bluuebunny/crossref_metadata_2025 huggingface dataset:
Salinity Effects on Bud Yield and Vegetative Growth of Artichoke (Cynara scolymus L.)
Authors: Francois Leland E.
Published: February 2019

Globe artichokes recently have been planted in the irrigated desert area of southern California. Soils in this area are, or have the potential to become, highly saline from the application of saline irrigation water. Thus, a 2-year field plot study was conducted. A control and five saline treatments were imposed by irrigation with waters that contained equal weights of NaCl and CaCl. Bud yield and vegetative growth were measured. For the two years, relative bud yield was unaffected up to a soil salinity of 6.1 dS·m [electrical conductivity of the saturated soil extract (EC,)]. Each unit increase in salinity above 6.1 dS·m reduced yield by 11.5%. These results place artichoke in the moderately salt-tolerant category. Yield reduction was attributed primarily to reduced bud weight rather than bud count. Vegetative growth was more tolerant to salt stress than was bud production. Chloride concentration in midrib and blade tissue increased as salinity increased.
GIBBERELLIC ACID DURING PRIMING OF PURPLE CONEFLOWER [ECHINACEA PURPUREA (L) MOENCH.] SEEDS IMPROVES GERMINATION AND SEEDLING EMERGENCE
Authors: Haynes Janine O. , Pill Wallace G.
Published: February 2019

Purple coneflower seeds following priming (-0.04 MPa, 10 days, 15C, darkness) osmotically in polyethylene glycol 8000 (PEG) or matrically in expanded no. 5 vermiculite had greater germination rate and synchrony at continuous 20C or 30C than untreated seeds, but germination percentage was unaffected. Inclusion of 5.5 × 10-2 M gibberellic acid (GA3 as ProGibb Plus 2X, Abbott Laboratories, N. Chicago, Ill.) further improved germination rate and synchrony at 20C, but not at 30C. In a greenhouse study (30C day/27C night, July-August natural light), seeds primed in PEG or vermiculite containing G A3 compared to untreated seeds had 6 percentage points higher maximum emergence (ME), 3.3 fewer days to 50% ME, 1.9 fewer days between 10% and 90% ME, 116% greater shoot dry weight, and 125% longer leaves at 16 days after planting in peat-lite. Inclusion of ethephon (0.01 m, as Florel) either alone or with GA3 during priming provided no benefit to seed germination or seedling emergence. Moistened vermiculite substituted for PEG solution as a priming medium for purple coneflower seeds, the priming benefit on seedling emergence and growth being enhanced by 5.5 × 10-2m G A3 inclusion in the priming media.
COMPARISON OF RAPD MARKERS BETWEEN HEAT-TOLERANT AND INTOLERANT CULTIVARS OF LIMA BEANS
Authors: Kleiner Kathryn R. , Frett John J. , Nienhuis James
Published: February 2019

Lima beans are an important vegetable crop to the processing industry in Delaware, but yields in Delaware are below other areas due to heat. The objective was to correlate RAPD markers from heat-tolerant and intolerant cultivars with phenotypic data. Twenty-five primers were used, 10 of which generated 25 polymorphic bands among 11 cultivars. MDS analysis of genetic distance among the cultivars shows segregation into two major clusters, with Kingston as a distant outlier. Kingston's position can be correlated to published data reporting its consistently good yields even when temperatures are high. The results of this study indicate RAPD markers may be used to screen for cultivars that have high yield potentials despite high temperatures. Further studies to screen F, and inbreeds will determine the usefulness of these markers in breeding programs.
MOSAIC: A MULTIMEDIA PLATFORM FOR TEACHING PLANT MATERIALS
Authors: Mackenzie Elizabeth O. , Erett John J.
Published: February 2019

A Mosaic tour of the Univ. of Delaware Botanic Gardens is available on Internet using the Mosaic server and provides fact sheets about herbaceous and woody plants. Each sheet is a mosaic page with in-lined images that include hyper-links to a sound file of the pronunciation of the Latin plant name and images of the plant, including buds, flowers, fruits, leaves, and other characteristics. A map of the garden identifying the plant's location is provided on each page to orient visitors and students. There are currently over 1500 images in development. The tour uses map images and key words to help students identify and select plants. Composite views illustrating the same characteristic from several plants provide a visual method to aid students in identification of unknown specimens. Database searches provide a method to search for plant information in the tour, and in the future will provide lists of plants with specific characteristics. The Mosaic Tour of the Univ. of Delaware Botanic Gardens can be accessed via URLS:http://bluehen.ags.udel.edu/ugarden.html.
INDUCTION OF CHILLING-TOLERANCE IN CUCUMBER (CUCUMIS SATIVUS L.) SEEDLINGS BY ENDOGENOUS AND APPLIED ETHANOL
Authors: Frenkel Chaim , Erez Amnon
Published: February 2019

Five-day-old etiolated cucumber (Cucumis sativus L. cv. Marketmore) seedlings held at 2C for 72 hours develop chilling injury resulting in desiccation and collapse of the hypocotyl tissues and eventual plant death. Hypoxia-induced accumulation of ethanol and acetaldehyde led to tolerance to subsequent chilling as evidenced by continued hypocotyl growth and freedom from injury. Arrest of volatile accumulation by applied bisulfite negated the development of hypoxia-induced chilling tolerance in seedlings. In seedlings held in normoxia, cold tolerance was induced by applied ethanol vapors, whereas acetaldehyde had a marginal effect, suggesting that hypoxia-induced cold tolerance may arise from the accumulation and activity of ethanol. Cold tolerance was induced by exposure to gaseous n-propanol and n-butanol vapors and other volatile anesthetics, including chloroform and halothane, indicating that ethanol activity may stem in part from an anesthetic effect that causes disorder of membrane lipids. However, development of cold tolerance in ethanol-enriched tissues was time-dependent, suggesting an association with biosynthetic event(s). Ethanol did not change the fatty acid composition in cucumber hypocotyl membranes.
CONTROL OF GREENHOUSE WHITEFLY (TRIALEURODES VAPORARIORUM) USING DELPHASTUS PUSILLUS AND AZATIN, A BOTANICAL INSECTICIDE
Authors: Maiuro Marie E.
Published: February 2019

