bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutrient Uptake and Distribution in a Mature `Pinot noir' Vineyard
Authors: Schreiner R. Paul , Scagel Carolyn F. , Baham John
Published: February 2019

The nutrient uptake and distribution patterns for N, P, K, Ca, and Mg were determined in mature (23 to 24 year old), field-grown, rainfed grapevines (Vitis vinifera L. `Pinot noir') growing in a red hill soil in Oregon in 2001 and 2002. Biomass, nutrient concentrations, and nutrient contents of all plant organs, including roots, were determined on 14 sampling dates over 2 years. There was no seasonal change in the standing biomass of primary roots (fine feeder roots), small woody (<4 mm diameter) or large woody (>4 mm diameter) roots. Trunk biomass also did not change during the 2 years, but all other vine organs showed significant seasonal changes in biomass. The rate of N uptake was greatest at bloom, when remobilization from reserves was also high. Nitrogen was also taken up after leaf fall in 2001, but not in 2002, when an early frost occurred before soil moisture recovery by fall rains. Uptake of N, K, and Ca from soil was similar between years, even though canopy demand for N and K was greater in 2002 (significantly larger crop). Phosphorus uptake from soil was lower in 2002 than in 2001, which was most likely due to the drier conditions in 2002. A greater quantity of canopy N, K, and especially P was supplied from stored reserves in the drier 2002 growing season. About 50% of canopy requirements for N and P were remobilized from reserves in the trunk and roots by the time of fruit maturity in 2002. Only 15% of canopy K and <5% of canopy Ca or Mg came from stored reserves in 2002. Our findings indicate that nonirrigated grapevines grown in Oregon acquire nutrients from soil earlier in the growing season and have a greater reliance on stored reserves of N and P than reported in previous studies from other growing regions. Replenishment of nutrient reserves occurred to large extent during the postharvest period. Rainfed vineyards in Oregon may require different nutrient management practices than irrigated vineyards, since low soil moisture may limit summer uptake of P.
Factors Affecting Reductions in Photosynthesis Caused by Applying Horticultural Oil to Grapevine Leaves
Authors: Baudoin Anton , McDonald Sarah Finger , Wolf Tony K.
Published: February 2019

Phytotoxicity of horticultural oil, applied shortly before antifungal sulfur, was evaluated for 23 grape cultivars. Oil application significantly reduced accumulation of soluble solids in berries of 9 of 23 cultivars, but there was no relationship with visible foliar injury. Treatment of leaves of Vitis labrusca `Catawba' with 1.5% JMS Stylet-Oil reduced leaf net photosynthesis (Pn) by 50% to 60% and of Vitis vinifera `Chardonnay' by 20% to 30% 1 day after application. Pn was reduced only when the lower (abaxial) leaf surface was treated; treatment of only the adaxial leaf surface had little effect. The Pn depression in `Catawba' persisted 3 to 4 weeks, whereas reductions in `Chardonnay' persisted less than 2 weeks. The Pn-depressing effect of oil was not significantly ameliorated by real or simulated rainfall, and washing the lower leaf surfaces with water and detergent also had only limited effect. There was no significant difference in Pn depression from oil applications made in the middle of the day (stomata open) compared to application in the evening (stomata closed), or from oil applied at higher versus lower application pressure. The greater sensitivity of `Catawba' than `Chardonnay' to Pn depression by oil may be related to the amount of oil retained by the leaves; the pubescent lower leaf surfaces of `Catawba' retained more than twice as much spray emulsion as did the more glabrous leaves of `Chardonnay'. Visible injury was mild in both cultivars, with small water-soaked lesions developing more commonly on `Chardonnay' than on `Catawba' leaves. Spray oil retention data for additional cultivars suggested that differences in retention can explain a portion of the differences in horticultural oil phytotoxicity.
Effects of Lime Sulfur and Fish Oil on Pollen Tube Growth, Leaf Photosynthesis and Fruit Set in Apple
Authors: McArtney Steven , Palmer John , Davies Sue , Seymour Shona
Published: February 2019

The effect of liquid lime sulfur (LS) and fish oil (FO) application during bloom on leaf photosynthesis (Pn) and pollen tube growth in apple (Malus ×domestica) flowers were investigated in order to determine their mode of action as a bloom thinning agent. LS increased the percentage of flowers with fewer than 10 pollen tubes per flower to more than 64% compared to 5% or less in the control. Pollen tubes were completely absent from 27% to 48% of flowers following LS treatment compared with fewer than 4% of flowers having no pollen tubes on control trees. These data indicate that 30% to 50% of flowers that open on the day of LS application are unlikely to set a fruit due to the complete inhibition of embryo fertilization. Increasing the rate of LS from 0.5% to 4% increased the proportion of flowers with limited pollen tube number in a concentration dependent manner. LS suppressed the rate of light saturated Pn; successive LS sprays during the bloom period had an additive effect on suppression of Pn and fruit set. In one study the reduction in Pn was greatest 12 days after application of LS but Pn recovered by about 19 days after initial treatment. In a second study Pn of primary spur leaves had still not recovered when measured 57 days after the first of three applications. FO had no effect on the number of pollen tubes per flower, but reduced Pn and fruit set by about 10% and 20% respectively. An increase in the proportion of flowers with no pollen tubes, and therefore no embryo development, can account, at least in part, for the thinning response following application of LS to apples during bloom. It is likely that suppression of Pn contributes to the thinning response, although the importance of this mechanism will depend on perturbation of the total carbohydrate supply to developing fruit.
Comparison of an Antitranspirant Spray, a Polyacrylamide Gel, and Wind Protection on Early Growth of Muskmelon
Authors: Hodges Laurie , Daningsih Entin , Brandle James R.
Published: February 2019

