bluuebunny/crossref_metadata_2025 huggingface dataset:
639 Tomato Response to Residual Compost and Fertilizers
Authors: Csizinszky Alexander A.
Published: February 2019

Tomato, Lycopersicon esculentum Mill. `Asgrow 1035', was planted in Summer–Fall (Aug.–Dec.) 1998 in a land previously amended with compost in Fall 1997 and then cropped in sequence with three vegetables during the Fall–Winter–Spring 1997–1998. Soil was an Eau Gallie fine sand, and the production system was a full-bed polyethylene mulch with micro-(trickle) irrigation. Experimental design was a split-split plot replicated three times. Main plots were N and K fertilizer treatments for the Fall 1998 tomato crop: fertilized (FT 98) or nonfertilized (NF 98). Subplots were two N–P–K treatments for the Fall 1997 tomato crop: fertilized (FT 97) or nonfertilized (NF 97). Sub-subplots were four compost rates 0x, 1x, 2x, and 3x (where 1x = 10 t·ha–1 `Disneyworld' compost) that were applied for the Fall 1997 tomato crop. Fruit size and yields were best in the plots that received N and K in Fall 1998 (FT 98) and N–P–K in Fall 1997 (FT 97). Early yields (harvests 1 + 2) were highest with the 2x and seasonal total yields (six harvests) were highest with the 3x compost rate. Very high residual soil P and Fe concentrations were detected with increasing compost rates.
652 Beyond Subsistence: The Prospects and Problems of Horticultural Products in Agricultural Diversification of Developing Countries
Authors: Ahmed Raisuddin
Published: February 2019

Transformation of developing, subsistence economies into commercial and industrialized societies accompanies a declining share of agriculture in the gross domestic product (GDP). However, the shares of high-value products like horticultural, livestock and fish products increase with the decline of low-value products like cereals. This process of transformation is generally endogenous to various forces of supply and demand and, therefore, its pace can be influenced by policies. The forces in the demand side include income and income parameters of domestic consumers, and the ability to exploit foreign demand through exports of horticultural products. On the supply side, a large number of factors constrain the production of horticultural products. Agro-ecological constraints are country-specific. Technological backwardness, lack of quality control and standardization, weak marketing infrastructure including risk insurance, comparative advantages and institutional weakness in linking with world markets and exploiting economies of scale are some of the fundamental problems confronted by most developing countries. Export of horticultural products from developing countries is perhaps the most crucial factor that can impact the process of transformation mentioned above. Macro-economic policies that maintain a stable incentive structure for exports are important. But policies that respond to the constraints in the channel linking farmers in developing countries to supermarkets in the developed world are perhaps more important. Developing countries currently share only about 27% of world trade in horticultural products. More than 80% of this trade is, however, shared by only 31 developing countries. Barriers to entry into the developed market by new exporters of horticultural products are enormous. Whether the emerging forces of globalization under the auspices of WTO would make the entry problem more difficult or easier for vast majority of the developing countries is an open, but critical, question.
657 Genetic Determinants and Control of Fruit Softening
Authors: Bennett Alan B.
Published: February 2019

Fruit softening is integral to the ripening process. It is an important component of fruit quality, but also initiates deterioration and is a limiting determinant of shelf-life. Intensive research has attempted to elucidate the biochemical and genetic control of fruit softening with the goal of controlling this process as a means to enhance both fruit quality and shelf-life. Current models of fruit softening focus on cell wall disassembly as the major biochemical event regulating fruit softening. Examination of the sequence of cell wall disassembly in ripening Charentais melon fruit suggested that softening could be divided into two distinct phases. The early stage of fruit softening was associated with the regulated disassembly of xyloglucan polymers and the later softening that accompanies over-ripe deterioration was associated with pectin depolymerization. Characterization of cell wall changes in other fruit, including tomato, suggest that this may represent a general model of sequential cell wall disassembly in ripening fruit. Interestingly, the early events of xyloglucan disassembly were not associated with the activation or expression of xyloclucan hydrolases but were associated with the expression of a ripening-regulated expansin gene. Analysis of transgenic tomato fruit with suppressed expansin gene expression or with suppressed polygalacturonase gene expression supports a general model of sequential disassembly of xyloglucan and pectin that control the early and late phases of fruit softening, respectively.
659 Genetic Control of Fruit Quality and Prospects for Nutrient Modification
Authors: Giovannoni Jim
Published: February 2019

Recent advances in molecular genetics and genomics technologies have had a significant impact on tomato research over the last decade and are likely to have considerable influence on the nature and outcome of research activities related to tomato in the future. Specific applications of genomics technologies in our laboratory include positional cloning of genes associated with fruit ripening and quality (rin and nor), localization of ripening-related genes on the molecular-marker map to assist candidate gene discovery related to fruit ripening and quality, and characterization of mutants influencing fruit quality and nutritional value with the goal of identifying candidate genes for said mutants and alternative molecular tools for modification of fruit quality and nutrition. Isolation of the rin and nor genes has been verified via complementation of corresponding mutant tomato plants via insertion of the appropriate CaMV35s-driven wild-type sense cDNA. Both the rin and nor genes have sequence characteristics suggestive of transcription factors. Preliminary evidence suggests the role of similar genes in the ripening of additional climacteric and non-climacteric fruit species. Additional efforts in the laboratory include molecular analyses of light signal transduction as related to 1) regulation of carotenoid and flavonoid accumulation, and 2) potential manipulation of corresponding pathways for modification of fruit quality and nutrient value.
663 Biochemical and Molecular Determinants of Floral Senescence
Authors: Woodson William R.
Published: February 2019