Fifty greenhouse whitefly (Trialeurodes) were placed in each of 10, one-meter square nylon chiffon cages containing nine regal geraniums in 6-inch pots. After allowing the whitefly to reproduce for 2 weeks, the treatments tested were Delphastus pusillus alone, Azatin sprays alone, D. pusillus and Azatin together, and no control method. Two repetitions for each treatment were conducted. The Azatin, 14 oz/100 gallons, and a spreader/sticker were applied weekly with a mist sprayer. Delphastus pusillus, nine per cage, were released every 2 weeks. Sampling was conducted weekly by placing yellow sticky traps into each box for a 24-hour period, then counting the number of adults caught. All treatments gave statistically significant fewer whitefly than the cages with no control method. The cages with Azatin and/or D. pusillus were not statistically different from each other. Results indicate that D. pusillus can control whitefly as well as a growth regulator/botanical insecticide.
Crop Production, Growth, and Ultimate Size of Cactus Pear Fruit following Fruit Thinning
Authors: Inglese P. , Barbera G. , La Mantia T. , Portolano S.
Published: February 2019

We established a cladode load and thinning time that maximized fruit and flesh size in `Gialla' cactus pear (Opuntia ficus-indica Mill.). Five weeks after spring flush removal, second flush flower buds were thinned to nine, six, or three per cladode; the same treatment was repeated during the early stages of fruit development. Control cladodes had a natural load of 15 fruit. Time of thinning did not affect fruit growth and ultimate weight. Fruit and flesh weight increased with thinning, but export weight was obtained only in cladodes with no more than six fruit. Heavier thinning did not result in any further increase of fruit or flesh weight. Percent flesh was not affected by thinning. Fruit characteristics, such as total soluble solids concentration and seed content did not change with thinning, but the seeds: flesh ratio decreased with thinning. Fruit on cladodes with the lowest load ripened earlier than those on more heavily yielding cladodes.
Measuring Fruit Cell Size and Estimating Changes in the Number of Fruit Cells by Replica or Video Microscope
Authors: Sugiura T. , Honjo H. , Horimoto M.
Published: February 2019

Cell size in fruit flesh could be determined rapidly using a light microscope to inspect replicas obtained by pressing acetyl cellulose films or coatings on fruit flesh sections with nail polish. Alternatively, cell outlines in fruit sections stained with ink were observed directly using a video microscope. A test square drawn on a picture of cells was examined to rapidly evaluate mean cell size and the change in cell count.
Regeneration of Peach [Prunus persica (L.) Batsch] Rootstock Cultivars from Cotyledons of Mature Stored Seed
Authors: Pooler M.R. , Scorza R.
Published: February 2019

Shoots were regenerated from cotyledons of mature stored seed of three peach rootstock cultivars (`Flordaguard', `Nemared', and `Medaguard'). Shoot regeneration rates were highest when cotyledons were cultured for 3 weeks in darkness on Murashige and Skoog (MS) medium with 2.5% sucrose and a combination of IBA (1.25 or 2.5 μm) and TDZ (6.25 or 12.5 μm). Regeneration rates for `Flordaguard', `Nemared', and `Nemaguard' were as high as 60%, 33%, and 6%, respectively. Length of seed storage (1 to 3 years) did not affect regeneration rates. Seventy percent of regenerated shoots produced rooted plants. This regeneration method is rapid and simple, and stored seed can be used year-round. It may be a useful regeneration system for gene transfer in seed-propagated peach rootstocks. Chemical names used: 5 indole-3-butyric acid (IBA); thidiazuron (TDZ).
ALTERNATIVES IN MEDIA: FINDING RENEWABLE SUBSTITUTES FOR PEATMOSS
Authors: Newell LeAnne , Cole Janet C.
Published: February 2019

WetEarth, a processed recycled newspaper product, was used in combination with pine bark, sand, and vermiculite as a growing medium for rose of Sharon and forsythia. Rose of Sharon was taller and had more leaves; more leaf area per plant; and greater leaf, stem, and root dry weights in all media containing recycled paper compared to plants grown in a medium consisting of 3 pine bark: 1 peat moss: 1 sand (by volume) (control). Forsythia grown in the control media were taller than those grown in any medium containing recycled newspaper. There was no difference in number of leaves per plant or leaf area of forsythia, regardless of growing medium. Physical and chemical properties of each medium also were investigated. All media containing recycled newspaper had a higher pH, porosity, and air space than the control medium.
RHIZOBIUM COMPETITION IN ANTIGUAN SOILS: STRAIN ISOLATION
Authors: Marsh Dyremple B. , Marsh Lurline E. , Cooper Brian
Published: February 2019

