bluuebunny/crossref_metadata_2025 huggingface dataset:
LOCALLY OBTAINED WATERMELON TRANSPLANTS OUTPERFORM FLORIDA TRANSPLANTS IN ARKANSAS FIELD TRIALS
Authors: Teague Tina Gray
Published: February 2019

Four week old watermelon (cv. Royal Sweet) transplants were obtained from long distance (FL) and local (AR) commercial transplant growers and set in plots in a commercial watermelon field near Leachville AR. Transplants (plugs) from AR (Burton's Inc., Tupelo, AR) were grown in inverted pyramid, Todd Flats (model 100A; 5/8″ length X 1/2″ width X 3″ height) (Speedling Inc., Sun City, FL). FL transplants (LaBelle Plant World, LaBelle, FL) were grown in 1.5″ square cells, 2″ deep. All transplants were delivered 15 April and set on 16 April. Transit time for local transplants was < 2 hrs, and plants were delivered in original flats. FL transplants were shipped on 14 April and were in transit ca. 28 hrs. They had been pulled from trays and were shipped in cardboard boxes. Plot size was 6 beds, 53.3m long with treatments arranged in a RCB with 4 replications. Bed spacing was 2.9m with between plant spacing of 1.5m. Data were subjected to ANOVA with mean separation by LSD.

Plots were harvested 3, 8, 15 and 22 July. Total number of fruit produced from plots planted with AR transplants was greater than FL treatment plots in the first 3 of 4 harvests; significantly higher total cumulative yield was observed with AR compared to FL transplants (45,115 and 35,172 kg ha-1, respectively). Increases in-yield and earliness resulted in an increase in gross profit of $1225 ha-1 for local transplants (based on national price data from that time period). No differences in average weights of fruit were observed for any harvests. Results indicate that Mid-South watermelon producers could benefit from utilizing locally grown transplants if plants are of comparable quality to those available from distant suppliers.
ALKALINE WATER ACIDIFICATION INFLUENCES SODIUM UPTAKE BY AZALEA
Authors: Bush E. W. , Robbins M. L. , Wall D. A.
Published: February 2019

Sodium bicarbonate type irrigation water is detrimental to the growth of Azalea indica `Formosa'. Alkaline irrigation water reduced both top and root growth of `Formosa' azalea. Leaf tissue sodium was significantly greater in azalea plant tissue irrigated with alkaline water. Concentrated sulfuric acid was used to acidify the alkaline water source. Acidification significantly reduced the uptake of sodium into the leaf tissue by 45%. Leaf tissue Ca and Mg levels were significantly greater from plants irrigated wtih deionized water. Azalea plants irrigated with acidified water produced significantly better quality plants. Leaf and root tissue samples were taken after 8 months.
CONTROLLING HEIGHT AND FLOWERING IN HYPOESTES PHYLLOSTACHYA
Authors: Wang Chi , Grueber Kevin L.
Published: February 2019

Control of plant height and flowering are two major problems associated with the production of Hypoestes phyllostachya Bak. (polka-dot plant). In seed-propagated cultivars, sprays of ancymidol (A-Rest), chlormequat (Cycocel), paclobutrazol (Bonzi), and uniconazole (Sumagic) were effective in inhibiting shoot growth and internode elongation at 100, 1000, 33, and 10 mg·l-1, respectively. Daminozide (B-Nine), even at 6000 mg·l-1, was ineffective compared to untreated controls. Ethephon (Florel) was effective in retarding plant growth at 500 mg·l-1, but at 1500 mg·l-1 resulted in leaf distortion and horizontal shoot growth.

H. phyllostachya was determined to be a quantitative (facultative) short day plant. Seed-propagated plants with 16 or more nodes flowered regardless of photoperiod, but flowering was more rapid under short days (SD) than under long days (LD). Application of ethephon significantly inhibited shoot elongatioo and number of flower buds formed and also increased the incidence of flower bud abortion. In seed-propagated plants, 500 mg·l-1 ethephon did not adversely affect flowering when applied at any time during the first seven weeks after the start of SD. At 1500 or 2500 mg·l-1, ethephon applied at any time during the first five weeks after the start of SD maximized the number of vegetative buds and minimized the number of viable flower buds. When applied more than six weeks after SD began, ethephon did not promote the formation of vegetative axillary buds but did promote flower bud abortion.
Three-dimensional Characterization of Bearing Pecan Tree
Authors: Lozano-Gonzalez Ricardo , Storey J. Benton , Harris Marvin K.
Published: February 2019

Three-dimensional leaf and fruit distribution was studied in a 26-year-old `Success' pecan tree [Carya illinoinensis (Wangenh.) K. Koch]. The tree was typical of the trees in this orchard and typical of thousands of hectares of mature pecan trees growing in a crowded condition. There are fewer leaves and fruit in the lower and central canopy than in the rest of the tree. To obtain an adequate sample, measurements should be taken from branches arising at a height ≥4.75 m and from 1.9 m from the center of the tree trunk to the edge of the canopy around the trees. Fruit could be sampled from branches arising at ≥3.76 m from the ground and from 3.37 m from the center of the tree trunk to the edge of the canopy around the tree.
Prediction of Flowering Time in Olive for the Cordoba Olive Collection
Authors: Alcalá A.R. , Barranco D.
Published: February 2019

The date of full bloom for olive (Olea europaea L.) tree varieties planted in the World Collection in Córdoba, Spain, has been determined from 10 years of data. The full bloom dates were analyzed using three methods to develop a model predicting flowering time. The method of heat units accumulated before flowering was the most accurate. The heat accumulation periods were determined from phenological and temperature data. Prediction methods were evaluated for the earliest-flowering variety, a model variety representing the mean values for the collection, and the latest-flowering variety. The most appropriate threshold temperature for heat accumulation has been confirmed to be 12.5C; it can be used to predict the flowering time in olive.
Estimation of Outcrossing in Basil
Authors: Nation Renee G. , Janick Jules , Simon James E.
Published: February 2019

