bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevention of Postharvest Stress Cracks in Husked Coconuts during Transit1
Authors: Bruton B. D.
Published: August 2022

In a stratified shipment of coconuts (Cocos nucifera L.), stress cracks occurred more frequently in the top of the load. Stress cracks and coconut weight loss were directly related. Of the total number of cracked coconuts, 81% occurred within the top section of the load, 10% in the middle, and 9% in the bottom section; while 43% of the total weight loss occurred within the top section, 27% in the middle, and 30% in the bottom section. The average percentages of cracked coconuts for each treatment over all 3 sections were 13.1% for the nonwaxed control, 5.2% for carnauba wax-treated, and 0.4% for paraffin wax-treated.
The Effect of Selected Soil Factors on Growth and Nutrient Content of Highbush Blueberry (Vaccinium corymbosum L.)1
Authors: Reich Lee A. , Korcak R. F. , Thompson A. H.
Published: August 2022

‘Jersey’ blueberry plants were greenhouse-grown through 1 season with treatments consisting of a factorial combination of 4 soil factors: inoculation with a mycorrhiza-forming fungus; high or low nutrient regime; with or without leachate from a native blueberry soil; and soil porosities corresponding to a clayey, silty, or sandy, and a native blueberry soil, Berryland, as a standard comparison. Although very low in nutrient elements, Berryland soil or its leachate significantly increased plant growth. There was no significant effect on growth from mycorrhizal inoculation at either high or low nutrient levels and only a slight effect from varying the soil free-pore space.
Tree Development, Yield, and Fruit Quality of Two Orange Cultivars on Three Rootstocks in the Negev Region of Israel1
Authors: Levy Yoseph , Mendel Kurt
Published: August 2022

The influence of 3 rootstocks on growth, production, fruit quality, and leaf nutrients of old line ‘Washington navel’ and ‘Shamouti’ oranges [Citrus sinensis (L.) Osb.] was evaluated during a 23-year period for trees growing on loess soil in the northern Negev region of Israel. Highest production was of ‘Washington navel’ on Rough Lemon (C. jambhiri Lush), and lowest yield was ‘Shamouti’ on Cleopatra mandarin (C. reshnii Hort. ex Tan.). Fruit size of the 2 cultivars was largest on Rough Lemon and smallest on Cleopatra. Total soluble solids and acid were reduced by Rough Lemon. ‘Shamouti’ leaf K and B were increased and Mg decreased by Rough Lemon. P was lower in ‘Shamouti’ on sour orange (C. aurantium L.). Yields declined during the last years of the experiment, mainly due to crowding.
The Effect of Supplemental High Pressure Sodium Lighting and Nutrition on Vegetative Growth and Flowering of ‘White Marble’ and ‘Improved Mefo’ Cut Chrysanthemums1
Authors: Hughes Becky R. , Tsujita M. J.
Published: August 2022

Chrysanthemum morifolium Ramat. cvs. White Marble and Improved Mefo were rooted and grown in cell paks for 34 days under ambient light plus: photoperiodic incandescent night-break lighting 2μE (m−2s−1); 64 μE m−2s−1 high pressure sodium (HPS) dusk to dawn lighting; or 126 μE m−2s−1 HPS dusk to dawn lighting. Container-grown chrysanthemums were fertilized with either 200 ppm N, 86 ppm P and 166 ppm K or 300 ppm N, 129 ppm P and 249 ppm K with every irrigation. After 34 long days these plants were transplanted into raised beds, immediately given short day conditions, and treated as a normal commercial crop. The container-grown treatments were compared to each other and to a bench-grown control which received a total of 48 long days. Supplemental HPS lighting increased the net assimilation rate (NAR), plant dry weight, and height of ‘White Marble’ chrysanthemums after 4 weeks. Increased fertility increased NAR and dry weight in the supplemental light treatment but not in the ambient light treatment. Results were less obvious for “Improved Mefo’. The container-grown treatments were ready for harvest 14 to 22 days before the controls. In both cultivars the high light-high fertility treatment was superior to the other container-grown treatments. The ‘White Marble’ high light-high fertility treatment produced higher quality chrysanthemums than the control, while the same ‘Improved Mefo’ treatment produced chrysanthemums slightly inferior to the control.
Ozone and Sulfur Dioxide Sensitivity of Petunia: Modification by Ethylenediurea1
Authors: Cathey H. M. , Heggestad H. E.
Published: August 2022

