bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for Evaluating Chemical Inhibitors of Apple Abscission
Authors: Marini Richard , Byers Ross
Published: September 2022

Several methods were evaluated for inducing apple (Malus domestica Borkh.) fruit abscission before the harvest season. Pedicels abscised within 7 days after being defruited, but drop inhibitors retarded abscission minimally. Injecting ethephon into the seed cavity induced only 70% to 80% fruit drop within 13 days after treatment. Removing the calyx half of a fruit (half-fruit) induced abscission within 13 days of treatment, and half-fruit responded to drop inhibitors. Scoring branches before treatment did not influence abscission of half-fruit, but increased the severity of phytotoxic symptoms caused by triclopyr and dicamba. The half-fruit method facilitates the screening of many potential drop inhibitors because treatments can be applied to single-limb-units at any time during the growing season.
Plant Cost Accounting: A Microcomputer Program to Calculate Crop Production Costs
Authors: Tripepi Robert R. , Kuchar Edward J.
Published: September 2022

Growers must know their production costs to be competitive and profitable. A microcomputer program has been developed to calculate these costs based on various production inputs involved in growing crops. The user enters costs for land, buildings, equipment, general overhead expenses, and cultural practices. The program produces cost summaries for capital requirements, annual fixed costs, variable cost per hour of equipment, estimated costs of production, and final price per plant. With this information, growers can compare their prices against those of competitors to determine if the crop will be profitable.
Vegetable Preferences of Home Gardeners
Authors: Neier Robert , Marr Charles
Published: September 2022

Knowing which vegetables are popular can focus the direction of program activities such as research or demonstration trials, news articles, radio and television releases, and publications. This information also is important in determining sales and supply strategies of vegetable seeds and related products. A national survey has given indications of the popularity of selected vegetables (1).
‘Earliscarlet’ Nectarine
Authors: Scorza Ralph , Fogle Harold W. , Gilreath L. E.
Published: September 2022

‘Earliscarlet’ nectarine [Prunus persica (L.) Batsch] was released in Apr. 1985 because of its attractiveness, high quality, and early season of ripening, a season when relatively few high quality nectarine cultivars for the eastern United States are available.
Rhizome Storage Increases Growth of Zantedeschia elliottiana and Z. rehmannii
Authors: Corr Brian E. , Widmer Richard E.
Published: September 2022

Zantedeschia elliottiana Engl. and Z. rehmannii W. Wats. rhizomes replanted immediately after leaf removal (without a period of storage) did not grow. Rhizomes replanted after leaf senescence, induced by withholding water, sprouted without an additional storage period, but height and number of leaves and shoots per rhizome were greater from rhizomes stored for ≥3 weeks. Rhizomes stored at 22°C for 6 weeks lost significantly more weight than rhizomes stored at 4° or 9°. Height and number of leaves and shoots per rhizome were greatest after 9° storage for both species, but differences were significant for Z. rehmannii only.
Ethephon Dip Concentration and Heat Curing Duration Influence Forcing Performance of Dutch Iris
Authors: Cascante Xenia M. , Doss Robert P.
Published: September 2022

When compared to non-ethephon treated bulbs, time to flowering of U.S.-grown Dutch iris (Iris hollandica Hoog) ‘Ideal’ and ‘Blue Ribbon’ was shortened by 14 and 27 days, respectively, by dipping bulbs for 1 hr in a solution of ethephon at a concentration of 0.25 g·liter–1 and then heat curing at 32°C for 3 days. This treatment also decreased leaf number and maximum leaf length. Thus, the plants were commercially more acceptable than those not treated with ethephon. With ‘Blue Ribbon’, treatment with ethephon at 5.0 g·liter–1 reduced flowering percentage relative to that obtained with several lower concentrations because of prevention of flower initiation. Chemical name used: (2-chloroethyl)phosphonic acid (ethephon).
Slow-release Fertilizers as Sources of Sulfur
Authors: Handreck Kevin A. , Correll Raymond L.
Published: September 2022

When the slow-release fertilizers Nutricote 13N–5.7P–9.1K (4–5 month) (N1), Nutricote 13N–5.7P–9.1K (8–9 month)(N2), Osmocote 15N–5.2P–12.5K (3–4 month)(01), Osmocote 18N–4.8P–8.3K (8–9 month) (02) and Osmocote Plus 15.4N–4.8P–10.8K (3–4 month)(03) were incorporated into Pinus radiata D. Don bark at a rate of 2 g·liter–1, S equivalent to about 8%, 0.6%, 17%, 16%, and 20%, respectively, of their S contents appeared in leachates over 64 days. Phlox drummondii Hook. ‘Candy’ were grown in a soilless potting mix containing N1, O1, or O3 at 3, 6, and 9 g·liter–1 alone or supplemented with gypsum and/or a dilute S-free liquid fertilizer. At 3 g·liter–1 addition, plants in N1 pots grew better with gypsum and liquid feed added separately and much better when both were applied. At 6 and 9 g·liter–1, neither gypsum nor liquid fertilizer increased shoot weights, but plants grown without gypsum were chlorotic, which was attributed to S deficiency. The combined addition of gypsum and liquid fertilizer to pots containing N1 at 6 and 9 g·liter–1 gave significantly larger shoot weights.
Internal Atmosphere of Onion Bulbs Stored at Various Oxygen Concentrations and Temperatures
Authors: Ladeinde Folusa , Hicks James R.
Published: September 2022

The internal atmosphere of onion (Allium cepa L.) bulbs after 3 months of storage at 20°C was 3.1% CO2/16.2% O2. Bulb size and sampling location within the bulb did not significantly influence the level of particular gaseous components. The equilibrium level of internal O2 was lowest at 30° and highest at 0° and was dependent on external O2 level. Wax applied to the root plate caused a dramatic reduction of internal O2 and elevation of CO2. There was less effect when only the neck of the bulb was waxed. The effect of waxing the base plate and neck was greater at 15° and 30° than at 0°.
Post-germination Root Growth in Lettuce: Role of Ethylene under Saline and Nonsaline Conditions
Authors: Huang X. -L. , Khan Anwar A.
Published: September 2022

