bluuebunny/crossref_metadata_2025 huggingface dataset:
National Electronic Information Systems–Agricultural Databases for Decision Support
Authors: Eastwood B.R.
Published: February 2019

A number of factors have emerged in recent years, grown in importance, and are now converging rapidly to create a window of opportunity for all of us. These factors constitute six separate, but related and important, categories: 1) Decreasing staff in the nation's Cooperative Extension System; 2) increasing complexity of agricultural production technologies; 3) increasing concerns of society; 4) opening of markets globally; 5) increased need for accountability; and 6) rapid progress in computerized information and communication technologies. These factors concurrently are causing greater sharing of expertise and resources across states, institutions, and departments; more cooperation with the private sector; improved openness and communication on issues of interest to the community; greater awareness of our role in the world; and a willingness to consider new approaches. One of these approaches involves the development of comprehensive national decision support resources for producers and those who work with producers in an educational, advisory or service role. This program, which has evolved over the past 10 years, is Agricultural Databases for Decision Support (ADDS). ADDS projects may be developed for any commodity, clientele, or major issue area. Products already available include the National Dairy Database and the National Pig Information Database. Several additional projects are underway and more will be added as interest warrants. The ADDS hallmark applies to those projects that follow the philosophy and meet the criteria agreed to by the greater community of developers and users. ADDS uses the sophisticated search and retrieval mechanism and multimedia capabilities of commercially available software. This software is applied to a cooperatively developed national resource of peer-reviewed materials that are selected by experts for their usefulness.
Effects of Fertigation and Ground Application on Nutrient Movement and Tree Response in Eastern Soils
Authors: Stiles Warren C.
Published: February 2019

Distribution of nutrients was evaluated in samples collected at various depths and distances from drip emitters after 8 years of application. Nutrients applied to soil surface influenced levels mainly in top 40 cm of the soil profile, while fertigation resulted in movement to depth of 80 cm within the wetted zone. NO3-N was increased in 0- to 40-cm depths by soil surface application, but below 40 cm by fertigation. Fertigation increased P in wetted zone to a 40-cm depth. Surface-applied K increased levels in the 0- to 20-cm zone, while fertigation increased K to the 80-cm depth. Zn and Cu were increased to 80 cm by fertigation. Growth and yield indicate soil surface application of fertilizers plus drip irrigation to be comparable to fertigation in most experiments. Fertigation of mature trees on M.7 with K + B for 3 years did not show consistent positive effects on fruit size or color. Responses associated with fertigation appear to be largely attributable to irrigation unless soil nutrient supplies are inadequate.
Funding Opportunities for Children's Gardening Research
Authors: Bradley Jennifer Campbell
Published: February 2019

The benefits of horticulture to our society have long been known. Just recently, we are beginning to see the valuable role that horticulture can have on impacting youth. However, research into this area has been limited. As this avenue of horticulture is growing, so is the need to continue and establish substantial research into this area. One important obstacle to overcome is funding. While a desire to pursue the effects of horticulture on youth exists, too often a lack of financial support has limited the depth and scope of research. Finding and establishing funding allows the researcher to explore and allocate the resources necessary to continue reputable research. This workshop will explore various funding opportunities for research in the area of children and gardening. Areas of discussion will include sources for funding as well as generating a proposed idea, refining your idea, documenting the need, and establishing uniqueness of your study. This talk will focus on finding and establishing funding for children's gardening research—a much needed necessity to help document and establish the benefits and importance of youth gardening programs.
Oak Savannah Restoration—The First Year After a Control Burn
Authors: Irish Brian , Wheeler Laurin
Published: February 2019

A control burn was conducted in a mixed black oak—white oak—post oak stand to determine the effectiveness of fire at removing midstory and understory trees. The midstory and understory was predominately invading species of red maple, dogwood, black cherry, black gum, and mockernut hickory with lesser amounts of canopy species—black oak, white oak, post oak, and blackjack oak. A total of 17,000 stems/ha were top killed. All stems below 10 cm (15,600 stems/ha) were killed and all of the invading species were all top killed. Large black oak (greater than 20 cm) were killed by hypoxylon which may or may not have been related to fire. Soil pH increased from 4.6 (before) to 5.7 after the burn. The litter layer was almost completely removed. The biomass of the litter layer the year after the burn was 23% of the biomass before burning. Herbaceous plants began to invade the site in the first summer.
Disease Incidence on Old Garden Roses in the South
Authors: Clendenen Beth , Behe B.K. , Bowen K.L.
Published: February 2019

Eleven rose cultivars were field planted and evaluated weekly for disease, defoliation, and overall vigor in order to compare natural resistance to blackspot (Diplocarpon rosae). Alternative treatments were also compared for efficacy in low-maintenance disease control. Treatments included a bimonthly application of chlorothalonil, a bimonthly application of a horticultural oil, an application of chlorothalonil based on rain events, and a no-treatment control. Cultivars showed significant differences in disease severity, defoliation, and overall performance, with old garden rose varieties showing more natural disease resistance than modern susceptible varieties included in the study. Chlorothalonil applied on a 14-day spray schedule did provide a significant decrease in blackspot disease severity when compared to other treatments. A significant incidence of secondary disease including Cercospora rosicola and Botrytis cinerea occurred on old garden rose varieties. No treatment differences were found for these diseases. `Belinda's Dream', `The Fairy', and `Red Mediland' ranked highest in overall performance throughout the season.
Responses of Nine Containerized Perennials to Sumagic
Authors: Latimer Joyce G. , Thomas Paul A.
Published: February 2019