The enzyme-linked immunosorbent assay was used to determine the competitive ability of three Rhizobium strains introduced into Antiguan soil. Strain-specific antisera were prepared against each strain. Field experiments were conducted in Antigua using Rhizobium strains USDA 3384, USDA 3473, and USDA 3474 as a peat-base inoculant and pigeon pea as the test crop. Nodules from the respective treatments were removed and prepared for ELISA studies. There was cross reactivity between the antisera, but it was greatly reduced or eliminated by repeat adsorption with the cells of the cross-reacting strains. Nodule occupancy by plants treated with Rhizobium 3384, 3473, and 3384 was 70%, 90%, and 100%, respectively. Nodules from 3384 and 3474 treated plants contained cells with no antigenic homology to the three antisera. We concluded that these nodules were developed from indigenous Rhizobium strains found in Antiguan soils.
EFFECT OF DURATION OF STORING VINE CUTTINGS ON YIELD OF SWEETPOTATOES GROWN IN NFT
Authors: Seminara Jennifer L. , Mortley Desmond G. , Loretan Philip A. , Smith Beverly
Published: February 2019

Two trials were conducted to determine the effect of duration of storing vine cuttings on yield of sweetpotatoes grown under greenhouse conditions in nutrient film technique. TI-155 sweetpotato [Ipomoea batatas (L). Lam.] vine cuttings with leaves removed were stored at room temperature in an open basket for 0, 3, 5, and 7 days before planting in a complete randomized design with two replications. A modified half Hoagland's nutrient solution was used. Nutrient solution pH was maintained between 5.5 and 6.0 and changed every 2 weeks. Salinity, electrical conductivity, and solution temperature were monitored at regular intervals. Results show a trend toward increased percent dry matter as storage duration increased. Storing vine cuttings for 5 days produced the highest yield of storage root fresh and dry weights. Foliage fresh and dry weights were not influenced by preplanting treatments.
EFFECTS OF WINTER COVER CROPS AND N APPLICATIONS ON VEGETABLE CROP PRODUCTION SYSTEMS
Authors: Batal K.M. , Hall M.R. , Granberry D.M. , Garrett J.T. , Decoteau D.R. , Dufault R.T. , Hoyt G.D. , Gilsanz T.C. , Davis J.M. , Sanders D.C.
Published: February 2019

A vegetable production system using winter cover crops and N rates was evaluated for several years in Georgia, South Carolina, and North Carolina. Snap bean, cucumber, tomato, potato, and sweetpotato crops were tested at different locations. Cover crop plots produced higher yields and better quality in all locations as seasons progressed over 4 years. Soil N levels in fallow, wheat, and clover plots were similar at initiation, but N gradually increased in clover plots in successive years. Yield and quality of root crops improved with Crimson clover without N applications compared to fallow plots with 60 kg N/ha. Effects on yield and tuber size are discussed. Nitrate and NH4-N in the soil profile from 15- to 150-cm depth were monitored at all locations. Nitrogen availability, depletion, and leaching below the root zone were determined. At low N rate, clover plots had slightly higher NO3 in the soil profile; however, at high N rate, N supply by clover was not as critical, and N leaching was detected at much lower depths than at low N rates.
MIDGES MAY INJURE DRUPELETS AND REDUCE FRUIT-SET IN BLACKBERRIES
Authors: Stiles Herbert D. , Semtner Paul J.
Published: February 2019

Blackberry drupelet development is influenced by a number of agents (Ellis et al., 1991; Moore and Skirvin, 1990). We have observed poor drupelet-setting and `nubbins' that were not attributable to common pests, such as tarnished plant bug or diseases. In seeking causes for such problems during 1986, we discovered tiny (diptera) larvae in unopened flower buds and newly opened blossoms of wild-growing and domestic blackberries. Pistils and stamens of infested buds and blossoms showed signs of necrosis; injuries seemed worse in buds that contained more larvae. We confirmed relationships among bloom-time symptoms, drupelet setting, and fruit weight by tagging symptomatic and asymptomatic postanthesis blossoms on 22 May 1989. One week before the normal harvest season, symptomatic berries averaged 38 mg and asymptomatic berries averaged 208 mg. Twelve symptomatic blossoms (27%) produced no drupelets, 19 (43%) produced one to 10 drupelets, and no symptomatic blossom yielded a normal berry. We devised or adapted larval collection and rearing apparatuses and procedures to obtain adult midges that were needed for taxonomic speciation of this new blackberry pest. During 1994, SEL identified resultant specimens as Contarinia agrimoniae Felt. This genus previously had not been recorded from Rubus buds, and little is known of C. agrimoniae habits, life cycle, etc. Additional studies are needed to identify procedures for management of C. agrimoniae.
PATTERNS OF ROOTSTOCK USAGE IN THE PECAN INDUSTRY
Authors: Grauke L.J. , Thompson Tommy E.
Published: February 2019

The commercial pecan [Carya illinoinensis (Wangenh.) K. Koch] nursery industry relies on open-pollinated seed for rootstock production. Current choice of seedstocks by commercial pecan nurserymen was surveyed by telephone. Nurseries were called if they appeared in the directory used for the 1994 release of `Navaho'. Factors influencing the choice of seedstock include seed availability, nut fill, nut size, nut shape, seedling vigor, stand uniformity, and root characteristics. Local availability is important in the choice of seedstock. Those who harvest from their own trees usually credit the seedstock with other valuable characteristics, such as improved germination or vigor. Those who purchase seed usually target a preferred seedstocks for particular reasons but plant available seed in its absence. Well-filled nuts are recognized as being important for good germination. Small nuts are often preferred, especially when seed is purchased because more nuts per pound increases potential production. Round nuts are generally preferred over long nuts due to improved performance in some mechanical planters. Distinct regional preferences are apparent in the choice of seedstocks. Regionally preferred seedstock selections are generally validated by a survey of the research literature. Patterns of selection are consistent with climatic and geographic constraints. Tree procurement patterns have changed: many small nurseries have gone out of business, many large nurseries transport trees far from the nursery for sales, and quarantine restrictions have altered procurement patterns in Arizona. Recommendations are made to nurserymen, pecan growers, and researchers concerning continued progress toward improving regionally adapted pecan rootstocks through seedstock selection.
PECAN KERNEL COLOR: STANDARDS USING MUNSELL COLOR CHIPS
Authors: Thompson Tommy E. , Grauke L.J. , Young E.F.
Published: February 2019