The role of ethylene in the control of post-germination root growth of Lactuca sativa L. ‘Mesa 659’ was investigated in saline (0.1 m NaCl) and nonsaline media by the use of the ethylene absorbant Hg(ClO4)2 and the ethylene action inhibitors norbornadiene (NBD), silver thiosulfate (STS), and silver nitrate. Root growth was inhibited by 0.1 m NaCl, 0.32 to 1.6 µl·liter–1 ethylene, 0.35 mm ethephon, 0.05 mm kinetin, or 1mm ACC. Application of 1.0 to 4.0 ml NBD gas–air mixture or 0.001 to 1.0 mm STS enhanced the root growth in both saline and nonsaline media. The magnitude of response to NBD or STS under saline condition was greater or equal to that under nonsaline condition. NBD was most effective when applied at the time when the radicle was just protruding (1–2 mm). Kinetin or ACC inhibition of root growth was not reversed by NBD or AgNO3, indicating that such inhibition may not relate directly to ethylene action. We conclude that the sensitivity of lettuce roots to ethylene might be enhanced in saline medium even though growth may be reduced. Chemical names used: 1-aminocyclopropane-1-carboxylic acid (ACC); 2,5-norbornadiene (NBD); N-(2-furfurylmethyl)-1H-purine-6-amine (kinetin); and (2-chloroethyl)phosphonic acid (ethephon).
A Rapid Clearing and Staining Method for Tissue-cultured Plantlets and Greenhouse-grown Leaves
Authors: Tisdall Laurence , Donnelly Danielle J.
Published: September 2022

A simple, rapid clearing and staining method was developed using intact in vitro blackberry (Rubus spp. ‘Silvan’) and strawberry (Fragaria × ananassa Duch. ‘Totem’) plantlets and sections of greenhouse-grown ‘Silvan’ and ‘Totem’ leaves. The clearing method involved three steps: 1) autoclaving in 80% ethanol to remove the chlorophyll, which took 15 to 20 min for plantlets and 25 and 35 min for greenhouse-grown ‘Silvan’ and ‘Totem’, respectively; 2) dissolution of the protoplasm using 5% NaOH at 80°C, which took 20 min for plantlets and 35 and 40 min for greenhouse-grown ‘Silvan’ and ‘Totem’ respectively; 3) post-alkali treatment with 75% bleach (4.5% NaClO). For tissue-cultured plantlets this took 5 to 10 min at room temperature, but greenhouse-grown material required 35 to 40 min at 55°. Aqueous safranin (10 mg·liter−1) was used for staining. This method gave consistently good results and required a maximum of 2 hr for completion.
Guidelines for Autoclaving Liquid Media Used in Plant Tissue Culture
Authors: Burger David W.
Published: September 2022

The temperatures of liquid volumes (10–4000 ml) were monitored with solid-state temperature probes during autoclaving cycles of an automated steam sterilizer. Accurate measurements of the time required for the liquid volumes to reach the sterilizing temperature (121°C) were made. The effects of preheating solutions to be autoclaved and enclosing materials in autoclavable plastic bags were determined. Liquid volumes between 10 and 4000 ml differed in the time required to reach 121° by 40 min. Preheating solutions before autoclaving slightly reduced the time required to reach sterilizing temperatures. Enclosing materials in autoclavable bags substantially increased the time required to reach 121°.
Increased Rubber Content in Guayule after Honey Bee Pollination
Authors: Mamood Amed N. , Ray Dennis T. , Waller Gordon D.
Published: September 2022

Guayule (Parthenium argentatum Gray) is a small, woody perennial shrub native to the Chihuahuan desert region of north-central Mexico and southwest Texas. Its outstanding characteristic is the production of a high quality natural rubber. Guayule has long been recognized as a promising alternative domestic rubber source to that from the rubber tree, Hevea brasiliensis Muell. Arg. Enhanced rubber production has been the primary objective of the research and development effort since the late 1970s (7).
Net Photosynthetic Rates and Growth of Strawberry after Partial Defoliation
Authors: Kerkhoff Karen L. , Williams Jerry M. , Barden John A.
Published: September 2022

Leaf loss increased net photosynthesis (Pn) or delayed senescence of the remaining leaves in several plant species (2, 3, 7, 8). Strawberries are commonly defoliated during planting and after fruiting. The objective of this study was to determine the effects of partial defoliation on Pn rates and growth of the strawberry.
Ammonia Volatilization from Urea and an Experimental Triazone Fertilizer
Authors: Kissel David E. , Cabrera Miguel L.
Published: September 2022

Urea, a major source of N fertilizer for turfgrass, is susceptible to ammonia (NH3) volatilization when applied to the surface of turf (4) and soil (3). Urea hydrolyzes in the presence of urease and water to form ammonium ( and, in the process, raises soil pH (3). As a result, a portion of the formed can then be converted to gaseous NH3, part of which can volatilize into the atmosphere. Under certain environmental conditions, significant N loss may result (1).
Identification of a Peonidin-3-cinnamylsophoroside in the Flowers of Tabebuia impetiginosa
Authors: Bobbio Florinda O. , Bobbio Paulo A. , Degáspari Claudia H.
Published: September 2022

Tabebuia impetiginosa, a tall, fast-growing tree of the family Bignoniaceae, completely loses its leaves in May or June and becomes covered by large clusters of bluish pink flowers from May to July or August. Pomilio and Sproviero (8) found in the flowers of Argentine Tabebuia spp. three anthocyanins: cyanidin-3-glucoside, cyanidin-3-rutinoside, and peonidin-3-rutinoside. This paper reports the identification of a major anthocyanin present in the flowers of T. impetiginosa.
Horticulture in Oklahoma and at Oklahoma State University
Authors: Payne Richard N.
Published: September 2022