Field experiments were conducted over 4 years to evaluate the effects of antitranspirant (Folicote, Aquatrol Inc., Paulsboro, N.J.) and polyacrylamide gel (SuperSorb, Aquatrol Inc., Paulsboro, N.J.) on early growth of transplanted muskmelon grown either protected by tree windbreaks or exposed to seasonal winds. A randomized complete block design (RCBD) with split plot arrangement was used with wind protection (sheltered and exposed) areas as the main treatment and use of an antitranspirant spray or gel dip as subtreatments. Based on destructive harvests in the field, treatments and subtreatments did not affect dry weight or leaf area index in the first 2 years. Specific contrasts, however, showed that gel application significantly increased fresh weight, dry weight, and leaf area index over that of the untreated transplants whereas the spray application tended to reduce these factors during the first 3 weeks after transplanting. Significant differences between gel and spray subtreatments disappeared by 5 weeks after transplanting. Shelterbelts ameliorated crop microclimate thereby enhancing plant growth. Significantly, wind velocity at canopy height was reduced 40% on average and soil temperatures were about 4% warmer in the sheltered plots compared to the exposed plots during the first 5 weeks post-transplant. Muskmelon plants in the sheltered areas grew significantly faster than the plants in the exposed areas in 2 of the 3 years reported, with the 3-year average fresh weight increased by 168% due to wind protection. Overall transplanting success and early growth were enhanced the most by wind protection, followed by the polyacrylamide gel root dip, and least by the antitranspirant foliar spray. We conclude that microclimate modification by wind speed reduction can increase early muskmelon plant growth more consistently than the use of polyacrylamide gel as a root dip at transplanting or the use of an antitranspirant spray. A polyacrylamide gel root dip generally will provide more benefit during early muskmelon growth than the use of an antitranspirant spray.
Effect of a Dynamic Climate on Energy Consumption and Production of Hibiscus rosa-sinensis L. in Greenhouses
Authors: Lund Janni Bjerregaard , Andreassen Andrea , Ottosen Carl-Otto , Aaslyng Jesper Mazanti
Published: February 2019

Production in a dynamic photosynthesis optimized climate (DC) was compared to production in a traditional and more stable climate (TC). Production of a tropical plant species (Hibiscus rosa-sinensis L.) in a DC resulted in between 18% and 63% reduction in energy use, mainly due to lower temperatures and increased use of thermal screens. In high light periods, the average day temperatures (ADT) were virtually the same in the different treatments, while in low light periods both ADT and average night temperature (ANT) were lower in the DC. Differential use of the screens resulted in a higher cumulative light integral in the DC. The number of lateral breaks was either the same or higher in the DC. Dry weight at the end of the production period was not significantly different in six of the seven experiments, and in five out of seven replications, plants grown in the DC were shorter than plants in the TC. Production periods between 10 days shorter and 21 days longer, for the DC compared to the TC, could not be explained by temperature integration alone. In the DC, a high positive DIF (difference between ADT and ANT) does not seem to increase elongation growth. The study illustrates that it is possible to produce a heat-demanding plant and save energy using a DC.
Effects of Low Relative Humidity and Illumination on Leaf Water Status of Cucumber Seedlings and Growth of Harvested Cuttings
Authors: Shibuya Toshio , Terakura Ryoko , Kitaya Yoshiaki , Kiyota Makoto
Published: February 2019

Application of a low-relative-humidity treatment (LHT) to seedlings can reduce water stress on cuttings harvested from the seedlings, after the cuttings are planted. Effects of illumination during LHT and LHT duration on leaf water potential and leaf conductance in cucumber (Cucumis sativus L.) seedlings used as the model plant material and on growth of harvested cuttings were investigated to determine optimal LHT conditions. The seedlings received LHT for 12 or 24 h in a lighted or dark growth chamber at air temperatures of 28 to 31 °C and relative humidity of 12% to 25%. Cuttings including a foliage leaf and two cotyledons were harvested by cutting the hypocotyl of the seedlings immediately after the treatment, and then the cuttings were planted in vermiculite medium. Four days after planting, the total fresh weight of the cuttings from seedlings that had received LHT in the lighted chamber was 2.2 times that of cuttings from seedlings that had not received LHT, whereas the total fresh weight of those that had received LHT in the dark increased by 1.3 to 1.8 times. Significant effects of illumination during LHT were also observed in the transpiration rate and growth of the cuttings, harvested following the treatment, after they were planted. By varying LHT duration, it was also found that leaf water potential and leaf conductance of the seedlings decreased as LHT duration increased up to 18 h. Thus, illumination during LHT increased the growth of cuttings taken following the treatment, and optimal treatment duration of around 18 h was estimated from the seedlings' leaf conductance and leaf water potential.
Potassium Starvation Increases Stomatal Conductance in Olive Trees
Authors: Arquero Octavio , Barranco Diego , Benlloch Manuel
Published: February 2019