The rate of outcrossing in basil [eight accessions of Ocimum basilicum L. and one accession purported to be O. kilimandscharicum Guerke (`Juicy Fruit')] was estimated using a purple seedling marker in `Dark Opal' (O. basilicum). There were two patterns of outcrossing: `Picollo' and four sources of `Cinnamon' basil had outcrossing rates between 19.9% and 32.8%, while `Lemon', PI 368699, PI 174284, and a Purdue selection named `Juicy Fruit' had outcrossing rates between 1.6% and 3.4%.
QUALITY ENHANCEMENT OF APPLES USING SHORT TERM CONTROLLED-ATMOSPHERE STORAGE
Authors: Drake S.R. , Ivanov S.K.
Published: February 2019

In 1989 and 1990, `Golden Delicious' apples from controlled-atmosphere (CA) storage (1% O2; 3% CO2) averaged 8.5 N firmer after 30 days and 13.5 N firmer after 60 days of storage than apples from regular-atmosphere (RA) storage. After 7 days of ambient storage, `Golden Delicious' apples from CA storage were 10.3 N firmer than apples from RA storage. Little change in color was evident in `Golden Delicious' apples from CA storage after 30 or 60 days, but a distinct increase in yellow color was evident in apples from RA storage after only 30 days. The quality (color, firmness, and acidity) of `Golden Delicious' apples stored for 30 days under CA and then 30 days under RA was superior to that of `Golden Delicious' apples after 60 days of RA storage and similar to that of `Golden Delicious' apples after 60 days of CA storage. `Granny Smith' apples, traditionally a very firm apple regardless of the type of storage, averaged 3.3 N firmer after 30 days of CA storage (1% O2; 1% CO2) and 5.8 N firmer after 60 days of CA storage when compared to apples from RA storage. Little change in color was evident in `Golden Delicious' apples regardless of storage length, but under ambient storage temperatures, `Golden Delicious' apples from CA storage maintained their green color longer. Titratable acidity of both `Golden Delicious' and `Granny Smith' apples depended on growing season, and neither `Golden Delicious' nor `Granny Smith' apples showed consistent trends in titratable acidity after either RA or CA storage.
CRYOPRESERVATION OF DORMANT BUDS FROM COLD-TENDER TAXA USING A MODIFIED VITRIFICATION PROCEDURE
Authors: Seufferheld Manfredo J. , Stushnoff Cecil , Fitzpatrick John , Forsline Philip L.
Published: February 2019

Cryopreservation of woody-plant, dormant buds may provide cost-effective, long-term, back-up conservation of germplasm for vegetatively propagated crops that are presently maintained as trees in field gene banks. Dormant buds can be recovered quickly by grafting to dwarfing rootstocks, thus producing flowers for breeding purposes, with minimum potential for inducing somaclonal variants. These attributes are essential to preserve the clonal integrity of unique gene combinations such as those found in tree fruit crops. Previous research has shown that dormant buds from cold-hardy apples can be recovered from storage in liquid nitrogen (LN) with high survival rates (80% to 100%) using controlled desiccation and slow freezing before immersing in LN. On the other hand, dormant buds from cold-tender taxa and buds collected at less than optimal stages for desiccation and freezing have much lower (0% to 50%) survival rates. We increased survival of cold-tender taxa by using a modified vitrification procedure. Dormant apple buds from tender and hardy cultivars were perfused with modified PVS [15% (w/v) ethylene glycol, 15% (w/v) propylene glycol, 7% (w/v) DMSO, and 15% (w/v) glycerol in 0.5 m sorbitol]. Toxicity from the PVS was reduced by dilution soaking in 1 m sorbitol, 0.2 m raffinose, and 15 mm CaCl2 before and after quench-freezing and slow-freezing cryopreservation. Up to 100% of some cold-tender taxa survived. In addition, xylem ray parenchyma tissues that supercool and are normally killed at about -40C with the desiccation protocol survived this vitrification procedure.
IN VITRO HARDENING OF STRAWBERRY, FRAGARIA ×ANANASSA, USING POLYETHYLENE GLYCOL-STAGE 3
Authors: Brown Aaron J.
Published: February 2019

Polyethylene glycol (PEG) was evaluated for its influence on hardening of in vitro-propagated `Fern' strawberries (Fragaria ×ananassa) when applied just before transplanting. Strawberries were micropropagated via shoot tips and grown in vitro until roots were well developed. Plantlets were then transferred onto filter paper bridges in liquid medium with 15% (w/v) of PEG-8000. After treatment in the medium for various periods, the plants were compared to the control (no PEG) for water loss from detached leaves, stomatal aperture, and survival rates after transplanting. Leaf epicuticular wax was also quantified. Overall, the in vitro PEG treatment was not successful in significantly increasing hardiness and survivability of the strawberry plants after transplanting from in vitro conditions to a soil medium. Osmotic stress was created, but apparently not for the time needed to increase survival. Further tests are needed to pinpoint the proper exposure time required to increase hardiness and survivability after transplanting plantlets. To increase survival, the time exposed to PEG should be 15, 18, or possibly 21 days.
ESTIMATING WATER REQUIREMENTS OF LANDSCAPE PLANTINGS
Authors: Costello L.R. , Matheny N.P. , Clark J.R.
Published: February 2019

