bluuebunny/crossref_metadata_2025 huggingface dataset:
Error in Interpreting Field Chlorophyll Fluorescence Measurements: Heat Gain from Solar Radiation
Authors: Marler Thomas E. , Lawton Patrick D.
Published: February 2019

Temperature and chlorophyll fluorescence characteristics were determined on leaves of various horticultural species following a dark adaptation period where dark adaptation cuvettes were shielded from or exposed to solar radiation. In one study, temperature of Swietenia mahagoni (L.) Jacq. leaflets within cuvettes increased from ≈36C to ≈50C during a 30-minute exposure to solar radiation. Alternatively, when the leaflets and cuvettes were shielded from solar radiation, leaflet temperature declined to 33C in 10 to 15 minutes. In a second study, 16 horticultural species exhibited a lower variable: maximum fluorescence (Fv: Fm) when cuvettes were exposed to solar radiation during the 30-minute dark adaptation than when cuvettes were shielded. In a third study with S. mahagoni, the influence of self-shielding the cuvettes by wrapping them with white tape, white paper, or aluminum foil on temperature and fluorescence was compared to exposing or shielding the entire leaflet and cuvette. All of the shielding methods reduced leaflet temperature and increased the Fv: Fm ratio compared to leaving cuvettes exposed. These results indicate that heat stress from direct exposure to solar radiation is a potential source of error when interpreting chlorophyll fluorescence measurements on intact leaves. Methods for moderating or minimizing radiation interception during dark adaptation are recommended.
Low-temperature Storage for Quality Preservation and Growth Suppression of Broccoli Plantlets Cultured in Vitro
Authors: Kubota Chieri , Kozai Toyoki
Published: February 2019

Broccoli (Brassica oleracea L. Botrytis Group `Ryokurei') plantlets, cultured photoautotrophically (without sugar in the medium) in vitro for 3 weeks at 23C and 160 μmol·m–2·s–1 photosynthetic photon flux (PPF), were stored for 6 weeks at 5, 10, or 15C under 0 (darkness) or 2 μmol·m–2·s–1 PPF (continuous lighting) supplied by fluorescent lamps (white light). Dry weight of the plantlets stored for 6 weeks at 5 or 10C in light was not significantly different from that of the plantlets before storage. Dry weight of the plantlets decreased as temperature increased and was maintained at higher levels in light than in darkness. Chlorophyll concentrations of the plantlets were higher at the lower temperatures. Chlorophyll fluorescence kinetics indicated higher activities of chlorophyll of the plantlets stored in light than in darkness. Lighting at as low as 2 μmol·m–2·s–1 PPF was important to preserve photosynthetic and regrowth abilities and dry weight of the plantlets during low-temperature storage.
Durian Fruit Dehiscence—Water Status and Ethylene
Authors: Sriyook Siriphun , Siriatiwat Somboon , Siriphanich Jingtair
Published: February 2019

Immature and mature durian (Durio zibethinus Murr.) fruit dehiscence was studied. Fruit were stored at 27C and 65% or 95% relative humidity, with or without 24-hour exposure to 100 ppm ethylene. Low relative humidity and ethylene increased fruit dehiscence. Spraying fruit with 100 ppm GA3 delayed dehiscence but allowed pulp ripening to continue. The plant-growth regulators IBA; 2,4-D; 2,4,5-T; BAP; daminozide; and mepiquat chloride had no consistent effects on fruit dehiscence. Various coating materials delayed dehiscence and ripening; a sucrose fatty acid ester at 1% concentration gave the best result. All coating materials reduced weight loss 7% to 14% below that of the control fruit. Fruit coated with the sucrose fatty acid ester and 100% apple wax had higher internal CO2 levels than fruit coated with any other coating. Ethylene is more important in durian fruit dehiscence than weight loss. Chemical names used: 3-indolebutyric acid (IBA); 2,4-dichlorophenoxyacetic acid (2,4-D); 2,4,5-trichlorophenoxyacetic acid (2,4,5-T); 6-benzylaminopurine (BAP); succinic acid-2,2-dimethyl hydrazide (daminozide); 1,1-dimethyl-piperidinium chloride (mepiquat chloride); gibberellic acid (GA3).
Incidence of Stem Pitting of Lovell Rootstock and Own-rooted `Redhaven' and `Cresthaven' Peach Trees
Authors: Byers Ross E. , Yoder K.S. , Lyons C.G.
Published: February 2019

Own-rooted `Redhaven' and `Cresthaven' peach [Prunus persica (L.) Batsch.] trees and `Redhaven' and `Cresthaven' on Lovell seedling rootstock were planted in fumigated and nonfumigated areas of a site where peach trees previously displayed peach stem-pitting (PSP) symptoms. The combined incidence of stem pitting of the `Redhaven' and `Cresthaven' peach trees was 16% on nonfumigated soil in the 10 years of the study. The combined stem-pitting incidence of own-rooted trees (9.1%) was significantly lower than on Lovell roots (22.1%). Incidence of PSP in the adjacent fumigated areas was relatively low (1% Lovell and 4% own-rooted) and, therefore, precluded a comparison of own-rooted and Lovell-rooted trees. Within affected sections of rows, 67% of the `Cresthaven'/Lovell and 64% of the `Redhaven'/Lovell trees had PSP symptoms, but only 25% of own-rooted `Cresthaven' and 18.8% of own-rooted `Redhaven' trees were symptomatic. Although these data suggest that rooted cuttings of these cultivars may be less susceptible to stem pitting, the use of rooted cuttings does not eliminate fumigation as a means of providing acceptable stem-pitting management in a heavily infested site.
Brushing Reduces Thrips and Aphid Populations on Some Greenhouse-grown Vegetable Transplants
Authors: Latimer Joyce G. , Oetting Ronald D.
Published: February 2019