Oklahoma is a land of diversity in topography and climate. Elevations range from as low as 88 m above sea level at one location in southeastern Oklahoma to near 1520 m in the western panhandle. Although Oklahoma is part of the Great Plains, the state has four mountain ranges : The Ouachitas in the southeast, the Arbuckles in the south, the Ozarks in the northeast, and the Wichitas in the southwest. Rainfall varies from 1270 mm annually in the southeast to around 380 mm in the panhandle. The state average is 787 mm. The growing season ranges from 240 days in the southeast to 180 days in the panhandle. The state is blessed with abundant sunshine, and temperatures can range from below - 17.8°C in winter to > 37.8° in summer.
Soil Compaction Reduces Modulation, Module Efficiency, and Growth of Soybean and White Bean
Authors: Tu J. C. , Buttery B. R.
Published: September 2022

In the article “Soil Compaction Reduces Nodulation, Nodule Efficiency, and Growth of Soybean and White Bean”, by J.C. Tu and B.R. Buttery [HortScience 23(4):722–724, August 1988], the words “Modulation” and “Module” were used in the title instead of the correct “Nodulation” and “Nodule”. The title as noted here is correct.
Status of Horticulture in the Developing Countries of Southern Africa
Authors: Rice Robert P. , Rice Laura Williams
Published: September 2022

Horticulture has not been a priority in the agricultural development plans of southern Africa. Large advances have been made in the production of staple crops while horticultural production stagnated or declined. Governments in the Southern Africa Development Coordination Council (SADCC) region are now beginning to consider horticulture as a tool in improving nutrition, the income of their people, and national foreign exchange earnings. A number of constraints exist, however, including attitude, transport, postharvest handling, lack of horticulturists, seed and plant shortages, and poor communication. The potential of horticulture in the region is great if the governments and people of the region can meet the challenges of developing the horticultural industry.
Hydroponic Culture, Grafting, and Growth Regulators to Increase Flowering in Sweet Potato
Authors: Lardizabal Ricardo D. , Thompson Paul G.
Published: September 2022

Hydroponic culture of sweet potato [Ipomoea batatas (L.) Lam.] inhibited storage root formation and reduced flower numbers compared to peat-lite medium in three of four cultivars. Elevated levels of B, Mg, and Fe in the nutrient solution increased flower numbers in ‘Southern Delite’. Flower numbers in ‘Southern Delite’ also were increased by grafting onto Ipomoea carnea Jacq. ssp. fistulosa (Mart. ex Choisy) D. Austin. Grafting ‘Shore Gold’ onto I. carnea increased flower numbers when grown in peat-lite, but not in hydroponic culture. GA3 and ethephon produced higher flower numbers than the control treatment in ‘Shore Gold’, but ABA and BA did not. ‘Southern Delite’ did not respond to growth regulator application. Chemical names used: [S-(Z,E)]-[5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2,4-pentadienoic acid [abscisic acid (ABA)], N-(phenylmethyl)-1H-purin-6-amine (BA), (2,4-dichlorophenoxy) acetic acid (2,4-D), (2-chloroethyl) phosponic acid (ethephon), and (1α,2β,4aα,4bβ,10β)-2,4a,7-trihydroxy-1-methyl-8-methylenegibb-3-ene-1,10-dicarboxylic acid, 1,4a-lactone (GA3).
Nondestructive Detection of Core Breakdown in ‘Bartlett’ Pears with Nuclear Magnetic Resonance Imaging
Authors: Yi Wang Chien , Wang Paul C.
Published: September 2022

The development of core breakdown in ‘Bartlett’ pears (Pyrus communis L.) held at 20°C after 3 months of storage in air or in 1% O2 at 0° was monitored with nuclear magnetic resonance (NMR) imaging. Longitudinal NMR images of the fruit revealed the presence and severity of core breakdown. The progress of the disorder inside the fruit could be clearly seen without destroying the fruit. A distinct difference in the degree of core breakdown between air and low-O2 stored fruit could be discerned in the NMR images.
Identification of Vitis vinifera L. × Muscadinia rotundifolia Small Hybrids by Starch Gel Electrophoresis
Authors: Chaparro José X. , Goldy Ronald G. , Mowrey Bruce D. , Werner Dennis J.
Published: September 2022

Four isozyme systems, glucosephosphate isomerase (PGI, EC 5.3.1.9), phosphoglucomutase (PGM, EC 2.7.5.1), isocitrate dehydrogenase (IDH, EC 1.1.1.42), and malate dehydrogenase (MDH, EC 1.1.1.37), were identified as useful in detecting intergeneric Vitis vinifera × Muscadinia rotundifolia hybrids. Polymorphism between and within the two genera was observed at the PGI-2, PGM-2, and IDH-1 loci. However, the two appeared fixed for different alleles at the MDH-3 locus. The combination of any two of the enzyme systems allowed for rapid identification of F1 hybrids at the young, pre-fruiting seedling stage.
Improved Equipment for Vacuum Extraction of Saturated Growing Media
Authors: Hershey David R.
Published: September 2022