Since it is unlikely that crop coefficients will be established for landscape plantings, a method to estimate landscape water requirements is proposed. By evaluating three factors that significantly influence water use-species planted, vegetation density, and site microclimate-and assigning numerical values to each, an estimate of a landscape crop coefficient (or landscape coefficient, KL) can be calculated. An estimate of evapotranspirational water loss for landscapes is then the product of the landscape coefficient multiplied by the reference evapotranspiration. This paper presents values for the above three factors and discusses the rationale for each. Examples using the landscape coefficient formula are included, as well as a discussion of special considerations relative to its use.
Short-term Flooding Affects Gas Exchange Characteristics of Containerized Sour Cherry Trees
Authors: Beckman Thomas G. , Perry Ronald L. , Flore James A.
Published: February 2019

The effects of short-term soil flooding on gas exchange characteristics of containerized sour cherry trees (Prunus cerasus L. cv. Montmorency /P. mahaleb L.) were studied under laboratory conditions. Soil flooding reduced net CO2 assimilation (A) within 24 hours. Net CO2 assimilation and residual conductance to CO2(gr′) declined to ≈30% of control values after 5 days of flooding. Effects on stomatal conductance to CO2 (gS) and intercellular CO2 (Ci) were not significant during the 5 days of treatment. Apparent quantum yield (Φ) gradually declined to 52% that of controls during these 5 days. In a second experiment, CO2 response curves suggested that, initially, stomatal and nonstomatal limitations to A were of about equal importance; however, as flooding continued, nonstomatal limitations became dominant.
Excised Twig Assay to Evaluate Cherry Rootstocks for Tolerance to Pseudomonas syringae pv. syringae
Authors: Krzesinska Elzbieta Z. , Azarenko Anita Nina Miller
Published: February 2019

Au excised twig assay was developed to evaluate cherry rootstocks (hybrids of Prunus avium L.; P. canescens Bois.; P. cerasus L.; P. fruticosa Pall.; P. mahaleb L.; P. pseudocerasus Lindl.) for their tolerance to Pseudomonas syingae pv. syringae van Hall. Twigs of `Napoleon', `Corum', and F12/1 in 1988 and 10 more rootstocks in 1989 were inoculated with water, one avirulent (K4), or one of three virulent strains (W4N54, AP1, and B-15) of bacteria at 105, 106, and 107 colony forming units (cfu)/ml in 1988 and with 107 cfu/ml in 1989. Evaluation of browning and gummosis at the inoculation site after incubation for 4 weeks at 15C and high relative humidity revealed no gummosis or browning on twigs inoculated with water or the avirulent strain. The amount of browning and gummosis induced by concentrations of 106 and 107 cfu/ml of the virulent strains was, in general, not different within genotypes. `Napoleon' and `Corum' had significantly higher browning and gummosis ratings in 1989 than F12/1 and the 10 rootstock selections, most of which did not differ from F12/1. Rootstocks Gisela (Gi.) 172-9 and Gi. 169-15 had higher incision browning than F12/1 in some instances.
Nitrogen Sources and Rates for Direct-seeded and Transplanted Head Lettuce
Authors: Walworth J.L. , Carling D.E. , Michaelson G.J.
Published: February 2019

Head lettuce (Lactuca sativa L.) cv. Salinas was produced in field trials in southcentral Alaska with varying planting dates, planting methods, N sources, and N application rates. Variables measured included head weight and diameter and harvest date. Nitrogen source had little effect on head weight. Direct-seeded lettuce produced heaviest beads from early plantings; transplants produced heaviest heads when planted in mid- to late season. Transplanting generally produced heavier heads than direct-seeding. Head weight of transplanted and direct-seeded lettuce was maximized with ≈112 kg N/ha. The data suggest that 112 kg N/ha may be suitable for lettuce direct-seeded or transplanted throughout the growing season.
Treatment of X-disease of Peaches Using Oxytetracycline Microinjection Capsules
Authors: Cooley Daniel R. , Tattar Terry A. , Schieffer Julianne T.
Published: February 2019

Oxytetracycline microinjection was assessed in four Massachusetts peach [Prunus persica (L.) Batsch] orchards where many trees were infected with X-disease. The injections significantly alleviated symptoms in all but the most severely diseased trees in the first year following treatment. This improvement was observed, to a lesser degree, the second season after treatment. Injection wounds did not callus and some damage to wood was observed around them, but after 2 years, there was no indication that injection wounds resulted in significant tree damage. Microinjection capsules offer an effective and more efficient injection treatment than existing methods.
Degree of Undercooling and Injury of Whole Potato Plants following Exposure to -4C for 6 or 12 Hours
Authors: Lindstrom Orville M. , Olson David J. , Carter John V.
Published: February 2019

Hardened and nonhardened whole plants of three potato species, Solanum tuberosum L., S. acaule Bitt., and S. commersonii Dun., and one interspecific cross, `Alaska Frostless' (S. tuberosum x S. acaule) were placed in a low-temperature chamber capable of maintaining -4 ± 0.5C for 6 or 12 hours. The chamber was designed to control the root temperature independently from the rest of the plant. Cold acclimation did not affect the ability of any of the potatoes tested to undercool (supercool). Solanum tuberosum and `Alaska Frostless' did not undercool for the times and temperatures tested and in all cases were killed. Whole plants of S. acaule and S. commersonii undercooled, in some cases, for up to 12 hours. When plants of S. acaule froze, they were severely injured, although their hardiness levels were reported to be lower than the temperature to which they were exposed in this study. Whenever leaves and stems of S. commersonii were frozen they were not injured. Once the soil was allowed to freeze, all plants, in all cases, were frozen.
Pleiotropic Effects of gri on Seed Coat and Flower Color in Common Bean
Authors: Bassett Mark J.
Published: February 2019