The Munsell Color System was used to study pecan [Carya illinoinensis (Wangenh.) K. Koch] kernel colors and color changes for 21 clones, 11 locations, and five storage methods for nuts collected over 4 years. Hue readings ranged from 10.0 (10 red) to 22.5 (2.5 yellow). Value readings ranged from 2.0 to 8.0, and chroma readings ranged from 1.0 to 8.0. A total of 91 classes (individual combinations of hue, value, and chroma) were needed to describe all kernel colors. Overall, one class 115.0/5/4 (hue/value/chroma)] accounted for 3979 of the 32,078 readings taken, and the 15 most common classes accounted for 80.7% of all the readings. This system of color determination was well-suited for pecan color determinations and continues to be used routinely as a part of our breeding and genetics program to define this important quality trait in pecan.
METHODS OF CONTROLLING OVERCROWDING FOR PECANS
Authors: Worley Ray E. , Mullinix Ben
Published: February 2019

Treatments of control, selective limb pruning (SLP), tree thinning, SLP + 12.24 kg paclobutrazol/ha, and SLP + 3.36 kg paclobutrazol/ha were applied to `Desirable', `Western Schley', and `Wichita' pecans for >7 years. Thinning increased yield per tree significantly for `Desirable' but not for the other cultivars. Thinning did not increase yield per hectare during the study. Paclobutrazol application reduced terminal shoot growth but did not benefit yield or kernel quality. There was no significant benefit from SLP with or without paclobutrazol.
THE EFFECTS OF PHOTOPERIOD AND TEMPERATURE ON FORCING OF OXALIS REGNELLII AND O. TRIANGULARIS
Authors: De Hertogh A.A. , Gallitano L. , Kim K.
Published: February 2019

In recent years, several physiological disorders of unknown origin have been observed on Oxalis regnellii and O. triangularis, two widely forced species. Therefore, an experiment was carried out in the NCSU Phytotron. The forcing temperatures were 18/14C, 22/18C, and 26/22C (day/night), and these temperatures were combined with 9-h and long day (3-h night break) photoperiods. In addition, two planting media (Metro 360 and Sunshine no. 4) were used. Control plants were grown under greenhouse conditions. With O. regnellii, leaf chlorosis and wrinkling were prevalent in the greenhouse. In the phytotron, the highest quality plants with the least amount of leaf disorders were produced under LD at 26/22C. No differences were obtained with the planting media. With O. triangularis, the highest quality plants with the least leaf disorders (bronzing and wrinkling) were grown in the phytotron at 26/22C. In addition, LD significantly enhanced flowering. Leaf disorders were prevalent in the greenhouse and enhanced with Sunshine no. 4.
EVALUATION OF WATER HYACINTH [EICHORNIA CRASSIPES (MART.) SOLMS-LAMB] FOR THE REMOVAL OF NITROGEN IN NURSERY RUNOFF
Authors: Harp Derald A. , McWilliams Ed
Published: February 2019

The ability of water hyacinth to remove N from nursery runoff was evaluated in two separate experiments. In Expt. 1, individual plants were placed in 10-liter ceramic containers with nutrient solutions with varying levels of N (0, 1.5, 3, 6, 12, and 24 mm). In Expt. 2, plants were placed in pools used to mimic runoff ponds. Pools were filled with 80 liters of reverse osmosis water, 2 cm of a native sandy loam, and either 48.03 or 24.015 g of 20–10–20 Peters water-soluble fertilizer. Plants in ceramic containers had no significant difference in weight gain across treatments (P < 0.05). However, the 24 mm treatment did have significantly more N remaining in the solution than other treatment levels. Plants in the pool experiments exposed to 3.0 mm N had significant increases in number of new plants produced and total biomass production over those exposed to 1.5 mm N. No differences existed in the amount of time needed to remove N because N was undetectable after 18 to 23 days at 3 and 1.5 mm.
DEVELOPMENT OF IRRIGATION AND FERTILIZATION BEST MANAGEMENT PRACTICES FOR CONTAINER NURSERIES.
Authors: Yeager Tom , Fare Donna , Gilliam Charles , Niemiera Alex
Published: February 2019

More regulations have an impact on nursery industry today than 10 to 20 years ago, and additional regulations are likely in the future. In view of this, the southeastern nursery industry is taking proactive action by developing a handbook of irrigation and fertilization best management practices (BMP) for container nurseries. Using BMP would be voluntary but could “head off” additional regulations. Additionally, BMP would serve as guidelines for growers 1) attempting to be more environmentally friendly, 2) wanting to promote the fact they are environmentally friendly, and 3) dealing with a complaint from regulatory agencies. Our objective was to develop a BMP handbook that nursery managers could use to find answers quickly to management questions regarding irrigation and fertilization. The handbook was written by university horticulturists, but input and reviews were obtained from industry personnel, additional university personnel, and others associated with the nursery industry. The handbook will be distributed in late summer by the Southern Nurserymen's Association, Marietta, Ga.
CHEMICAL MANIPULATION OF GRAPE DORMANCY UNDER SIMULATED TROPICAL CONDITIONS
Authors: Matta Frank B. , Njue Obadiah M.
Published: February 2019

