bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spotless Gold, Spotless Yellow, and Spotless Pink Rose: Blackspot Resistant Breeding Lines1
Authors: Semeniuk Peter 
Published: September 2022

Abstract
Here we report the first evidence of resistance of roses to the blackspot disease, Diplocarpon rosae Wolf. Black-spot is a major foliar disease of roses that causes severe losses to commercial and home gardeners. It spreads rapidly on susceptible cultivars, results in premature defoliation, and severely reduces yield and quality of this popular plant. Growers must make frequent applications of fungicides which are costly in labor and materials and environmentally undesirable. Stewart and Semeniuk (3) reported on the problems and techniques in transferring resistance to blackspot from the diploid species to garden roses (1, 2). The breeding lines Spotless Gold, Spotless Yellow, and Spotless Pink will be released for use as resistant parents in breeding programs. This germplasm should be valuable to breeders for its resistance to 7 isolates of D. rosae from Belts-ville, Maryland, Tifton, Georgia, Ames, Iowa, Ithaca, New York, Delaware, Ohio, University Park, Pennsylvania, and Tyler, Texas. These roses have been released by the U.S. Department of Agriculture, Science and Education Administration. The developmental work was done by the Florist and Nursery Crops Laboratory at the Agricultural Research Center, Beltsville, Maryland.
Lettuce Emergence from Vermiculite Seed Tablets Containing Activated Carbon and Phosphorus1
Authors: Sharpies G. C. , Gentry J. P. 
Published: September 2022

Abstract
Lettuce (Lactuca sativa L.) seedlings emerged from vermiculite tablets but did not survive in warm weather plantings (maximum daytime air temperature >32°C) under irrigated desert conditions. Final plant stands of 90% were obtained with modified seed tablets containing activated carbon and nutrient P in cool weather (maximum daytime air temperature <26°C).
Retention of Fruit Firmness and Increase in Vegetative Growth and Fruit Set of Apples with Aminoethoxyvinylglycine1
Authors: Williams Max W. 
Published: September 2022

Abstract
Aminoethoxyvinylglycine (AVG), an inhibitor of ethylene synthesis, applied to ‘Delicious’ apple trees (Malus domestica Borkh.) 2 weeks before harvest reduces loss of flesh firmness of apples in storage and increases vegetative growth in the following growth season. When applied to ‘Delicious’ or ‘Golden Delicious’ trees after full bloom, the “June drop” was completely eliminated; thus, fruit set was significantly increased.
Nitrogen Fertilization Increases Yield without Enhancing Blossom Receptivity in Almond1
Authors: Weinbaum S. A. , Uriu K. , Micke W. C. , Meith H. C. 
Published: September 2022

Abstract
Ground application of urea increased yields of ‘Nonpareil’ almond (Prunus amygdalus Batsch) by increasing the number of flowers per tree rather than by increasing blossom receptivity and percentage fruit-set. Hand pollination of flowers on caged limbs indicated that blossom receptivity declined between 3 and 6 days after anthesis.
Micropropagation of Rabbiteye Blueberries1
Authors: Lyrene P. M. 
Published: September 2022

Abstract
Multiple shoot formation from shoot tips taken from juvenile rabbiteye blueberry (Vaccinium ashei Reade) seedlings was induced on Knops medium with agar, casein hydrolysate, and N6-(∆2-isopenteny1)-adenine (2iP) at 15 mg/liter. These shoots could be easily subcultured and rooted readily when cut off and inserted into a peat-perlite mixture under mist in the greenhouse. Nonjuvenile shoot tips from rabbiteye cultivars were difficult to establish in cultures. Successful establishment of some clones occurred by formation of fine, filamentous shoots which were as amenable to subculture as juvenile shoots. A 50-fold multiplication rate every 4 months was obtained with some clones.
Symptoms of Acetaldehyde Injury on Head Lettuce1
Authors: Stewart Joseph K. , Aharoni Yair , Hartsell Preston L. , Young David K. 
Published: September 2022