The effects of gri on seed coat and flower color were investigated in a study using Lamprecht line V0400 (PI 527735) as the known source of gri. Seed and flower color data were taken on observations of F2, BC1-F2, and BC2,-F2 populations from crosses of V0400 with the recurrent parent S-593. Segregation was observed for a unique flower color pattern: wing petals have a very pale tinge of blue (laelia), and the banner petal has two violet dots (≈3- to 4-mm diameter) on a nearly white background. This very pale laelia flower color cosegregates with gray-white seed coats produced by gri. Furthermore, the very pale laelia color depends on the action of V for expression and is extinguished by v, which produces pure white flowers. Thus, it was demonstrated that the very pale laelia flower color, for which Lamprecht tentatively proposed the gene symbol vpal, is not controlled by an allele at V but is a pleiotropic effect of gri. It was also demonstrated that Lamprecht line V0060 (PI 527717) carries vlae, not v, as indicated by the genotypic notes accompanying the Lamprecht seed collection.
Requirements for Seed Germination of Mexican Redbud, Evergreen Sumac, and Mealy Sage
Authors: Tipton Jimmy L.
Published: February 2019

Seed scarification and stratification (moist-prechilling) requirements of Mexican redbud [Cercis canadensis var. mexicana (Rose) M. Hopk.] and evergreen sumac (Rhus virens Gray) and the effects of temperature on final percent germination, maximum germination rate, and inflection time (time to maximum germination rate) for the above species plus seeds of mealy sage (Salvia farinacea Benth.) were investigated. Maximum predicted germination from a quadratic response surface was 95% after 62 minutes of concentrated sulfuric acid scarification plus 35 days of stratification for Mexican redbud, and 59% after 52 minutes of scarification plus 73 days of stratification for evergreen sumac. Mexican redbud germinated at 24 to 31C. Predicted optima for final percent germination, maximum germination rate, and inflection time were 100% at 28C, 30% germination per day at 31C, and 4 days at 29C, respectively. Evergreen sumac germinated at 21 to 31C. Final percent germination for this species declined with increasing temperature from a predicted maximum of 52% at 21C, whereas maximum germination rate increased with temperature to a predicted maximum of 69% germination per day at 31C. Inflection time was high at both extremes with a predicted minimum of 10 days at 25C. Mealy sage germinated at 21 to 34C. Predicted optima for final percent germination, maximum germination rate, and inflection time were 96% at 25C, 104% germination per day at 27C, and 3 days at 28C, respectively.
Changes in Pectic Fractions during Ripening- of Cider Apples
Authors: Mangas J.J. , Dapena E. , Rodriguez M.S. , Moreno J. , Gutiérrez M.D. , Blanco D.
Published: February 2019

Water-soluble pectin (WSP), chelator-soluble pectin (CSP), and hydrochloric acid-soluble pectin (HASP) were monitored in five Asturian apples (Malus domestics Borkh.) throughout ripening. The alcohol-insoluble solid content was found to decrease during ripening, while those of the WSP and CSP fractions increased in the final stages of ripening. This increase was probably at the expense of the HASP content, which had decreased by the end of the ripening period.
Use of Refractive Index to Monitor Changes in Sugar Content of Stored Sweetpotatoes
Authors: Walter William M.
Published: February 2019

The sugar content of five sweetpotato [Ipomoea batatas (L.) Lam.] cultivars (`Centennial', `Cordner', `Georgia Red', `Jewel', and `Sweet Red') was measured by high-performance liquid chromatography (HPLC) and compared to the sugar content of the cellular sap measured by refractive index (RI). The HPLC and RI sugar contents were measured at harvest, after curing, and during storage. Changes in the sugar content, as determined by the RI, were found to be linearly related to changes in the sugar content of cell sap and tissue, as measured by HPLC, indicating that this method can be used to monitor changes in postharvest total sugar content.
Controlling Relative Humidity in Modified Atmosphere Packages of Tomato Fruit
Authors: Shirazi Ahmad , Cameron Arthur C.
Published: February 2019

The feasibility of controlling relative humidity in modified atmosphere packages using compounds possessing Type III sorption isotherm behavior was studied. Ten grams each of dry sorbitol, xylitol, NaCl, KCl, or CaCl2 sealed with one maturegreen tomato (Lycopersicon esculentum L.) fruit at 20C in simulated packages for 48 days resulted in stable relative humidities of ≈75%, 80%, 75%, 85%, and 35%, respectively. Relative humidity was a function of the ratio of chemical to fruit mass. Relative humidities within control packages were in the range of 96% to 100% throughout the experiments. A simple system that uses spunbonded polyethylene pouches for the application of this humidity control method to packages is described. The storage life of packaged red-ripe tomato fruit at 20C was extended from 5 days using no pouch to 15 to 17 days with a pouch containing NaCl, mainly by retardation of surface mold development.
Freezing Tolerance of Avocado Leaves
Authors: McKellar M.A. , Buchanan D.W. , Ingram Dewayne L. , Campbell C.W.
Published: February 2019

Freezing tolerance and the lethal freezing temperature were determined for detached leaves of avocado (Persea americana Mill.) by either electrolyte leakage or visual appearance of browning. Leaves from field-grown trees of `Gainesville', `Booth8', and `Winter Mexican' in both Gainesville and Homestead, Fla., were evaluated. All cultivars in both locations survived ice formation in their tissue. Leaf tissue had a temperature limit (lethal freeze temperature) at and below which the tissue died. The lethal freezing temperature varied from -5.1 to -9.3C, depending on time of year and location. The lethal freeze temperature for a cultivar decreased over the fall and winter as temperatures decreased. Leaves of `Booth-8' and Winter Mexican' decreased 2.5 and 1.5C, respectively, in Homestead from 13 Nov. 1982 to 5 Feb. 1983. The plants growing at the lower temperature location (Gainesville) had lower lethal freeze temperatures. Leaves of `Gainesville' had a lethal freeze temperature of - 9.3C from trees at Gainesville and - 7.8C from trees at Homestead.
Temperature Cycling Periods Meet Growth and Tuberization in Potatoes under Continuous Irradiation
Authors: Cao Weixing , Tibbitts Theodore W.
Published: February 2019