`Sunny' tomato (Lycopersicon esculentum Mill.), `Black Beauty' eggplant (Solanum melongena var. esculentum L. Nees.), or `Sugar Baby' watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] were nontreated, subjected to brushing (20 strokes twice daily) or drought conditioning (2 hours daily wilt), or maintained undisturbed using ebb-and-flow irrigation. One week after brushing or drought conditioning, plants were inoculated with western flower thrips (Frankliniella occidentalis Pergande) or green peach aphid (Myzus persicae Sulzer). Brushing and drought conditioning reduced plant height and shoot dry weight of all crops. Brushing of all three species generally reduced the number of thrips, as indicated by number of feeding scars or percent leaf area damaged. Drought conditioning did not affect thrips populations consistently. Undisturbed plants grown with ebb-and-flow irrigation exhibited the greatest damage from thrips. Brushing reduced the number of aphids on tomato relative to the nontreated controls. Drought did not reduce aphid populations consistently on any crop. Brushing for height control may be advantageous in an integrated pest-management program to control aphids and thrips.
Growth and Landscape Establishment of Pyracantha and Juniperus after Application of Paclobutrazol
Authors: Ruter John M.
Published: February 2019

The long-term effects of paclobutrazol applied to container-grown `Mojave' pyracantha (Pyracantha ×) and `San Jose' juniper (Juniperus chinensis L.) were investigated. Paclobutrazol was applied as a drench to container-grown (2.8 liter) plants at the rates of 0, 5, 10, 20, and 40 mg a.i./pot in June 1991, and plants were transplanted to the field in Feb. 1992. Pyracantha plant height, shoot and root dry weight, and total biomass (shoot dry weight + root dry weight) decreased quadratically as rate of paclobutrazol increased during nursery production. Paclobutrazol had no effect on plant height or shoot dry weight of Juniperus, although width indices were reduced. Ratings for root quality for Juniperus in containers increased as rate of paclobutrazol increased. After 9 months in the landscape, paclobutrazol still influenced plant height, width, and shoot dry weight for Pyracantha but had no effect on Juniperus. As rate of application increased, fruit retention on Pyracantha increased. Paclobutrazol applied as a container medium drench at 5 mg a.i./pot was excessive during nursery production of Pyracantha and Juniperus. Chemical name used: [(2RS, 3RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-yl)penten-3-ol] (paclobutrazol).
The Genetic Composition and Tetrasomic Inbreeding Coefficients of Highbush Blueberry Cultivars
Authors: Ehlenfeldt Mark K.
Published: February 2019

Inbreeding coefficients were calculated for highbush blueberry (Vaccinium corymbosum L.) cultivars based on a tetrasomic inheritance model. This model yielded lower inbreeding coefficients than previous calculations based on a disomic tetraploid inheritance model. Recent trends in breeding have resulted in significant use of V. darrowi Camp as a source of low-chilling germplasm for use in the southern United States. There is also a trend toward increased inbreeding in several crosses from which recently released cultivars have been derived. Increased inbreeding coefficients do not represent a detrimental situation in blueberry per se.
A Flexible Function for Regressing Asymptotically Declining Responses of Plant Growth to Growth Retardants
Authors: Kawabata Osamu , DeFrank Joseph
Published: February 2019

A modified power function, y = (A + B·x)–C, was developed for determining the relationship between plant growth and growth retardant treatment. This function accounts for the plant response characteristics by incorporating three coefficients: A, growth level of the nontreated plants; B, the degree of growth reduction; and C, the smallest effective dose of the growth inhibitor. The function accounted for 97% of the variation in purple nutsedge (Cyperus rotundus L.) leaf length as a function of the amount of a growth retardant applied. The procedure resulted in a smaller error sum of squares than several common nonlinear functions because of its greater shape flexibility.
MINIMIZING ENVIRONMENTAL STRESS IN FIELD ESTABLISHMENT OF VEGETABLE CROPS IN THE SOUTHWESTERN U.S.
Authors: Hartz T.K.
Published: February 2019

Overcoming environmental stresses during seedling establishment is crucial to successful vegetable production. In the irrigated production areas of the southwestern United States, stress most often is related to unfavorable temperature, soil or water salinity, or poor soil structure; it is frequently difficult to separate the effects of these stresses, since they may all be present to some significant degree. Growers use a variety of techniques to ameliorate these conditions. The use of sprinkler irrigation for stand establishment has become a widespread practice; sprinkling moderates soil temperature, minimizes salinity in the zone of germination, and reduces soil crusting. By modifying bed configuration, growers have been able to increase soil temperature to stimulate germination. Various chemical and physical treatments have proven effective in reducing soil crusting. The use of transplants has expanded for many crops, both as a means to circumvent seedling establishment problems and as a technique to obtain earliness.
PHYSIOLOGICAL APPROACH TO SEED ENHANCEMENT
Authors: Wilson Dale
Published: February 2019

Purchasers of high-value seeds expect strong, uniform, and reliable germination and establishment, even under stress. Enhancement refers to postharvest processes applied to the seed to improve performance. Most enhancement methods involve controlled hydration. In moisturization, water activity is increased up to the 0.6 to 0.7 range, and the seed is not redried before marketing. Moisturization reduces rehydration stress when the seed is sown. Priming methods include a diverse set of procedures that increase water activity beyond -0.9, hydrating membranes and, to various extents, physiologically activating the seed. After priming, seeds are redried to water activities below 0.7 to prevent fungal growth. Various hypotheses about why priming works will be presented.
ROADSIDE MONITORING OF Pb, Cd, Zn, Mn, AND Cu ACCUMULATION IN PLANTS AND SOIL AT ZION NATIONAL PARK, UTAH
Authors: Johanson M.R. , Williams C.F.
Published: February 2019