The senescence of carnation (Dianthus caryophylus) flower petals is regulated by the phytohormone ethylene and is associated with the expression of a number of senescence-related genes. These genes encode enzymes in the ethylene biosynthetic pathway, including both ACC synthase and ACC oxidase. Members of these gene families are differentially regulated in floral organs, with specific members responsible for the increase in ethylene biosynthesis that leads to petal senescence. Pollination often serves as the external signal to initiate the senescence cascade. Following pollination, a rapid increase in ethylene production by the pistal occurs, which is subsequently followed by increased ethylene in the petal. This response is mediated by pollen–pistil interaction(s) that occurs only in compatible pollinations. Recent data indicate that the signal transduction cascade following this cell-cell communication involves protein phosphorylation, as pollination-induced ethylene is sensitive to protein kinase and phosphatase inhibitors. To date, our lab has cloned and characterized a number of senescence-related genes that are believed to play a role in the process of senescence. These include genes that encode enzymes involved in cell wall dissolution (b-galactosidase), protein degradation (cysteine proteinase) and detoxification of breakdown products (glutathione s-transferase). Many of these senescence-related genes are under the transcriptional regulation of ethylene, which has been characterized at the molecular level. A number of biotechnology approaches to controlling the senescence of flowers have been explored. These include the down-regulation of ethylene biosynthetic genes, the expression of a dominant-negative mutation of the ethylene receptor gene, and the expression of genes that lead to increased cytokinin levels in tissues. These will be discussed in relation to the potential for delaying senescence through genetic engineering.
667 Off-season Production of Horticultural Crops
Authors: Lin Hsin-Shan , Wang Chien Yi
Published: February 2019

Off-season production of several tropical and subtropical fruits has been successfully practiced commercially in Taiwan. By combining pruning, removal of leaves, and application of growth regulators, it is possible to have two to three crops of grapes per year. By grafting the chilled scions of temperate Asian pear onto the water shoots of low-chilling native pear varieties, it is possible to produce high-quality Asian pears (temperate-origin) in a subtropical environment. By using techniques such as root-pruning, flooding, and application of growth inhibitors, it is possible to induce flower bud formation and hasten the production of wax apples. The production periods of other fruit crops such as jujubes and sugar apples, can also be modified by pruning and other techniques.
671 Genetic Diversity in Actinidia and Conservation Strategy
Authors: Huang Hongwen
Published: February 2019

The genus Actinidia contains more than 66 species and 118 taxa. The best-known species is A. deliciosa C.F. Liang et A.R. Ferguson, the commercially developed kiwifruit. The natural range of Actinidia is remarkably wide, extending from the tropics (latitude 0°0′) to cold temperate regions (500°N). However, the original distribution of most taxa of Actinidia is centered around the mountains and hills of south-central and southeast China, with the QinLing mountain as its northern boundary and the HengDuan mountain as its western boundary. Sixty-two species, 114 taxa have been found in China. Genetic variation ranging from morphological traits to DNA is discussed in here. 1) Morphological variation (mainly horticulturally important traits): fruit size varies from 2 to 100 g, fruit skin color ranges from brown to green to white to purple, fruit surface from setose to villose, and flesh color from green to purple. 2) Nutritional value and flavor: vitamin C content varies from 10 mg/100 g to 1000 mg/100 g fresh fruit, soluble solids ranges from 2% to 22%, and flavor includes variation form bitter and astringent to desirable sour-sweet. 3) Gender variation includes six phenotype/genotypes of female, inconstant female, male, fruiting male, neuter and hermaphrodite. 4) Ploidy variation is consist of 2x, 4x, 6x, 8x in both intra- and inter-taxa variation. 5) Isozyme genetic variation: high polymorphisms were detected in commercial cultivated species and 28 wild species. 6) Genetic diversity was evaluated by RAPD, SSR, PCR-RFLP of mtDNA and cpDNA, a high level of genetic diversity was found in both inter-taxa and intra-taxa. Conservation strategy for diverse genetic resources of Actinidia in China is also discussed.
692 Plant Embryo Culture Techniques and Applications
Authors: Bridgen Mark P.
Published: February 2019

Traditional and biotechnological breeding techniques are being united to develop exciting new plants and to improve existing cultivated plants by introducing natural variability from germplasm resources. Intervarietal, interspecific and intergeneric crosses can be accomplished by using plant embryo culture techniques, sometimes also referred to as embryo rescue. Embryo culture involves the isolation and growth of immature or mature zygotic embryos under sterile conditions on an aseptic nutrient medium with the goal of obtaining a viable plant. The technique depends on isolating the embryo without injury, formulating a suitable nutrient medium, and inducing continued embryogenic growth and seedling formation. The culture of immature embryos is used to rescue embryos from hybrid crosses that were once thought to be incompatible because they would normally abort or not undergo the progressive sequence of ontogeny. The culture of mature embryos from ripened seeds is used to eliminate seed germination inhibitors, to overcome dormancy restrictions, or to shorten the breeding cycle. New and exciting cultivars of Alstroemeria, also known as Lily-of-the-Incas, Inca Lily, or Peruvian Lily, have been bred by using zygotic embryo culture; these techniques and applications will be discussed.
Interactions Among Rooting Substrate, Phenological Stage of Cuttings, and Auxin Concentration Impact in In Vivo Rooting of Cotinus obovatus
Authors: Denny Geoffrey C. , Arnold Michael A.
Published: February 2019