Defoliating chemicals (ammonium thiosulfate, ethrel, and thidiazuron) were evaluated on 8-month-old `Canadice' and `Concord' grapes. The effectiveness of chemical defoliators was determined 20 days after application. Vines were pruned after defoliation and dormancy breaking chemicals (thiourea, cyanamide, and gibberellic acid (GA3) were applied 4 days later. All treatments were applied as sprays. All chemicals were effective in defoliating the vines of both cultivars. Generally, the higher concentrations (ammonium thiosulfate, ethrel, and thidiazuron at 15.15, 3.0, and 0.35 g·liter–1, respectively) were more effective. All chemicals reduced days to maximum budbreak of both cultivars. The higher concentrations (thiourea, cyanamide, and GA3 at 30.3, 15.15, and 0.75 g·liter–1, respectively) resulted in greater reductions in days to maximum budbreak. `Concord' was later in reaching maximum budbreak. Total percent budbreak of both cultivars was increased by all chemicals at the higher concentrations. Cyanamide resulted in greater total percent budbreak in both cultivars.
PRELIMINARY STUDY ON THE EFFECT OF ROOT ZONE TEMPERATURES ON VEGETATIVE GROWTH AND LEAF MINERAL NUTRIENTS OF `GULF COAST' BLUEBERRY PLANTS
Authors: Makus D.J. , Spiers J.M.
Published: February 2019

The effect of root zone temperature (temp.) on 18-month-old plants of `Gulf Coast' blueberries (predominantly Vaccinium corymbosum L.) grown in temperature-controlled water tanks during Summer 1993 were determined for plant growth and leaf nutrient status. Soil medium (1 sand: 1 peat, v/v) was maintained at or above –20 k Pa. Six singleplant replicates were placed in either a 24 or 31C tank. After 60 days, plants grown at 24C had more leaves, greater total leaf area, and higher leaf and stem fresh weight. Leaf moisture (P < 0.09) and stem dry wt (P < 0.07) were greater at the lower root temp. Root: shoot ratio and total root dry weight were not affected by root temp. Leaf S and Cu levels were higher and NO3 levels lower in plants grown at the 24C root temp. compared to those grown in the 31C root temp. Nitrogen, K, Na, Ca, Mg, P, Fe, Mn, and Zn (order of decreasing concentration) were not affected by root temp. The total N: NO3-N ratio was higher at the lower root zone temp.
PAWPAW (ASIMINA TRILOBA) SEEDLING GROWTH AND DEVELOPMENT: INFLUENCE OF INCIDENT LIGHT INTENSITY AND FERTILIZATION REGIME
Authors: Jones Lakesha , Layne Desmond R. , Kwantes Michael G.
Published: February 2019

The role of incident light intensity (light) and fertilization regime (Fert) on early growth and development of pawpaw seedlings in the greenhouse was investigated. Three-hundred and fifty stratified seeds were sown in 45 cubic inches. Rootrainer cells in Promix BX potting medium. A two-factor factorial design was used. Light was either ambient (Amb) or 80% shaded (Shade) Fert was 500 ppm of Peter's 20N–20P–20K plus soluble trace elements (+ Fert) or water (–Fert) applied twice weekly to runoff. Thirty uniform seedlings were selected at the two- to three-leaf stage for each of the four treatments. Treatment imposition was for 5 weeks until the 10- to 11-leaf stage (when seedlings would be transplanted). Plant height and leaf number was recorded three times weekly. After 5 weeks, 15 uniform plants per treatment were destructively harvested and leaf chlorophyll (chl) analysis was performed. Amb/+ Fert plants were 25% taller and had two more unfolded leaves, on average, than the other treatments.–Fert plants (Amb or Shade) had set terminal buds. The effect of Fert on chl was much greater under Amb than Shade conditions. For–Fert plants, total chl was reduced by 52% under Amb but only 30% under Shade compared to +Fert plants. Total biomass for Amb/–Fert seedling was double that in either Shade treatment and 40% greater than for Amb/–Fert seedlings.
THE OCCURRENCE OF PLUM LEAF SCALD ON PLUM CULTIVARS IN ALABAMA
Authors: Tangsukkasemsan B. , Norton J.D. , Boyhan G.E.
Published: February 2019

Naturally infected plum leaves were collected during Aug. and Sept. 1994 to evaluated for the presence of Xylella fastidiosa, the causal agent of plum leaf scald (PLS). Leaves were from trees at least 4 years old in variety trials at four locations in Alabama. ELISA tests for X. fastidiosa were used to determine the presence of the organism in infected trees. The symptoms also were evaluated with a rating index for PLS. Some plum cultivars (i.e., `AU-Producer', `Morris', `Explorer', and `AU-Cherry') showed high tolerance to PLS. Both ELISA tests and visual observation indicated that an Auburn Univ. seedling (CD-l 22) was free from this disease. PLS infection was lower in North Alabama compared to Central Alabama.
CONTROL OF BLACK SPOT ON ROSES WITH CYPROCONAZOLE USED AS A DRENCH
Authors: Roberson William E. , Pemberton H. Brent , Philley George L.
Published: February 2019

To determine the efficacy of cyproconazole for control of black spot [Marssonina rosae (Lib.) Lind] when applied as a drench, treatments of 0, 32.5, 65, 97.5 and 130 g a.i./ha were initiated 9 May 1994 on individual Rosa `Peace' plants in a randomized complete-block design. Treatments were applied once per month until 18 Oct. 1994. Data were taken in July, Sept., and Nov. 1994 when separate disease and defoliation ratings were assigned. By July, the controls were heavily infected; the higher treatment rates resulted in significant control. By September, the disease and defoliation ratings exhibited a linear response with cyproconazole rate, with the highest treatment rate giving the best control. The relationship between disease and defoliation ratings and treatment rate remained the same in November, although there was increased disease incidence overall. No phytotoxicity was observed. These results indicate that soil applied treatments of cyproconazole can control black spot effectively on roses.
CONSUMER PREFERENCES FOR GERANIUM FLOWER COLOR AND LEAF VARIEGATION
Authors: Hudson J.J. , Nelson R.G. , Behe B.K.
Published: February 2019