Nine perennial bedding plants were screened for responsiveness to the plant growth retardant, Sumagic (uniconazole-P). Two weeks after planting, plugs were treated with one foliar spray of Sumagic at 0, 40, 80, 120, or 160 ppm at the label-recommended volume. Plant growth of Gaillardia grandiflora `Goblin' was not reduced by Sumagic. Height of Achillea × `Moonshine' was reduced 8% to 12% at 4 weeks after treatment (WAT), and the reduction persisted through 8 weeks after planting (WAP) to the landscape. Phlox paniculata `Joliet' responded linearly to increasing Sumagic rate with a maximum height reduction of 32% at 160 ppm. Coreopsis grandiflora `Sunray', Rudbeckia fulgida var. Sullivantii `Goldsturm' and Monarda didyma `Blue Stocking' responded significantly to Sumagic with 30% to 60% height reductions at 4 WAT, but no persistent effects at 8 WAP. Height of Veronica alpine `Goodness Grows' was reduced 32% to 68% at 4 WAT, but all Sumagic rates resulted in persistent reductions in plant height at 12 WAP. Plant height of Alcea rosea mix and Echinacea purpurea were excessively reduced (up to 79%) at 4 WAT, but there were no persistent effects on height of Alcea in the landscape. All rates of Sumagic resulted in persistent reductions in height of Echinacea at 8 WAP, but only plants treated with 120 and 160 ppm Sumagic were still significantly shorter than controls at 12 WAP
The SFA Arboretum: The First Ten Years
Authors: Creech David L.
Published: February 2019

The SFA Arboretum is evidence that small horticulture programs can capitalize on what's right outside the back door of the building. Initiated in 1985 as a lab project in a landscape plant materials course on the south side of the Agriculture building, the collection has grown to over 3000 taxa displayed in a ten-acre public garden setting. The Arboretum's mission is to 1) promote the conservation and use of native plants, 2) evaluate “new” landscape plant materials, and 3) serve as a living laboratory for students in Horticulture, Agriculture, Biology and Forestry. Funding improvements in the last two years and the creation of a Board of Advisors and a Volunteer Corps organization has addressed problems in routine landscape maintenance and getting “new” garden developments off the ground. A “Plants with Promise” program acquires, tests, propagates, distributes and promotes superior “new” woody plants. Outstanding performers include Bignonia capreolata 'atrosangainea', Campsis grandiflora, Cinnamomum chekingensis, Euschapis japonica, Scuttelaria suffretescens 'pink', Sinojackia rehderiana, Taxodium mucronatum, Viburnum propinquum, various Styrax species and varieties, several Michelia species, Illicium henryi, three Mexico oaks, and many others. AutoCAD maps and a plant inventory database tracks plant location and acquisition data. A just-completed GIS-based analysis of the university forest paves the way for a campus-as-arboretum effort. The premise of this paper is that high-visibility, easy-access display/evaluation gardens offer Horticulture Departments the opportunity for enhanced student recruitment, community involvement, external funding, environmental education, and the potential for significant contributions to the nursery industry.
Storage Life of a Midseason Peach Held at 5 °C
Authors: Perkins-Veazie P. , Roe N. , Lasswell J. , McFarland J.
Published: February 2019

Growers in north and central Texas produce peaches of exceptional size and quality yet have no information on the best maturity stage/storage regime for maximum shelf life. `Majestic' peaches were harvested at five maturity stages, corresponding to hard green through full red, soft ripeness. Intermittent warming and/or delayed warming reduces chilling injury in peaches and these treatments were used on hard green through firm red stages. Fruit were held 4 weeks at 5 °C, 85% RH continuously (control); 1 day at 20 °C followed by 4 weeks at 5 °C (DS); 4 weeks at 5 °C with 1 day warming at 20 °C every 2 weeks (IW). Chilling injury symptoms (internal browning) were noted on control and IW peaches after 2 weeks storage. We concluded that hard green peaches are too immature and red peaches at velvet and full soft stages are too soft (<20N flesh resistance) to ship. Chilling injury appeared in peaches after 2 weeks storage at 5 °C but could be avoided by delaying storage for 24 hours after harvest.
Many Fresh-market Tomato Growers in the Southeastern U.S. Use IPM
Authors: Kemble J.M. , Bauske E. , Sikora E. , Zehnder G.
Published: February 2019