A study was conducted to determine the effects of substrate, phenological stage of cuttings, and auxin concentrations on the rooting of Texas smoke tree (Cotinus obovatus Raf.). Softwood, semi-hardwood, and hardwood cuttings were treated with either a 0, 5,000, 10,000, or 15,000 mg·L-1 (ppm) potassium salts of indolebutyric acid (K-IBA) and placed in either 50% peat: 50% perlite or 100% perlite rooting substrates. Cuttings were places under an intermittent mist system in a greenhouse for 8 weeks. Softwood cuttings rooted in both substrates, but the 50% peat: 50% perlite substrate produced better-quality rooted only in the 100% perlite substrate. In 100% perlite substrate, the optimal concentration for semi-hardwood cuttings was ≈12000 mg·L-1 (ppm) K-IBA, while hardwood rooting was maximized at 15000 mg·L-1 (ppm) K-IBA or more.
Fertilizer, Flower Bud Removal and Vegetative Pruning of Echinacea species (Purple Coneflower) Influence Biomass and Phenolic Content
Authors: Vires Jenny Heringer , Anderson Robert , Geneve Robert
Published: February 2019

Purple Coneflower [Echinacea sp. (Asteracea)] is of great value to the horticultural, pharmaceutical, and herbal industry. More research is needed to determine cultural practices that will produce a plant high in biomass and phenolic content, the chemical used for testing the quality of the harvested plant on a percent basis of roots, flowers and vegetative parts. The objective of this experiment is to determine if biomass and phenolic content of Echinacea purpurea and E. purpurea `Magnus' is influenced by fertilization after flower bud removal and vegetative pruning. The second objective of this study is to form an evaluation of the differences in biomass and phenolic content of five cultivars of E. purpurea and five species of Echinacea. Biomass and phenolic content will be evaluated to determine if exposing these plants to various treatments increases the quality of the plant over 1 and 2 years of growth. Differences in dry weights of Echinacea species and cultivars harvested after the first year of growth was determined. There was a significant difference in total dry weight between E. purpurea cultivars. Echinacea purpurea `Bright Star' and `Clio' significantly produced the most total dry weight compared to all other cultivars. There was no significant difference in root or flower biomass between cultivars. Biomass of Echinacea species was significantly different in root, vegetaive and flower parts. The total biomass of E. purpurea and E. tennesseensis was significantly higher compared to other species. Echinacea pallida and E. paradoxa were not significantly different from E. purpurea in root biomass, even though both species were small in above ground growth. Echinacea tennesseensis significantly produced 45% to 105% more flowers compared to other species. Differences in phenolic content between species and cultivars will also be presented.
The Need for a Regional Small Fruit Center
Authors: Poling E.B.
Published: February 2019

Working on the basic idea that the small fruit industries in Virginia, South Carolina, Georgia, Arkansas, and other states in the south have a great deal of growth potential, especially in strawberries, the Southern Region Small Fruit Center is now becoming a very focused collaboration between several land-grant institutions to develop a virtual small fruit center web site that will serve to keep specialists, agents, growers, and students well informed on the latest small fruit research and technical findings. It would also give instant access to a variety of small fruit extension publications, budgets, and crop advisories. The site, www.smallfruits.org, opened on 17 Sept. 1999, and was immediately utilized after Hurricane Floyd “hit” to post a series of berry info advisories on specific postplant management strategies to minimize further yield losses due to the extra week of delayed planting caused by Floyd's flooding. The main benefit of regional or multistate institutional approach is that it gives us the “extra horsepower” for tackling some fairly ambitious projects, like the creation of a virtual small fruit center. Recently, the center has begun to offer more in-depth regional training courses for agents and growers, such as the “Extension Strawberry Plasticulture” short course that was conducted on North Carolina State Centennial Campus, 1-5 Nov. 1999. We currently have a “critical mass” of some of the best small fruit research and extension workers you will find anywhere across the whole southern region, and by working together we can develop stronger, more economically viable small fruit industries.
The Agricultural Research, Extension, and Education Reform Act of 1998: Examining Its Key Provisions
Authors: Beaulieu Lionel J. (Bo)
Published: February 2019

The Agricultural Research, Extension, and Education Reform Act of 1998 (AREERA) represents a concerted effort on the part of federal legislative leaders to rethink the manner in which agricultural research and extension programming are undertaken within the land-grant university system of our nation. For the first time ever, land-grant schools are being mandated to increase their energies in support of “multi” activities; namely, multiinstitutional, multidisciplinary, multifunctional, and multistate activities. The intent is to bring about greater efficiencies in carrying out the research and extension missions of our land-grant entities.