Plants of the potato (Solanum tuberosum L.) cultivars Denali, Norland, Haig, and Kennebec were grown for 42 days under three temperature cycling periods (thermoperiods) with continuous irradiation in two repeated experiments to help determine if temperature cycling might be varied to optimize tuber development of potatoes in controlled environments. Thermoperiods of 6/6 hours, 12/12 hours and 24/24 hours were established with the same temperature change of 22/14C and same controlled vapor pressure deficit of 0.60 kPa. The thermoperiod of 24/24 hours significantly promoted tuber initiation but slowed tuber enlargement in all four cultivars, compared to the thermoperiods of 6/6 hours and 12/12 hours. `Denali' produced the highest tuber and total dry weights under the 6/6 hours thermoperiod. `Kennebec' produced the highest tuber dry weight under the 12/12 hours thermoperiod. Thermoperiods had no significant effect on shoot and root dry weights of any cultivars. The major effect of thermoperiod was on initiation and enlargement of tubers.
Tomato Fruit Quality and Shelf Life in Hybrids Heterozygous for the alc Ripening Mutant
Authors: Mutschler Martha A. , Wolfe David W. , Cobb Edward D. , Yourstone Kenneth S.
Published: February 2019

Fruit of tomato (Lycopersicon esculentum Mill.) hybrids heterozygous for the alc ripening mutation stored on average 60% (3.6 days) longer at 20C than that of their normal-ripening parents. There were no detrimental effects of the alc heterozygous condition on fruit color, firmness, or size. The background into which alc was introduced also affected fruit quality and shelf life. These results indicate hybrids heterozygous for the alc ripening mutant can produce commercially acceptable fruit with significantly longer shelf life than their normal-ripening parents.
Monitoring the Potassium Status of Greenhouse Tomatoes Using Quick Petiole Sap Tests
Authors: Coltman Robert R. , Riede Stacy A.
Published: February 2019

`Celebrity' tomatoes (Lycopersicon esculentum Mill.) were grown in peat–perlite under greenhouse conditions in two experiments with five levels of K (25, 50, 100, 200, and 300 mg·liter–1) in irrigation waters. In both experiments, aqueous petiole sap K concentrations (milligrams K per milliliter) were monitored weekly with colorimetric paper test strips. Variation in petiole sap K concentrations among plants was low among three-plant replicates (cvs of 9% to 11%). Petiole sap K concentrations varied considerably from week to week, but remained relatively constant over time at levels determined by external-feed K concentrations. Petiole sap K levels and marketable-fruit yield increased quadratically with increasing external K concentrations. Maximum yields were produced with 190 to 200 mg K/liter in external-feed solutions. Maximum marketable yields of ≈2.75 kg/plant occurred with =5.9 mg K/ml in petiole sap. Quick petiole sap K tests appear to be suitable for assessing the K status of greenhouse tomatoes.
Estimates of Self-pollination in Pecan Orchards in the Southeastern United States
Authors: Wood Bruce W. , Marquard Robert D.
Published: February 2019

Self-pollination was estimated in three Georgia pecan [Carya illinoinensis (Wangenh.) K. Koch] orchards. Selfing in two large orchards lacking an interplanted complementary pollinizer (one orchard being comprised of `Curtis' and the other `Moneymaker') was estimated to be at least 3% and 49%, respectively. A `Cheyenne' orchard containing `Stuart' as a complementary pollinizer at 5% density was estimated to have had at least 14% and 42% of ripened nuts derived from selfing in two consecutive years. These estimates suggest self-pollination may reduce yield in pecan orchards in the southeastern United States.
Additional East European Pyrus Germplasm with Resistance to Pear Psylla Nymphal Feeding
Authors: Bell R.L.
Published: February 2019

Eight cultivars and wild seedlings of pear (Pyrus spp.) from Eastern Europe were evaluated for resistance to feeding by early instar pear psylla [Cacopsylla pyricola (Foerster)] in a 24-hour assay. All were compared to a susceptible control, `Bartlett' (P. communis L.), and to a moderately resistant control, NY10352 (P. communis × P. ussuriensis Maxim. BC hybrid). Three P. communis cultivars, Bartjarka (PI 483391), Lucele (PI 483402), and Kajzerka (PI 506387), and a wild seedling (PI 506381) of undetermined species, exhibited a high degree of host resistance, measured as reduced frequency of feeding and increased either mortality or movement off of the plants.
Short- and Long-term Heat Stress Effects on Phytophthora Root Rot of Hibiscus
Authors: Lyles J.L. , MacDonald J.D. , Burger D.W.
Published: February 2019

Roots of hydroponically grown Hibiscus Rosa-sinesis L. cuttings were exposed to 22, 30, 40, or 50C for 20 minutes, after which they were inoculated with zoospores of Phytophthora parasitica Dastur. Visual assessment of root discoloration and culturing of randomly selected root pieces 10 to 13 days after treatment showed that roots exposed to 40 or 50C had a significantly higher incidence of infection than those exposed to 20 or 30C. Plants were also grown in pots containing University of California (UC) mix or washed, graded sand and exposed to solar radiation for 1 day or 3 weeks, respectively. Root systems of plants in direct sunlight heated to 52C, while roots of shaded plants heated to 40C. Assessment of infection severity was done visually or by means of a Phytophthora-specific antibody probe. In all experiments, infection severity was highest in sun-exposed plants and was insignificant to moderate in shaded plants.
Shoot-tip Culture of Muscadine Grape to Eliminate Pierce's Disease Bacteria
Authors: Robacker C.D. , Chang C.J.
Published: February 2019