N-[2-(2-oxo-l-imidazolidinyl)ethyl]-N’-phenylurea, (EDU or ethylenediurea) reduced the sensitivity of petunia plants (Petunia hybrida Vilm.) to ozone when treated with foliar or root applications. For most plants, EDU gave protection from visible injury within 24 hours of its application as a spray or soil drench. It was much more effective than butanedioic acid mono-(2,2-dimethylhydrazide) (daminozide) as a protectant from ozone injury. The activity of EDU was unaffected by the addition of a surfactant to the spray solution or soil drench, by day length, light conditions, temperature, and physiological preconditioning of the plants. Protection from injury by ozone lasted for at least 14 days. Furthermore, a concentration of 500 ppm either as a foliar spray of 1 to 2 ml per plant or as a soil drench of 100 ml per 10-cm diameter pot protected an ozone sensitive cultivar, ‘Snow Magic,’ the moderately sensitive cultivars, ‘White’ and ‘Pink Cascade,’ and the least sensitive cultivars, ‘Comanche Improved’ and ‘Sugar Plum’. Treatment with EDU afforded no protection against sulfur dioxide exposure doses which produced acute injury.
Ethylene Generation, Temperature Responses, and Relative Biological Activities of Several Compounds with Potential for Promoting Abscission of Sour Cherry Fruit1
Authors: Olien William C. , Bukovac Martin J.
Published: August 2022

Five compounds were evaluated for consistent promotion of sour cherry (Prunus cerasus L. cv. Montmorency) fruit abscission under field conditions: (2-chloroethyl)phosphonic acid (ethephon); 2-chloroethyl-tris-(2-methoxyethoxy)-silane (CGA 13586); 2-chloroethyl-methylbis-(phenylmethoxy)-silane (CGA 15281); 1,1,5,5-tetra-methyl-3-dimethylaminodithiobiuret (ER 3952), and beta-hydroxyethylhydrazine (BOH). The compounds were applied to mature trees at equimolar concentrations, and rates of ethylene evolution, effects of temperature on rates of ethylene evolution, and fruit removal forces were measured. Ethephon generated ethylene at adequate rates and was a good promoter of fruit abscission, but its activity was markedly affected by temperature. CGA 15281 promoted fruit abscission with minimal effect of temperature on ethylene evolution. ER 3952 was also a good fruit loosener, although it did not release ethylene directly. CGA 13586 and BOH were not effective in promoting fruit abscission and were poor ethylene generators.
Resistance of Ivy Geraniums to the Twospotted Spider Mite1
Authors: Potter D. A. , Anderson R. G.
Published: August 2022

Resistance to the twospotted spider mite (Tetranychus urticae Koch) of 18 cultivars of ivy geranium [Pelargonium peltatum (L.) L’Her ex Ait.] was evaluated under greenhouse conditions by mass screening, by measuring fecundity on isolated leaves, and by paired leaf tests for selected cultivars. ‘Sybil Holmes’, ‘Yale’, and ‘Cornell’ were among the most susceptible, whereas ‘Double Lilac White’, ‘Sunset’, and ‘Salmon Queen’ were relatively mite-free. ‘Madeline Crozy’ and ‘Cornell’ were preferred for oviposition over the resistant ‘Double Lilac White’. Mite resistance was not related to density of simple or glandular leaf trichomes, but there was an apparent relationship between mite susceptibility and severity of oedema.
Influence of Cultivar, Extraction and Storage Temperature, and Time on Quality of Muscadine Grape Juice1
Authors: Sistrunk W. A. , Morris J. R.
Published: August 2022

A processing study was conducted on 2 cultivars, 3 extraction temperatures, 3 storage temperatures and 3 storage times to assess differences in quality of juice of muscadine grape (Vitis rotundifolia Michx.) The 2 cultivars responded differently to all other variables in color changes. ‘Carlos’, a bronze-skinned grape was higher in acidity and lower in pH and total phenols than ‘Noble’, a black-skinned cultivar. Higher extraction temperatures leached out more acids, total phenols, and color. Color and overall quality changes were rapid at 32°C storage, making the juice unacceptable at 7 months storage. Greater changes in quality occurred when juice was extracted at 60° than at 24° or 80°.
Economics of Conversion to the Geneva Double Curtain Training System of ‘Concord’ Grapes1
Authors: Markin A. R. , White G. B.
Published: August 2022

A net present value analysis was conducted for the conversion from the Umbrella Kniffin training system to the Geneva Double Curtain training system for growing ‘Concord’ grapes (Vitis labruscana Bailey) in New York. The optimal cultural considerations included no overcropping and following a trunk renewal plan. For the optimal plan, conversion to the Geneva Double Curtain system was found to be a profitable investment alternative.
Cavity Spot of Carrots Caused by Feeding of Fungus Gnat Larvae1
Authors: Hafidh Fawzi T. , Kelly W. C.
Published: August 2022