Some consumer preference studies show that red is the most popular flower color. Most data analyses were univariate. Conjoint analysis allows simultaneous determination of attribute preferences without all alternatives being shown. Our purpose was to determine consumer preferences for geranium flower color, leaf variegation, and price simultaneously using conjoint analysis. Two-hundred and four consumers shopping at two Montgomery, Ala., garden centers in Apr. 1993 rated 25 composite geranium photographs. A lavender geranium, `Danielle', with green and white leaf variegation priced at $1.39 was most preferred. Flower color was most important in the purchase decision, followed by price. Leaf variegation was a minor consideration in the purchase decision.
SUBJECTIVE AND OBJECTIVE EVALUATION OF COLOR IN BELL PEPPER
Authors: Simonne E.H. , Eason J.T. , Pitts J.A. , Owen J.T.
Published: February 2019

Bell pepper (Capsicum annuum L.) fruit are typically green in color at the immature stage, 1/3 and 2/3 colored during ripening, and red at maturity. However, this sequence does not apply to new varieties with immature colors of white or purple, intermediate colors of brown or black, and mature colors of yellow or orange. The study of physiological changes during ripening in such cultivars requires the description of color changes. Therefore, color changes of new bell pepper varieties were evaluated by subjective description and objective measurement of L, a, and b. Color changes were described with a five-color stage scale. L, a, and b were affected significantly by variety (P < 0.01), and a and b were affected significantly by color stage (P = 0.95, 0.01, and 0.01 for L, a, and b, respectively). Location and cultivar*location had no significant effect. For each cultivar, differences in a and b values defined color stages that were clearly identifiable. When plotted, color measurements (a and b) were in good agreement with the verbal descriptions. Therefore, measurements of L, a, and b are not systematically necessary when referring to bell pepper colors.
GENETIC RELATIONSHIPS AMONG U.S. SWEETPOTATO CULTIVARS ANALYZED BY DNA AMPLIFICATION FINGER-PRINTING
Authors: Prakash C.S. , He G. , Jarret R.
Published: February 2019

The PCR-based DNA amplification fingerprinting (DAF) approach was used to investigate the evolutionary relationships among 30 U.S. sweetpotato cultivars. Phenogram and pairwise similarity matrix based on Jaccard's coefficients showed relationships among U.S. cultivars and their progenitors to be consistent with the pedigree history. The genetic variability of U.S. cultivars was relatively low (compared to a sample of global collection). Many older U.S. cultivars formed a cluster in the principal coordinate analysis, suggesting their narrow genetic base, but new cultivars, such as `Regal' and `Excel', showed greater divergence. Somatic mutants showed close genetic similarity with their wild types and yet distinct in fingerprint profiles (e.g., `Resisto' and `Copper Resisto'; `Redmar' and `Goldmar'). All cultivars showed unique DAF profiles, and thus, the DAF approach enabled cultivar identification. `Centennial' showed high similarity to major U.S. cultivars such as `Jewel' and `Rojo Blanco'. `Regal' and its open-pollinated offspring `Excel' showed high similarity with each other. `Jewel', the most leading sweetpotato cultivar in the United States, clustered closely to its parent `Nugget' (83%). Carver, a selection from a cross `Centennial' × `Jewel', showed 75% similarity with `Jewel' and 63% similarity to `Centennial'. `Scarlet', a mutant of `Jewel', appeared in the same cluster as `Jewel' but showed only 68% similarity. Our results show that DAF may be an useful approach in elucidating evolutionary relationships among sweetpotato cultivars.
RAPD MARKERS ASSOCIATED WITH SINGLE GENE TRAITS IN IPOMOEA TRIFIDA
Authors: Wolters Petra , Collins Wanda W.
Published: February 2019

Ipomoea trifida (2X = 30) is purported to be the wild Ipomoea species most closely related to the commercially grown Ipomoea batatas (sweetpotato, 6X = 90). The two species can be crossed with much difficulty, but seed occur rarely. Ipomoea trifida has been shown to possess some agronomically desirable traits that are missing in sweetpotato (e.g., sweetpotato-weevil resistance). Attempts to locate morphological markers in the diploid trifida that would serve as indicators of successful crosses with sweetpotato resulted in the identification of two traits controlled by single genes: nectary color and male sterility. Both traits require flowering to identify, and flowering is often difficult to induce in Ipomoea species. An analysis of I. trifida accessions using RAPD molecular markers was undertaken. Using a segregant population resulting from crossing a green nectary, fertile plant with a yellow nectary, male, sterile plant, RAPD analysis resulted in clear markers for both the nectary color trait and the male sterility trait. These traits now can be identified in the absence of flowering plants.
BEDDING COVER ALTERNATIVES FOR SWEETPOTATO PRODUCTION
Authors: Schultheis Jonathan R. , Monks David W.
Published: February 2019