In this presentation, the key provisions of AREERA are outlined. These elements include: 1) the commitment of 25% of Hatch formula funds in support of multidisciplinary research involving another agricultural experiment station, Agricultural Research Service, or college/university that collectively are seeking to solve problems that concern more than one state; 2) the expenditure of Smith-Lever formula funds for support of multistate extension activities equivalent to 25% of these formula funds, or twice the level of resources devoted to such activities using FY97 funds; and 3) a directing of 25% of Smith-Lever and Hatch funds received by an institution in FY2000 for integrated research and extension activities (or twice the level of effort committed to such efforts in FY97). It is further noted that while 1890 and 1994 institutions are required to engage in multidisciplinary, multistate, and integrated research and extension activities, they are not compelled to meet the 25% goal outlined in the AREERA legislation.

Aside from the resources that must be devoted to certain activities within the Agricultural Experiment Station and the Extension Service, AREERA makes quite clear the need to actively engage stakeholders in giving shape to the priority activities of these land-grant entities. Moreover, it notes the importance of documenting the impact of the institution's research and extension investments on the priority concerns of its stakeholders. Among the key questions that will be employed to evaluate the quality of an institution's efforts are the following: Did the program address a critical issue? Did it address the needs of underserved and underrepresented populations in the state(s)? Did the investments result in improved program effectiveness and/or efficiency? Indeed, AREERA changes the landscape for many of the South's land-grant institutions. However, if efforts undertaken to date are any indication, the leadership and faculty of the region's land-grant system will successfully respond to the challenges that AREERA poses for them.
Can Multi-state Extension Programming Succeed?
Authors: Parker Michael L. , Unrath C. Richard , Lockwood David
Published: February 2019

With the current situation facing land grant universities of declining resources and a portion of federal funding being dependent upon multistate activities, the search for means to successfully address clientele needs may be handled through multistate activity. In the Southeast, the tree fruit programs, both research and extension, have been evaluating areas that could be addressed with multistate programming. To date, most of the tree fruit multistate activities have been informal in nature. The apple program was the first to look at multistate activity because of the heavy concentration of the industry in the mountains of NC, SC, GA, and TN. The formation of the Southeastern Apple Growers Meeting, which combined the annual educational meeting for apple growers in NC, GA, SC, and TN, was the first initiative. It proved to be very successful with the completion of the eighth joint meeting. In addition, the pest management guides for both apple and peach have been combined for many of the southeastern (five states) and southern states (11 states), respectively. Numerous working groups, workshops, tours, and field days are held on a regional scale as well. However, in order for multistate programming to succeed, our experience suggest the need for several key components. The technical competence in the program to be addressed, a supportive university administration, backing of the industry groups, and personnel that are neither territorial nor resistant to change must be present. From our experience multistate programming can be very successful!
Genetic Diversity Evaluations of Threatened Ozark and Allegheny Chinkapin Populations
Authors: Dane Fenny , Fu Yuqing
Published: February 2019

Chestnut blight, caused by the Asian fungus Cryphonectria parasitica, has severely affected chinkapin populations (Castanea pumila), especially those limited to the Ozark mountains (var. ozarkensis). Genetic diversity within and between geographic populations of the Allegheny (var. pumila) and Ozark chinkapin populations was evaluated for development of appropriate conservation strategies. Nuts or dormant buds collected from populations along the range of the species were analyzed using allozymes. A unique allele was detected in populations along the gulf of Mexico. Significant differences in genetic diversity were observed among Allegheny populations, but not among Ozark populations. High levels of genetic identity were detected among widely distributed populations from Florida to Virginia (Allegheny chinkapin populations) and Arkansas (Ozark chinkapin populations).
A Comparison of Overhead Irrigation Scheduling and Switch Tensiometers
Authors: Bush Edward , Gray Ann , Thaxton Virginia , Wilson Paul
Published: February 2019

Proper irrigation management is essential for producing quality container-grown woody ornamentals and reducing off-site runoff. Research has shown that tensiometers can be used as an effective tool to schedule irrigation for woody ornamentals. The objective of this experiment was to compare the effect of cyclic and tensiometric irrigation methods on growth of lantana. Lantana camara `New Gold' liners were established in a 3 pine bark: 1 peat:1 mason sand (by volume) medium. Low-tension switch tensiometers were compared to scheduled overhead [one time a day (1×) at 0600 and cyclic irrigation three times a day (3×) at 0600, 1200, and 1800] for the production of 1-gallon lantana plants. Three low-tension tensiometers (1/block) were set at 7 cb and allowed to irrigate over a 12-hour period. Three separate planting dates occurred and then terminated after ≈7 weeks. Tensiometric irrigation increased root and shoot growth compared to scheduled irrigation for the 24 May 1999 harvest date. Cyclic irrigation produced plants with shoot and total root weights >1× and tensiometer treatments for the September harvest date. Tensiometers sharply reduced irrigation requirements compared to scheduled irrigation volume by at least 50% of the 1× and 3× treatments weekly. Analysis of nutrients in leachate for June indicated increased B and Fe concentrations in the 3× irrigation treatment. Lower concentrations of Ca, Mg, and Na were measured in August. Lantana growth was acceptable for all irrigation treatments and harvest dates.
Optimal Harvest Time and Effect of Storage Time on Quality of Apples Grown in Mississippi
Authors: Sindoni Maria J. , Matta Frank B.
Published: February 2019