The effects of potassium (K) status and water availability in the growth medium on growth, water content, water-use efficiency and stomatal conductance was studied in mist-rooted `Chemlali de Sfax' olive (Olea europaea L.) cuttings grown in a perlite substrate. Potassium starvation produced dehydration of all parts of the plant, reduced shoot growth and water-use efficiency. By contrast, K starvation enhanced stomatal conductance in well-irrigated plants and, even more, in water-stressed plants. These results suggest that moderate K deficiency in olives may impair the plant's ability to regulate stomatal closure; this may account for the dehydration observed in K-starved plants, particularly in situations of water stress. This result is of great importance for agricultural practices of this crop, because K status, which may not be considered deficient, can cause disorders in olive trees.
Fertilization Rate and Irrigation Scheduling in the Nursery Influence Growth, Insect Performance, and Stress Tolerance of `Sutyzam' Crabapple in the Landscape
Authors: Lloyd John E. , Herms Daniel A. , Rose Mary Ann , Van Wagoner Jennifer
Published: February 2019

The objective of this study was to determine if fertilization and irrigation practices in the nursery affect plant growth and stress resistance following outplanting in the landscape. Flowering crabapple (Malus) `Sutyzam', grown in containers under factorial combinations of two irrigations schedules (containers irrigated at 25% or 50% container capacity) and three rates of fertilization (N at 50, 200, 350 mg·L–1) in a nursery in 1997 were outplanted in a low maintenance landscape in 1998. Trees from the high fertility regime grew faster in the landscape the year of transplant. Tree growth in the landscape was positively correlated with N concentration in plants in the nursery and negatively correlated with concentrations of phenolics in the foliage in the landscape. However, the trees showing the greatest amount of diameter growth had the lowest concentrations of foliar phenolics. Trees with low concentrations of phenolics also exhibited a greater potential for herbivory by larvae of the eastern tent caterpillar, gypsy moth, and white-marked tussock moth. Additionally, trees exhibiting rapid growth in the landscape also had reduced photosynthesis during summer drought compared to slower growing trees, suggesting a reduced drought tolerance in the landscape. Differences in growth and stress resistance did not carry beyond the year of transplant. Our results illustrate that irrigation and fertilization methods in the nursery can influence growth post transplant, however fertilization also appears to have a significant impact on stress resistance traits of the trees. These impacts from the nursery production methods had no effect after plants had acclimated to the conditions in the landscape during the year following transplant.
Self-compatible Seedlings of the Cutleaf Hazelnut
Authors: Mehlenbacher Shawn A. , Smith David C.
Published: February 2019

The cutleaf hazelnut [Corylus avellana L. f. heterophylla (Loud.) Rehder] is an ornamental form with strongly dissected leaf morphology. Its stigmas express incompatibility allele S20 but none of the other 25 S-alleles was detected with fluorescence microscopy. Three seedlings from a cross of the cutleaf hazelnut and VR6-28 lacked S20 and were investigated further. Each expressed an allele from the parent VR6-28 (S2 S26), S26 in OSU 562.031 and OSU 562.048 and S2 in OSU 562.049. S2 and S26 are low in the dominance hierarchy, so we expected the new allele from the cutleaf hazelnut to be expressed in their pollen. Unexpectedly, fluorescence microscopy showed that pollen of all three selections was compatible on their cutleaf parent and on each other, and furthermore, self-pollinations showed the excellent germination and long parallel tubes in the styles that are typical of a compatible pollination. Controlled self- and cross-pollinations in the field verified the self-compatibility of two selections. Cluster set for self-pollinations was very high (75-90%) and within the range observed for compatible cross-pollinations. Furthermore, the frequency of blank nuts was low (<10%). The second allele in the cutleaf hazelnut is designated S28, and its presence in seedlings of `Cutleaf' is indicated by the absence of S20. Controlled pollinations in the field also showed that selection OSU 562.069 (S2 S28) from the cross `Cutleaf' × `Redleaf #3' was self-compatible. Fluorescence microscopy showed that two additional seedlings were self-incompatible [OSU 367.052 (S1 S28) and OSU 367.076 (S6 S28)] while a third [OSU 706.071 (S9 S28)] was self-compatible. Self-compatibility may be limited to genotypes that combine S28 with a second allele that is low in the dominance hierarchy.
DEVELOPMENT OF A WHITE-FLOWERED, COLD-HARDY ALSTROEMERIA
Authors: Kollman Elizabeth , Bridgen Mark
Published: February 2019