IPM teams from Alabama, North Florida, Georgia, Kentucky, North Carolina, South Carolina, and Tennessee composed of growers, private consultants, and faculty defined IPM on fresh-market tomatoes and created a survey from this definition to evaluate the level of IPM used by growers in the southeastern U.S. The survey included three sections: cultural practices, pesticide application techniques, and specific pest management practices, and was distributed to tomato growers in the region by mail, at county meetings, and through other relevant venues. Additionally, growers were asked to identify problems (insect, disease, and nonpest, i.e., cultural) and beneficial technology or research developments. Results of the survey revealed that in North Florida, Georgia, Kentucky, North Carolina, and South Carolina more than 75% of the tomato acreage is in the medium or high IPM category. These states have met or exceeded the State IPM teams' criteria for practicing IPM and have met the Federal mandate of IPM implementation on 75% of the fresh-market tomato cropland. Tomato producers listed early blight, late blight and bacterial spot as their main disease problems; tomato fruit worm, thrips, and aphids as their primary insect problems; and poor weather conditions, government regulation, and labor issues as their primary nonpest problems. Producers throughout the region felt that the development of resistant varieties would help them increase production the most. The State IPM teams outlined a clear definition of IPM in fresh-market tomato production and the survey results established a baseline that can be used to measure the success of programs to increase IPM adoption. The results will aid in focusing the Extension/research agenda in the universities in the Southeast.
Effect of Temperature Preconditioning on Free Radical Scavenging Enzymes in Chilling-tolerant and Chilling-sensitive Tomato Fruit
Authors: Aynaou R. , Woods F.M. , Shewfelt R. , Brown J.E. , Tuzun S. , Cherry J.H. , Sanders L.G.
Published: February 2019

The ability of two tomato cultivars, Lycopersicon esculentum cv. VFNTCherry (chill sensitive) and L. esculentum × L. pimpinellifollim cv. New York 280 (chill tolerant) to acclimate to low temperature storage at 2 °C were compared following prior temperature preconditioning. The activities of catalase, peroxidase, and superoxide dismutase and electrolyte leakage were monitored during a 15-day preconditioning period. Low temperature preconditioning reduced membrane damage in both fruit. In contrast, high temperature preconditioning accelerated the rate of leakage in VFNT, while fruit of NY 280 remained relatively undamaged. Low temperature preconditioning stimulated a 4-fold increase in catalase and peroxidase activities in fruit of NY280. High-temperature preconditioning appeared only to benefit fruit of NY280. Regardless of pretreatment, no significant change in superoxide dismutase activities were observed for either cultivar. These findings suggest that the ability to acclimate to low temperature stress may correlate with increased levels of catalase and peroxidase.
Cultivar and Maturity Effects on Color and Chemical Composition of Strawberry Fruit
Authors: Alleyne Victorine , Moore James N. , Murphy J. Brad
Published: February 2019

The color and chemical composition of three strawberry (Fragaria ×ananassa Duchesne) cultivars, `Arking', `Cardinal', and Earliglow' and one advanced selection, A-7383, were examined at four maturity stages in a 2-year study. Cultivar- and maturity-related differences were observed in CIELAB color space coordinates, L*, a*, b*, anthocyanin concentration, percent soluble solids; pH, titratable acidity, sugar/acid ratio, and total solids, insoluble solids, fructose, and sucrose content. No cultivar effect was detected for glucose concentration. `Arking' and `Cardinal' had the most intense red color and were similar in L*, a*, b* values, titratable acidity, and the concentration of anthocyanin, soluble solids, total solids, and fructose. They differed significantly in pH, sugar/acid ratio, and insoluble solids. A-7383 and `Earliglow' exhibited differences in all measured characteristics except total solids. A-7383 fruits contained the lowest anthocyanin concentration and were the darkest and least red of the genotypes.
Response of Young Papaya Plants to Nitrogen, Phosphorus, and Potassium Supply
Authors: Santos Bielinski M. , Morales-Payan Jose P.
Published: February 2019

Studies were conducted in the Dominican Republic to determine the short-term response of young `Cartagena Ombligua' papaya (Carica papaya) plants to nitrogen (N), phosphorus (P), and potassium (K) fertilization. N, P2O5, K2O were individually applied 20 days after transplanting at rates 0, 6, 12, 18, and 24 g per plant. Plant height, stem diameter, leaf area, and root and shoot dry weight responded to N and K in a quadratic fashion (N:Y= 30.79+ 1.35X-0.07X2; K20:Y = 30.02 +1.6X - 0.06X2). Maximum growth was obtained with 6 and 18 g of N and K2O, respectively. P fertilization did not significantly affect shoot growth, but it stimulated root growth (Y = 2.02 + 0.41X - 0.013X2).
Growth Analysis of Tomatoes in Black Polyethylene and Hairy Vetch Production Systems
Authors: Teasdale John R. , Abdul-Baki Aref A.
Published: February 2019

Growth analysis was used to document growth responses of staked, fresh-market tomatoes (Lycopersicon esculentum Mill.) to black polyethylene or hairy vetch (Vicia villosa Roth) mulches. Leaf area and dry mass of vegetation and fruit were measured weekly during two growing seasons. Growth was better early in the season but worse later in the season for plants grown with black polyethylene than with hairy vetch mulch. Unit leaf rate (rate of growth per unit leaf area) of fruit was higher with black polyethylene than with hairy vetch, whereas the reverse was true of vegetation. This relationship led to a higher leaf area ratio and leaf area duration of plants grown with hairy vetch than with black polyethylene. Consequently, tomatoes grown with black polyethylene produced higher early yield because of increased partitioning to fruit. However, tomatoes grown with hairy vetch eventually outgrew and outyielded those grown with black polyethylene because of increased partitioning to leaf area.
Postharvest Quality of Cut Roses Following Electron-beam Irradiation
Authors: Chang Ai-Yu , Gladon Richard J. , Gleason Mark L. , Parker Sharon K. , Agnew Nancy H. , Olson Dennis G.
Published: February 2019