Maturity indices such as fruit size, firmness, fresh fruit weight, soluble solids content, titratable acidity, and juice pH of `Earligold'/EMLA 7, `Jonagold'/EMLA 111, `Improved Golden'/EMLA 7, `Improved Golden'/EMLA 111, `Scarlet Gala'/EMLA 7, `Jonafree'/Mark, `Macspur'/M 7A, `Royal Gala'/MM 111, and `Williams Pride'/M 7A were monitored. Based on maturity indices analysis, the optimal harvest time for each scion rootstock combination was determined. `Scarlet Gala'/EMLA 7, `Williams Pride'/M 7A, and `Earligold'/EMLA 7 were early cultivars, while `Jonagold'/ /EMLA 111, `Improved Golden'/EMLA 7, `Improved Golden'/EMLA 111, and `Macspur'/M 7A were late cultivars. After harvest, all cultivars were stored for 3 months under controlled conditions. Changes in fruit appearance, flavor, sweetness, tartness, and firmness were recorded. Fruit size, firmness, fresh fruit weight, soluble solids content, and juice pH were influenced by the cultivar/rootstock combination. Results of the sensory evaluation indicated that medium and late cultivars were preferred by panelists compared to the early harvested cultivars. `Improved Golden'/EMLA 7, `Royal Gala'/MM 111, and `Jonagold'/EMLA 111 combinations maintained quality during storage, compared with the remaining cultivars/rootstock combinations, and had a longer storage life.
Municipal Yard Waste as a Nutrient Source for Apple Trees
Authors: Ebel Bob , Himelrick David G. , Caylor Arnold , Wilkins Bryan
Published: February 2019

The Environmental Protection Agency has developed regulations requiring municipalities to reduce the amount of solid wastes going into landfills. One potential outlet for yard waste is agriculture. This study was conducted during the first 6 years of orchard establishment to compare tree and fruit response of `Fuji', `Golden Delicious' and `Red Delicious' apple trees to composted yard waste and other conventional fertilizers. Calcium nitrate and urea were applied at 16.8, 33.6, and 67.3 kg·ha–1 N per year. Composted municipal yard waste was applied at 1.3-, 2.5-, and 5.0-cm depths, within the sod-free strip of the tree row. Yard waste promoted growth compared to calcium nitrate and urea allowing the trees to fill their allotted space earlier. Yield and yield efficiency were generally similar across all forms of fertilizers. Foliar N was not affected by the form of nitrogen used, did not vary across the different rates of calcium nitrate and urea, and was well within the range considered sufficient (1.8% to 2.5%) for all treatments. It is concluded that the accelerated growth by yard waste was not due to N nutrition. Other foliar element levels were not consistently affected by fertilizer form or rates for the three cultivars. Fruit weight, length/diameter ratio, firmness, and soluble solids were generally not negatively affected by the yard waste, although some fruit were slightly softer and soluble solids slightly lower than fruit from trees treated with calcium nitrate and urea. This study demonstrates that municipal yard waste may provide benefits to a fertilization management system for apple orchards by promoting early growth.
Using Geospatial Techniques and GIS to Develop Maps of Freeze Probabilities and Growing Degrees
Authors: Logan J. , Mueller M.A.
Published: February 2019

Tennessee is located in an area of diverse topography, ranging in elevation from <100 m to ≈2000 m, with numerous hills and valleys. The physiography makes it very difficult to spatially interpolate weather data related to vegetable production, such as spring and fall freeze dates and growing degree days (GDD). In addition, there is a poor distribution of cooperative weather stations, especially those with 30 years or more of data. There are climate maps available for Tennessee, but they are of such a general format as to be useless for operational applications. This project is designed to use a geographic information system (GIS) and geospatial techniques to spatially interpolate freeze (0 °C) dates and GDD for different base temperatures and make the data available as Internet-based maps. The goal is to develop reasonable climate values for vegetable growing areas <1000 m in elevation at a 100 square km resolution. The geostatistics that we are evaluating include Thiessen polygons, triangulated irregular network (TIN), inverse distance weighting (IDW), spline, kriging, and cokriging. Data from 140 locations in and around Tennessee are used in the analysis. Incomplete data from 100 other locations are used to validate the models. GDD, which have much less year-to-year variability than freeze dates, can be successfully interpolated using inverse distance weighting (IDW) or spline techniques. Even a simple method like Thiessen produces fairly accurate maps. Freeze dates, however, are better off analyzed on an annual basis because the patterns can vary significantly from year to year. The annual maps can then be superimposed to give a better estimate of average spring and fall freeze dates.
Evaluation of Plant-bed Fertility in Vidalia Onions
Authors: Boyhan George , Torrance Reid , Curry David , Lewis Pam , Linton Mindy
Published: February 2019