The root defect of carrot (Daucus carota L.) called cavity spot is injury due to feeding of the fungus gnat larvae, Bradysia impatiens (Joh.). In sand cultures and in the field, carrots treated with the systemic insecticide, aldicarb (2-methyl-2(methylthio) propionaldehyde 0-(methylcarbamoyl) oxime) were free of the defect. The symptoms of cavity spot on carrot roots grown in sand culture were the same as those on field-grown roots. Eliminating Ca from the nutrient solution reduced the Ca content of roots and leaves but had no effect on the incidence of cavity spot. Plants with Ca-deficiency symptoms on the foliage produced roots that, except for size, were indistinguishable from roots of plants receiving the complete nutrient solution.
Postharvest Quality of Fresh and Canned Clingstone Peaches as Influenced by Genotypes and Maturity at Harvest1
Authors: Kader Adel A. , Heintz Christi M. , Chordas Alexander
Published: August 2022

Large variations in flesh color, firmness, and composition were found among fresh and canned fruits of 8 clingstone peach [Prunus persica (L.) Batsch] genotypes. Flesh color and titratable acidity of fresh fruits were highly correlated with color and sourness of canned fruits, respectively. Sweetness and peach flavor intensity were highly correlated in canned fruits. Genotypic variations in sensory sweetness and peach flavor intensity were not influenced by maturity stage, but variations in sensory sourness and firmness were dependent upon fruit maturity. For all cultivars, picking fruits more mature resulted in higher color and flavor quality of the canned product. Advanced maturity at harvest was accompanied by decreased flesh firmness, green color, and titratable acidity as well as more intense yellow or orange-yellow flesh color, higher carotenoids, ascorbic acid, soluble solids content, and SSC/TA ratio. As much as 42% of the total carotenoids and 95% of the total ascorbic acid were lost during the canning process.
Influence of Mineral Nutrition and Storage on Quality Factors of ‘Jewel’ Sweet Potatoes1
Authors: Hammett Larry K. , Miller Conrad H.
Published: August 2022

‘Jewel’ sweet potatoes [Ipomoea batatas (L.) Lam] were grown for 2 seasons on an Orangeburg loamy sand soil with 3 N sources, 3 K rates, and 2 N rates. NH4NO3 and Ca(NO3)2 were equivalent in influence on root quality at harvest and storage, but NaNO3 significantly reduced root dry matter content. With an increase in N rate from 101 to 202 kgN/ha, weight loss during storage increased and carbohydrate levels, dry matter content, and root intercellular space values decreased. An increase in K applications from 70 to 280 kg/ha reduced root dry matter content.
Characterization of the Light Microclimate in Four Peach Hedgerow Canopies1
Authors: Kappel Frank , Flore J. A. , Layne R. E. C.
Published: August 2022

Light levels were estimated by hemispherical photography at 4 different times during the growing season, in 4 different peach [Prunus persica (L.) Batsch] hedgerow canopies: oblique fan, canted oblique fan, modified central leader, and open center. Greatest percentage of sky levels occurred in the area from above to 25 cm below the top of the canopy. There was little difference between canopy training systems except 1 m above the ground. Hedging improved the light microclimate in the canopies, but only within the top 25 cm. Spectral distribution determined in an open-center tree did not follow the general trend of total radiation. As shading increased, not all wavelengths were absorbed equally, resulting in a decrease of the visible to infrared ratio.
Pollen Morphology of Selected Vitis Cultivars1
Authors: Ahmedullah M.
Published: August 2022

Scanning electron microscopy (SEM) and light microscopy (LM) studies were made on pollen samples of selected cultivars of Vitis labruscana Bailey and V. vinifera. Pollen differed in size, shape, and exine characteristics. The majority of cultivars had tricolporate (3-furrowed) pollen, except “abnormal” types which lacked the furrows (colpi). Based on exine and furrow characteristics, shape, and polar axis/equatorial diameter (P/E) ratios of pollen, cultivars were divided into 3 shape groups. Cultivars with pollen lacking furrows were grouped as “abnormal”. Pollen shape and P/E ratios were better parameters to aid in grape ampelography than exine patterns and furrow characteristics.
Prestorage and Poststorage Starch Levels in Chemically and Hand-defoliated ‘Delicious’ Apple Nursery Stock1
Authors: Abusrewil G. S. , Larsen Fenton E , Fritts Robert
Published: August 2022