We conducted a preliminary field study that examines the accumulation of Pb, Cd, Zn, Mn, and Cu in plants and soil along a roadway in Zion National Park. The study is designed to determine the effects of motor traffic on the accumulation of these heavy metals in various plant species and soil during 1 year and to determine if these accumulations decrease as you move away from the roadway. Preliminary results indicate that the amount of Pb, Cd, Zn, Mn, and Cu concentrations found are a function of the number of vehicles passing during a year and the distance from the roadway. Higher concentrations of these heavy metals are found in areas close to the road and in areas where traffic is moving slowly or even stopped. The heavy metal concentrations decreased as the distance from the roadway increased, and the speed of passing vehicles increased.
Responses of Aster, Dusty Miller, and Petunia Seedlings to Daily Exposure to Mechanical Stress
Authors: Autio Janne , Voipio Irma , Koivunen Taina
Published: February 2019

Seedlings of aster [Callistephus chinensis (L.) Nees], dusty miller [Senecio bicolor (Willd.) Tod.], and petunia (Petunia Juss.) were subjected to brushing with burlap in two experiments. The spring experiment tested the daily duration of brushing (60, 120, or 180 minutes per day) and the autumn experiment tested the stimulus of brushing (brushing for 2 hours with single-layer, double-layer, or triple-layer burlap). Brushing was done with slow-moving apparatus. The increase in daily brushing duration led to a greater reduction of growth, although differences between the species were noted. Aster showed a growth reduction after 20 days of treatment, whereas dusty miller and petunia took longer to respond. Aster and petunia responded significantly even to the shortest daily brushing duration, whereas dusty miller needed 2 hours per day to achieve any significant growth reduction. Increasing the brushing stimulus resulted in injuries to aster leaves in autumn. Brushing with double-layer burlap caused maximum growth reductions in all the species. Brushing most clearly reduced the growth of dusty miller and petunia in autumn, but aster showed similar growth reductions in spring and autumn.
Rooting `Yoshino' Cryptomeria Stem Cuttings as Influenced by Growth Stage, Branch Order, and IBA Treatment
Authors: Jull Laura G. , Warren Stuart L. , Blazich Frank A.
Published: February 2019

Stem cuttings of `Yoshino' Japanese cedar [Cryptomeria japonica (L.f.) D. Don `Yoshino'], consisting of tips (terminal 20 cm) of first-order laterals, distal halves (terminal 10 cm) of tips of first-order laterals, and proximal halves (basal 10 cm) of tips of first-order laterals, or tips (terminal 10 cm) of second-order laterals, were taken on four dates that represented four growth stages (softwood, semi-hardwood, hardwood, and pre-budbreak). The cuttings were treated with 0, 3000, 6000, or 9000 mg IBA/liter. Branch order affected all rooting measurements at each growth stage. Regardless of growth stage, tips of and proximal halves of first-order laterals containing lignified wood had the highest percent rooting, root count, total root length, root area, and root dry weight. Hardwood tips of and semi-hardwood proximal halves of first-order laterals exhibited the highest overall rooting (87%), followed by softwood proximal halves of first-order laterals (78%). Rooting of distal halves of first-order laterals and tips of second-order laterals never exceeded 55% and 34%, respectively, at any growth stage. IBA treatment influenced percent rooting, root count, total root length, root area, and root dry weight of semi-hardwood, hardwood, and pre-budbreak cuttings, except for root dry weight of semi-hardwood cuttings. IBA had no affect on softwood cuttings. Chemical name used: 1H-indole-3-butyric acid (IBA).
Screening Sweet Cherry Selections for Dormant Floral Bud Hardiness
Authors: Kadir Sorkel A. , Proebsting Edward L.
Published: February 2019

In Dec. 1990, sweet cherry (Prunus avium L.) selections varied in floral bud kill from 9% to 92% following exposure to severe cold. In the following winter, the hardiness of two hardy and two tender selections was analyzed by differential thermal analysis (DTA) to screen selections for hardiness. In a mild winter, when buds remained at their minimum hardiness level, the hardy selections consistently were > 2C hardier than the tender selections. About one-half of that hardiness difference was associated with differences in tissue water content, the other half with unknown factors. Buds of the tender selections began to develop earlier and bloomed earlier than the hardy selections. DTA analysis of floral bud populations separated selections that clearly differed in floral bud hardiness.
A Simple Technique to Randomize and Label Large Experimental Plantings
Authors: Okie W.R. , Joyner W.R. , Beckman T.G.
Published: February 2019

Large field plantings are often difficult to label and to plant randomly. A DOS computer program was developed in SAS and BASIC to randomize lists of experimental factors and print sorted paper labels to apply to trees or plants. Tagged trees can be resorted readily by block or row to speed planting. The computer lists are useful for plot verification and subsequent data collection, especially if data are collected and inputted directly to a computer. Copies of the programs are available from W.R. Joyner if a formatted diskette and self-addressed mailer are supplied.
Determination of Injurious Phosphorus Levels in Poinsettias
Authors: Whipker Brian E. , Hammer P. Allen
Published: February 2019

Eight poinsettia (Euphorbia pulcherrima Wind.) cultivars (`Angelika White', `Celebrate 2', `Dark Red Hegg', `Jingle Bells 3', `Pink Peppermint', `Red Sails', `Supjibi', and `V-14 Glory') were grown in root medium amended with six triple superphosphate rates of 0.39,0.78, 1.55,3.11,4.66, and 6.21 kg P/m3. Root medium and foliar samples of `Supjibi' and `Celebrate 2' were sampled every 4 weeks, starting with the beginning of short days. At flowering, all eight cultivars were measured for diameter of the two largest bracts, number of bracts with burn, and plant height. Foliar P levels increased over the growing season for `Supjibi' with a reading of 0.9% at anthesis, but for `Celebrate 2', levels peaked 4 weeks before anthesis (0.8%). At triple superphosphate rates > 3.11 kgP/m3, plant height decreased, and there was a significant cultivar × treatment interaction for descreased bract diameter. The eight cultivars exhibited varying degrees of susceptibilities to bract-edge burn as the amount of P applied to the root medium increased, with `Dark Red Hegg', `V-14 Glory', and `Red Sails' having the highest burn incidence.
Postharvest Storage Quality of Gamma-irradiated `Climax' Rabbiteye Blueberries
Authors: Miller W.R. , Mitcham E.J. , McDonald R.E. , King J.R.
Published: February 2019