Alstroemeria, the Inca lily or lily-of-the-Incas, is becoming a popular garden plant in the United States. In past years, the primary interest in Alstroemeria has been for its cut flowers. However, recent cold-hardy introductions (USDA hardiness zone 5) have expanded the interest of this colorful plant as a garden perennial throughout the U.S. Previously, garden interests were restricted to warmer zones in the southern United States where Alstroemeria could over-winter. This research describes a breeding procedure which has been used with the objective to develop a cold-hardy, white flowered Alstroemeria. The interspecific hybrids were bred with the use of in ovulo embryo rescue. Reciprocal crosses were made between several white-flowered cultivars and the cold hardy Chilean species, Alstroemeria aurea during the summers of 2004 and 2005. Ovaries were collected 10–23 days after hand pollination and their ovules were aseptically excised. Ovules were placed in vitro on 25% Murashige and Skoog (MS) medium under dark conditions until germination. Three weeks after germination they were then placed on 100% MS medium, and subcultured every three to four weeks thereafter until they were large enough for rooting. After rooting and acclimation, plants were transferred to the greenhouse. Successful hybrids that were produced in 2004 were evaluated under greenhouse and field trials during 2005. Data on the flower color for each of the hybrids were recorded, as well as certain morphological characteristics that can indicate cold-hardiness. Hybrid plants are being overwintered outside in Ithaca, N.Y. (USDA zone 5), and Riverhead, N.Y. (USDA zone 7), during the next several years for a more accurate assessment of cold-hardiness. Self pollinations and reciprocal crosses with the white-flowered parent were performed on the F1 generation in the summer and fall of 2005 in order to determine segregating characteristics. Few ovules were obtained from F1 generation crosses. Successful F2generation plants are being grown in vitro and will be transferred to the greenhouse where flower color will be noted. Root squashes and pollen staining were completed to determine ploidy levels and assess male sterility of the F1 generation.
SEVERE CUTBACK OF STOCK PLANT INFLUENCES ROOTING IN SHOOT OF QUERCUS BICOLOR AND QUERCUS MACROCARPA
Authors: Amissah Naalamle , Bassuk Nina
Published: February 2019

Two experiments were conducted to determine the effect of severe stock plant cutback on rooting in two oak species Quercus bicolor and Quercus macrocarpa using two propagation systems, layering and cuttings. In experiment 1, field grown plants were either cutback leaving a 0.04 m (1.6 in.) stump above soil level or left intact (not cutback) ≈1.7 m (66.9 inches) tall. Shoots arising from cutback treatments and intact plants were layered using a field layering technique and air layering respectively. Results showed significantly higher (p < 0.01) rooting percentages in layered propagules arising from severely cutback plants in both species [≈77% in Quercus bicolor and ≈70% inQuercus macrocarpa] compared with air layered shoots arising from intact plants [1% in Quercus bicolor and 0% in Quercus macrocarpa]. In experiment 2, shoots arising from three stock plant heights (severely cutback 0.04 m, cutback 1 m and intact ≈1.7 m plants) were either etiolated or grown in full light and cuttings rooted in a perlite medium under mist. Of the two species studied, propagule position was found to have no significant effect on rooting in Quercus macrocarpa cuttings, but significantly (p < 0.0001) influenced rooting in Quercus bicolor. Rooting was highest 59.3% in cuttings taken from cutback-etiolated stock plants. Comparing just the three cutback levels, rooting was highest (45.2%) in cuttings arising from 0.04 m stumps followed by those from 1 m stumps 7.5% and lastly intact plants 3.8%. The best rooting results were observed in shoots arising from severely cutback stock plants (0.04 m) using the field layering technique.
THE NAUTURE OF CONFLICT IN PUBLIC GARDENS
Authors: Stephens Matt , Denhardt Kathryn , Flynn James , Lyons Robert , Swasey James
Published: February 2019

Public gardens are complex, multi-faceted, diverse organizations that execute a broad scope of tasks including fundraising, educational programming, marketing, public relations, and horticultural research. This broad scope of work creates numerous challenges for these institutions. One of which is conflict between front-line and administrative staffs. The goal of this research is to help explain why conflict between front-line and administrative staffs exists in public gardens. The research found no existing research on the topic of conflict in botanic gardens, but some in other industries. The research was a mixed methods design, including two case studies at separate public gardens and an online questionnaire. Both case studies consisted of separate focus groups and individual interviews with staff at different levels of the organization. Questionnaire results also came from various personnel levels (front-line and administrative) of public gardens. Once final data collection occurred, they were coded into similar categories outlined by the Malcolm Baldridge Standards, an internationally recognized assessment tool for excellence. Early analysis of the data indicates that conflict occurs due to a lack of: a clear mission and vision, effective communication, and empowerment within the organization.
DEVELOPING AN INITIAL PLAN FOR A CENTER IN PUBLIC HORTICULTURE AT THE UNIVERSITY OF DELAWARE
Authors: Moydell Edward , Lyons Robert , Morgan Robin , Roberts Frederick , Swasey James , Rudyj Erich
Published: February 2019

Universities are attempting to enhance the quality of their academic and research endeavors as competition increases for students, faculty, and funding. To further its mission of providing excellence in education, research, and extension, the University of Delaware (UD) has created a number of Centers and Institutes devoted to providing leadership to a particular field of study. Because of its unique location in the “hotbed of public horticulture,” UD is interested in establishing an interdisciplinary Center in Public Horticulture. The objective of this study was to create an initial plan for a Center in Public Horticulture at UD outlining its mission, goals, objectives, structure, and function. The plan resulted from an internal environmental assessment of the Plant and Soil Sciences Department at UD, an external environmental assessment of the field of public horticulture, and an analysis of existing Centers and Institutes at UD. This qualitative study utilized surveys, interviews, and focus groups with selected internal and external stakeholders from academia, the green industry, government, and public gardens. Internal stakeholders, in the resulting data, emphasized the Center's role in engaging undergraduate and graduate students and conducting relevant research. External stakeholders indicated that the Center may also focus on providing continuing education or certification programs to public horticulture professionals. The research regarding existing Centers and Institutes produced a variety of recommendations regarding the Center's structure, governance, funding, research activities, and partnerships and collaborations.
THE EFFECT OF TEMPERATURE AND PHOTOPERIOD ON THE LEAF SENESCENCE AND PARTITIONING OF ASTILBE AND PAEONIA
Authors: Lubag-Arquiza Amihan M. , Wien Hans C.
Published: February 2019