Pierce's disease, caused by the bacterium Xylella fastidiosa Wells et al., is widespread among muscadine grapes (Vitus rotundifolia Michx). To determine whether shoot-tip culture would be effective in eliminating X. fastidiosa, shoot tips of infected grape plants were cultured on Murashige and Skoog medium amended with 9 μm benzyladenine. Shoots and callus that developed tested negative for the presence of X. fastidiosa. Shoot-tip culture appears to be a promising method of obtaining muscadine grape plants free of Pierce's disease. Chemical name used: 6-benzylaminopurine (benzyladenine).
Analysis of Consumer Purchases of Floral Products in Supermarkets
Authors: Behe Bridget K. , Prince Timothy A. , Tayama Harry K.
Published: February 2019

Survey analysis of 510 floral product consumers in Ohio supermarkets identified 34 factors that affect floral purchasing. Responses to 106 survey questions were factor-analyzed using a principal component analysis with varimax rotate that yielded 34 independent factors, accounting for 64% of the total variance. Factors were grouped into five major categories: product, consumer, store, use (gift), and use (location) factors. The analysis condensed the domain of consumer floral purchasing issues into fewer factors that represent the most important influences on floral buying decisions. The factors are useful in market segmentation and were used to define five market segments of supermarket-floral customers.
Importance for the U.S. Pecan Industry of Communicating about Quality
Authors: Florkowski W.J. , Purcell J.C. , Hubbard E.E.
Published: February 2019

Several standards for pecan [Carya illinoinensis (Wangenh.) K. Koch] grades and the relationship between selected quality attributes and prices indicated the complexity of communicating about quality attributes. Clear communication about quality attributes preferred by end users within the pecan industry and horticulturists facilitates the improvement of cultivars and strengthens the competitive position of the industry. A survey of Georgia pecan growers provided information about knowledge and perceived adequacy of pecan quality standards. Logit models were used to identify variables influencing knowledge of pecan grades and their perceived adequacy. Estimation results suggest that larger and more experienced growers were more familiar with the U.S. Dept. of Agriculture standards for grades than small and new growers. The geographical location of a grower did not significantly affect the results. Knowledge of quality attributes demanded by the market requires familiarity with standards for grades and with industry practices to develop improved pecan cultivars.
PREHARVEST FACTORS INFLUENCING POSTHARVEST QUALITY OF TROPICAL AND SUBTROPICAL FRUIT
Authors: Arpaia M.L.
Published: February 2019

Although postharvest handling schemes have improved during recent years, it is still possible to observe considerable variability in fruit quality between individual lots. Preharvest factors such as irrigation, nutrition and pest management practices, as well as rootstock and environmental variables, may greatly influence quality after harvest and may well account for some of the differences between individual lots. The influence of preharvest factors on postharvest quality of tropical and subtropical fruit will be discussed using pertinent examples from the literature. Emphasis will be given to those factors which can be manipulated to improve quality.
CARBOHYDRATE AND PROTEIN BALANCE DURING EPISODIC GROWTH IN LIGUSTRUM JAPONICUM
Authors: Kuehny Jeff S. , Halbrooks Mary C.
Published: February 2019

Research defining actual changes in weight gain of roots and shoots during growth episodes of woody ornamentals is limited. The objective of this study was to develop a better understanding of the patterns of root and shoot growth, nitrogen uptake, and changes in carbohydrate and protein content of Ligustrum japonicum, an episodic species. Shoot elongation and lateral root formation were synchronous. The greatest increase in shoot percent of whole plant fresh weight occurred after shoot elongation however, and the greatest increase in root percent of whole plant fresh weight occurred during shoot elongation. Nitrate uptake was highest during shoot elongation and lateral root formation. Carbohydrate and protein content also varied with each episode of growth.
COVER CROP AND NITROGEN FERTILIZER RATE INFLUENCES ON YIELDS OF SEQUENTIALLY PLANTED VEGETABLES
Authors: Bandele Owusu A. , Javius Marion , Belvitt Byron , Udoh Oscar
Published: February 2019

Fall-planted cover crops of hairy vetch (Vicia villosa Roth), Austrian winter pea (Pisum sativum subsp. arvense L. Poir), and crimson clover (Trifolium incarnatum L.) were each followed by spring-planted 'Sundance' summer squash [Cucurbita pepo var. melopepo (L.) Alef.] and 'Dasher' cucumber (Cucumis sativus L.). Squash and cucumber crops were followed by fall 'Florida Broadleaf mustard green [Brassica juncea (L.) Czerniak] and 'Vates' collard (Brassica oleracea L. Acephala group), respectively. The same vegetable sequences were also planted without benefit of cover crop. Three nitrogen (N) rates were applied to each vegetable crop. Squash following winter pea and crimson clover produced greater yields than did squash planted without preceding cover crop. Cucumber following crimson clover produced the greatest yields. No cover crop effect was noted with mustard or collard. Elimination of N fertilizer resulted in reduced yields for all crops, but yields of crops with one-half the recommended N applied were generally comparable to those receiving the full recommended rate.
FIELD TESTS EVALUATING PRE- AND POST-PLANT NITROGEN FERTILIZER PROGRAMS FOR MUNG BEAN PRODUCTION
Authors: Murray Mike , Young Carrie
Published: February 2019

Field tests were conducted in commercial mung bean (Vigna radiata) fields in 1986, 1987, and 1989. The objective of these tests were to: determine optimum nitrogen fertilizer rates; evaluate preplant, postemergence or split applications of nitrogen; and develop data to utilize petiole sampling as an analytic technique to quantify plant nitrogen status.