In 1998–99, experiments were conducted to evaluate current fertility practices with plant-bed onions. In experiments in 1998 and 1999, a factorial experiment of preplant 5–10–15 and CaNO3 sidedressing indicated that CaNO3 had a significant effect on foliar nitrogen levels. CaNO3 also had an effect on stand count in 1998, but not in 1999. CaNO3 and 5–10–15 had an effect on plant height in both 1998 and 1999, with an interaction between 5–10–15 and CaNO3 in 1999. In 1999, transplants were also evaluated on an acceptability scale with 5–10–15 and CaNO3 rates resulting in significant differences in transplant acceptability. Postseedling applications of high phosphorus fertilizer were also evaluated. There were no consistent improvements in transplant growth with applications of high phosphorus fertilizers, such as 18–46–0 or 10–34–0, either on soils with very high residual phosphorus (242 lb/acre) or medium residual phosphorus (50 lb/acre). In addition, variety was not a factor in these responses.
Oxygen Radical Absorbance Capacity (ORAC), Phenolic, and Anthocyanin Concentrations in Fruit and Leaf Tissue of Highbush Blueberry
Authors: Ehlenfeldt Mark K. , Prior Ronald L.
Published: February 2019

Antioxidant capacity as measured by ORAC, total phenolic, and total anthocyanin concentrations were evaluated in fruit tissue of 86 highbush blueberry cultivars, and ORAC and phenolic levels evaluated in leaf tissue of the same materials. Average values for ORAC, phenolics, and anthocyanins in fruit were 15.9 ORAC units (1 unit = 1 micromole Trolox Equivalent), 1.79 mg·g–1 (gallic acid equivalents), and 0.95 mg·g–1 (cyanidin-3-glucoside equivalents), respectively. ëRubel' had the highest ORAC values, at 31.1 units. Values for ORAC and phenolics in leaf tissue were significantly higher than fruit tissue, with mean values of 490.4 ORAC units and 44.8 mg·g–1 in leaf tissue, respectively. No significant correlations were found between fruit ORAC and leaf ORAC, or between fruit ORAC and leaf phenolics. Investigation of ORAC values in a family of 44 `Rubel' × `Duke' seedlings showed negative epistasis for ORAC values. However, an analysis of ORAC values vs. pedigree in plants from the 86 cultivar groups suggested that across cultivars, ORAC inheritance is generally additive.
Comparison of Chilling Requirement in `Ta Tao' Budded Peach Trees by Shoot Forcing
Authors: Gibson P.G. , Reighard G.L.
Published: February 2019

Peach trees exposed to `Ta Tao' vegetative chip bud grafts have been shown to have physiological changes that include bloom delay, delayed maturity, reduced shoot vigor, and early autumn defoliation. `Ta Tao' is known to be infected with the graft transmissible agent Peach Latent Mosaic Viroid (PLMVd). PLMVd has been associated with bloom delay and reduced shoot vigor. `Coronet' peach trees planted in a high-density, Y-trained orchard system were treated with vegetative chip buds from `Ta Tao'. Transmission of PLMVd was confirmed in the treated trees by cRNA probe hybridization. A shoot forcing study was set up to determine if exposure to `Ta Tao' would alter the chilling requirement of `Coronet' peach. Terminal fruiting shoots were collected periodically during the dormant season from 8 Jan. 1999 to 19 Feb. 1999, which represented a range of chill hour accumulation from 574 to 927, respectively. Shoots were forced in a greenhouse, and chilling requirement was considered complete when 50% of the flowers opened. Chilling requirement was not changed by exposure to `Ta Tao' chip buds. The number of days required for shoots to bloom was significantly and consistently longer for the `Ta Tao' treated trees. The number of shoots responding to forcing conditions was significantly less in the treated trees. The data suggest that the graft transmissible effects from `Ta Tao' buds increased the growing degree hours required for `Coronet' leaf and flower bud emergence after rest completion under greenhouse forcing conditions.
Importance of Organophosphate (OP) Insecticides in an IPM-based Peach Orchard Management System
Authors: Jervis B.D. , McCraw B.D. , Mulder P.G.
Published: February 2019

The Food Quality Protection Act provides for review of pesticide use on food products providing potentially significant challenges to orchardists. IPM should reduce pesticide use but not fruit quality. This project compares effectiveness of OP and non-OP insecticides used in an IPM peach management program and compares spray program efficiency in commercial peach orchards. OP vs. non-OP insecticide treatments (Guthion and Lorsban vs. Thiodan and Asana) targeting plum curculio (PC) and plant bugs (PB) were applied to 7-year-old `Cresthaven' and `Jayhaven' trees in a split-plot design. Insect damage to fruit samples from commercial orchards was compared to the IPM demonstration orchard. PC insecticide application was based on a threshold of 0.1 PC per trap per day from screen traps. `Jayhaven' and `Cresthaven' trees in the IPM demonstration orchard received three and four insecticide applications, respectively. Total fruit yield was not significantly different between OP and non-OP plots. Total PC damage from `Jayhaven' trees in OP plots was 4.8% compared to 8.2% from non-OP plots. Less than 2% of fruit from `Jayhaven' and `Cresthaven' trees in OP plots contained PC larva compared to >6% from non-OP plots. PB damage to fruit was slightly higher in OP vs. non-OP plots. Insecticide applications in commercial orchards ranged from six to 12, resulting in PC damage ranging from 0% to 8.2%.
Pine Pole and Post Peelings Have Potential as Blueberry Growing Media and Soil Amendment
Authors: Krewer Gerard , Ruter John , NeSmith D. Scott , Clark James , Otts Tony , Mullinix Ben
Published: February 2019

