elongation of all species, with a 2000 mg·L-1 application reducing stem length of H. coccineus, H. radiatus, and H. trionum by 87%, 42%, and 52%, respectively, compared to untreated plants, 28 d after application. Paclobutrazol also inhibited stem elongation of all species. Uniconazole reduced stem elongation of H. coccineus and H. radiatus, but not H. trionum. Daminozide applied at 5000 mg·L-1 reduced H. radiatus stem elongation only. Growth retardants examined in this study did not delay flowering of H. trionum, the only species that flowered during the experiment. (Chemical names used: ancymidol (α-cyclopropyl-α-(4-methoxyphenol)-5-pyrimidinemethonol), chlormequat chloride(2-chloroethyltrimethylammonium chloride), paclobutrazol ((+)-(R*,R*)-beta((4-chlorophenyl)methyl)-alpha-(1,1-dimethyl)-1H-1,2,4-triazol-1-ethanol), daminozide ([butanedioic acid mono(2,2-dimethylhydrazide)], uniconazol-P ((E)-(+)-(s)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pent-1-ene-3-ol)).
Resistance of Hosta Cultivars to Petiole Rot Caused by Sclerotium rolfsii var. delphinii
Authors: Edmunds Brooke A. , Gleason Mark L. , Wegulo Stephen N.
Published: December 2018

Eighteen cultivars of hosta (Hosta spp.), selected to represent a wide range of size, leaf shape and color, and genetics, were evaluated for reaction to Sclerotium rolfsii var. delphinii in a greenhouse in Ames, Iowa in 2000 and 2001. Bare-root, single-eye plants were planted in 15.2-cm (6-inch) pots in a soil-containing (2000) and soilless (2001) mix and grown in a greenhouse for 3 months. Plants were then inoculated by placing a carrot disk infested with mycelium of S. rolfsii at the base of the plant. Disease severity was assessed weekly for 6 weeks as percent symptomatic petioles. Disease development varied significantly (P < 0.05) among cultivars. Overall, `Lemon Lime', `Munchkin', `Nakaiana', `Platinum Tiara', and `Tardiflora' had the most severe symptoms and `Halcyon' showed the least disease.
Effect of Application Techniques on Abscission Chemical Deposition and Mechanical Harvesting of `Valencia' Oranges
Authors: Farooq Muhammad , Salyani Masoud , Whitney Jodie D.
Published: December 2018

Field experiments were conducted to investigate the effect of sprayer type, airflow rate, and nozzle output on deposition of active ingredient and mechanical harvesting of `Valencia' orange (Citrus sinensis). Fruit detachment force (FDF) and percentage of fruit removal (PFR) by trunk shaker were used as mechanical harvesting parameters. A PowerBlast sprayer discharging radially and a Titan sprayer discharging over the entire canopy were used. The spray mixture contained an abscission chemical (CMN-pyrazole), a surfactant (Kinetic) and a fluorescent tracer (Pyranine-10G). Deposition was determined at three different heights outside and inside of the canopy. With the PowerBlast, higher airflow and lower nozzle output reduced deposition of the active ingredient. The mean FDF of sprayed treatments was less than that of the non-sprayed control but the difference among the four spray treatments was not significant. The lower airflow rate with lower nozzle output had higher PFR than that of the control. With the Titan sprayer, the mean deposition at lower airflow was similar to or higher than the higher airflow. At higher airflow, the lower nozzle output gave higher mean deposition. The Titan sprayer treatments resulted in less FDF than the control. At both airflow rates, the FDF was less at lower nozzle output than at higher nozzle output. The PFR of these treatments were not different from that of control.
A Closed-capture Irrigation Effluent System For Monitoring Large Container Leachate
Authors: Bush Edward W. , Gray Ann L. , Wilson Paul W. , Edling Robert I.
Published: December 2018

Irrigation management is essential in producing quality woody ornamentals and minimizing off-site runoff. The closed-capture effluent device provided an inexpensive method of monitoring effluent in large containers throughout the year with minimal effort. Daily irrigation requirements for `Little Gem' southern magnolia (Magnolia grandifolia) were established throughout an entire growing season. The maximum daily water requirement was approximately 3 gal (11.4 L).
Yield and Quality of Triploid Watermelon Cultivars and Experimental Hybrids Grown in Mississippi
Authors: Cushman Kent E. , Snyder Richard G. , Nagel David H. , Gerard Patrick D.
Published: December 2018