The effect of temperature and photoperiod on leaf senescence and partitioning were studied in Fall 2004 using Astilbe simplicifolia `praecox alba' and Paeonia hybrid `Barrington Belle' and Fall 2005 using Paeonia Paula Fay and Astilbe chinensis ×purpurea. Bare root divisions and crowns were potted and grown outdoors during the spring and summer. Plants were treated to either Ithaca fall outdoor and controlled warm (70–60 °F) environment under normal daylength (about 12 hours) or longday (LD15 hours in 2004 and 16 hours in 2005). The chlorophyll readings and senescing leaves were significantly affected by treatments in the two plants in 2004. There was no significant difference in the change in the total dry biomass in Paeonia hybrid `Barrington Belle' grown under different treatments but the number of large buds was highest in those grown at 70–60 °F at LD. Higher total plant biomass was observed over-all in Astilbe simplicifolia `praecox alba' in warmer greenhouse environment and under LD. The effect of photoperiod and its interaction with temperature were significant in weights of Astilbe simplicifolia `praecox alba' roots. Greenhouse grown plants had higher bud numbers compared to outdoor-grown plants. In 2005, Astilbe chinensis ×purpurea in the greenhouse under LD had more shoots and large buds than the other treatments. Senescing leaf and chlorophyll reading was affected by temperature and photoperiod and its interaction. Paeonia Paula Fay under LD outdoors had more large buds than those under natural photoperiod, but is similar in effect to those in the greenhouse. Results may be used to improve propagule quality, adjust crop production cycle and cultivation in different climate.
DELAYED 1-MCP APPLICATION EFFECT ON POSTHARVEST FIRMNESS AND SCALD CONTROL OF MCINTOSH AND CORTLAND APPLES
Authors: Moran R.E.
Published: February 2019

The objective was to test the efficacy of 1-MCP when applied at 1, 4, 7, or 10 days after harvest. At harvest, internal ethylene (IEC) was undetectable in most fruit. There was a large increase in concentration at 7 days after harvest and an additional increased at 10 days in `McIntosh'. In Cortland, IEC was very low or undetectable until 10 days after harvest. After 4 months in CA storage, firmness of untreated `McIntosh' fell below 53 N. 1-MCP applied 1 day after harvest maintained firmness more than later applications. Application at 4–10 days was also effective with little difference between the three dates. 1-MCP was most effective on `Cortland' when applied 1–7 days after harvest. At 10 days, there was a loss of efficacy in maintaining firmness. Similar results occurred after 7 months of CA storage. Superficial scald of `McIntosh' was very mild with <1% of the fruit being affected after 220 days storage and 7 days at 20 °C. Untreated `Cortland' fruit had the greatest incidence of scald with most of the fruit being affected by 200 days. 1-MCP was not effective in preventing scald in `Cortland'.
THE EFFECT OF FLOOD WATER TEMPERATURE ON CRANBERRY UPRIGHTS AND ROOTS DURING SPRING AND FALL FLOODS
Authors: Vanden Heuvel Justine
Published: February 2019

Cranberry bogs are flooded for several purposes during the growing season, including pest control and harvest. A spring `late water' and a fall `harvest' flood were simulated on potted cranberry uprights (`Stevens'). The `late water' flood is a 1-month flood held on some Massachusetts bogs from mid-April to mid-May. The flood was simulated at 11 and 21 °C. Over the course of the 1-month flood, total non-structural carbohydrate concentration (TNSC) of the upright tissue decreased by 13% and 46% in the 11 and 21 °C treatments, respectively. Root TNSC was not affected by flooding in the 11 °C treatment, but was reduced by 39% in the 21 °C treatment. In the 1-week `harvest' flood simulated at 12 and 20 °C, TNSC of the upright tissue decreased by 47% and 59% in the 12 and 20 °C treatments, respectively. Root TNSC was reduced by 22% in the 12 °C flood, and by 41% in the 20 °C flood. Two weeks following removal from the 1-month `late water' flood, uprights in the 11 °C treatment contained 9% more TNSC than uprights in the 21 °C treatment, while root TNSC from the two treatments was similar. No treatment differences were evident in the uprights or roots of the vines subjected to the `late water' flood by harvest. Two weeks following removal from the 1-week `harvest' flood, uprights in the 12 °C treatment contained 20% more TNSC than uprights in the 20 °C treatment, while roots of vines in the 12 °C flood contained 17% more TNSC compared to vines in the 20 °C flood. Vines which were negatively impacted by the warmer `harvest' flood treatment likely had reduced energy available for winter survival, spring growth and fruit production.
PHOSPHORUS EXPORT FROM CRANBERRY BOGS IS AFFECTED BY FERTILIZER P APPLICATION AND WATER MANAGEMENT
Authors: DeMoranville Carolyn , Howes Brian , White David , Shumaker Daniel
Published: February 2019