Seed yields were significantly increased two of the three years by the addition of nitrogen fertilizers. Over three years, the addition of 40-120 pounds of nitrogen per acre resulted in an average seed yield increase of 14-37 percent, compared to an untreated control. Maximum yields were obtained with eighty pounds of nitrogen per acre. Within specific rates, there was a trend for preplant or split applications to result in the greatest yield increases.

Petiole nitrate levels did not appear to be a reliable indicator of plant nitrogen status, with wide differences between rates in different years. An average for the three-year test, six weeks after crop emergence, was 1270 ppm for the control and 2340 ppm for treatments receiving 80 pounds of nitrogen per acre.
IN VITRO SHOOT REGENERATION FROM INTERNODE SEGMENTS AND INTERNODE - DERIVED CALLUS OF BLUEBERRY (VACCINIUM SPP.)
Authors: Hruskoci Jim , Read Paul E.
Published: February 2019

In an effort to increase somaclonal variation in blueberry, a protocol was developed to regenerate viable shoots from internode segments. The explant consisted of the last-formed, fully developed internode taken from 3 different genotypes of Vaccinium grown in vitro. Explants were cultured 6 weeks on Zimmerman's Z-2 medium supplemented with 2iP, zeatin, thidiazuron, kinetin, or BA at concentrations of 5, 25, 50, and 100 uM. Explant response to the treatments varied and included: no response, callus growth only, callus growth and subsequent shoot formation originating from the callus mass, and adventitious shoot formation directly from the internode segment without an intervening callus. Greatest shoot regeneration (20-25 shoots/explant) was obtained on medium supplemented with zeatin at 5, 25, and 50 uM, however treatment response was not consistant across all genotypes. Regenerated shoots could be readily sub-cultured, rooted in soil mix and will be evaluated for somaclonal variation.
CALOGENESIS AND ORGANOGENESIS OF SOMATIC MATERIAL FROM APPLE SEEDLINGS (MALUS DOMESTICA BORKH) AS AFFECTED BY SOURCE MATERIAL AND DARK PERIOD.
Authors: de L. Fortes Gerson R. , Teixeira Silvio L.
Published: February 2019

The aim of this work was to study different apple of somatic material as callus and adventitious shoots are concerned, for further utilization in the research of somaclonal variation. The somatic materials were: leaf discs, cotyledons and hypocotyls of Gala apple seedlings, cultivated in a MS medium added by B5 vitamins in addition to (in mg/l): BAP (1,0), NAA (0,5) mio-inositol (100,0) sucrose (30,0 g/l) and solidified in agar (6,0 g/l). The several times of explant exposition to the dark affected the final callus weight. Callus weight derived from leaf discs were higher than those for cotyledons and hypocotyls. Explants exposed directly under light or up to two weeks in the dark showed less percentage of regenerative callus as compared to those of three weeks in the dark. The leaf explants presented the highest percentage of regenerative callus. The least response was obtained for those derived from hypocotyls. The highest number of adventitious shoots was obtained keeping the explants three weeks in the dark as compared to directed light exposition.
OZONE GRADIENTS, PHOTOSYNTHESIS AND YIELD IN PLUM
Authors: Grantz D.A , Retzlaff W.A. , Williams L.E. , DeJong T.M.
Published: February 2019

Models indicate that ozone inhibits carbon assimilation largely in the upper canopy, due to light and ozone gradients. We document yield reductions and ozone gradients in Casselman plum in open-top ozone fumigation chambers. Ambient air (12 hr mean ozone = 0.050 ppm), charcoal filtered air (0.034 ppm) and ambient air plus added ozone (0.094 ppm) were circulated in the chambers. Additional trees grew outside the chambers (0.058 ppm). Outside the chambers large vertical and horizontal gradients in ozone within the canopy were documented, but these were absent in the chambers. Ozone decreased leaf photosynthesis by 31% and 58%, and fruit yield by 20% and 66%, in the ambient and ozone enriched relative to filtered chambers. Despite altered gradients, yield and photosynthesis of exposed leaves were similar inside and outside the chambers in ambient air. Compensatory changes in leaf function may be involved.
STIMULATING LANDSCAPE AWARENESS FOR FUTURE GENERATIONS
Authors: Hatchell Michael , Hague Mary , Caldwell Judy
Published: February 2019

The City of Clemson, South Carolina recently received funding from America the Beautiful to develop a community/government/educational partnership. The purpose of this project was to promote tree planting initiatives and awareness for future generations as well as to enhance our city and its roadsides. The project involved completing a tree inventory and landscape design for Highway 123, a major highway into Clemson. Presentations were made to city officials and approvals obtained by the highway department before implementation took place. Over 100 trees were planted and an educational pamphlet was published to illustrate the streetscape project and to serve as a guide for city officials. My presentation outlines the goals, methodology and results of this project.
CERTIFICATION FOR PROFESSIONAL HORTICULTURIST
Authors: Miller Mark e.
Published: February 2019