Evaluations of 21 entries (commercial cultivars and breeders' experimental hybrids) of triploid watermelon (Citrullus lanatus) were conducted in northern and central Mississippi during 2000 and 2001. The purpose of this research was to identify high-yielding, medium-sized triploid cultivars with good horticultural characteristics and consumer qualities for commercial production in Mississippi. Most entries were similar to `Tri-X 313' and had red flesh, oval shape, and a mottle stripe rind pattern. SXW 5052, `Triple Crown,' `Crimson Trio,' `SeedWay 4502,' and `Millionaire' produced the highest total marketable yields; however, SXW 5052 is no longer available. `Crimson Trio' produced slightly smaller-sized melons compared to other entries and `SeedWay 4502' produced melons with relatively low soluble solids concentration. Based on total marketable yield, average size of melons, soluble solids concentration, and lack of undesirable characteristics such as hollowheart, black and colored seed, and rind necrosis, `Triple Crown,' `Millionaire,' `Cooperstown,' `Summer Sweet 5244,' and `Crimson Trio' can be recommended as mid- to late-maturing cultivars for commercial production in Mississippi. Based on early marketable yield, and using the same criteria listed above, `Tri-X 313' and `Tri-X Carousel' can be recommended as early-maturing cultivars for commercial production in Mississippi. `Tri-X 313' exhibited only one undesirable trait, producing a relatively high number of black and colored seeds. `Diamond' had high early and total yields, as well as high soluble solids concentration, but it should be recommended only on a trial basis to determine its potential susceptibility to hollowheart.
Vascular Decline in the Oregon Pawpaw Regional Variety Trial
Authors: Postman Joseph D. , Hummer Kim E. , Pomper Kirk W.
Published: December 2018

A pawpaw (Asimina triloba) regional variety trial (PRVT) was established at the U.S. Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR), Corvallis, Ore., in Fall 1995. This orchard was a replicated planting of 28 commercially available varieties or advanced selections from the PawPaw Foundation (PPF; Frankfort, Ky.), with eight replicate trees of each selection grafted onto seedling rootstocks and planted in a randomized block design. Two years after planting, 32 trees had either failed to establish or had died after an initial healthy start. By July 1999, 25% of grafted trees had died due to a vascular wilt-like disease, and 2 years later mortality exceeded 50%. Grafted selections with the lowest symptom severity include 1-7-2, 2-54, 7-90, 8-58, 9-58, `Mitchell', `PA-Golden #1', `Taylor' and `Wilson'. Seedling guard trees were unaffected until July 2000, when six guard trees of 76 died and 10 more were declining. By July 2001, 14 guard trees were dead. No fungi were consistently isolated from declining trees. A number of bacteria were isolated from infected trees, but no specific pathogen has been confirmed as the causal agent. Polymerase chain reaction (PCR) tests for phytoplasmas and for the bacterium Xylella fastidiosa were also negative. Research is ongoing to determine if a bacterial pathogen was the cause of the pawpaw decline in the Oregon PRVT.
Container Production of Pawpaw Seedlings
Authors: Pomper Kirk W. , Layne Desmond R. , Jones Snake C.
Published: December 2018

Pawpaw (Asimina triloba) is a native North American tree that has potential as a new fruit crop or for use in landscapes, but until recently, little information has been available to nurseries on containerized production of this species. Pawpaw seedlings develop a strong taproot with a fragile root system, which can be easily damaged upon digging; therefore, most nurseries propagate trees in containers. Pawpaw seed requires stratification for optimal germination and seed is sensitive to desiccation. The seed also cannot tolerate freezing temperatures [<-15 °C (5.0 °F)]. A well-aerated potting substrate with a high sphagnum peat moss component (>75% by volume), cation exchange capacity, and water holding capacity can be used effectively in container production. Tall containers should be used to accommodate the developing taproot of seedlings. The slow-release fertilizer Osmocote 14-14-14 (14N-6.1P-11.6K) incorporated into Pro-Mix BX potting substrate can be used effectively as the sole fertilizer source at a treatment rate of 2.22 kg·m-3 (3.742 lb/yard3) in containerized pawpaw production. It can also be used at a lower rate of 0.81 kg·m-3 (1.365 lb/yard3) when supplemented with weekly applications of 500 mg·L-1 (ppm) of Peters 20-20-20 (20N-8.78P-16.6K) liquid-feed fertilizer. Bottom heating [32 °C (89.6 °F)] of container-grown pawpaw seedlings results in greater lateral and total root dry weight than in seedlings grown at ambient temperature [24 °C (75.2 °F)], which could increase the rate of establishment of seedlings in the field. Bottom heating of container-grown pawpaw seedlings could decrease both the time to produce a saleable plant and the cost of heating greenhouses. Growth of containerized pawpaw seedlings is enhanced by low to moderate shading with polypropylene shade fabric (28% or 51%) outdoors and low shading (33%) in the greenhouse, in a manner typical of that reported for other shade-preferring plants. Low to moderate shading of pawpaw seedlings grown outdoors greatly increases leaf number, total leaf area, and total plant dry weight compared to nonshaded seedlings, suggesting that commercial nurseries can improve production of containerized pawpaw seedlings using a shading regime outdoors.
Favorable Taste Ratings for Several Pawpaw Products
Authors: Templeton Susan B. , Marlette Martha , Pomper Kirk W. , Jones Snake C.
Published: December 2018