Cut Rosa ×hybrida L. `Royalty' flowers were used to determine the efficacy of electron-beam irradiation for increasing postharvest quality and decreasing petal infection by Botrytis cinerea Pers. In an experiment for determining the injury threshold, roses received electron-beam irradiation of 0, 0.5, 1, 2, and 4 kGy. Irradiation dosages ≥1 kGy caused necrosis on petal tissue and decreased postharvest life at 20 °C. In a second experiment to evaluate postharvest quality, roses were irradiated at 0, 0.25, 0.5, 0.75, and 1 kGy. Dosages of 0.25 and 0.5 kGy slowed the rate of flower bud opening for 2 days but did not decrease postharvest quality when compared with nonirradiated roses. Roses that received irradiation dosages of 0.75 and 1 kGy showed unacceptable quality. In a third experiment, roses that had or had not been inoculated with B. cinerea were irradiated at 0, 0.25, 0.5, and 0.75 kGy. Irradiation did not control B. cinerea populations, and rose quality decreased as dosage increased. In a fourth experiment to determine the effect of irradiation on B. cinerea, conidia on water-agar plates exposed to dosages ≤1, 2, and 4 kGy germinated at rates of ≈90%, 33%, and 2%, respectively, within 24 h.
Bulb Quality and Traumatic Acid Influence Bulblet Formation from Scaling in Lilium Species and Hybrids
Authors: Marinangeli Pablo , Curvetto Néstor
Published: February 2019

Scaling is a common commercial technique to propagate Lilium. The present research work evaluated the impact of genotype, traumatic acid (TA), and initial bulb quality on bulblet production by scaling propagation. Genotypes used were: L. longiflorum Thunb. `Snow Queen', L. lancifolium Thunb., one Oriental hybrid (L. × `Stargazer'), and four Asiatic hybrids (L. × `Enchantment', L. × `Connecticut King', L. × `Sunray', L. × `Cote d'Azur'). The genotypes showed a wide variability in the number (1.1-2.6 bulblets per scale) and biomass (83-295 mg per bulblet) of bulblet production. The same variability was exhibited after treatment with TA, which produced an increase of 20% to 40% in the number of bulblets per scale and also a significant increase in their fresh mass (20% to 60%). Using poor quality L. × `Cote d'Azur' bulbs adversely affected the biomass and number of bulblets produced on the scales, and this effect was not overcome with TA treatment. Chemical name used: 10(E) dodeca-l,12-dicarboxylic acid (traumatic acid).
Broccoli Production in Forage Soybean and Foxtail Millet Cover Crop Mulches
Authors: Abdul-Baki Aref A. , Morse Ronald D. , Devine Thomas E. , Teasdale John R.
Published: February 2019

`Emperor' broccoli (Brassica oleraceae L. Botrytis Group) was grown in Fall 1995 at the Beltsville Agricultural Research Center (BARC), Md., and at the Kentland Agricultural Research Farm (KARF), Virginia Polytechnic Institute and State Univ., Blacksburg. The objectives were to determine the effects of cover crop mulches in no-tillage production systems on marketable broccoli yield and weed suppression. The mulch treatments included cover crops of forage soybean (Glycine max L.), foxtail millet (Setaria italica L.P. Beauv), and a combination of soybean and millet. Broccoli marketable yield from all three mulch treatments was equal to that from a conventional clean cultivation system, except for the millet treatment at BARC, which produced a lower yield. All treatments maintained weeds below levels that reduced yield. Cover crop biomass ranged from 4.6 to 9.6 t·ha-1 and N content from 10 g·kg-1 for millet to 28 g·kg-1 for soybean.
Collard—Cowpea Intercrop Response to Nitrogen Fertilization, Redroot Pigweed Density, and Collard Harvest Frequency
Authors: Itulya Francis M. , Mwaja Vasey N. , Masiunas John B.
Published: February 2019

Field experiments were conducted in 1992 and 1993 to determine the effect of N fertility, cropping system, redroot pigweed (Amaranthus retroflexus L.) density, and harvesting frequency on collard (Brassica oleracea var. acephala D.C) and cowpea [Vigna unguiculata (L.) Walp.] growth. The N fertilization regimes were 0, 80, 160, and 240 kg·ha-1, applied as urea in a split application. Four weeks after crop planting, redroot pigweed was seeded at 0, 300, and 1200 seeds/m2. Between weeks 6 and 12, collard leaves were harvested at 1- to 3-week intervals. Year, N fertility, and cropping system interacted to determine collard leaf number and mass. For example, in 1992, with N at 160 kg·ha-1, collards intercropped had more total leaf mass than those monocropped. Pigweed density had no effect on collard yields, which were greatest from the 3-week harvest frequency. Cropping system and pigweed density interacted to determine cowpea vine length, shoot dry mass, and branching. The high density of pigweed caused a 56% reduction of cowpea dry mass in 1992.
Changes in Spray Retention by Apple Leaves during a Growing Season
Authors: Hall Franklin R. , Downer Roger A. , Cooper Jane A. , Ebert Timothy A. , Ferree David C.
Published: February 2019