The saturated medium extract (SME) method of container media testing for pH, electrical conductivity (EC), and nutrient levels is generally considered the best procedure for research and routine analysis (1, 5-8). However, various soil : water ratio methods (e.g., 1:1.5, 1:2, 1:5) are widely used (1, 2), partly because they do not require a vacuum extraction, as does the SME method. The use of so many different methods creates considerable confusion (5). Vacuum extraction of saturated media is traditionally performed with a porcelain Buchner funnel ($26 for 9-cm size) and a side-arm, glass vacuum flask ($13 for 500ml size) (2, 6). Less-expensive, unbreakable polypropylene Buchner funnels and vacuum flasks are available. However, they have several disadvantages: they easily tip over when the Buchner funnel contains saturated media, are difficult to dry quickly if several samples need to be run in succession with only one vacuum flask, and only are available through scientific instead of horticultural suppliers.
Rare Allozymes of Malate Dehydrogenase in Pecan
Authors: Marquard Robert D.
Published: September 2022

Isozyme banding patterns, elucidated by starch gel electrophoresis, frequently are simply inherited and also useful tools in horticultural research (4). An earlier paper (1) documented that malate dehydrogenase (MDH; EC 1.1.1.37) in pecan is a dimer controlled by at least one polymorphic gene with two alleles (Mdh-1). Two of 66 pecan cultivars were characterized for Mdh-1 and produced an additional Mdh-1 band that remained unexplained (1). Results from controlled crosses confirm that two additional alleles exist for the Mdh-1 locus, but are rare among cultivars and occur at a frequency of about =1%. Controlled pollinations produced seedlings with MDH phenotypes not previously observed in pecan.
Horticultural Faculty Views on the Changing Role of the Cooperative Extension Service
Authors: Gerber John M. , Masiunas John
Published: September 2022

The Cooperative Extension Service (CES) is undergoing a period of self-evaluation (Gerber, 1985) and change (USDA Extension Service, 1988). As part of on-going discussions on the future of the CES at the Univ. of Illinois, a survey of the academic staff in the Dept. of Horticulture was conducted. The survey quantified the reaction of horticultural academic staff to recommendations taken from a federal study on the future of extension (USDA Economic Committee on Organization and Policy, 1987) and statements solicited from the Dept. of Horticulture Extension Committee. Recipients of the survey were asked to state their level of agreement or disagreement with the statements on a scale of 1 to 5 (1 = strongly disagree, 2 = disagree, 3 = no opinion, 4 = agree, and 5 = strongly agree).
‘TropicBeauty’: A Low-chilling Peach for Subtropical Climates
Authors: Rouse Robert E. , Sherman Wayne B.
Published: September 2022

‘TropicBeauty’ peach is released jointly by the Texas Agricultural Experiment Station of the Texas A&M Univ. System and the Florida Agricultural Experiment Station, Univ. of Florida.
‘Thunder Cloud’ Cenizo
Authors: Simpson Benny J. , Hipp Billy W. , McWilliams Edward L.
Published: September 2022

Several species of Leucophyllum are widely used in Texas and the southwestern United States (Arizona, California, Nevada, New Mexico) for amenity plantings. These taxa are among the most ornamental of all native Texas plants (8). Leucophyllum candidum I. M. Johnst. (2, 7) grows on arid sites in northern Mexico and in southern Brewster Co., Texas, and is usually found on caliche, gravelly hillsides (11). The low requirements for nutrients, water, pest control, and general maintenance make the use of ‘Thunder Cloud’ a pragmatic choice for water and energy conservation in the arid to semi-arid southwest (12).
Physiology and Control of Superficial Scald of Apples: A Review
Authors: Ingle Morris , D’Souza Mervyn C.
Published: September 2022

Superficial scald (storage, common scald) is an extensively studied postharvest physiological disorder of apples. Research on superficial scald of apples before 1965 was reviewed by Hardenburg (26); that reported since is summarized in this paper.
A Statistical Editor’s Viewpoint of Statistical Usage in Horticultural Science Publications
Authors: Nelson Larry A.
Published: September 2022

Other authors in this series are dealing with the technical aspects of statistical applications, such as experimental design and data analysis. This paper deals more with the reporting phase. But, because this phase is not a phase unto itself, we need to look at all interfaces of statistics and horticultural science research.
Growth and Development of Young Peach Trees as Influenced by Foliar Sprays of Paclobutrazol or XE-1019
Authors: Liyembani Samutumwa , Taylor Bradley H.
Published: September 2022

A single or four sequential foliar sprays of paclobutrazol (PBZ) and XE-1019 (Valent Corp., Walnut Creek, Calif.) to peach [Prunus persica (L.) Batsch.] supplied, respectively, 7.5 to 480 mg a.i. and 0.75 to 48 mg a.i. doses per tree. These treatments reduced the net change in total shoot length (current-season extension shoots plus lateral shoots) occurring over the 15-week period after the sprays were applied by up to 80% and 69%, compared to the control, for each compound, respectively. The average number of lateral shoots was decreased 85% and 81% by the highest dose of each material. The shoot and whole plant dry weight at the end of the growing season (15 weeks after treatment) were ≍22% and 27% lower than the control for PBZ and XE-1019, respectively. Trunk cross-sectional area, leaf area, and dry weight of leaves and roots were also smaller on the trees treated by either compound. Root : shoot ratios were not influenced by any treatment. Chemical names used: β-[(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazole-1-ethanol (paclobutrazol); (E)-1-(p-chlorophenyl)-4-,4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol (Valent XE-1019).
Irrigation Water Management for Bush Snap Bean Production
Authors: Singh Bharat P.
Published: September 2022

The effect of various amounts of irrigation on vegetative growth and pod yield of bush snap beans (Phaseolus vulgaris L.) was investigated. The field experiments were carried out during 1985 and 1986, years of abundant and limited rainfalls, respectively. Evaporation from a National Weather Service type open pan (Epan) was used to determine the timing and amount of irrigation. Vegetative growth was estimated from the number of leaves, leaf area, and leaf and stem dry weights. Irrigation significantly increased vegetative growth and pod yield. Pod yield/unit of irrigation water was maximum at 60% Epan. Vegetative growth increased linearly from irrigation amounts of 0% to 100% Epan, while pod yield enhancement ceased above 80% Epan. The study suggested an irrigation schedule based on 80% Epan for highest bush snap bean production.
Whole Leaves Versus Petioles for Assessing the Nitrogen Status of Tomatoes
Authors: Minotti Peter L. , Hankinson Thomas J. , Grubinger Vernon P. , Christian Wien H.
Published: September 2022