Marketed as a fresh fruit, the pawpaw (Asimina triloba) has a short shelf life, only 2-3 days at room temperature and up to 3 weeks with refrigeration. There is commercial processing potential for pawpaw pulp in juices, ice cream, yogurt, baked goods, and other products. Consumer acceptability of such products needs to be investigated. One hundred and five attendees of the 2nd Annual Pawpaw Field Day at Kentucky State University (KSU), Frankfort, Ky., participated in a tasting of pawpaw products; 56% of tasters were male; 76% were over 40 years of age; 72% of tasters had eaten pawpaw previously. Each item was rated on a scale from 1 = liked it extremely to 7 = disliked it extremely. Pawpaw ice cream was the best-received item (55% of tasters liked it extremely), followed by pawpaw cake with lemon icing, liked extremely by 45%. The pawpaw/grape juice drink was liked extremely by 31% of participants. Three alternative recipes for pawpaw butter were presented; the plain pawpaw butter was liked extremely by 26% of tasters; pawpaw butter prepared with lemon and grape juice was liked extremely by 11%, while the version prepared with orange and lemon was liked extremely by only 8%. Two versions of pawpaw custard were presented. The custard prepared from ripe, mild-fl avored fruit was liked extremely by 42% of tasters, while the custard prepared from mixed under-ripe, over-ripe and bruised fruit was liked extremely by only 16%. Ratings by persons unfamiliar with pawpaw fl avor were significantly lower (P < 0.05) only for the two pawpaw custards; tasters age 40 years or younger gave significantly higher ratings for pawpaw ice cream (P < 0.05) and significantly lower ratings for both pawpaw custards (select, P < 0.05 and mix, P < 0.01) and the pawpaw/grape juice drink (P < 0.05).
ZZ: A Unique Tropical Ornamental Foliage Plant
Authors: Chen Jianjun , Henny Richard J.
Published: December 2018

ZZ (Zamioculcas zamiifolia), a member of the family Araceae, is emerging as an important foliage plant due to its aesthetic appearance, ability to tolerate low light and drought, and resistance to diseases and pests. However, little information is available regarding its propagation, production, and use. This report presents relevant botanical information and results of our four-year evaluation of this plant to the ornamental plant industry.
Adaptation and Market Potential of Jack o' lantern and Miniature Pumpkin Cultivars in Eastern North Carolina
Authors: Stanghellini Michael S. , Schultheis Jonathan R. , Holmes Gerald J.
Published: December 2018

In 1998 and 1999, a total of 27 large-fruited and 15 miniature-fruited pumpkin (Cucurbita pepo) cultivars were evaluated for adaptation to eastern North Carolina grow- ing conditions. Test categories were yield (fruit number and weight); fruit characteristics (shape, rind and stem attributes); and susceptibility to edema (wart-like growths on fruit exterior), foliar diseases, preharvest and postharvest fruit decay, and viruses. Yields of large pumpkins ranged from over 3,200 fruit/acre (7,907 fruit/ha) for `SVT 4613367', `Autumn Gold', and `Gold Standard' to less than 1,000 fruit/acre (2,471 fruit/ha) for `Gold Rush' and `Progold 200'. For miniature pumpkins, over 33,000 fruit/acre (81,542 fruit/ha) were produced by `Touch of Autumn', `Lil' Pump- ke-mon', and `HMX 5682', whereas `Mystic' and `Progold 100' produced less than 7,000 fruit/acre (17,297 fruit/ha). `Gold Rush', `Howden', and `Progold 510' (large), and `EXT 4612297', `Lil' Goblin', and `Lil' Ironsides' (miniature) appeared the most susceptible to foliar diseases. Preharvest fruit decay ranged from 0% for `Howden' and `EXT 4612297' to over 20% for `Lil' Goblin', `Jumping Jack', `Peek-A-Boo', and `Tom Fox'. Virus incidence on fruit and foliage was low on virus-resistant cultivars ('SVT 4613367' and `EXT 4612297'), and ranged from 4% to 74% for nontransgenic cultivars. Virus incidence and/or severity on foliage and fruit were not related. `Early Autumn' (large) and `Touch of Autumn' (miniature) were the most prone to edema. `Aspen' and `Magic Lantern' (large) and `Baby Pam', `Lil' Goblin', and `Spooktacular' (miniature) were the most susceptible to postharvest fruit decay. Fruit characteristics are discussed in relation to marketability and possible consumer appeal to pumpkins.
An interactive online database for the selection of woody ornamental plants
Authors: Lehrer Jonathan M. , Brand Mark H.
Published: December 2018