Postharvest quality of `Climax' rabbiteye blueberries (Vaccinium ashei Read) was evaluated after exposure to dosages of 0, 0.75, 1.5, 2.25, or 3.0 kGy gamma irradiation (0.118 kGy·min-1) and after subsequent storage. Irradiation did not affect weight loss, but irradiated berries were softer than nontreated berries. There was also a trend toward increased decay as dose increased. Irradiation had no effect on powdery bloom or surface color; total soluble solids concentration, acidity, and pH were affected slightly. Flavor preference was highest for nonirradiated berries and generally declined as dosage increased. Irradiation at 2.25 and 3.0 kGy resulted in increased levels of xylosyl residues in cell walls, and xylosyl residues were the most abundant cell-wall neutral sugar detected in blueberries. There was no evidence of cell wall pectin loss in irradiated berries. Irradiation at 21.5 kGy lowered the quality of fresh-market `Climax' blueberries.
Prunus Rootstock Affect Long-term Orchard Performance of `Redhaven' Peach on Brookston Clay Loam
Authors: Layne Richard E.C.
Published: February 2019

Performance of `Redhaven' peach [Prunus persica (L.) Batsch.] propagated on nine experimental Prunus rootstock was evaluated over 8 years beginning in 1984, in a randomized complete-block experiment with 10 replications on a Brookston clay loam soil type near Harrow, Ont. This experiment was part of an interregional NC-140 peach rootstock experiment. Significant rootstock-induced effects were noted for increase in trunk cross-sectional area, cumulative tree height and spread, cumulative number of root suckers, yield, average fruit weight, yield efficiency, winter injury, cold hardiness, and tree survival. None of the clonally propagated rootstock gave satisfactory overall performance. All trees on GF655-2, 80% on GF677, 60% Self-rooted, and 50% on GF1869 were dead by the eighth year. In addition, suckering was a major problem on GF1869 and a moderate problem on GF655-2. `Citation' induced the most scion dwarfing but had the lowest yields and low yield efficiency. When yield, yield efficiency, fruit size, and tree mortality were considered together, the four peach seedling rootstock performed better than the other Prunus rootstocks and were ranked as follows: Siberian C, Halford, Bailey, and Lovell. Of these, the first three could be recommended with the most confidence to commercial growers who grow peaches on fine-textured soils in northern regions.
Heritability Estimates of Turf-type Characteristics in Buffalograss
Authors: Browning S.J. , Riordan T.P. , Johnson R.K. , Johnson-Cicalese J.
Published: February 2019

Buffalograss [Buchloë dactyloides (Nutt.) Engelm] is a drought-resistant, dioecious species, native to the Central Great Plains, which shows excellent potential as a low-maintenance turfgrass. Although buffalograss can be propagated vegetatively, there is a need for seeded turf-type cultivars. To assist in developing seeded cultivars, heritabilities of turf characteristics were estimated. Heritabilities from maternal half-sib analyses ranged from h2 = 0.04 ± 0.03 for the 1988 uniformity rating to h2 = 0.62 ± 0.26 for the 1989 spring color rating. Heritability estimates calculated from offspring-parent regression were also variable and generally lower than maternal half-sib analysis. The results suggest that some turf characteristics are highly heritable and that growing conditions markedly affect heritability estimates.
A BIOECONOMIC MODEL OF MELON PRODUCTION FOR MULCH AND ROWCOVER MANAGEMENT
Authors: Jenni Sylvie , Stewart Katrine A.
Published: February 2019

Quebec vegetable growers are increasingly using agricultural plastics (plasticulture) not only for gains in crop yield, earliness, and quality, but also for weed control and water and fertilizer conservation. Curcubitaceae include heat-loving crops that respond well to plasticulture. Melons are among the most responsive of all crops because they are sensitive to both low soil and air temperatures and to wind, but are very tolerant of high temperatures. The objective of this project was to develop a bioeconomic model that will predict the yield and timing of a melon crop under a number of mulch/tunnel combinations, evaluate the profitability of each production regime, and establish the optimal combinations that will maximize profit and continuity of supply over an extended growing season. A compartment model representing state, rate, and driving variables will be presented.
USE OF A “LATE WATER” FLOOD FOR PEST CONTROL IN CRANBERRY PRODUCTION: IMPACT ON PEST POPULATIONS, PLANT GROWTH, AND PRODUCTIVITY
Authors: DeMoranville Carolyn , Averill Anne , Averill Martha
Published: February 2019

In commercial cranberry (Vaccinium macrocarpon Ait.) production, flooding is used as a cultural practice for harvest and for winter protection. In addition, after the withdrawal of the winter flood, cranberry bogs may be reflooded in the spring, a practice known as holding “late water” (LW). This practice was used by early cranberry growers in Massachusetts to avoid spring frost and to promote keeping quality in the harvested fruit. Recently, LW has been “rediscovered” as a cultural tool with the potential for reducing inputs of chemical pesticides and fertilizers. We have begun to document the effects of LW on pest populations and on cranberry plants to provide growers with a solid basis for deciding whether to use this cultural practice. In 1993, 11 LW bogs were studied and compared to control bogs. All of the bogs showed acceptable levels of insect and disease damage on the fruit at harvest. The average number of pesticide applications for the LW bogs vs. controls was 0.9 vs. 2.6 for insecticides and 1.3 vs. 2.8 for fungicides.
PLASTICULTURE RESEARCH AND DEVELOPMENT IN QUEBEC REGION
Authors: Bégin Serge , Calandriello Joe , Dubé Pierre A.
Published: February 2019