Abstract
Acetaldehyde (Aa), a volatile produced in small quantities by plants, is a potential fumigant for killing the green peach aphid, Myzus periscae (Sulzer), on harvested head lettuce, (Lactuca sativa L. var. capitata). Concentrations of 3.0 to 6.0% Aa killed 100% of the green peach aphids on harvested head lettuce, but induced dark-green, water-soaked, necrotic areas on the outer leaves of the heads and occasionally caused a type of injury, similar to russet spotting, which we call tan flecking. Concentrations of 1.5 to 2.0% Aa, which killed all of the aphids, did not injure the lettuce.
Ion-selective Electrode Determination of Calcium in Apple Fruits1
Authors: Himelrick David G. , Ingle Morris 
Published: September 2022

Abstract
A rapid method for estimating total Ca of apple (Malus domestica Borkh.) peel and flesh was developed using a Ca-selective electrode to measure ionic juice Ca++. Ionic juice Ca++ ranged from 3.2 to 7.2 ppm. Significant correlations were found between total Ca and ionic juice Ca++ for flesh (r = 0.91) and peel (r = 0.87).
The Effect of Drastic Reduction of Water Input on Mature Walnut Trees1
Authors: Martin G. C. , Uriu K. , Nishijima C. 
Published: September 2022

Abstract
Withholding irrigation of walnut trees (Juglans regia L. cv. Ashley) for one growing season significantly reduced trunk growth and kernel weight. Tree survival and return cropping were unaffected. When irrigation was resumed kernel weight was significantly heavier than that from trees irrigated the previous year.
Colorado Horticulture
Authors: Knutson Kenneth W. 
Published: September 2022

Abstract
Horticulture in Colorado is diverse from the standpoint of types of plants grown and even more so in terms of climate. Topographic elevation ranges from slightly over 3000 feet in the eastern high plains to over 14,000 feet in the Rocky Mountains (50 peaks exceed this elevation!). The frost-free growing season varies from 16 days in certain high mountain valleys to 192 days in the fruit growing areas in western Colorado. However, a common factor in all areas, regardless of altitude, is the need for irrigation water — Colorado is a semi-arid state in which precipitation varies from less than 8 to slightly over 16 inches.
Modification of Plant Architecture and Crop Yield by Breeding1
Authors: Coyne Dermot P. 
Published: September 2022

Abstract
Plant breeders have modified plant architecture to fit crop production systems, particularly for mechanical harvesting, but have given inadequate attention to the effects of architecture on yield. The development of high yielding dwarf wheat, rice and determinate tomato cultivars have emphasized the relation of plant architecture to crop yield. Delayed flowering of photoperiod sensitive dry beans (Phaseolus vulgaris L.) under long days produced more fruiting nodes per plant and increased yield 50 to 70%. The contributions of plant architecture components to yield and quality have been investigated with near-isogenic lines of various crops. Modifications of plant architecture have been adopted to alleviate heat and moisture stress, to confer insect resistance, and to avoid disease.
Induction of Staminate Flowers on Gynoecious Cucumber by Aminoethoxyvinylglycine1
Authors: Owens K. W. , Tolla G. E. , Peterson C. E. 
Published: September 2022

Abstract
Aminoethoxyvinylglycine (AVG) at 50,100, and 200 ppm induced staminate flowers on 3 gynoecious cucumber lines in the greenhouse. Both the time of application and the type of water used to prepare the AVG solutions had a significant effect on the node at which conversion from pistillate to staminate first occurred and on the total number of nodes bearing staminate flowers. Plants treated with 100 and 200 ppm AVG were chlorotic for about 10 days after application.
Ethephon as Harvest-aid for Muscadine Grapes1
Authors: Phatak S. C. , Austin M. E. , Mason J. S. 
Published: September 2022