Apple (Malus domestica Borkh.) leaves were sprayed to runoff using a selection of pesticides, and subsequent spray retention was evaluated by weight. Timing, cultivar, leaf surface, and leaf type significantly influenced spray retention. Spray retention correlated significantly and positively with leaf hair density. The importance of these differences is considered in relation to the possible efficiency of the pesticide application process in apple orchards.
Mixtures of Cucumber Cultigens Affect Yield in a Multiple-harvest System
Authors: Schultheis Jonathan R. , Wehner Todd C. , Walters S. Alan
Published: February 2019

Seeds of cucumber (Cucumis sativus L.) cultigens were mixed and compared for fruit yield (Mg·ha-1) and crop value ($/ha). Three cultigen pairs (Gy 14A + M 21, Gy 4 + WI 2757, and `Regal' + `Carolina') and five component ratios of each cultigen pair (0:100, 25:75, 50:50,75:25, and 100:0) were evaluated in five plantings over a 3-year period. Fruits were harvested six to eight times for each planting date. Early and total fruit yields and crop values were greatest when either Gy 14A or Gy 4 were planted as pure stands. As the ratio of Gy 14A or Gy 4 increased in the seed mixture, the yield and crop value increased. However, when the two predominantly gynoecious hybrids, `Regal' and `Carolina', were mixed, the yield and crop value were greater than those of pure stands of either hybrid. The combination of 75% `Regal' and 25% `Carolina' resulted in higher early and total fruit yields and crop value than the other ratios of the same cultigen pair. The `Regal' + `Carolina' pair produced significantly higher early yield and early crop value (first two harvests) than did the other cultigen pairs tested. However, total yield and total value for `Regal' + `Carolina' did not differ from the Gy 14A + M 21 pair. The practice of mixing two cultivars in arbitrary combinations does not offer an advantage over single cultivars in a multiple-harvest system. In some cases, predominantly gynoecious-predominantly gynoecious mixtures may have advantages over monoecious-predominantly gynoecious cultigen mixtures if pollination is not limiting. Seed mixtures need to be evaluated to determine whether specific combinations offer advantages, as this study indicated that superior mixtures may exist.
Reproductive and Vegetative Characteristics of Pecan Cultivars
Authors: Wood Bruce W. , Smith Morris W. , Worley Ray E. , Anderson Peter C. , Thompson Tommy T. , Grauke L.J.
Published: February 2019

Staminate and pistillate flower maturity of 80 cultivars of young (<15 years old) pecan [Carya illinoinensis (Wangenh.) K. Koch] trees are presented. These patterns show that pollination and receptivity windows within the flowering season can be divided into very early, early, mid, late, and very late season protandrous (Type I) and protogynous (Type II) types. This system therefore provides a seasonally based 30-class Type I and Type II alternative to the standard two-class Type I and Type II system, thus offering enhanced resolution of flowering intervals and an improved means of selecting cultivars to ensure cross-pollination of yard and orchard trees. Scott-Knott cluster analysis of budbreak, nut ripening date, and date of autumn leaf drop segregated cultivars into one of several categories.
Stem Flow, Throughfall, and Canopy Interception of Rainfall by Citrus Tree Canopies
Authors: Li Y.C. , Alva A.K. , Calvert D.V. , Zhang M.
Published: February 2019

It is generally believed that the interception of rain by the citrus tree canopy can substantially decrease the throughfall under the canopy as compared to that along the dripline or outside the canopy (incident rainfall). Therefore, the position of placement of soil-applied agrichemicals in relation to the tree canopy may be an important consideration to minimize their leaching during rain events. In this study, the distributions of rainfall under the tree canopies of three citrus cultivars, `Marsh' grapefruit (Citrus paradisi Macf.), `Hamlin' orange (Citrus sinensis L. Osbeck), and `Temple' orange (Citrus hybrid), were evaluated at four directions (north, south, east, west), two positions (dripline and under the canopy), and stem flow. There was not a significant canopy effect on rainfall amounts from stem flow or dripline, compared with outside canopy, for any citrus cultivar or storm event. However, throughfall varied significantly among the four cardinal directions under the canopy of all three citrus cultivars and was highly related to the wind direction. Among the three citrus cultivars evaluated in this study, throughfall, stem flow, and canopy interception accounted for 89.5% to 92.7%, 0.5% to 4.7%, and 5.8% to 9.3% of the incident rainfall, respectively.
Matric Priming of Kentucky Bluegrass and Tall Fescue Seeds Benefits Seedling Emergence
Authors: Pill Wallace G. , Frett John J. , Williams Ian H.
Published: February 2019

Matrically priming seeds of common Kentucky bluegrass (Poa pratensis L.) and `SR8300' tall fescue (Festuca arundinacea Schreb.) in fine, exfoliated vermiculite (-1.5 MPa, 20 °C, 4 days) increased subsequent germination rate but did not increase germination percentage or synchrony. The lowest seed: vermiculite ratio (dry weight basis) to provide full priming benefit for seeds of Kentucky bluegrass and tall fescue was 1:10 and 1:20, respectively. Storing Kentucky bluegrass seeds primed in 1:10 (seed:vermiculite) in moist vermiculite for 10 days at either 5 or 20 °C did not reduce germination rate in comparison to primed seeds that were not stored. Primed tall fescue seeds could be stored in moist vermiculite (1:20, seed:vermiculite) for up to 10 days at 5 °C with no loss of priming benefit, but storage for only 2 days at 20 °C resulted in germination. Primed seeds of Kentucky bluegrass (stored for 0 or 10 days at 5 or 20 °C) or tall fescue (stored 0 or 10 days at 5 °C or 2 days at 20 °C) resulted in more rapid germination and seedling emergence, and greater seedling shoot fresh and dry masses than was the case for nonprimed seeds.
Genotypic Differentiation in Temperature Requirements for Stratification in Subtropical Peach Seeds
Authors: Pérez-González S.
Published: February 2019