In Québec the intensive use of plastic films in field production of vegetables and fruit is evident by increased acreage for this sector of agriculture since 1985. This technique is used particularly for sweet corn, cucurbitaceae and solanaceae, and strawberry production. Since 1987 some research projects have been established by the research and development division of the Quebec ministry of agriculture (MAPAQ) to adapt this technology to the Québec climate and to the needs of producers. The objectives of MAPAQ researchers are to extend the production season, improve the quality and productivity of fruit and vegetable crops, diminish production costs, and propose profitable alternatives for controlling crop pests.
ELECTROPORATION-MEDIATED GENE TRANSFER TO PROTOPLASTS OF ASPARAGUS OFFICINALIS L.
Authors: Mukhopadhyay Sandip , Desjardins Yves
Published: February 2019

Transient expression of electroporation-mediated DNA uptake was monitored in callus-derived protoplasts of two asparagus (Asparagus offcinalis L.) genotypes by measuring the GUS activity. The level of expression and the viability of the protoplasts were influenced by the voltage and duration of the electric pulse. An increased plasmid DNA concentration and the presence of polyethylene glycol (PEG) in the electroporation medium enhanced the transient expression level. A considerable increase in GUS activity was observed in the presence of both PEG and heat-shock treatments than with PEG treatment alone. An optimal level of GUS activity was obtained after electroporation with a capacitive discharge of 500 V/cm and 94 ms duration. The two genotypes differed in their responses in vitro and also showed variable levels of transient expression. The present technique was suitable to obtain transgenic plants, as histochemical GUS assay revealed GUS activity in the protoplast-derived microcolonies as well as in callus tissues.
Medium and Fertilizer Affect the Performance of Phalaenopsis Orchids during Two Flowering Cycles
Authors: Wang Yin-Tung , Gregg Lori L.
Published: February 2019

Bare-root seedling plants of a white-flowered Phalaenopsis hybrid [P. arnabilis (L.) Blume × P. Mount Kaala `Elegance'] were grown in five potting media under three fertility levels (0.25, 0.5, and 1.0 g·liter-1) from a 20N-8.6P-16.6K soluble fertilizer applied at every irrigation. The five media included 1) 1 perlite:1 Metro Mix 250:1 charcoal (by volume); 2)2 perlite:2 composted pine bark:1 vermiculite; 3) composted pine bark; 4) 3 perlite:3 Metro Mix 250:1 charcoal; and 5) 1 perlite:1 rockwool. During the first flowering season, plants in the 1 perlite: 1 Metro Mix 250:1 charcoal medium had slightly fewer but larger flowers and thicker stalks (section of the inflorescence between the base and oldest flower) than those in the 1 perlite:1 rockwool medium. Medium had no effect on stalk length. Two media (3 perlite: 3 Metro Mix 250: 1 charcoal and 1 perlite: 1 rockwool) resulted in root systems that were inferior to those in the others. Fertilizer level had no effect on bloom date or flower size. Regardless of medium, increasing the fertility from 0.25 to 1.0 g·liter-1 increased flower count, stalk diameter and length, and leaf production following flowering. During the second flowering season, media had limited effect on plant performance. Increased fertility promoted earlier inflorescence emergence and blooming. Higher fertilizer rates also caused a linear increase in the number of flowers and inflorescences per plant, and in stalk diameter, total leaf count, and leaf size.
PCIB Enhances Regeneration of Ipomoea cordatotriloba Dennstedt Leaf Explants and Protoplasts
Authors: Kobayashi Ruth S. , Bouwkamp John C. , Sinden Stephen L.
Published: February 2019

Leaf callus of Ipomoea cordatotriloba was initiated by culturing explants on Linsmaier and Skoog medium containing 3 g yeast extract/liter, 18.9 μm ABA, 2.3 μm 2,4-D, and 0.15 m sucrose. Calluses were transferred to Murashige and Skoog media containing 17.8 μm BA and 0, 1, 10, or 100 μm PCIB. The number of shoots from calluses grown on medium containing 10 μm PCIB increased significantly, and the percentage of calluses exhibiting shoot regeneration almost doubled compared to calluses grown on regeneration medium without PCIB. Protoplasts isolated from stem and petiole tissues of in vitro-grown plants were cultured in Kao and Michayluk 8p medium to the callus stage. Calluses (4-6 mm) were transferred to the callus induction and regeneration media used to regenerate leaf-explant callus. Of the protoplast-derived calluses cultured on media containing 10 or 100 μm PCIB, ≈13% and 18%, respectively, regenerated shoots after 2 months; none regenerated on the medium without PCIB. Chemical names used: abscisic acid (ABA); 2,4-dichlorophenoxyacetic acid (2,4-D); N6-benzyladenine (BA); α -p-chlorophenoxyisobutyric acid (PCIB).
011 RAPD ANALYSIS IDENTIFIES GENETIC VARIATION AND RELATEDNESS WITHIN THE CRANBERRY VARIETY MCFARLIN
Authors: Novy Richard , Vorsa Nicholi , Patten Kim
Published: February 2019

The cranberry cultivar `HcFarlin', selected from a natural bog in Massachusetts in 1874, has become the most widely grown cultivar in the Northwestern U.S.A. Washington state growers have noted variable productivity among `McFarlin' bogs. The determination of whether there is a genetic basis for the variability has been made difficult by a paucity of reliable morphological descriptors in cranberry. A random amplified polymorphic DNA (RAPD) analysis of 45 clones sampled from 12 WA `McFarlin' bogs identified 17 unique RAPD profiles. Cluster analysis identified 7 groups having various numbers of distinct, but related individuals. Eight clones were found to have RAPD profiles identical to the cultivar `Howes' indicating varietal misclassification had occurred in some bogs. One group of clones that originated from bogs classified as “Good” or “True” Mcfarlin' by growers had RAPD profiles similar to those of representatives from WI and MA `Mcfarlin' bogs. RAPD analysis has shown that `McFarlin' is represented by several genotypes, suggesting that the observed variability in production may have a genetic component.
013 YEAR-TO-YEAR CONSISTENCY OF HARVEST DATA FROM RED RASPBERRY BREEDING PLOTS
Authors: Moore Patrick P.
Published: February 2019