Growing southern highbush blueberries in milled pine bark beds ≈15 cm deep has become a popular fruit production system in Georgia and Florida. One of the primary limiting economic factors in this system is the cost of the growing media, which can exceed $10,000 U.S. per ha. In an effort to discover low-cost substitutes for milled pine bark, available waste or low-cost organic materials were screened for there suitability as growing media for southern highbush blueberries. Cotton gin waste, pecan shells, hardwood “flume” dirt, milled composted urban yard waste, composted urban tree trimmings, pine telephone pole peelings, and pine fence post peelings were evaluated. Only pine derived materials had a suitable pH (<5.3). Fresh pine telephone pole peelings (≈25% bark to 75% elongated fibers of cambial wood) and pine fence post peelings (≈75% bark to 25% elongated fibers of cambial wood) were evaluated for several seasons in containers and field trials. The growth index of blueberries in these materials was slightly less or equal to milled pine bark. Surprisingly, nitrogen deficiency was slight or not a problem. The results indicate that pine pole and post peelings may offer an excellent, low-cost substitute for milled pine bark for blueberry production.
Occurrence of Preharvest Peel Streaking Is Associated with Gummosis and Pesticide Usage in Peach
Authors: Taylor K.C.
Published: February 2019

The absence of red color in a streaked “Bleaching” pattern is periodically noted on late-season peaches in middle Georgia. The streaked pattern led to a hypothesis that accumulation of pesticides in the stem end of the fruit prevented anthocyanin formation. However, analysis of pesticide residues on affected and unaffected peel suggested this was unlikely. We observed that trees affected by fungal gummosis (caused by Botrysphearia dithodia) were most often affected by the “bleaching” phenomenon and that `Summer Gold', the most fungal gummosis–susceptible variety, had the greatest incidence of the disorder. In a preliminary trial, we tested the hypothesis that fungal gummosis mediates “bleaching” by interfering with anthocyanin color formation in the peel of developing fruit. Tree gum/resin and pesticides were tested for their effect on peel color development. The gum/chemical preparations were dripped onto fruit prior to anthocyanin or red pigment formation in peach peel. After the anthocyanescent period, fruit were observed for bleaching. The gum mediated a negative effect by sulfur, captan, and carbaryl in peel color formation in peach. Fenbuconizole and phosmet had a less negative effect on color formation, although the effect was noticeable. The gum alone, propiconizole, and chlorothalonil did little to effect on peel color formation.
The Evolution of Plant Evaluation and Introduction Programs at the JC Raulston Arboretum
Authors: Lyons Robert E.
Published: February 2019

An historic feature of the JC Raulston Arboretum (JCRA) is to identify new and unusual ornamental plant materials for landscape use through an active program of observing landscape performance at the JCRA in Raleigh. Introduction of plant materials into commerce occurs primarily through programs conducted in concert with the North Carolina Association of Nurserymen and through a unique policy of “open access” for nurserymen. One program, The JC Raulston Selections Program, returns revenues to the general operations and maintenance functions of the JCRA; others are not revenue generating, and are provided as a service to the industry. To a lesser extent, the general public may participate in receiving new plants via a special program offered through JCRA membership. The JCRA is also an official trial garden site for the All America Selections program and seed companies. Elements of these introduction and evaluation programs will be discussed within the context of the past, present, and plans for the future for program maintenance and possible changes.
Integrating Plant Trials into Teaching and Graduate Research Programs
Authors: Arnold Michael A.
Published: February 2019

Plant trialing and promotion programs have become popular in recent years with many state and some regional programs emerging. Successful implementation requires considerable labor, facilities, and monetary resources for evaluation of large numbers of taxa over several years to ensure that plants are well adapted to the region of interest. Research and development funds and cooperator commitment to trialing programs can be limiting during the early years of these programs prior to production of tangible benefits. Dedicated facilities for program activities are usually not available. Mechanisms for development of facilities and procurement of labor to augment trialing program resources, while enriching undergraduate and graduate teaching and research programs, will be presented.
The University of Arkansas Plant Evaluation Program
Authors: Lindstrom Jon T. , Robbins James , Klingaman Gerald , Starr Scott , Carlson Janet
Published: February 2019

The Univ. of Arkansas initiated a statewide plant evaluation program in 1999. This trial will enable us to evaluate plants on a statewide basis, improve statewide marketing programs, and serve as a propagation source for nonpatented or non-trademarked material. Trees and shrubs will be evaluated for 5 years and herbaceous material for 3 years. Three test sites were established across the state, one in Fayetteville, Little Rock, and Hope, Ark. These sites correspond to the three USDA plant hardiness zones found in Arkansas (Zones 6, 7, and 8). A consistent planting protocol (e.g., distance between plants, irrigation system, bed width) is used at all three locations. Data collection consists of annual growth measurements and qualitative evaluations for factors such as time of flowering, length of flowering, and disease or insect problems. A standard protocol has been established for identifying future plants to be evaluated in the program. In the first year, 17 accessions were planted at each of the three different locations. Best plant growth on 15 of the 17 accessions occurred at the Little Rock site. This may be a reflection of the environment present at the sites in Hope and Fayetteville. Both of these sites are exposed, full-sun situations, whereas the Little Rock site receives some afternoon shade. Reception to this trial program has been favorable, with the Little Rock site gaining much attention from the Arkansas nursery industry.
Horticultural Trials: Balancing Academic Goals with Industry Support
Authors: Armitage Allan M. , Green Meg
Published: February 2019