Abstract
(2-Chloroethyl)phosphonic acid (ethephon) was applied at 0, 570, 1000 and 2000 ppm to muscadine grapes (Vitis rotundifolia Mich. cv. Hunt), 1, 2, or 3 days before once-over harvest. All ethephon treatments increased berry abscission and reduced skin tear due to harvest when berries were harvested 2 days or 3 days after spraying. Delaying harvest to 3 days after treatment with 2000 ppm ethephon increased berry abscission to 46% and reduced skin tear to 9% in 1977. In 1978, 2000 ppm of ethephon increased berry abscission to 29% and reduced skin rupture to 29%. Taste panels could not detect flavor difference from the ethephon treatments.
Breeding Strawberries for Resistance to the Aphids Chaetosiphon fragaefolii and C. thomasi1
Authors: Barritt Bruce H. , Shanks Carl H. 
Published: September 2022

Abstract
Segregation for resistance to the strawberry aphids, Chaetosiphon fragaefolii (Cockerell) and C. thomasi (Hille Ris Lambers), occurred in the first backcross from the resistant ‘Del Norte’ clone of Fragaria chiloensis (L.). Aphid populations on ‘Del Norte’ were 4 and 7% of those found on the susceptible cultivar ‘Totem’ in greenhouse and field evaluations respectively. Resistance of the most resistant backcross seedlings was comparable to that of the F1 parent but slightly less than ‘Del Norte’. Greenhouse and field evaluations gave generally similar results although field evaluations have greater practical significance.
Legume Cover Crops, Organic Mulch and Associated Soil Conditions, and Plant Nutrient Content for Establishing Quillou Coffee1
Authors: Oladokun Michael A. O. 
Published: September 2022

Abstract
Four cover crops, calopogonium (Calopogonium mucunoides Desv.), centrosema (Centrosema pubescens Benth.), pueraria (Pueraria phaseoloides (Roxb.) Benth.) and cowpea, (Vigna unguiculata Walp) and 2 types of organic mulch, grass and banana/plantain leaves were used in comparison with clean weeding as control in establishing Quillou coffee (Coffea canephora Pierre var canephora Haarer). Shade significantly affected the plant N, P, and K percent nutrient content but nonsignificant on Mg, Ca, and Na. Cover crop and mulch treatment effects were significant only with P and K while interactions between shade and these treatments were nonsignificant for any of the nutrients considered. Percent soil moisture content was influenced by both shade and treatments as well as their interactions in both June and January. Soil pH was significantly affected by both shade and other treatments in January but no significance was recorded in June.
Quality and Yield of ‘Keauhou’ Macadamia Nuts from Mixed and Pure Block Plantings1
Authors: Ito P. J. , Hamilton R. A. 
Published: September 2022

Abstract
Annual yields of ‘Keauhou’ macadamia (Macadamia integrifolia Maiden & Betche) from a mixed planting averaged about 16 kg per tree more than from a pure block planting. The nuts from mixed-orchard nuts as compared to pure block stands were large (2.72 vs. 2.39 g), had more kernels (38 vs. 35%) and more oil (80.0 vs. 75.7% no. 1 nuts, those > 72% oil).
Use of Metal Compounds as Root Pruning Agents1
Authors: Pellett Harold , Litzow Margaret , Mainquist Laurie 
Published: September 2022

Abstract
Several metal salts were effective in killing root tips of squash, lima bean, and Kentucky coffeetree seedlings without damaging the rest of the plant in greenhouse trials. Silver nitrate was effective in promoting root branching of woody plant seedlings in a field trial.
Thatch Accumulation in Kentucky Bluegrass as Influenced by Cultivar, Mowing, and Nitrogen1
Authors: Shearman R. C. , Kinbacher E. J. , Riordan T. P. , Steinegger D. H. 
Published: September 2022

Abstract
Twenty-one Kentucky bluegrass (Poa pratensis L.) cultivais differed significantly in their thatching tendency during 4 years of study. ‘Glade’, ‘Cheri’, and ‘Victa’ accumulated the most thatch, while ‘S-21’, ‘A-34’, and ‘Park’ accumulated the least. Increasing mowing heights from 2.5 cm to 5.0 cm significantly increased the tendency to accumulate thatch. Increasing nitrogen nutritional levels from 10 g m−2 to 20 g m−2 did not increase thatching tendency.
Evaluation of Drip Irrigation for Container Production of Woody Landscape Plants1
Authors: Weatherspoon D. M. , Harrell C. C. 
Published: September 2022