In our breeding program, harvest data is first collected two years after planting. In order to streamline efforts, some selections are discarded after the first harvest season and attention is concentrated on the remaining selections. Some selections that could become potentially superior cultivars that are slow to establish may be discarded. To test how reliable the first year data is for making decisions, the first year harvest data from five plantings was compared with the second year harvest data. Fruit rot and yield were the least consistent (r = 0.28 and 0.36 respectively) while fruit weight (r=0.76), fruit firmness (r=0.63) and midpoint of harvest (r=0.79) were more consistent. The impacts of decisions based on first year harvest data will be discussed.
015 PERFORMANCE OF TWELVE STRAWBERRY GENOTYPES IN FUMIGATED AND NONFUMIGATED SOIL
Authors: Larson Kirk D. , Shaw Douglas V.
Published: February 2019

Performance traits for twelve strawberry genotypes (Fragaria × ananassa) were evaluated in annual hill culture, with and without preplant soil fumigation (methyl bromide/ Chloropicrin 67:33, 350#/A) at two location. One trial followed several cycles of strawberry plantation whereas the other had not been planted to strawberries for over 20 years. Plant mortality was less than 3%. thus the main effects of fumigation treatment in these experiments must be due to sublethal effects of soil organisms. Plants grown in nonfumigated soil yielded 57% and 51% of the fruit produced by plants on adjacent fumigated soil, for “new” and “old” strawberry ground respectively. Highly significant (P<0.01) differences were also detected for fruit weight (88% and 93%) and leaf number after plantation establishment (73% and 80%). Significant genotype × fumigation interaction was not detected for any of the Performance traits. These results demonstrate that strawberry productivity is substantially increased by fumigation, even in the absence of lethal pathogens. More importantly, little opportunity exists for developing cultivars specifically adapted to nonfumigated soils.
021 RESPONSE OF BEGONIA AND CHRYSANTHEMUM TOPACLOBUTRAZOL RESIDUES ON SURFACES IN SUBIRRIGATION
Authors: Al-Badawy Ahmed A. , Barrett James E. , Nell Terril A.
Published: February 2019

To evaluate importance of paclobutrazol residues on surfaces, begonia (Begonia semperflorens) cv. Whisky and chrysanthemum (Dendranthema grandiflora) cv. Coral Davis plants were grown in flats sprayed with paclobutrazol at 0, 50, 100, 200 and 400 ppm.

For begonia, the plant heights at 2 and 4 weeks after treatments were decreased by 39 to 49% and by 55-69%, respectively. The overall change in height ranged from 2.1 to 4.9 cm compared to 15.3 cm for the control plants.

For chrysanthemum, a reduction in plant height was observed and the overall change in height ranged from 2.9 to 5.6 cm compared to 28.8 cm for the control plants.

Based on these results, there is a potential for paclobutrazol to affect non-target plants when subirrigation is used.
024 ETHYLENE EFFECTS ON MINIATURE POTTED ROSES
Authors: Edwards Thea M , Nell Terril A. , Barrett James E.
Published: February 2019

Increased rates of senescence and ethylene related damage of potted flowering plants have been observed in supermarket produce areas where flowers and climacteric produce are displayed together. Ethylene levels in produce areas were found to average 20 ppb. An open system of clear glass chambers with fiberglass lids was designed to simulate retail supermarket conditions. The chambers were kept in postharvest rooms where light level and temperature could be controlled. In a 3 by 3 by 3 Box-Behnken design, Sunblaze `Candy' miniature potted roses were exposed to three levels of ethylene, 20, 40, and 80 ppb, for 1, 2, and 4 days. The three light levels used were: 0, 7, and 14 μmol·m-2·s-1. Ethylene damage was based on leaf and bud drop and decreased flower longevity.
028 SOMATIC EMBRYOGENESIS IN QUERCUS SPECIES
Authors: Vyapari Sudeep , Khatamian Houchang
Published: February 2019

Somatic embryogenesis was successfully achieved in chinkapin oak (Quercus muehlenbergii Engelm.) and pin oak (Quercus palustris Muenchh.) when surface disinfested zygotic embryo explants were cultured on MS or WPM containing BA or kinetin (1.0 or 2.0 mg 1-1) plus IBA (1.0 mg 1-1). Immature embryos resulted in greater callus induction than the mature ones. Two weeks of dark, proved to be superior to 4 weeks or no dark in callus induction. Somatic embryos of pin oak distinctly showed globular, heart and cotyledonary stages.

Maturation and germination of pin oak somatic embryos was done in growth regulator free WPM by increasing levels of agar (7 - 15 g 1-1). Somatic embryos cultured at various levels of agar were then maintained in incubator under standard conditions, desiccated by air-drying or subjected to chilling temperature for 4 weeks to enhance germination of somatic embryos. Root or shoot formation was observed in some cultures, and medium with 9 g 1-1 agar induced plantlet production in 7% of the cultures.
029 COMPARISON OF ADVENTITIOUS REGENERATION SCHEMES IN WHITE ASH
Authors: Bates Sharon A. , Preece John E. , Yopp John H.
Published: February 2019

White ash has been adventitiously regenerated via organogenesis, somatic embryogenesis, and nodule culture. Explant source genotype, plant growth regulator type and concentration affected the type and/or frequency of regeneration observed. Organogenesis was obtained only when thidiazuron was added to the medium and nodules formed only in liquid culture after exposure to BA. Somatic embryos formed when explants were exposed to 2,4-D regardless of cytokinin used. Although large numbers of somatic embryos and nodules may be obtained through liquid suspension cultures, few plantlets were recovered compared to shoot organogenesis. Elongated adventitious shoots elongated and epicotyls from germinated somatic embryos rooted easily in vitro or under intermittent mist and were then acclimatized to the greenhouse and planted in the field.
035 Disease reactions of apple genotypes to several bitter rot pathogens
Authors: Shi Y. , Rom C. , Correll J.C.
Published: February 2019