The variability of species under local ecosystems, particularly in response to temperatures during endodormancy, permits adaptation of temperate fruit trees to subtropical climates. Information about the behavior of endodormant fruit trees and seeds is based on a narrow genetic base from higher latitudes. This work was conducted to generate information about responses of endodormant seeds from several subtropical peach (Prunus persica L.) genotypes, as a basis for breeding and selection in these regions. Samples of peach seeds were collected from genotypes originating at a range of altitudes in tropical-subtropical regions to evaluate their responses to different temperatures and lengths of stratification periods. When seeds were stratified at 7 °C, some genotypes with very low-chilling requirement registered a high percent germination in <40 days, and all accessions studied reached 95% germination before day 80. When seeds were stratified at warmer temperatures (10 and 14 °C), germination started earlier and was high at 10 °C for most accessions. Although seeds of some late-blooming accessions germinated earlier at 10 or 14 °C than at 7 °C, percent germination was lower and time-response curves were flatter. This contrasts with previous reports on genotypes with high-chilling requirement, where no germination was registered at 14 °C. These observations provide a background for screening seedlings for adaptation to local conditions, and suggest that endodormancy models should be based on information generated from local genotypes when applied in subtropical regions.
Ethylene Production by `d' Anjou' Pears during Storage at Chilling and Nonchilling Temperature
Authors: Gerasopoulos D. , Richardson D.G.
Published: February 2019

To determine the ability of `d' Anjou' pear fruit to produce climacteric ethylene postharvest, fruit were harvested at a mature green stage, chilled at -1 °C for various times, then transferred to 20 °C to ripen. In addition, fruit were first held at 20 °C for various times, then at –1 °C for various durations, followed by transfer to 20 °C for 11 days. As storage time at –1 °C increased from 0 to 70 days, the time required to induce climacteric ethylene when transferred to 20 °C progressively decreased from 90 to 0 days. The total storage time (sum of d at chilling and nonchilling temperature) needed to induce climacteric ethylene remained nearly constant (70 to 90 days). However, this was not the case with fruit held initially at 20 °C, then transferred to –1 °C. The total storage time needed before the pears produced climacteric ethylene ranged from 70 to 110 days and increased with time of storage at 20 °C. These fruit required more time at –1 °C than those first stored at –1 °C. The chilling requirement mechanism of `d' Anjou' pears remains intact even during storage at nonchilling temperature and diminishes with senescence.
RAPD Marker Polymorphism among Saskatoon Cultivars, Clones, and Seedlings
Authors: Weir B.J. , Pierre R.G. St. , Chibbar R.N.
Published: February 2019

Randomly amplified polymorphic DNA (RAPD) markers were used to distinguish among 16 cultivars of saskatoon (Amelanchier spp.). Eight 9-base, oligonucleotide primers amplified a total of 98 DNA fragments, of which 29 were useful as reproducible polymorphic markers. Twelve cultivars and two pairs of cultivars were uniquely characterized by these 29 markers. Polymorphism was not detected among five sources of the cv. Thiessen, whereas variability was found among seedlings from self-pollinated `Thiessen'. Samples of the cvs. Regent and Parkhill were indistinguishable from one of two sources, suggesting that the cultivars were mislabelled.
The Role of Librarians in Agricultural Global Information Systems for Decision Support
Authors: Matylonek John
Published: February 2019

Anyone who has had an occupation that uses the personal computer can attest to the way the tool affects the fundamental way in which tasks are done. It's this qualitative nature of the changes—not whether the computer makes your work more productive or more efficient—that really is the central finding of the research of information technology and organizations. Of people in all occupations, those who deal with information as the main product and service find themselves in a peculiar position. Because the tool itself is also the product, every change in technology reorders tasks and procedures so that the new system is accommodated. Given enough incremental change in the way information is manipulated, the core skill set of the practitioner must necessarily change. This puts a strain on the legacy systems, both social and technical, they leave behind. Librarianship is one profession whose central skill set is being challenged by the march of progress in information technology. This paper examines the way some librarians have shifted emphasis of their core skill set to meet the challenge of remaining relevant within the new information infrastructure. It will then examine the ramifications of the adaptation on the customers that they serve, the legacy organizational protocol, and the administrative bureaucracies they have been managed by.
Electronic Access, Design Issues, and Publishing Research Information on the World Wide Web
Authors: Starr Karen
Published: February 2019