The horticulture research gardens at the Univ. of Georgia were initiated in 1983, and have significantly evolved in visibility and functionality. The gardens were designed to act as a research evaluation site for the industry, but also to be used as a teaching tool for classroom, and to encourage student experience in landscape plant maintenance. Performance evaluation is accomplished by gathering data every 2 weeks, and performance plots are drawn for each taxon at the end of the season. Data on performance of perennial plants are also recorded, and each taxa is summarized after its flowering period. All data is compiled, simplified, and disseminated by booklet, trade magazine papers, and the Internet. In the last 7 years, a major cornerstone of the garden has become the evaluation and introduction of new crops for the ornamental plant industry. At least a dozen new taxa have been introduced. New crop introduction programs will be discussed as a potential means of funding. The ability to initially raise funds for horticultural trials the maintenance of funding over the years will also be discussed.
The University of Tennessee Gardens and Herbaceous Plant Evaluation Program
Authors: Hamilton Susan L.
Published: February 2019

Many new plants and varieties are introduced into the market every year. Little information is generally available about the landscape performance of these plants. To take the guesswork out of their landscape performance in the Tennessee region, the Univ. of Tennessee Institute of Agriculture (UTIA) Gardens were established. Started in 1983 as an All-America Selections (AAS) Test Garden, on less than a quarter of an acre, the UTIA Gardens have grown to 5 acres and now include plant introductions from 25 commercial seed and plant companies. An average of 550 summer and winter annuals are evaluated annually in addition to an assortment of bulbs, perennials, herbs, groundcovers, ornamental grasses, aquatics, trees, and shrubs. Because of the volume of plants, evaluation criteria are in conjunction with industry requests and are not always replicated. In addition to university support, the gardens receive revenues from the sponsoring commercial seed and plant companies, the Tennessee green industry trade associations, a “Friends of the Gardens” support group, and gifts. As a result of the herbaceous plant evaluation program, the UTIA Gardens have grown to be a significant resource for the university, community, and green industry. A variety of university departments use the gardens in their teaching; community groups, including schools, tour and use the gardens; and open houses and field days assist commercial growers and landscapers in remaining current on new plant introductions and their performance.
Texas SuperStars: The Coordinated Educational Marketing Assistance Program in Texas
Authors: Mackay Wayne A. , George Steve , Davis Tim , Arnold Mike , Lineberger Dan , Parsons Jerry , Stein Larry
Published: February 2019

The Coordinated Educational Marketing Assistance Program (CEMAP) is one of the oldest marketing assistance programs for ornamentals in the United States. The goal of this program is to identify outstanding plants for Texas and to provide support for the nursery industry, thereby making plants with superior performance available to the people of Texas. The CEMAP program is a cooperative effort between the Texas nursery industry and Texas A&M Univ. The CEMAP Executive Board has eight individuals representing extension, research, and teaching plus two administrative liasions and the Industry Advisory Board has ≈50 members from all segments of the ornamentals industry in Texas. Funding for the CEMAP program comes from direct industry support and from the public through the sale of plant tags or other promotional materials which bear the Texas Superstars logo. The logo is trademarked and licensed to printing companies who handle the administration of royalties to the program. The Executive Board makes the final decision about which plants are designated Texas Superstars. Promotional support for the plants is provided by CEMAP through point of purchase materials and publicity through print, radio, and television. In addition, the Texas Nursery and Landscape Association in cooperation with the Texas Department of Agriculture are conducting a publicity campaign to inform the public about Texas Superstars.
Controlled Water Table Irrigation System Effect on Growing Medium Water Potential
Authors: Mach C.A. , Buxton J.W. , Gates R.S.
Published: February 2019

The CWT irrigation system consists of a capillary mat placed on a level bench so one side extends over the edge of the bench into a trough containing a nutrient solution maintained at a controlled distance below the bench. The nutrient solution is drawn by capillarity up to and over the bench surface. As plants use the nutrient solution or as water evaporates from the media, it is replaced from the trough. The automatic system maintains a constant air/water ratio in the growing media. Geraniums were grown in a peat based media in 15-cm pots at 0, 2, and 4 cm CWT. In a separate study, the water potential was determined in two media. Water potential was determined at the bottom, middle, and top of the container at 0, 2 and 4 cm CWT every 2.5 hrs during the light period. Geraniums at 0 and 2 cm had the greatest leaf area and dry weight. The 0- and 2-cm treatments were >25% greater than plants at 4 cm CWT. The roots of plants at 0 cm CWT were concentrated at 2–4 cm above the bottom of the container, whereas roots at 2 cm CWT uniformily extended from the center to the bottom. Water potential was about the same in each media within each CWT treatment. The water potential from top to bottom decreased slightly about midafternoon on a sunny day when water demand was the greatest. Media at 0 CWT at the container bottom had 0 water potential; whereas the water potential at 2 and 4 CWT had a lower water potential.