Disease reactions of 11 apple genotypes (Braeburn, Empire, Gala, Granny Smith, Golden Delicious, Jonathan, Jonagold, MacIntosh, Red Delicious, Red Rome and Spartan) to 3 genetically distinct bitter rot pathogens (Colletotrichum gloeosporioides [teleomorph (T) and nonteleomorph (NT)] and C. acutatum) were examined. Fruit were surface sterilized, and then inoculated either by placing a 100 ul spore suspension (2×104 spores/ml) into wounds or spraying the inoculum onto unwounded fruit. Inoculated fruit were incubated at 26C and 100% RH. Disease reactions were quantified by measuring lesion diameter and depth in wounded fruit, or counting the number of lesions on unwounded fruit. There was a significant interaction between apple genotypes and all 3 pathogenic isolates. The T isolate was the most virulent on all genotypes. In general, cultivars with the smallest lesions in the wound test had the fewest lesions in the unwounded test. Lesion number and size were significantly lower on Granny Smith, Jonagold, Jonathan, Red Delicious and Red Rome. Of the genotypes tested, Braeburn, Gala and MacIntosh apparently were the most susceptible.
039 INTERSTOCK PRESERVATION OF PLANT GERMPLASM
Authors: Nee Chenq-chu
Published: February 2019

The purpose of this invention is to preserve the germplasm which are compatibly graftable for each other in the specific environment. The preserved [interstock] is protected by the rootstock which is used to the stresses from underground, and the “topstock” which is tolerant to the stresses from aboveground.

The compound plant (Top-interstock-rootstock) is different from the traditional combinations which the interstock impove the impatibility between scion and rootstock. The interstock in this design must be compatible with its top and rootstock parts and keep “paradormancy” in the germplasm repository.

Preservation of pear species & cultivars will be presented to describe the details of the techinque.
046 COMPARATIVE GROWTH RESPONSES AND COSTS UTILIZING TRADITIONAL AND AUTOMATED TISSUE CULTURE SYSTEMS
Authors: Tisserat Brent
Published: February 2019

Comparative tests were conducted to determine the influence of the culture vessel size and medium volume on the growth rates of shoot tips of peas (Pisum sativum cv. `Wando'), lettuce (Lactuca salvia) Kidney beans (Phaseolus vulgaris). Culture vessels employed included: culture tubes, baby food jars, Magenta rectangular containers, 1 -pint Mason jars, 1 -quart Mason jars, l-quart Mason jars employed with an automated plant culture system (APCS), 1/2-gallon Mason jars with an APCS, BioSafe containers with an APCS, and mega-culture chambers with an APCS. The APCS consisted of a peristaltic pump, media reservoir containing 1 liter of nutrient medium, and a culture chamber (<925 mm3). High positive correlations occurred comparing culture weight, leaf length and plant height with culture chamber volume, media volume and culture chamber height. APCSs consistently gave higher growth rates and exhibition of mature morphogenetic responses such as flowering and fruiting than growing plants on agar culture systems. Cost analysis comparing APCSs and conventional tissue culture systems is presented.
048 FERTILITY RESTORATION OF AN INTERSPECIFIC ALSTROEMERIA HYBRID BY GENETIC MANIPULATIONS IN VITRO
Authors: Lu Chunsheng , Bridgen Mark
Published: February 2019

An interspecific hybrid of Alstroemeria aurea × Alstroemeria caryophyllaea was rescued by immature ovule culture and was completely sterile. To restore the fertility of the hybrid, young, vigorous shoots and buds were treated aseptically with three colchicine levels (0.2, 0.4, and 0.6% in DMSO solution) at four treatment durations (6, 12, 18, and 24 hours), before being cultured onto a shoot regeneration medium for regrowth and development. The growth and development of all treated shoots were retarded by the colchicine. New shoots were regenerated from 61% of the surviving cultures after one month. The degree of recovery was not significantly different among treatments, although the highest concentration (0.6%) and the longest time treatment (24 hours) resulted in some morphological abnormalities. Cultures with newly regenerated shoots/buds were able to initiate roots and, eventually, sixty plantlets were transplanted into the greenhouse after acclimatization. Cytological examination of the root tip cells of the plantlets indicated that tetraploids (2n=4x=32) as well as aneuploids plants were generated from the colchicine treatment, whereas all plants from the control were diploids (2n=2x=16). Details explaining cytological changes and the fertility of the colchiploids will be presented.
057 IN VITRO SCREENING OF WESTERN UNITED STATES VACCINIUM SPECIES FOR pH TOLERANCE
Authors: Moberg Amy J. , Luby James J. , Rosen Carl J. , Ascher Peter D.
Published: February 2019

Accessions of Vaccinium species (deliciosum, ovalifolium, membranaceum, parvifolium, scoparium) were evaluated for tolerance to higher pH in the root zone using an in vitro screening procedure. Seeds were germinated on media containing all essential nutrients with nitrogen in the nitrate form at pH 5 and pH 6 and evaluated for 21 weeks. Excess EDTA was used to buffer the micronutrients and pH was buffered by MES and succinic acid. Germination varied among species with V. ovalifolium being highest and V. parvifolium not germinating at all. Mortality was lower at pH 5. At pH 6, V. ovalifolium and V. membranaceum exhibited variation for growth while all other species suffered complete mortality.
088 INFLUENCE OF ROOTSTOCK AND VINE SPACING ON THE CONCENTRATION OF MINERALS IN PETIOLES AND FRUITS OF CABERNET SAUVIGNON GRAPEVINES GROWN IN NAPA VALLEY
Authors: Kliewer W. Mark , Benz Jason
Published: February 2019