Consumers of horticultural services deserve a standard to insure that practicing horticulturist have the necessary education, experience and continuing education to solve wide ranging problems from production horticulture to landscape management in an effective and environmentally conscious manner. A Certified Professional Sub-Board was established as a part of the American Registry of Certified Professionals in Agronomy, Crops, and Soils (ARCPACS) in November 1991. The ASHS support of certification of practicing horticulturist will primarily benefit those holding BS degrees. Forty percent of the American Society of Agronomy (ASA) 12,500 members highest earned degrees are BS and/or MS. By contrast only 5% of the 5,000 ASHS members are at the BS and/or MS levels. It is evident that ASA has been more perceptive of the needs of their undergraduate degree holders than ASHS. With the advent of CPH we can now begin to meet the needs of our BS and/or MS degree holders. Economic analysis reveals certification is beneficial to both the horticulturist and consumers.
LONG DAYS PROMOTE FLOWERING OF ARMERIA MARITIMA
Authors: Lehmann J.T. , Albrecht M.L.
Published: February 2019

Armeria maritima was studied to provide guidelines for flowering potted plant production. Seed and vegetatively propagated plants were exposed to 9-hr, 13-hr, or 17-hr photoperiods. Flowering was enhanced under the 13-hr and 17-hr photoperiods. Peduncle and leaf length were shorter, and plants were more compact under short days (SD, 9-hr photoperiod) than under long days (LD). When grown under SDs then moved at monthly intervals to LDs, the degree to which the compact growth habit (CH) was expressed was dependent upon the length of exposure to SDs. Plants with the CH produced fewer inflorescences than full growth habit plants.

Plants held in cold storage (4C) flowered more profusely under LDs, but had a delay in flowering. There was more uniform flowering for plants held in cold storage than those held in a cool greenhouse (7C night temperature).
FACTORS INFLUENCING FLOWER BUD ABSCISSION OF POTTED CAMELLIA
Authors: Lee Jong Suk , Song Cheon Young
Published: February 2019

It has been a serious problem that flower buds of camellia (Camellia spp.) drop very easily when they are grown under unfavourable indoor conditions. To examine the factors affecting flower bud abscission, some cultivars of potted camellia (Camellia japonica L.) moved to various indoor conditions from greenhouse after flower buds were well developed. In general, double flowering cultivars showed more flower bud abscission than single flowering cultivars. Relative humidity (RH) severely influenced flower bud abscission. In `Beniodome' camellias, flower bud abscission reached to 90% under arid condition (30% RH) which resulted in very poor flowering (8%), whereas flower bud abscission recorded only 5% under humid condition (80% RH) which resulted in abundant flowering (90%). Flower bud abscission of camellias was little influenced by light intensity. Plants applied with 500 ppm ethephon produced a lot of ethylene and abscised all flower buds within a month. Ethylene accelerated the development of the abscission layer of camellia pedicels. Spray with 2 mM silver thiosulfate (STS) effectively prevented flower bud abscission of potted camellias. Polygalacturonase activity of abscission zones was correlated with the increase of flower bud abscission in camellias.
ENHANCED GERMINATION OF CELERY AT STRESS TEMPERATURE VIA SOLID MATRIX PRIMING
Authors: Cantliffe Daniel J. , Oiao Ping , Parera Carlos A.
Published: February 2019

The high temperature severely reduces seed germination, emergence, and seedling uniformity in celery (Apium graveolens L.). Celery seeds were primed via solid matrix priming (SMP) using water or 1% sodium hypochlorite (NaOCl) solution at 1, 2, 3 or 4 ml rate for 2, 4, 6, 8, 10, 12 and 14 days. Moisture content of the seeds was calculated for each priming treatment and time interval. After priming, the seeds were dried back to the original dry weight. The germination percentage was calculated for each treatment at two different temperatures (15 and 30C). The seed primed with NaOCl gained significantly less moisture during priming than the water treatment. Seeds primed with NaOCl had significantly greater germination at both 15 and 30C, compared to seeds primed with water. The germination percentage of non-primed seeds was 83% and 2% at 15C and 30C, respectively. The final germination percentage at 30C was increase to 85% when the seeds were primed with 3 ml of NaOCl for 14 days. The combination of SMP with NaOCl significantly reduced the negative effect of high temperature on celery seed germination.
QUILCHIUHCAYOTL, THE CHILDREN'S HORTICULTURE COURSE
Authors: Hernandez Z.C.C. , Balcazar S.T.
Published: February 2019

QUILCHIUHCAYOTL is the name of the children's course that is given in the botanic garden of the Universidad Nacional Autonoma de Mexico. This nahuatl name means “Orchard Culture”. It was initiated 20 years ago as a summer's Course of 1 month duration. Both Horticultural activities and Mexican Cultural Aspects are stressed. In order to accomplish these objectives, we have designed several educational materials and games.
FARMER'S BOOKSHELF™: HYPERMEDIA INFORMATION SYSTEM TO RECOMMEND GROUND COVERS
Authors: Kobayashi Kent D. , Bittenbender H.C.
Published: February 2019

Hawaii has had a large growth in housing, and with the reduced lot sizes of single family dwellings has come interest in using ground covers to landscape limited areas. As residential areas are being located on less desirable lands, there is a need to select ground covers that do well in these areas. The objective of this study was to develop a hypermedia information system to recommend ground covers and to obtain information on individual ground covers. Using the software HyperCard® on the Macintosh® computer, we developed a system that uses the idea of index cards with information being stored on separate screens called “cards.” Using a mouse, the user navigates from one card to another by clicking on a “button” on the card. The user may select up to four criteria from 33 criteria including plant height, elevation, soil moisture, flower color, erosion control, and shade. The program then finds which of 48 ground covers meet the desired criteria and provides information on these ground covers. This easy-to-use system requires no typing except to enter a word to search for. The user can quickly browse for the desired information and save it as a text file or print it. The Farmer's Bookshelf™ provides a tool for extension agents and growers to obtain easily vitally needed information. The program has further application for landscape companies, Master Gardener programs, and in horticultural courses.