Abstract
Average efficiency of drip systems (amount of water retained by container expressed as water supplied) over 2 years ranged from 44-72% as compared to 13-20% for overhead sprinklers. Chapin Leader Tubes and Micro-drippers and Spot System Vortex Emitters performed better and required less maintenance than Chapin Twin-wall hose or DuPont Viaflo tubing.
Overwintering Container-grown Ornamentals under Thermo-blankets with and without Clear, White, or Black Polyethylene1
Authors: Gouin F. R. 
Published: September 2022

Abstract
Early spring flowering of Forsythia × intermedia Zab. (forsythia) and growth of Cydonia sinensis Thouin (Chinese quince) can be prevented by over-wintering container grown plants under microfoam thermo-blankets covered with black, white, or clear polyethylene (poly) spray painted in late winter and diluted white latex paint. Although covering microfoam with black poly may extend its useful life and suppress the growth of winter weeds, it appears damaging to X Cupressocyparis leylandii A. J. Jacks & Dallin. (Leyland cypress) and Prunus laurocerasus L. (cherry laurel). Ilex crenata Thunb. (Japanese holly), Viburnum rhytidophyllum Hemsl. (leathe leaf viburnum) and Euonymous alata Thunb. ‘Compacta’ (dwarf winged euony-mus) responded equally well to all treatments. Thermo-blankets protected the roots from minimum killing temperatures but highest maximum temperatures were measured under polyethylene foam and microfoam covered with clear or woven clear polyethylene.
Freezing Resistance of Perennial Turfgrasses1
Authors: Gusta L. V. , Butler J. D. , Rajashekar C. , Burke M. J. 
Published: September 2022

Abstract
The cold hardiness of 6 cool season grass genera was compared in mid-winter under controlled freezing conditions. Creeping bentgrasses (Agrostis palustris Huds.) tolerated the lowest temperatures whereas perennial ryegrasses (Lolium perenne L.) was the least hardy. Kentucky bluegrass (Poa pratensis L.) readily loses cold hardiness when exposed to warm conditions and did not reharden when exposed to cool temperatures. Appreciable hardiness in Kentucky bluegrass was induced by simulating drought conditions.
Effects of Excess Manganese Nutrition on the Growth of Easter Lily1
Authors: Holmes R. L. , Coorts G. D. 
Published: September 2022

Abstract
Six levels of Mn were applied in nutrient solution to ‘Ace’ and ‘Nellie White’ Easter lilies (Lilium longiflorum Thunb.) grown to anthesis. ‘Nellie White’ Mn tissue content was higher than ‘Ace’. Foliar symptoms of Mn toxicity did not appear at or below solution applications of 50 ppm Mn. High levels of Mn resulted in shorter plants, lower plant dry weight, leaf chlorosis and chlorotic mottling, and some leaf curling.
Factors Influencing the Culture and Propagation of Xerophytic Succulent Species1
Authors: Stefanis James P. , Langhans Robert W. 
Published: September 2022

Abstract
Media, nutrition, light and temperature studies were conducted with several species of Cactaceae and Crassulaceae to develop systems for propagating and growing succulents from seed or cuttings in the cool climates and low light irradiances found at northern latitudes. A peat-perlite (1:1 by volume) medium was suitable for rooting and growth. Nitrate nitrogen applied at the rate of 100 ppm with every watering appears optimal for various species at all stages of propagation and development. Most species grew equally well when grown at 10° or 17ºC night temperature. Acceptable germination percentages were obtained with an irradiance of 220 µE·m−2s−1 and a medium temperature of 24°C.
In Vitro Propagation of Anthurium andreanum Lind.1
Authors: Kunisaki J. T. 
Published: September 2022

Abstract
High yields of viable cultures of Anthurium andreanum were obtained with the use of small explants of vegetative buds and a long disinfestation soak. Explants were grown into plantlets in modified Murashige and Skoog medium supplemented with 15% coconut water (by volume). For clonal increase, best results were obtained when stem sections from asepti-cally grown plantlets were cultured in medium containing 6-benzylamino purine (BA) at 0.2 mg/liter. There was no further increase in number of shoots at higher BA concentrations but callus growth increased and shoots were stunted.
Association of Calcium in Chilling Injury Susceptibility of Stored Avocados1
Authors: Chaplin Grantley R. , Scott K. J. 
Published: September 2022