Although cranberry production typically requires a low fertilization rate compared to many crops, bog waters are generally discharged through surface water flow directly to streams, ponds or lakes and indirectly to coastal waters. Since discharge is primarily to fresh water bodies, and since such waters are generally phosphorus-limited, P is the fertilizer element of most environmental concern in Massachusetts cranberry production. This study was designed to determine how much P enters and leaves cranberry bog systems on an annual basis, what activities contribute to nutrient releases, and what management changes can reduce P discharges. On a total budget basis, including fertilizer applications as inputs and crop and other biomass (leaves) removal as outputs, the bogs were generally net importers of total N and total P. However, total P in outgoing waters was greater than that in source water. Net TP fluvial output averaged 2.08 kg·ha–1·yr–1 in 2002 (range 0.01 to 4.15); 1.66 kg·ha–1·yr–1 in 2003 (range –0.63 to 3.62) and 1.22 kg·ha–1·yr–1 in 2004 (range –1.24 to 4.30). The primary path of nutrient discharge from the bogs was through surface water. Flooding events were the primary source of total P output from the cranberry bogs. Gross total P export from the cranberry bogs was within the range of that for other reported agricultural land uses but greater than that for forested lands. When fertilizer P input was reduced (20% to 35%) at cranberry bog sites for two consecutive seasons, crop yield was not adversely affected and P discharge was reduced compared to that in the initial (prereduction) year.
INTERACTION OF HARVEST TIME AND STORAGE ON ATTRIBUTES OF EATING QUALITY IN ACORN SQUASH
Authors: Loy J. Brent
Published: February 2019

Premature harvest of acorn squash is a widespread problem because fruits reach maximum size and optimum color within 20 days after pollination (DAP), well before peak dry matter and sugar content occur. The present study was conducted to determine the relationship between harvest date and physiological factors affecting eating quality in Cucurbita pepo L. squash. In the summer of 2005, C. pepo squash cultivars were evaluated at three harvest dates, 25, 35, and 45 days after pollination (DAP), with or without a 10-day storage period at 21 °C. Four F1 hybrid cultivars carrying powdery mildew tolerance (PMT) were evaluated: a semi-bush, commercial acorn cultivar (`Tip Top'), a high quality experimental acorn, bush hybrid (NH1634), and two sweet dumpling-type, semi-bush hybrids (NH1635 and 1636). Data were collected on mesocarp DW, oBrix (soluble solids), and partitioning of biomass between mesocarp tissue and developing embryos during storage. Peak DWs of 20% to 21% occurred at 25 DAP in NH1634, 1635 and 1636, and at 35 DAP in Tip Top (19.5 %). At 25 DAP, Brix was low (means of 5.9 to 7.2) across all cultivars. With harvest at 25 DAP plus 10 days storage, oBrix was low in Tip Top (7.1), but was higher than 10 in NH1634 and NH1636. Brix reached near maximum (13 to 15) at 45 DAP in NH1634, 1635 and 1636, and at 55 DAP in Tip Top (12). Embryos were small (DW = 8 to 19 mg) at 25 DAP and grew fairly linearly to a maximum at 55 DAP. Mean embryo DW at 55 DAP was 87.5 mg for Tip Top, 76.9 mg for NH1636, 57.1 mg for NH1634, and 28.5 mg for NH1635. The proportion of total fruit biomass expressed as energy equivalents (kJoules) allocated to embryos in mature fruit (45 DAP + 10 days storage) was 11.8% in NH1635, 18.7% in NH1634, 27.4% in Tip Top, and 30.2% in NH1636. Reallocation of assimilates from mesocarp tissue to developing embryos was a major contributing factor, along with respiration, to a reduction in mesocarp dry matter during storage.
ADVENTITIOUS SHOOT PROPAGATION AND CULTURAL INPUTS ON NURSERY PRODUCTION OF A PRIMOCANE-FRUITING BLACKBERRY SELECTION
Authors: Dennis Kimberley , Clark John R. , Robbins James A.
Published: February 2019

Studies were conducted from January to November of 2005 to determine the effect of root-cutting length on adventitious shoot yield and the management practices necessary to produce nursery-quality blackberry plants. The first portion of the study measured the average number of shoots produced from 7.6 and 15.2 cm long root cuttings of APF-44 blackberry—a primocane-fruiting clone (not available in commerce) from the University of Arkansas breeding program. Cuttings were forced in a shallow bin containing soilless potting media. The average number of shoots per root cutting from 7.6- and 15.2-cm-long root cuttings averaged 1.6 and 2.7 shoots per root cutting, respectively. Rooting percentage of shoots was near 100% regardless of root cutting length and produced rooted plants of equal quality. The latter part of the study included various treatments on the rooted shoots that might affect the productivity and quality of the final product intended for nursery sales in early fall. With the aim of producing a flowering/fruiting shrub by late September, three treatments were applied: pot dimension, fertilizer rate, and shoot tipping. Fertilizer rate had the greatest impact of all treatments. Above normal summer/fall temperatures may explain lack of fruiting on APF-44 blackberries, but the dimension and size of some plants provided a portion of the intended aesthetic.
SELECTIVE BROADLEAF WEED CONTROL IN GROUNDCOVERS
Authors: Walsworth Christina , Bush Edward , Strahan Ronald , Gray Ann
Published: February 2019