Tomatoes (Lycopersicon esculentum Mill.) were sampled for laboratory analysis of nitrate nitrogen (NO3-N) in one greenhouse and four field experiments. A ratio of about 3:1 (petiole NO3-N to whole leaf NO3-N) was found over a wide range of conditions for the third leaf below the growing tip and leaves further below this point. The ratio was higher for the very youngest leaves. Nitrate-N increased with leaf age and then remained relatively constant. Whole leaves proved just as effective as petioles for reflecting changes in available N.
Reaction of Crop Species to Thiocyanate Ion Toxicity
Authors: Stiehl Barbara , Bible Bernard B.
Published: September 2022

Little evidence is available concerning possible allelopathic effects of the thiocyanate ion (SCN-), a known toxin commonly found in plants of the Brassicaceae (crucifers). Seeds and seedlings of 39 species of crop plants were exposed to ionic thiocyanate (0.5 mM SCN- supplied as KSCN) to determine their relative sensitivity. Percent germination was unaffected by SCN- for all the species tested. Thiocyanate ion inhibited the total seedling (shoot and root) extension of 46% of the species tested, with 38% of the species showing inhibition of shoot and 49% showing inhibition of root extension. This demonstrates that SCN- has the capacity to harm a range of species. However, the toxicity was selective in that 44% of the test species were unaffected by exposure to SCN-. Wide differences in seed weight among species, in incubation time, and also systematics were major sources of variation for species sensitivity to SCN-.
Educational Institutions Offering Horticulture and/or Landscape Architecture in the United States and Canada
Authors: Childers Norman F.
Published: September 2022

This directory of institutions offering horticultural and/or landscape training in the United States and Canada has been assembled for use by ASHS Members and administrators and teachers of horticulture. This effort is a continuing part of the activities of the Education Division of ASHS.
Introduction to Workshop on the Use of Alternative Energy Sources in Horticulture
Authors: Sanderson Kenneth C.
Published: September 2022

Energy is like the air that we breathe, something that we have taken for granted for far too long. Almost every decade we have seen increased, almost insatiable, demands for more energy with little concern for supply or price. In the past decade, a grave threat to our national security as a result of our extensive dependence on unstable foreign oil supplies and escalating energy costs sobered up our energy thinking.
Iron Availability in Rockwool may Affect Rose Nutrition
Authors: Rupp Larry A. , Dudley Lynn M.
Published: September 2022

Rockwool is an inert medium for use in greenhouses. It is reported to contribute negligible nutrients to plants. However, Rosa multiflora ‘Burr’ rootstocks grown in Grodan rockwool exhibited no visible Fe chlorosis with an Fe-free nutrient solution. Leaf chlorophyll content was 2.65 mg·g-1 with Fe and 2.85 mg·g-1 without Fe. Available Fe concentrations of three commercial materials (Hortiwool, Grodan block, and Grodan loose), estimated by using diethylenetriaminepentaacetic acid (DTPA) extraction (2 DPTA : 1 rockwool, v/w), were 43.0, 0.33, and 3.95 mg Fe/liter, respectively. With long-term DTPA extractions (20:1), Fe extracted from Hortiwool and loose Grodan increased for ≈3 days before leveling off, while Fe extracted from Grodan block increased for 6 days. Measurable levels of Mn, Cu (348 mg·liter-1), and Zn were found in DTPA extracts of Hortiwool; measurable levels of Mn and Cu were extracted from loose Grodan and measurable levels only of Mn from Grodan block.
The Palmette Leader: A Tree Design for Improved Light Distribution
Authors: Lakso Alan N. , Robinson Terence L. , Carpenter Steven G.
Published: September 2022

A tree design, called the “palmette leader”, for improving the distribution of light within the tree canopy is described. The tree is a modification of the common central leader, and is formed by having a complete lower whorl of scaffold branches with a flat north-south-oriented palmette leader above. The large permanent gaps in the upper canopy ensure good light distribution, which was confirmed with canopy transects using fisheye photography. Preliminary evaluations of tree performance with ‘McIntosh’ apples (Malus domestica Borkh.) indicated that cumulative yields, fruit soluble solids content, and fruit dry matter were greater than well-trained central leaders, but fruit size and fruit color were similar. The improved light penetration into the center of the palmette leader compared to the central leader was found to induce higher photosynthesis of interior spur leaves exposed by summer pruning in August. Management of the palmette leader trees was found to be relatively simple.
Floral Induction in 2n and 4n Dieffenbachia maculata ‘Perfection’ After Treatment with Gibberellic Acid
Authors: Henny R. J.
Published: September 2022

Autotetraploid (4n) plants of Dieffenbachia maculata (Lodd.) G. Don ‘Perfection’ flowered poorly, compared to diploids (2n), following treatment with 250 or 500 mg foliar spray of gibberellic acid (GA3)/liter. GA3-treated 4n plants produced bracts that normally precede flowering but remained vegetative and produced additional distal shoots instead of flowers.
Methods for Premixing Gases in Pressurized Cylinders for Use in Controlled Atmosphere Experiments
Authors: Peterson Sharon J. , Lipton Werner J. , Uota Masami
Published: September 2022

Methods for mixing various concentrations of O2, CO2, N2, and C2H4 in high-pressure cylinders are described. The concentrations are mixed by partial pressure or partial volume and then are verified by gas chromatography. The procedures generally allow for a precision of ±5% when either 1.0% O2 or CO2 or higher concentrations are mixed with N2 or when C2H4 at 100 µl·liter-1, or more, is added. For lower concentrations, or when both O2 and CO2 are combined with N2, then the precision is ±10%.
Duration of Imbibition Affects Seed Leachate Conductivity in Sweet Corn
Authors: Schmidt D. H. , Tracy W. F.
Published: September 2022