Bedded sweetpotatoes are often covered with a rowcover to enhance sprouting. Our study was conducted to evaluate several rowcovers for earliness, plant yield, and plant quality (weight). In 1993 and 1994, variety (`Beauregard' and `Jewel') and rowcovers (clear plastic; black plastic; photodegradable plastic; infrared transmissible plastic; Reemay polyester cover; and black plastic, which was then covered with a black plastic tunnel) were evaluated for their effects on plant production. Holes ≈1 cm in diameter were punched in the plastic ≈2 weeks after planting to prevent exposing the seed roots to excessively high temperatures. Rowcovers were removed when plants began emerging from the soil, except for Reemay and the black plastic tunnels, which remained in place over the bedded plants until first plant harvest. Black plastic tunnels were placed back over the treatment bed each time plants were harvested. When 50% of the plants were 25 cm tall, all plants from the plot were cut 1 to 2 cm above the soil line. Plots were arranged in a randomized complete-block design and replicated five times. `Jewel' produced plants earlier than `Beauregard'. Covering beds with black plastic mulch and tunnels resulted in the first plant cutting being up to 42 days earlier than the other treatments, with no rowcover treatments producing plants the latest. The second earliest cutting was obtained when beds were covered with Reemay rowcover. Plant fresh weight was greater with the no cover treatments; black plastic tunnel treatments produced the lowest weight plants. Using black plastic tunnels consistently produced more plants than the other treatments. In the future, using rowcovers to enhance slower sprouting varieties should be examined.
OIL REDUCTION OF SHELLED PECANS USING SUPERCRITICAL CARBON DIOXIDE
Authors: Maness Niels O. , Smith Michael W. , Zhang C. , Brusewitz Gerald H.
Published: February 2019

Techniques to reduce the oil content of shelled pecans using supercritical CO2 have been developed, and the effect of partial oil extraction on kernel quality is being investigated. Extraction conditions induce little kernel damage and allow for up to 30% oil reduction. Extraction temperature, at 40 or 80C, influenced kernel color. Regardless of temperature, extracted nut meat was lighter in color. Testa color increased in redness for kernels extracted at 80C compared to kernels extracted at 40C. Extracted oil was amber. Fatty acid composition of oil obtained with supercritical CO2 was essentially the same as oil obtained by organic solvent extraction and by cold press. Investigations to determine the effect of oil reduction on pecan shelf life are described. This research was supported by U.S. Department of Agriculture grant 92-34150-7190, Oklahoma Center for Advancement of Science and Technology grant AR4-044, and the Oklahoma Agricultural Experiment Station.
Regulation of Bell Pepper Seedling Growth with End-of-day Supplemental Fluorescent Light
Authors: Graham Heather A. Hatt , Decoteau Dennis R.
Published: February 2019

The influence of end-of-day (EOD), supplemental, cool-white fluorescent light on pepper (Capsicum annuum L. cv. Keystone Resistant Giant No. 3) seedling growth and fruit production after transplanting to the field was investigated. Seedlings were exposed to this light source, which is high in the red wavebands, from one (1988) or two bulbs (1989) for 1 hour before the end of the natural photoperiod. Each year control plants were exposed to ambient light and received no supplemental fluorescent light. Before transplanting to the field, seedlings exposed to two bulbs were shorter and had smaller leaves than plants in the control treatment. Supplemental fluorescent light treatment, regardless of number of bulbs, reduced plant height, leaf area, fruit weight, and fruit count at the first harvest. Total fruit production was not affected by supplemental light, suggesting no residual effect of the light treatment during transplant production on total subsequent fruit production.
Screening Tomato Accessions for Resistance to Xanthomonas campestris pv. vesicatoria, Race T3
Authors: Scott J.W. , Jones J.B. , Somodi G.C. , Stall R.E.
Published: February 2019

Tomato (Lycopersicon esculentum Mill.) accessions were tested for hypersensitivity and rated for resistance following field inoculation with tomato race 3 (T3) of the bacterial spot pathogen Xanthomonas campestris pv. vesicatoria (Doidge) Dye (Xcv) in 1992 and 1993. Hawaii 7981, PI 126932, PI 128216, and selections of the latter two expressed hypersensitivity. Hawaii 7981, only tested in the field in 1993, was nearly symptomless and developed significantly less disease than any other accession. PI 128216 had a level of disease similar to susceptible `Solar Set' when tested in 1993. However, a selection from it (PI 126218-S) was significantly more resistant than `Solar Set' in both years. Although PI 126932 had a level of disease similar to `Solar Set' in both years, a selection from it (PI 126932-1-2) was significantly more resistant than `Solar Set' in 1993. Other accessions without hypersensitive responses but more resistant than `Solar Set' for two seasons were PI 114490, PI 126428, PI 340905-S, and PI 155372. Hawaii 7975 was significantly more resistant than `Solar Set' in the one season it was tested.
Screening Highbush Blueberry Cultivars for Resistance to Phomopsis Canker
Authors: Baker Jean Beard , Hancock J.F. , Ramsdell D.C.
Published: February 2019

One-year-old rooted microshoots and 2-year-old rooted hardwood blueberry cuttings (Vaccinium corymbosum L.) were inoculated with Phomopsis vaccinii Shear using stem flap, stem freeze, needle pierce, and leaf tear wounding techniques. The needle pierce was the simplest method that produced high infection rates. Nine northern-adapted cultivars were placed in a factorial experiment to measure their infection resistance. Microshoots and hardwood cuttings of `Elliott' and `Bluetta' survived the longest and had the lowest mortality rate. Phomopsis vaccinii was reisolated successfully from inoculated shoots of all cultivars.
Identification of Intracultivar Genetic Heterogeneity in Cranberry Using Silver-stained RAPDs
Authors: Novy Richard G. , Vorsa Nicholi
Published: February 2019