The effects of 7 rootstocks (AxR#1, 110R. 5C, 3309, 420A, 1616 and 039-16) grafted to Cabernet Sauvignon (clone #8) in combination with 3 between row spacings (2, 3, and 4 m) and 2 in-row spacings (1 and 2 m) on the level of minerals in petioles sampled at full bloom and at veraison on the mineral composition of fruits at harvest were evaluated over a 3 year period (1991 to 1993) in a replicated field plot established at Oakville in 1987. 039-16 petioles had the highest level of K, Ca and NO3, whereas 420A had the lowest concentration of these minerals, the other 5 stocks being intermediate. Petiole Mg level was highest in 420A and lowest in 039-16. 039-16 fruits at harvest had the highest level of K, malate, and pH, whereas 420A fruits were lowest in these substances. Between row spacing showed no significant effects on the concentration of minerals in leaves and fruits. However, leaves from vines spaced 1 m apart within rows had lower levels of Ca and Mg than 2 m vine spacing. One m vine spaced fruits were lower in °Brix hut higher in titratable acidity and malate than 2 m vine spaced fruits. Regression analysis showed that the number of roots per unit volume of soil was positively related to the concentration of K in leaves and fruits, regardless of the rootstock used.
101 EVALUATION OF PLANT WATER USE AND CROP TEMPERATURE OF NEW GUINEA IMPATIENS (IMPATIENS X HB.) UNDER INFRARED HEATING
Authors: Al-Faraj Abdulelah , Meyer George , Fitzgerald Jay B.
Published: February 2019

A plant-based temperature control system for infrared heating to maintain the plant canopy at a desired temperature was evaluated under growth chamber conditions with possible projections to greenhouse environment. Benefits for using this system includes energy saving and plant protection. Infrared radiant heaters raised canopy temperatures to the optimum range which increased water use of New Guinea Impatiens over the same kind of plants grown with no radiant heat. Plant water use was 118% higher at an 18°C air temperature vs. 8°C air temperature and 33% higher at 24°C air temperature vs. 18°C air temperature. The degree of increase in plant water use was proportional to decrease (leaf air) temperature. The Penman-Monteith equation gave satisfactory results when the differential between leaf and air temperature was very low. At high (leaf-air) temperature deviation, the latent heat equation used to estimate stomatal resistance gave higher values for heated plants.
115 EFFECT OF NITROGEN SOURCE AND LEVEL ON VEGETABLE AMARANTH
Authors: Makus D. J.
Published: February 2019

On 3 Aug. 1993, 20-day-old `Hinn Choy' plants (Amaranthus tricolor L.) were-planted on 15 × 15 cm spacings in 4-row beds at 1.3 m row spacings in a Leadvale silt loam soil. Nitrogen sources of NH4, NO3 and NH4 NO3 were used at rates of 0, 100 and 200 kg/ha, and were split-applied at and 1 week after transplanting. All treatments received both supplemental K and P at the rate of 90 kg/ha at planting. Plants were harvested 31 days after transplanting. Plants given the NH, source were taller, and were higher in yield, leaf chlorophyll, total carotenoids and Mn (dry wt basis) than were plants given other N-sources. NO3-N fertilizer increased leaf Fe and Cu, and residual soil K and NO3, but reduced Mn levels. Leaf blade Ca was highest when NH4NO3 fertilizer was used. Increasing N-rates decreased both soil pH linearly and leaf blade Ca but linearly increased soil EC, NO3, and S and leaf blade N, K, S, P, NO3, Fe, chlorophyll and carotenoids.
118 ACTUAL AND SIMULATED MITE-FEEDING EFFECTS ON TART CHERRY PHOTOSYNTHESIS IN THE FIELD
Authors: Hubbard Mark A. , Flore James A. , Wise John C. , Johnson James W.
Published: February 2019

European red mite (Panonychus ulmi) populations were monitored in a tart cherry (Prunus cerasus `Montmorency') orchard and the effects on photosynthesis determined. Mites levels were controlled in some trees by miticide applications to establish different cumulative mite*days in the trees. Photosynthetic inhibition caused by insect injury was also simulated by spraying other trees with 78 ppm Terbacil at one of four different times during the season, The mite*days accumulated in 1993 ranged from 937 to 2205, however, there were no differences in single leaf or whole tree CO2 assimilation, chlorophyll a fluorescence, or chlorophyll levels among the different levels of mite damage. Likewise, there were no differences in these same parameters among the Terbacil-treated trees except that photosynthesis was reduced on treated trees for 10-14 days, after which photosynthesis recovered to the level of the controls. There were no differences in yield or fruit quality among any treatments, and cold hardiness and return fruiting characteristics will be measured.
137 POSTHARVEST DELAY OF MUSKMELON FRUIT MEMBRANE SENESCENCE BY CALCIUM
Authors: Lester Gene
Published: February 2019

Hypodermal mesocarp disks from abscised muskmelon fruits (Cucumis melo L. var. reticulatus Naud.) were floated in 0.00, 0.04 or 0.16 M CaCl2 plus 0.35 M mannitol at ′20C in the dark for 10 days. Changes in chlorophyll, protein and total phospholipids all indicators of membrane senescence were assayed. The catabolism, percent retention, of chlorophyll, protein and total phospholipids was delayed by 0.04 M Ca, but accelerated by 0.16 M compared to no Ca. Loss of membrane integridity, increased free sterol: total phospholipid (umol./umol.), was delayed by 0.04 M Ca, hut accelerated by 0.16 M compared to no Ca. The degree of lipid saturation was inconclusive between Ca treatments. Muskmelon fruit disks membrane lipid degradation is slowed by 0.04 M Ca but accelerated by supraoptimal 0.16 M Ca treatment.