Seed leachate conductivity (SLC) has been evaluated as a possible method of measuring seedling vigor in sweet corn (Zea mays L.) and other crops. It is known that genotypes leak solutes at different rates. Thus, it is important to determine if the different rates of leakage result in different SLC determinations when SLC is measured after various lengths of imbibition. A study was conducted using near-isogenic lines of three inbreds (C68, P39M94, and Ia5125a) in combination with five endosperm types, sugary dull (su du), sugary sugary-2 (su su2), sugary dull waxy (su du wx), shrunken-2 (sh2), and sugary (su), to evaluate the effect of length of imbibition and the interaction of imbibition length and endosperm type and inbred background on conductivity. Readings were taken at 0, 2, 4, 6, 8, 10, 12, 14, and 24 hr after the start of imbibition. Conductivity was affected by length of imbibition, inbred background, and endosperm-type main effects and interactions of these effects. Conductivity increased with increasing time after imbibition. Ranking of endosperm types within each inbred was stable by 2 hr after imbibition, although differences were not always significant. Thus, the interaction effects were due to an increasing separation over time and not to a change in ranking of the genotypes. However, means separation was greatest at 24 hr after imbibition.
Comparison of Procedures for Estimating Viability of Prunus Pollen
Authors: Parfitt Dan E. , Ganeshan S.
Published: September 2022

Seven assays (hanging-drop slide and agar-plate germination, acetocarmine, three tetrazolium-based stains, and Alexander’s staining procedures) were used to estimate pollen viability in Prunus armeniaca L., P. avium L., P. dulcis Webb, P. persica (L.) Batsch, and P. salicina Lindl. The two in vitro germination tests (hanging-drop and agar-plate) were the most reliable and were highly correlated (r = 0.96). The pollen staining procedures were not reliable or consistent and were not positively correlated with the in vitro assays. Acetocarmine and Alexander’s stains stained dead pollen.
Isolation and in Vitro Translation of RNAs from Developing Peach Fruit
Authors: Callahan Ann , Morgens Peter , Walton Eve
Published: September 2022

Peach [Prunus persica (L.) Batsch] RNA was extracted from fruit at six times during development, from leaves and from isolated ovules. These RNAs were translated in a wheat germ extract and the resulting polypeptides were compared by one-dimensional NaDodSO4/PoIyacrylamide gel electrophoresis (PAGE). RNAs encoding polypeptides of 100,85, 59,54,42, 41, and 25.5 kDa increased, while those encoding polypeptides of 46, 40, 25.5, and 25 kDa decreased during peach fruit development. These RNAs are present in fruit but not in ovules or leaves. This study suggests that fruit development in peach is at least partially regulated at the transcriptional level or at the level of mRNA stability.
Interspecific Hybrids Between Two Chrysanthemum Species
Authors: de Jong J. , Rademaker W.
Published: September 2022

Dendranthema pacificum Nakai (Chrysanthemum pacificum Nakai; 2n = l0x = 90 chromosomes), a species native to Japan, was crossed to Dendranthema grandiflora Tzvelev (C. morifolium Ramat.; 2n = 6x = 54), the florist chrysanthemum, to develop a type with numerous small flowerheads. The first-generation hybrid was fertile, but the flowerheads were too small. In the first backcross to D. grandiflora, the desired type was obtained. The backcross (2n = 7x = 63) was very fertile, despite the odd number of genomes. D. pacificum may also be used as a source of resistance to the serpentine leaf miner (Liriomyza trifolii).
In Vitro Shoot Regeneration on Leaf Tissue from Micropropagated Highbush Blueberry
Authors: Callow P. , Haghighi K. , Giroux M. , Hancock J.
Published: September 2022

Leaf explants from shoot-proliferating cultures of highbush blueberry (Vaccinium corymbosum L.) produced shoots on one-half-strength Murashige and Skoog medium (MS) supplemented with 5, 25, 50, or 100 μmol of 2iP. The highest number of meristematic nodules and buds per leaf were induced at 25 μmol 2iP and the least at 5 or 100 μmol. Nodule, bud, and shoot regeneration was significantly increased by wounding the leaf explants. Chemical name used: 6(γ-γ-dimethylallylamino)purine (2iP).
In Vitro Propagation of Lavender
Authors: Calvo Maria Carmen , Segura Juan
Published: September 2022

Cultures were established for micropropagation of Lavandula latifolia Medicus from hypocotyl explants. Bud induction was achieved by placing the explants on Murashige and Skoog (MS) medium supplemented with 0.60 μM IAA and 8.9 μM BA. The buds developed into numerous shoots on transfer to several elongation media. Shoots were easily rooted (95%) on MS hormone-free medium with macronutrients at half-strength. Plantlets were successfully transplanted into soil. Chemical names used: N-(phenylmethyl)-1H-purin-6-amine (BA); 1H-indole-3-acetic acid (IAA).
Estimating Price Elasticity for Fresh Flower Bouquets Sold In Supermarkets
Authors: Timothy Rhodus W.
Published: September 2022

A controlled pricing experiment was conducted in three rural and three urban supermarkets as a means of identifying consumer preferences for fresh flower bouquets. Impacts on consumer demand due to type of bouquet, location of store, day of week, and selling price were analyzed. Rural and urban consumers were found to exhibit different preferences for bouquets. Sales patterns throughout the week exhibited slack sales on Monday through Thursday, followed by a sharp increase on Friday through Sunday. Consumer demand for bouquets can be characterized as price-elastic.
‘Flordastar’ Peach
Authors: Sherman W. B. , Lyrene P. M.
Published: September 2022