Selective broadleaf weed control is a major economic issue facing commercial landscapers and homeowners alike. Minimal selective post-emergent weed research has been successful in controlling landscape weeds. The objectives of this experiment were to determine the efficacy of seven selective broadleaf herbicides [nicosulfuron (0.66 oz/acre), flumioxazin (8 oz/acre), penoxsulam (2.3 fl oz/acre), bensulfuron (1.66 oz/acre), glyphosate (1% by volume), sulfentrazone (8 fl oz/acre), trifloxysulfuron (0.56 oz/acre) and the control] and to determine the ornamental phytotoxicity on three groundcover species (Liriope muscari, Ophiopogon japonicus, and Trachelospermum asiaticum). A RCBD design was used with five blocks. Each block was split establishing either mulched or bare soil plots (nonmulched). The ground-covers were established three months before herbicide application. On 29 June 2005, four weed species were evenly seeded into the blocks with one hundred seeds each of Sesbania exaltata, Ipomea hederacea, Amaranthus retroflexus, and Euphorbia maculata. Herbicides were applied using a CO2 backpack type sprayer on 6 Sept. 2005. Plant and weed control data were taken to evaluate phytotoxicity and efficacy at 0, 1, 7, 14, and 28 DAT. On 27 Oct. 2005, weeds were harvested from each plot and dried for a minimum of 48 h and weighed. No significant differences in phytotoxicity were observed on either Liriope muscari or Trachelospermum asiaticum. However, there was a significant increase in phytotoxicity exhibited by the Ophiopogon japonicus treated with sulfentrazone compared to all of the other herbicides. Glyphosate demonstrated the best overall control of all broadleaf weeds except Sesbania, while trifloxysulfuron showed the best control of Sesbania. There were no significant differences in herbicide efficacy between the mulched and nonmulched plots. Further research is being done to measure the effects of herbicide efficacy and phytotoxicity in 2006.
USING A BILINGUAL GAPS AND HAND-WASHING DVD TO TRAIN FRESH PRODUCE FIELD AND PACKINGHOUSE WORKERS
Authors: Sanders D. C. , Reyes L. M. , Osborne D. J. , Ward D. R. , Blackwelder D. E.
Published: February 2019

The Southeastern Fresh Produce Food Safety Training Program has been training extension agents across the southeastern U.S. since 2000. This program has utilized a variety of methods including group case study to enhance learning and promote team work. Multistate trainings have fostered collaboration between states and institutions. One goal of the program was to produce a method for agents to provide training that was repeatable and easy to implement. As a result, two videos were produced for use in training field and packinghouse workers. These videos were an English language good agricultural practices (GAPs) video entitled Bridging the GAPs: From the Farm to the Table and a Spanish language hand-washing video entitled ¡Lave sus Manos: Por Los Niños! This program has been very effective, but has faced challenges due to language barriers. Many field and packinghouse crews were mixed in terms of language with some crew members speaking only English while others spoke only Spanish. As a result, Spanish speakers were unable to access the information in the good agricultural practices video while English speakers were unable to access information in the hand-washing video. The solution was to produce a bilingual training aid that included both sets of information and has been compiled into a DVD containing the footage of both of the original videos in both languages. For the Spanish version of the GAPs video and the English of the hand-washing video, the audio of the video's original language was left at a low sound level and the audio of the alternate language was added. These DVDs are currently being distributed to extension programs in all of the cooperating states with the aim of reaching growers who want to start a food safety plan.
USING A CONSUMER HERB GARDENING STUDY TO DETERMINE PROGRAM AND PUBLICATION NEEDS
Authors: Kelly Lelia S. , Newman Michael , Hood Ken
Published: February 2019

Extension specialists are charged with developing programs and publications based on audience needs. In consumer horticulture it can be difficult to gauge the needs that are client driven rather than extension driven. This study was an attempt to gather herb gardening information directly from gardeners. In total, 188 Master Gardeners completed a questionnaire that included questions ranging from the use of OTC herbal supplements to preservation methods. Analysis of data indicated that, based on sex, age or household income, participants were not different in most of their responses. When asked to check all the reasons they grew herbs, the top two were culinary and ornamental. Thirty-seven percent took OTC herbal supplements and 35% of those did so without their doctor's knowledge. Twelve percent indicated they treated themselves or family members for a medical condition using homegrown herbs. There was a significant difference between male and female when answering this question. Thirty-two percent of the male sample compared to just 9% of the females provided this home treatment. Primary propagation method was transplants. Pesticide use was minimal with only 2% using these. Easiest herbs to grow were rosemary, mint and basil in that order. Most popular herbs for cooking were basil, rosemary and chives. Top preservation method was drying, but freezing, vinegars and even herbal liquors were popular methods. Study results indicate that information dealing with cooking or ornamental uses of herbs would be popular. New ideas for old favorites as well as including new herbal cultivars would be useful. Nutritive and health issues, in particular involving herbal supplements, would be an opportunity for collaborative work with health and nutrition specialists.
CREATION OF A VIRTUAL MS NONTHESIS PROGRAM IN HORTICULTURE
Authors: McKenney Cynthia
Published: February 2019

An on-line MS nonthesis horticulture program has recently been developed by Texas Tech University. The profile of the average student participating in the program does not match the current national demographics of a 25 to 27 year old female. Rather, this distance student profile is 40- to 50-year-old male who owns his own horticultural business or serves in a horticultural management position for a city. These distance students generally excel academically as they have waited for years to pursue an advanced degree. They also communicate effectively and frequently via e-mail or course platform outlets. The distance MS students complete a traditional 36-hour program, have a graduate committee of both internal and external faculty members and stand for an oral defense. Enrollment has increased an average of 50% each semester the program has been offered. The primary challenge incurred since the inception of the program has been sustained rapid growth. While the MS nonthesis program has grown, the BS enrollment has increased almost as rapidly.
OPPORTUNITIES FOR EXPORTING ORNAMENTAL PLANTS FROM MIAMI-DADE COUNTY TO THE CARIBBEAN
Authors: Rafie A. R. , Garofalo Joe
Published: February 2019