Cranberry (Vaccinium macrocarpon Ait.) has few qualitative, morphological characteristics that can be used to reliably distinguish among cultivars. Fifty-two silver-stained random amplified polymorphic DNAs (ssRAPDs) were used to assess genetic heterogeneity and relatedness within accessions of four major cranberry cultivars (`Early Black', `Howes', `McFarlin', and `Searles'). Rather than being represented by one genotype, as might be expected in an asexually propagated crop, each cultivar was represented by multiple genotypes, which in many cases did not appear to be closely related to one another. The intracultivar heterogeneity was often so extreme that clonal representatives of a cultivar would group with representatives of other cultivars following cluster analysis. Of the total ssRAPD variation, 9.7% could be attributed to variation among the four cultivar groups and 90.3% to variation within the cultivars. `Howes' was the only cultivar in which a consensus DNA fingerprint among regional representatives could be identified.
Genetic Studies in Pea and Apple: The Yin and Yang of Mapping in Plants
Authors: Weeden N.F.
Published: February 2019

Linkage maps consisting primarily of molecular markers have been constructed in pea and apple. Different approaches have been taken to generate these maps. For pea, F2 and recombinant inbred populations have been used to study segregating loci, and a critical factor has been the selection of sufficiently divergent inbred parents for the crosses. In contrast, a double pseudotestcross format has been used in apple, and virutally every variety possesses sufficient heterozygosity to permit the development of a map by examination of the F1. Markers have been identified for many genes in each crop.
Junior Faculty: Their Needs and Professional Development
Authors: Fink Dee
Published: February 2019

This presentation will summarize research on the characteristics and needs of junior faculty in North America. Following this will be a description of practices that various institutions, department chairs, and new faculty themselves are using to assist new faculty. The general perspective is that this is a critical time in the careers of faculty members, one that will have a major influence on their research and teaching activities for a long period of time.
Mid-career and Senior Faculty: Maintaining Vitality and Productivity
Authors: Wheeler Daniel W.
Published: February 2019

Over the past 25 years, faculty and their work have been studied on an intensive level. In 1977, Sarason defined a “one life—one career” model, in which faculty are “called” to a profession. Numerous studies, beginning with Hodgekinson (1974) and Baldwin and Blackburn (1981), indicate that faculty as adult learners continue to explore new interests and redefine careers, particularly as age and experience increase. Although the institutional context is a mediating factor, a number of researchers, including Baldwin (1985), Creswell, et. al. (1990), Schuster and Wheeler (1990), Simpson (1990), and Sorcinelli and Austin (1992) have identified a range of faculty needs and strategies which can aid in meeting these needs. Department chairs and faculty colleagues are identified as crucial in encouraging changes to maintain faculty vitality, and to encourage preventative action rather than remediation. Such investments in human capital have both short-term and long-term payoffs [Simpson (1990) and Schuster and Wheeler (1990)].
Development of Multimedia Software for Plant Materials Courses and the Landscape Industry—A Developer's Perspective
Authors: Kling Gary , Lindsey Christopher , Zampardo Mark
Published: February 2019

The authors present a case study of the progress and development of UIPLANTS from its inception to marketing. Topics such as determining the objectives of the software program, choosing equipment, authoring software, hardware, personnel, and funding will be addressed. The authors will lead the audience through the path of development and show how the product being produced evolves as each of the above factors change in time. Included in the presentation will be issues relating to copyrights, patents, publishers, and royalties. The effects of continuous evaluation and testing of software development will be demonstrated. Also discussed will be changes in software development as influenced by each of these factors. The presentation will include future development of UIPLANTS as it is being modified to meet industry needs.
Canadian Peat Harvesting and Its Effects on the Environment
Authors: Hood G.O.
Published: February 2019

Canadian sphagnum peat moss has long been the preferred base for growing media of horticulturists in North America and Europe. Growers, horticultural scientists, and soil media producers have been using peat moss for several decades with excellent results. In the past 5 years, there has been some concern raised, especially in the U.K., that harvesting peat is harmful to the environment. The situation in Canada is far different from that in Europe. The Canadian peat industry is a world leader in restoration research because of its efforts to find the best ways to return harvested bogs to functioning wetlands. The first stage of research just completed by Laval Univ. shows that peat bogs can be effectively, economically, and easily restored. Additional research findings will be described in this paper. But, the conclusion is clear: Peat moss is a safe, environmentally friendly growing medium. This paper also will describe the state of resource in Canada as outlined by an independent environmental group, the steps taken by the Canadian Sphagnum Peat Moss Assn. to ensure that resource development is sustainable, as well as the process of how peat is harvest and how bogs are restored to functioning wetlands.
Effects of Transplanting Depth of Pepper on Flowering and Fruit Characteristics
Authors: Kelley William Terry , Granberry Darbie M.
Published: February 2019

Bell pepper (Capsicum annuum) is traditionally transplanted either to the top of the root ball or to the cotyledons of the transplant. Recent evidence has shown that increased and earlier yields may be obtained by deeper transplanting of pepper. Thus, a study was undertaken to investigate the effects of pepper transplanting depth on flowering and the fruit characteristics of harvest fruit. Pepper was transplanted to the top of the rootball, the cotyledons, and the first true leaf at two locations in 1994. Both `Camelot' Hybrid and `Jupiter' (open-pollinated) cultivars were planted into bareground on Mar. 24 at Tifton, Ga. Only `Camelot' was transplanted into a plastic mulch with drip irrigation on Mar. 28 at Cool Springs. Plots consisted of a single row of seven plants with the internal five plants used for data collection. Treatments were replicated three times. Normal cultural and pest control practices were used at both locations. Data on flowering were collected 5 weeks after transplanting. Data on fruit characteristics were collected at harvest. Number of bloom clusters per plant, number of blooms per cluster, number of open blooms, and number of set blooms were significantly greater in the deeper-planted pepper at Cool Springs. The same was true for bloom clusters and blooms per cluster at Tifton. Number of blooms open and set were greater in deeper-planted `Camelot' at Tifton as well. There were virtually no differences among characteristics of harvest fruit. Earlier bloom set appears to occur in deeper-planted pepper on both bareground and mulched beds.