‘Flordastar’ peach [Prunus persica (L.) Batsch] is released for grower trial by the Florida Agricultural Experiment Station (Fig. 1). This cultivar bears attractive, yellow-fleshed fruit that ripen before ‘Flordaprince’ in central Florida.
‘Sovereign Tiara’ Grape
Authors: Reynolds A. G. , Denby L. G. , Bouthillier M. , Strachan G. E.
Published: September 2022

‘Sovereign Tiara’ (Vitis spp. hybrid) is the second of two white wine grape cultivars recently released by the Agriculture Canada Research Station, Summerland, B.C. Like ‘Sovereign Opal’ (1), ‘Sovereign Tiara’ is a late-midseason grape cultivar useful for both varietally labeled and proprietary products. Consistently high yields make ‘Sovereign Tiara’ ideal for use as a bulk blending grape, and render it advantageous over ‘Sovereign Opal’ for this purpose. Compared to ‘Okan-agan Riesling’, yield and winter hardiness of ‘Sovereign Tiara’ are superior, while fruit composition is comparable.
Temperature-conditioning Affects Polyamines of Lemon Fruits Stored at Chilling Temperatures
Authors: McDonald Roy E.
Published: September 2022

Chilling injury (CI) of lemons (Citrus limon Burm. f.) was reduced by temperature-conditioning at 10, 15, 21, or 27C immediately before storage at 1C. CI was less severe in lemons temperature-conditioned for 7 vs. 3 days. However, the process is not recommended for avoiding CI in lemons stored at low temperatures because of the wide range in treatment effects. Following conditioning at 21 and 27C, putrescine concentrations increased in flavedo tissue and were also higher in fruit after storage at 1C than at 10C, regardless of conditioning temperature. After holding fruit for 2 weeks at 21C, putrescine levels were higher in lemons that had been stored at 10C than in those stored at 1C. Prestorage temperature-conditioning did not affect spermidine levels, which tended to be higher in fruit stored at 10C than at 1C after storage and subsequent holding at 21C.
Screening Tomato for High-temperature Tolerance Through Pollen Viability Tests
Authors: Weaver M. L. , Timm H.
Published: September 2022

A study was undertaken to determine a) if genotypic responses for fruit set and pollen viability in tomatoes (Lycopersicon esculentum Mill.) exposed to high temperatures are related, and b) if pollen viability at high temperature could be used to screen tomato plants for better performance in high-temperature environments. Fruit set, pollen germination, and pollen tube length varied among tomato sources exposed to 40C for 60 min, and both pollen germination (r = 0.988***) and pollen tube length (r = 0.815**) correlated positively with fruit set. Differentiation among tomato sources for increased pollen viability at high temperature was accelerated by increasing the temperature at which flowers were exposed from 40 to 48C. Pollen viability has a major role in determining the fruit set of tomatoes at high temperatures and can serve as a basis of screening for tomato plants that will potentially produce higher fruit yield in high-temperature environments.
Callus Production and Somatic Embryogenesis from White Ash
Authors: Preece John E. , Zhao Ji-liang , Kung Fan H.
Published: September 2022

In the article “Callus Production and Somatic Embryogenesis from White Ash”, by John E. Preece, Ji-liang Zhao, and Fan H. Kung [HortScience 24(2):377–380, April 1989], the authors wish to note the following: In Table 3, “2,4-D” should replace “NAA” under the heading “PGR in primary (DKW) medium”.
Triploid Watermelon Seed Orientation Affects Seedcoat Adherence on Emerged Cotyledons
Authors: Maynard Donald N.
Published: September 2022

Seedcoat adherence to emerged cotyledons of seedless watermelons (Citrullus lanatus (Thunb.) Matsum & Naki) results in distortion of seedlings that effectively restricts the number of productive plants in a planting. Significantly fewer seedcoats adhered to cotyledons when seeds were oriented with the radicle end up at a 45° or 90° angle than when seeds were oriented horizontally or with the radicle end down at a 45° or 90° angle. Emergence was not affected by seed orientation.
Summer and Fall Moisture Stress and Irrigation Scheduling Influence Pecan Growth and Production
Authors: Stein Larry A. , McEachern George Ray , Storey J. Benton
Published: September 2022

Summer and fall irrigation treatments increased pecan yield, trunk diameter, and percent kernel over nonirrigated trees. Sticktights and viviparous nuts were reduced by late-season irrigation in a dry year (1984). All irrigation treatments increased pecan size; the most frequently irrigated plots had the largest pecans and least tree water stress as measured by a pressure bomb in 1984. The less water was applied in Sept, and Oct. 1984, the more sticktights resulted. Late-season water stress in all treatments indicated that water was needed just before shuck opening.
Physiological Changes in Yellow Summer Squash at Chilling and Nonchilling Temperatures
Authors: McCollum T. G.
Published: September 2022

Summer squash (Cucurbita pepo L.) fruit were harvested 8 ± 1 day after anthesis and held at 2 or 15C. Samples were transferred from 2 to 15C after 3, 6, 9, or 12 days of storage. Respiration and ethylene production were measured 24 and 48 hr after fruit had been transferred to 15C. Electrolyte leakage from pericarp disks was determined 48 hr after transfer to 15C. Weight loss during storage was greater at 15 than at 2C; however, chilled fruit had a greater rate of weight loss after transfer to 15C than did nonchilled fruit. Surface pitting became obvious after 6 days at 2C and was progressively more severe with increased duration of chilling. Respiration rates of nonchilled fruit decreased with increased storage duration, whereas respiration rates of chilled fruit increased with increased storage duration. Ethylene production was <0.1 nl g-1hr-1 in nonchilled fruit. Ethylene production was enhanced in chilled fruit and increased with increased duration of chilling to a peak of 1.5 nl-g-1-hr-1 after 9 days at 2C, then decreased. Electrolyte leakage was not influenced by chilling.
Long-term Storage of Broccoli under Controlled Atmosphere
Authors: Makhlouf J. , Castaigne F. , Arul J. , Willemot C. , Gosselin A.
Published: September 2022