Traditionally, researchers have obtained published information in the form of journal articles, often using indexing tools like Biologica Abstracts to find a particular topic. Articles were indexed, coded, an abstracted so that people could find the information they needed in an organized fashion. Much of what is currently being published on th World Wide Web uses traditional paper publishing techniques overlain with lots of graphics designed to fit the needs of the MTV generation. Should we be publishing quality research information on the web? What research information should be published? What information design criteria do we use? Moreover, how do we design information for effective use and retrieval given the inherent nature of the web and the lack of sophistication in the currently available Internet search retrieval engines? What are the information management issues with which we must deal if we are to make publicly funded research information available to other researchers and to the American public?
Simulation of Ecological and Evolutionary Interactions of Darwin's Finches—A Multimedia Learning Tool
Authors: Quinn R.D.
Published: February 2019

Dr. Quinn is one of a team of six biology professors from six different CSU campuses collaborating on this pilot project. EvolvelT is a web-based method for students to learn the fundamentals of natural selection and speciation by simulating natural processes. The simulation will be modeled on the evolution of Darwin's Finches in the Galapagos Islands. Learners will manipulate variables such as initial population size, variability and heritability of bill morphology, and quantity and quality of seeds, and then observe changes with time in population size and bill morphology. The interactive model will allow variables to be changed and simulations to be repeated, producing results that can be graphed and statistically analyzed. The Integrated Technology Strategy (ITS) of the California State University System (CSU) is using the Internet to create new and more flexible learning opportunities. Recently the ITS brought together biologists from several CSU campuses to explore ways to use technology to improve learning in introductory biology laboratories for non-science students. These laboratories were chosen because they affect large numbers of students at all campuses. Development criteria include applicability across the CSU, improvement in learning quality, accessibility to large numbers of students, and measurable success. We selected evolution as a topic for web-based learning because it is a central concept of biology, and it is relatively difficult to teach in conventional introductory biology laboratories. Our development team will work with multimedia design specialists to insure that the web presentation promotes scientifically sound and efficient learning. We are collaborating via e-mail and occasional video conferences and face-to-face meetings. We will work on the actual teaching materials via a web page. The initial prototype will be ready by early summer 1997 and will be tested, modified, and released for beta testing by summer's end.
Response of Young Blueberry Plants to Irrigation in Florida
Authors: Haman D.Z. , Smajstrla A.G. , Pritchard R.T. , Lyrene P.M.
Published: February 2019

Two-year-old, container-grown rabbiteye (Vaccinium ashei Reade) and high-bush (Vaccinium corymbosum L.) blueberry plants were used in a 3-year study of water requirement for blueberry production in Florida. The rabbiteye cultivars Powderblue and Premier and the highbush cultivar Sharpblue were grown under three irrigation regimes. Irrigation events were triggered when soil water tensions in the upper 15 cm of the containers reached either 10, 15, or 20 kPa. Neither yield nor vegetative growth of rabbiteye cultivars differed among treatments. During the third year, the growth increase in highbush blueberry was significantly greater in the 10-kPa than in the 15- and 20-kPa treatments. The highest water treatment (10 kPa) resulted in a significant yield increase for the highbush cultivar.
Container Medium and Nitrogen Form Affect Production of Amur Maackia (Maackia amurensis Rupr. & Maxim.)
Authors: Aiello Anthony S. , Graves William R.
Published: February 2019

Amur maackia (Maackia amurensis Rupr. & Maxim.) has potential as a more widely grown nursery crop, but little information is available on effects of media and nutrition on growth of containerized plants. We compared growth of seedlings in five media and determined growth responses to two fertility regimes. After 35 days, total dry mass of plants grown in 1 perlite: 1 vermiculite (by volume) or in 5 sphagnum peat: 3 perlite: 2 soil was 3.2 times the dry mass of plants grown in three soilless media that contained composted bark; and after 70 days, growth was greater in the medium with soil than in 1 perlite: 1 vermiculite. Plants grown in solution culture with N at 0.75 mm had 1.8 times the dry mass of those provided N at 3.75 mm. Form of N in solution did not affect dry mass, but N content of leaves of plants grown with >50% was 1.3 times as great as that of plants provided only . Plants in containers attained maximal dry mass when fertilized with solutions containing N at 10.8 mm from , , and urea or N at 7.5 mm with equal amounts of and . None of the soilless media used consistently evoked growth similar to growth of plants in the soil-based medium.
Controlled Atmosphere and Antioxidant Effects on External CO2 Injury of `Empire' Apples
Authors: Watkins C.B. , Silsby K.J. , Goffinet M.C.
Published: February 2019

The histology of external CO2 injury of the skin of `Empire' apples and postharvest factors affecting occurrence of injury were investigated. Injury was greater in a 5% CO2/2% O2 atmosphere than in 2% CO2/2% O2, but incidence was affected by orchard source. Susceptibility to injury was highest during the first 4 weeks of storage, while a postharvest treatment with diphenylamine prevented the disorder. Ethanol reduced injury, but ascorbic acid increased incidence of the disorder. Keeping fruit in air cold storage for 10 days before application of CO2 markedly reduced incidence of CO2 injury. Histological studies showed that external CO2 injury begins at the hypodermis—cortex boundary and spreads outward into the upper hypodermis and inward into outer cortex cells, although the cuticle and epidermis appear unaffected and unbroken. Radial walls of affected cells collapse and become pleated, so that the skin surface sinks below nearby normal regions. Other cellular events include loss of cytoplasmic integrity, coagulation of the protoplast, loss of organelle structure, and cell wall separation. Nondigested starch can be found in cells of affected fruit at the hypodermis—cortex boundary. We conclude that several factors affect fruit susceptibility to CO2 injury, including orchard, antioxidant treatment, and delays before application of CO2.
Establishment in Treeshelters I: Shelters Reduce Growth, Water Use, and Hardiness, but not Drought Avoidance
Authors: Kjelgren Roger , Rupp Larry A.
Published: February 2019