Abstract
Visible injury in chilled avocados (Persea americana Mill.) was observed first in the distal end of fruit. The proximal end remained apparently unaffected unless exposure to chilling temperature was prolonged. In contrast, the concentration of endogenous Ca of individual fruit was always highest in the proximal end and lowest in the distal end. Severity of visible injury in stored fruit was significantly reduced when Ca was applied to harvested fruit by vacuum infiltration of CaCI2·
‘Santa’, ‘Gem State’, and ‘Benewah’ Tomatoes1
Authors: Boe A. A. , Pelofske P. J. , Bakken T. J. 
Published: September 2022

Abstract
‘Santa’, ‘Gem State’, and ‘Benewah’ tomatoes {Ly copersicon esculentum Mill.) are 3 new “ultra early” cultivars. ‘Santa’ and ‘Benawah’ resemble the “Sub Arties” (1) whereas ‘Gem State’ is a dwarf patio type similar to ‘Pixie’.
Effects of Naphthaleneacetic Acid on Fruit Size, Quality, and Ripening of ‘Zahdi’ Datepalm1
Authors: Mohammed Shafaat , Shabana Hassan R. 
Published: September 2022

Abstract
Preharvest application of naphthaleneacetic acid (NAA) at 10, 20, 40, and 60 ppm concentrations to immature ‘Zahdi’ date palm (Phoenix dactylifera L.) fruit 15 to 16 weeks after pollination (late chimri stage) influenced fruit size, quality, and ripening. Compared with the controls, 40 and 60 ppm NAA treatments increased fruit size, weight, volume, pulp to seed ratio, and moisture content At 60 ppm fruit weight was increased by 39%. Total soluble solids were not altered significantly. Fruit ripening was delayed at least one month by 40 and 60 ppm.
Somatic Embryogenesis in Cell Cultures of Carica stipulata1
Authors: Litz Richard E. , Conover Robert A. 
Published: September 2022

Abstract
Somatic embryogenesis was induced in cell suspension cultures of callus derived from peduncle explants of Carica stipulata Badillo. The presence of activated charcoal stimulated embryogenesis particularly when BA and NAA were both in the growth medium. Plantlets derived from embryos have been successfully transferred to potting mixture.
Partial Organogenesis in Tissue Cultures of Averrhoa carambola1
Authors: Litz Richard E. , Conover Robert A. 
Published: September 2022

Abstract
Callus was initiated from seedling leaf explants and from leaves of recent vegetative flushes of mature Averrhoa carambola L. trees on solid Murashige and Skoog medium with added growth regulators. Seedling-derived callus demonstrated a strong dependence on the presence of exogenous cytokinin, 1-5 mg/liter 6(γ, γ-dimethylallylamino) purine (2iP) with 0.2 mg/liter 2,4-dichlorophenoxyacetic acid (2,4-D), for induction and growth. Shoot differentiation was stimulated from seedling callus by increasing the concentration of available cytokinin. Callus induction and growth from young leaves of mature trees was auxin-dependent (2-5 mg/liter 2,4-D with 0.5 mg/liter 2iP. Organogenesis from callus cultures of mature leaf origin was not obtained.
In Vitro Propagation of Hosta sieboldiana1
Authors: Meyer Martin M. 
Published: September 2022

Abstract
Plants were initiated from florets of Hosta sieboldiana (Lodd.) Engler cultivars cultured on a modified Murashige-Skoog medium containing 0.5 – 2.5 mg/liter naphthaleneacetic acid (NAA) and 0.5 – 2.5 mg/liter 6-benzylamino purine (BA) and grown in the light. These plants could be separated and proliferated on a similar medium to give large numbers of plants. Plant propagated from ‘Frances Williams’ had a chimeral separation into green and gold sports as well as retaining the chimeral organization.
Influence of Fertilizer and Lime Rates on Nutrient Concentration in Highbush Blueberry Fruit1
Authors: Cummings George A. , Lilly J. P. 
Published: September 2022