Controlled atmosphere (CA) conditions were assessed for long-term broccoli (Brassica oleracea L. Italica Group) storage. Broccoli was stored for 6 weeks at 1C under N2 containing the following percentages of CO2/O2: 0%/20%; 10%/20%; 6%/2.5%; I0%/2.5%; and 15%/2.5%. Color and chlorophyll retention was better under CA than in air. This improved retention was mainly due to increased CO2 concentration. Storage under CA also delayed the development of soft rot and mold. However, after 6 weeks of storage under an atmosphere containing 10% or more CO2, the rate of respiration increased simultaneously with the development of undesirable odors and physiological injury. Among the atmospheres tested, 6% CO2 and 2.5% O2 was the best for long-term (>3 weeks) maintenance of broccoli quality while avoiding physiological injury.
Mechanical Stress Stimulates Peroxidase Activity in Cucumber Fruit
Authors: Miller A. Raymond , Kelley Thomas J.
Published: September 2022

Peroxidase activity was determined in cucumber fruit (37 to 55 mm in diameter) subjected to mechanical stress followed by storage at 25C and 100% RH. Compared to unstressed, unstored control fruit, severe mechanical stress stimulated total extractable peroxidase activity after 24 and 48 hr of storage. Moderate mechanical stress or storage alone stimulated peroxidase activity to lesser degrees. Peroxidase isozyme analysis by native polyacrylamide gel electrophoresis showed that cucumber anodic peroxidases could be separated into slow-, moderate-, and fast-migrating groups. Both moderate and severe mechanical stress caused the appearance of a new slow-migrating peroxidase isozyme immediately after treatment. This slow-migrating isozyme disappeared after 24 hr of storage, then reappeared after 48 hr. Severe stress induced the appearance of two additional moderate-migrating peroxidases 24 hr after treatment. The same fast-migrating isozymes were also present in unstressed and moderately stressed fruits stored for 48 hr. Hence, using peroxidase as an indicator, it appears that mechanical stress induces an accelerated aging of processing cucumber fruit.
In Vitro Propagation of Leucospermum Hybrid, ‘Hawaii Gold’
Authors: Kunisaki J. T.
Published: September 2022

Axillary shoots of Leucospermum conocarpodendron (L.) St. John x L. cu-neiforme (N.L. Burm.) Rourke ‘Hawaii Gold’ were induced to proliferate in liquid basal medium of half-strength Murashige and Skoog inorganic salts (1/2-MS), 0.25 mg·liter-1 each of pyridoxins· HCl and nicotinic acid, 0.2 mg thiamine· HCl/liter, and 2% sucrose, supplemented with 0.2 mg BA/liter. Proliferations grew most rapidly in 0.25 mg BA/liter liquid medium and developed shoots when placed on filter paper bridges. Microcuttings were rooted by dipping in 50 or 100 mg·liter-1 IBA/liter solution and culturing in agar medium of basal nutrients. Rooted cuttings were successfully established in potting medium. Chemical names used: N-(phenylmethyl)-1H-purin-6-amine (BA); 1H-indole-3-butyric acid (IBA).
Easily Constructed, Inexpensive, Hydroponic Propagation System
Authors: Hershey David R.
Published: September 2022

Shoot or leaf cuttings can be rooted in flats of perlite under intermittent mist for use in a static solution culture system (Hershey and Merritt, 1986). However, removing perlite from the roots before transfer to hydroponics is tedious and damages the roots; also, all the perlite cannot be removed, which causes errors in dry mass and nutrient concentration determinations. A hydroponic propagation system was constructed of inexpensive, readily available materials that allowed rooting of large numbers of cuttings under intermittent mist.
‘Dark Lance’ False Indigo
Authors: Simpson Benny J. , Hipp Billy W. , McWilliams Edward L.
Published: September 2022

Amorpha fruticosa L. has a national distribution from the American west coast to the east coast and from Wyoming to Sonora, Mexico (Correll and Johnston, 1970). There has been much confusion, due to the large amount of variation that exists, as to the correct botanical nomenclature of the species. A tentative nomenclature change would leave A. fruticosa with at least 16 synonyms (Kartesz and Kartesz, 1980). The cultivar discussed would be listed by some authors under A. fruticosa L. var. angustifolia Pursh. (Correll and Johnston, 1970; Shinners, 1972). ‘Dark Lance’ was selected for its beauty of spring flowering, being literally covered with dense spikes of violet flowers with yellow-orange anthers in late April. This floral display is apparent for 7 to 14 days, depending on weather conditions. This is a desirable landscape plant with low requirements of fertilizer and maintenance, and apparent freedom from disease and insect pests. However, it is the first Texas A&M Univ. resource-efficient plant released to the Texas and southwestern nursery industry that does not have strong drought tolerance.
‘Rachel’ and ‘Jan Cochran’ Carla Azaleas
Authors: Fantz Paul R. , Michael Benson D. , Skroch Walter A.
Published: September 2022

‘Rachel’ and ‘Jan Cochran’ are Carla hybrid azaleas released in 1988 by the North Carolina Agricultural Research Service. Cold hardiness; later-blooming, semidouble, floriferous flowers; and moderate resistance to root rot were the objectives leading to selection and increase of ‘Rachel’. Cold hardiness, later-blooming floriferous flowers, moderate resistance to root rot and the unique, compact growth form resembling an English boxwood were the objectives leading to selection and increase of ‘Jan Cochran’. Stock plants have been made available to commercial nursery growers for propagation and distribution in the nursery industry.