We investigated water use and potential drought avoidance of Norway maple (Acer platanoides L.) and green ash (Fraxinus pennsylvanica Marsh) seedlings grown in protective plastic shelters. Gravimetric tree water use and reference evapotranspiration for fescue turf (ETo) were monitored for 1 to 3 days during the growing season. Water use of trees was 8% to 14% of ETo in shelters vs. 29% to 40% for trees not in shelters. Trunk diameter was affected more than whole-tree water relations by lack of irrigation, suggesting that the nonirrigated trees were subjected to only mild water stress. Shelters did not improve drought avoidance, as water potentials were generally more negative and trunk diameter increment was lower for nonirrigated trees in shelters. Maples in shelters were affected more adversely by lack of water than were ash. Higher temperatures in shelters also may have reduced trunk growth. Air temperatures were 13 °C warmer than ambient in nonirrigated shelters, but only 5 °C warmer in irrigated shelters. Tree shelters can reduce transpiration rates by over half, but benefits from reduced water loss may be offset by negative effects of higher air temperatures. Shelters reduced cold hardiness of both species, but maple was affected more than ash.
Changes in External and Internal Quality Characteristics of Three Tomato Cultivars Grown at Seven Different Sowing Seasons
Authors: Islam Md. Shahidul , Khan S. , Hossain S.M.M.
Published: February 2019

Seasonal fluctuations of the physical and biochemical characteristics of three tomatoes, including two large-fruited and one cherry-fruited cultivars, were studied in seven different sowing time at an interval of 45 days. Seasonal variation were noted in the external and internal quality characteristics. The seasonal pattern of ripening exhibited a rapid first ripening during summer, followed by a progressive decline until the winter season. Fruits picked during early winter to spring had higher constituents compared to summer season. The fruits matured during the summer season showed higher accumulation of organic and ascorbic acid; but the crop duration was found to be shortened. On the other hand, the fruits matured during winter to spring season had higher firmness, soluble sugars and longer growing period. The lycopene synthesis was enhanced during spring to winter seasons. Of the climatic factors recorded, temperature is predominantly implicated in affecting tomato fruit quality. The results indicated that, firmness, total soluble solids and turning point of hue (arctan a*/b*) act as the indicators of fruit maturity, and breaker stage is more appropriate stage of harvesting in all the seasons studied. But regarding nutritional value and appearance, and for fresh consumption, pink stage of ripening is the best for harvesting. In the present study, although cropping season and growing temperature differed widely, but the cumulative temperature (°C day; from flowering to maturation) difference among growing seasons was small, and most suitable harvest period was found to be around 1000 °C day. Thus, for consumption, marketing and transportation, the fruits availing around 1000 °C days cumulative temperature are congenial to be harvested.
Inhibition of Fungal Growth by Macerated Plant Tissues in a Closed Environment
Authors: Charron Craig S. , Chardonnet Catherine O. , Sams Carl E.
Published: February 2019

The U.S. Clean Air Act bans the use of methyl bromide after 2001. Consequently, the development of alternative methods for control of soilborne pathogens is imperative. One alternative is to exploit the pesticidal properties of macerated tissues of Brassica spp. This study tested the potential of several Brassica spp. for control of fungal pathogens. Pythium ultimum Trow or Rhizoctonia solani Kühn plugs on potato-dextrose agar on petri dishes were sealed in 500-ml glass jars (at 22 °C) containing macerated leaves (10 g) from one of six Brassica spp. Radial growth was measured 24, 48, and 72 h after inoculation. Indian mustard (B. juncea) was the most suppressive, followed by `Florida Broadleaf' mustard (B. juncea). Volatile compounds in the jars were sampled with a solid-phase microextraction device (SPME) and identified by gas chromatography-mass spectrometry (GC-MS). Allyl isothiocyanate (AITC) comprised over 90% of the total volatiles measured from Indian mustard and `Florida Broadleaf' mustard. Isothiocyanates were detected in jars with all plants except broccoli. (Z)-3-hexenyl acetate was emitted by all plants and was the predominant volatile of `Premium Crop' broccoli (B. oleracea L. var. italica), `Michihili Jade Pagoda' Chinese cabbage (B. pekinensis), `Charmant' cabbage (B. oleracea L. var. capitata), and `Blue Scotch Curled' kale (B. oleracea L. var. viridis). To assess the influence of AITC on radial growth of P. ultimum and R. solani, AITC was added to jars to give headspace concentrations of 0.10, 0.20, and 0.30 mg·L–1 (mass of AITC per volume of headspace). Growth of both fungi was inhibited by 0.10 mg·L–1 AITC. 0.20 mg·L–1 AITC was fungicidal to P. ultimum although the highest AITC level tested (0.30 mg·L–1) did not terminate R. solani growth. These results indicate that residues from some Brassica spp. may be a viable part of a soilborne pest control strategy.