Web sites such as the University of Connecticut (UConn) Plant Database allow large volumes of information and images to be stored, published and accessed by users for the purpose of informed decision-making. Sorting information on the World Wide Web (Web) can be difficult, especially for novice users and those interested in quick results. The advent of Internet search and retrieval software fosters the creation of interactive decision support systems. The Plant Selector was designed to complement the UConn Plant Database plant encyclopedia by allowing Web site users to generate lists of woody ornamental plants that match specific criteria. On completion of an HTML-based search form by users, a Web-enabled database is searched and lists of matching plants are presented for review. To facilitate analysis of the Plant Selector's efficacy, an online questionnaire was implemented to solicit user feedback. Survey data from 426 responses to the online evaluation tool were analyzed both to understand user demographics and gauge satisfaction with the Plant Selector module. Survey data revealed that most Plant Selector users are between 40 to 65 years of age and homeowners with minimal horticultural experience. A large percentage of Web site visitors (68%) is located across the United States beyond Connecticut and the New England region. The great majority of survey respondents (65%) use this tool to select plants for the home landscape. Most (77%) either agree or strongly agree that the Plant Selector is easy to use and delivers results that are useful (66%), while 70% agree or strongly agree that the categories used by the Plant Selector are sufficient. The survey results in general suggest that Web-based decision support systems may serve useful roles in the field of horticulture education.
Preliminary Estimates of Nitrogen Availability from Liquid Dairy Manure to Potato
Authors: Curless Meghan A. , Kelling Keith A.
Published: December 2018

Within Wisconsin, there is a distinct movement toward dairy herd expansion and consolidation of small farms. These large dairies are considering various land and manure management arrangements with non-livestock farmers, such as potato (Solanum tuberosum) producers to increase their manure management options. This study used a fertilizer equivalence approach to evaluate the availability of nitrogen from dairy manure to potatoes. Nitrogen (N) availability was evaluated in field experiments in 2000 and 2001, conducted in northeast Wisconsin using a moderate and a high liquid dairy manure rate [10,000 and 20,000 gal/acre (93,536 and 187,072 L·ha-1)] compared with results obtained from N fertilizer applied at five rates [0 to 240 lb/acre (269.0 kg·ha-1)]. Availability estimates using the fertilizer equivalence method based on tuber yield, harvested tuber N concentration and uptake, petiole nitrate concentration, and soil nitrate levels resulted in apparent availability of manurial N from 10% to 40%, with an overall average across both years of 29.2%. This level is only slightly less than values typically measured where corn has been used as the test crop. In spite of being more shallow-rooted and perhaps somewhat less efficient in N use it does not appear that adjustments to manurial N availability estimates are warranted when potatoes are grown.
Summary of Temperature Stress Issues in Nursery Containers and Current Methods of Protection
Authors: Mathers Hannah M.
Published: December 2018

Container nurseries are generally more productive than field nurseries because plants can be produced faster and at higher densities. Increasingly, nursery stock is being propagated, grown, and marketed in containers. The prime biological advantage of container stock over bareroot and field-grown balled and burlapped (B&B) stock is that the root system is packaged and protected from transplant or mechanical stress; however, temperature stress limits container production. Plants overwintered in containers suffer greater winter injury than those in the ground because the roots are surrounded by cold, circulating air rather than the insulating environment of the soil. There are several methods for providing protection from cold winter temperatures that are used in the nursery industry; however, all are labor intensive, expensive and vary in effectiveness. Container stock also suffers from elevated summer root zone temperatures. Cultivar differences in the degree of summer injury have been reported. With increasing human population pressures and decreasing availability of fresh water supplies, the need for more water-efficient nursery cultural practices becomes increasingly important. Water and nutrient use efficiency are predominant factors restricting nursery container production. Cultural factors that improve root function and reduce root injury and container heat load are considered key to improving these efficiencies. This paper examines temperature stress issues and the effects of different nursery cultural environments such as conventional overwintering systems, conventional gravel production surfaces, pot-in-pot production, and retractable roof greenhouses.