In Miami-Dade County, Fla., there are 1,240 registered nurseries, growing plants in 14,000 acres, making it the state's leading nursery crop producer. This industry provides 18,000 nursery related jobs and in 2000 had an estimated total value of $790 million. Like many other agricultural industries in Florida, the nursery industry has become very competitive; as a result, many growers are searching for new marketing opportunities. The Caribbean region consists of 28 nations with a population of 21 million. This region is considered one of the most dependent on agricultural imports. In 2004, United State agricultural exports to the Caribbean reached a total value of $1.9 billion, of which $9 million was nursery plant product. Due to proximity of many of the Caribbean countries and cheap transportation costs, the United State is essentially trading in its own backyard. To strengthen the export knowledge of local nursery growers, a partnership was created among the Southern U.S. Trade Association (SUSTA), the USDA's Caribbean Basin Agricultural Trade Office (CBATO), Miami–Dade College, and the University of Florida/Miami–Dade County Cooperative Extension Service. Two different workshop series were offered to train selected nursery managers about the export essentials. As a result of this partnership, 21 nursery growers were able to complete the program, 57% of the participants had exported in the past to the Caribbean and 43% are now starting to export.
POLICIES FOR THE PROPRIETARY RELEASE, DISTRIBUTION AND SALE OF SMALL FRUIT CULTIVARS AND GERMPLASM BY LAND GRANT UNIVERSITIES IN THE SOUTHERN REGION OF THE U.S.
Authors: Ballington James R.
Published: February 2019

Public funding for land-grant university plant breeding programs has declined to the point that alternative sources of funding have had to be identified in order for these programs to continue. Small fruit breeding programs at land-grant universities in the southern region of the U.S. now derive their support for day to day operations from a number of alternative funding sources including commodity organizations and research foundations. Royalty income generated from sale of plants of patented cultivars has also become a significant source of support for essentially all land grant programs. In addition, cooperative agreements and contracts with partners in private industry play a prominent role in support for several programs, and these will likely increase significantly in the near future. At present, U.S. plant patents are generally applied for upon the release of cultivars from small fruit breeding programs at land grant universities in the southern region, with some move toward trademarking. Releases are generally nonexclusive within the region, and either exclusive or nonexclusive outside the region. The use of germplasm from other breeding programs usually carries with it the expectation of mutual exchange and use of germplasm and/or sharing of royalty income from cultivars derived from such germplasm.
ANTIOXIDANT ACTIVITY AND PHENOLIC COMPOSITION CHANGES IN SWEETPOTATO ROOT AND LEAF TISSUE DURING DEVELOPMENT
Authors: Padda M.S. , Picha D.H.
Published: February 2019

Antioxidant activity and phenolic content in sweetpotato root and leaf tissues were quantified at different developmental stages. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical method was used to measure antioxidant activity and total phenolic content was quantified by spectrophotometry using Folin-Denis reagent. Individual phenolic acids were quantified using reversed phase high performance liquid chromatography. Antioxidant activity and phenolic content decreased with root development and leaf maturity. Roots at the initial stages of development (about 4 g root weight) had a higher antioxidant activity and phenolic content compared to fully developed roots. Phenolic content in fully developed roots was significantly higher in the cortex tissue than internal pith tissue. The highest total phenolic content and antioxidant activity was found in cortex tissue at the initial stage of development (10.3 mg chlorogenic acid eq/g dry tissue weight and 9.7 mg Trolox eq/gdry tissue weight, respectively). Sweetpotato leaves had a significantly higher phenolic content and antioxidant activity than roots. Immature unfolded leaves had the highest total phenolic content (88.5 mg chlorogenic acid eq/g dry tissue weight) and antioxidant activity (99.6 mg Trolox eq/g dry tissue weight). Chlorogenic acid was the major phenolic acid in root and leaf tissues with the exception of young immature leaves in which the predominant phenolic acid was 3,5-dicaffeoylquinic acid.
EFFECT OF WASHING AND CUTTING ON NO3-N AND K SAP CONCENTRATIONS ON VEGETABLE PETIOLES
Authors: Studstill David , Farneselli Michela , Simonne Eric , Hochmuth Bob
Published: February 2019

Petiole sap testing using ion-specific electrodes is a simple method that can be used to guide in-season applications of N and K to vegetable crops. This method requires petiole sampling and sap extraction using a sap press. Because some vegetables are grown with foliar applications of N and/or K and because some crops have large petioles, petioles may need to be washed and/or cut before being pressed. Because limited information is available on the effect of washing/cutting on sap testing results, muskmelon, bell pepper and tomato petioles were used to test if washing/cutting reduced NO3-N and K concentrations and changed the subsequent interpretation of plant nutritional status. Washing for 30, 60, or 120 seconds in distilled water and cutting petioles before or after washing significantly reduced sap concentrations (p = 0.01 and p = 0.04 for NO3-N and K, respectively) in 7 of 12 tests when compared to the control method (petioles cut and not washed). The average concentration reductions between the control and the lowest value among all the washing/cutting treatments were 30% for NO3-N and 19% for K. These losses due to washing/cutting are likely to change the diagnosis of nutritional status from “sufficient” to “less than sufficient” and therefore may suggest the need for unnecessary fertilizer applications.