Abstract
Concentrations of N, P, K, Ca, Mg, Mn, Fe, Zn and Cu in blueberry fruit (Vaccinium corymbosum L. cv. Wolcott) as influenced by 3 rates of N, P, and K and 2 rates of lime were determined for 2-4 years. Concentration varied among years, but the variation was much less for N, P, K, and Ca than for Mg and the micronutrients. Application of N, P, or K increased the concentration of the element applied. Application of lime did not influence elemental concentrations. Increasing N rates decreased fruit Ca, and P decreased Mn concentrations each year.
Effect of Silver Thiosulfate and Preservative Solutions on the Vase Life of Miniature Carnations1
Authors: Reid Michael S. , Farnham Delbert S. , McEnroe Ellen P. 
Published: September 2022

Abstract
Short-term or over-night pretreatment with solutions of a silver thiosulfate complex extended the vase life of fresh or stored miniature carnations (Dianthus caryophyllus L.) as much as the continuous use of commercial vase preservatives. Combining the 2 treatments further extended the vase life to 4 times that of control flowers. The time to wilting of the first flower was closely correlated with the mean vase life of all the flowers in a spray.
The Effect of Cumulative Photosynthetically Active Radiation on the Growth and Flowering of the Seedling Geranium, Pelargonium × hortorum Bailey1
Authors: Lee Erickson Virginia , Armitage A. , Carlson W. H. , Miranda R. M. 
Published: September 2022

Abstract
Growth and flowering of Pelargonium × hortorum Bailey cvs. Sprinter Scarlet, Sprinter White, and Ringo were associated with cumulative photosynthetically active radiation (PAR); 41-65% of the variability in days to flower was attributed to cumulative PAR. Vegetative and total plant height decreased as cumulative PAR increased. The number of lateral breaks increased as irradiance increased while fresh weight showed no consistent pattern.
Synthetic Pyrethroid Insecticides, Resmethrin and Permethrin, for Tropical Foliage Plant Protection1
Authors: Hamlen R. A. , Henley R. W. 
Published: September 2022

Abstract
Applications of resmethrin at 0.6 g/liter and permethrin at 0.3 g/liter concentrations did not satisfactorily control green peach aphid, Myzus persicae (Sulzer). One application of permethrin at 0.15 g/liter controlled thrips, Echinothrips americanus Morgan, but repeated applications of resmethrin were necessary. Only Brassaia actinophylla Endl. showed significant phytotoxicity to resmethrin, but permethrin caused excessive injury to B. actinophylla, Epipremnum aureum (Linden & Andre) Bunt., Maranta leuconeura E. Morr. and Nephrolepis exaltata (L.) Schott.
Ammonium Nitrogen Accumulation and Leaching from an All Pine Bark Medium1
Authors: Thomas Steve , Perry Fred B. 
Published: September 2022

Abstract
When a 200 ppm N solution as (NH4)2SO4 was percolated through a wet pine bark medium, 6 times the medium volume of the N solution was required to reach an equilibrium of N in the bark. Once equilibrium was reached, the water added, leaching of the ammonium ion was rapid. When twice the medium volume of water was passed through the medium, 85% of the ammonium ions were leached. After analysis of the leachate indicated no N being leached from the bark, 60 ppm of N remained in the bark.
‘Galaxy’ Magnolia1
Authors: Santamour Frank S. 
Published: September 2022

Abstract
Magnolia (liliflora ‘Nigra’ × sprengeri ‘Diva’) ‘Galaxy’, Accession No. 28352-14 and PI 433306, is a new introduction from the U.S. National Arboretum as part of its continuing program to develop new and improved cultivars of important landscape trees and shrubs. It is an upright, single-stemmed deciduous tree with strong branches and a pyramidal habit (Fig. 1). The large red-purple flowers are borne in profusion and open sufficiently late in the spring to avoid any significant frost damage.