To investigate the effects of chemical and hand-defoliation on starch levels in apple nursery stock, 1-year old commercially graded whips of ‘Delicious’ apple (Malus domestica Borkh.) were planted in April 1977 and 1978, headed at 30 cm, and later trained to a single vigorous shoot. Plots were hand-defoliated on October 1, 15, or 30. Additional plots were treated with 1, 2, or 3 applications at 5-day intervals, starting October 5, of 1.5% Dupont WK surfactant (principle functioning agent, trimethylnonylpolyethoxyethanol) alone or plus 20 ppm (2-chloroethyl) phosphonic acid (ethephon). All trees were dug Nov. 15 in both years. Starch levels increased as hand-defoliation was delayed and usually decreased with multiple as compared to single chemical applications. These effects were evident both prestorage and poststorage, with starch levels decreasing during storage in roots and stems but changing little in buds. The amount of shoot growth produced on the trees during the summer following storage and replanting displayed a pattern somewhat like that of the levels of starch in the trees. Delaying hand-defoliation until October 30 produced the highest starch levels (hand- or chemically treated) both years at April planting time.
Desiccation Injury and Direct Freezing Injury to Evergreen Azaleas: A Comparison of Cultivars1
Authors: Rosen Peter M. , Good George L. , Steponkus Peter L.
Published: August 2022

Four cultivars of kurume azalea (Rhododendron sp.), ‘Hersey Red’, ‘Snow’, ‘Coral Bells’ and ‘Hino Crimson’ reported to have different susceptibilities to winter injury in the nursery were compared for their sensitivities to direct freezing injury (both to roots and leaves) and desiccation injury under controlled conditions. Sensitivity to root freezing injury was inversely correlated with winter injury. A positive association between leaf hardiness to freezing injury and resistance to winter injury was found only in ‘Hino Crimson’. Susceptibility to winter injury was most closely associated with desiccation, as indicated by the minimum water potentials under conditions of frozen soil and high evaporative demand.
Pressure Changes in Oxygen-exchanged, Brined Cucumbers1
Authors: Corey K. A. , Pharr D. M. , Fleming H. P.
Published: August 2022

A method was developed for determining internal gas pressure changes of pickling cucumbers (Cucumis sativus L.) during brine storage. Internal pressure decreased by 55 mm Hg during the first hour after the control fruit had been submerged in brine and then gradually increased over the next 2 hours to about the level of atmospheric pressure that had existed immediately after brining. With cucumbers that were gas-exchanged before brining, the pressure decreased by a maximum of 145 mm Hg when O2 was the exchange gas, and increased slightly when N2 was the exchange gas. Pressure changes in O2-exchanged cucumbers corresponded with changes in the level of brine that surrounded the fruit, suggesting that liquid entered the fruit as a consequence of the partial vacuum. O2-exchanged, brined cucumbers acquired a translucent, cured appearance, due apparently to filling of the intercellular gas spaces with liquid. Mechanically induced vacuum failed to induce the cured appearance. Respiratory conversion of O2 to CO2 in control and in O2-exchanged fruit, with greater dissolution of the CO2 than the O2 which it replaced, is thought to account for the partial vacuum that develops in brined cucumbers.
Influence of Calcium Concentration on Peach Seedling Growth and Nutrient Uptake at Low pH1
Authors: Edwards J. H. , Horton B. D.
Published: August 2022

Seedlings of ‘Lovell’ and ‘Elberta’ peach [Prunus persica (L.) Batsch] were grown in the greenhouse for 29 or 50 days in nutrient solutions containing 8, 16, 33, 66, 132, 264, or 660 µM Ca at pH 4.5. Relative growth rate was unaffected by Ca concentrations. Calcium concentration in the stems was increased from 700 to 4330 µg/g dry weight and in the roots from 348 to 1787 µg/g dry weight by Ca treatments for the 29 days of growth. No Ca deficiency symptoms were observed on the seedlings when the Ca concentration in the leaves exceeded 2300 µg/g dry weight. The Ca uptake rates during the 29 days of growth for ‘Lovell’ increased from 0.46 to 3.77 and for ‘Elberta’ from 0.44 to 2.84 µmoles/g fresh-weight-root/day. After 50 days of growth, Ca uptake rates increased for ‘Lovell’ from 0.58 to 3.51 and for ‘Elberta’ from 0.52 to 3.02 µmoles/g fresh-weight-root/day. Calcium accumulated in stems when Ca concentration in the nutrient solution exceeded 264 µm Ca with no change in total Ca content in the roots. The K and P uptake rates were increased by higher Ca treatments but the Mn uptake rate was decreased when the Ca concentration in nutrient solution was greater than 66 µm.
Chilling and Budbreak in Lingonberries, Vaccinium vitis-idaea L.1
Authors: Holloway Patricia S. , Stushnoff Cecil , Wildung David K.
Published: August 2022

Three seedling populations of lingonberries from Fairbanks, Alaska, Oulu, Finland, and the Pasvik River Valley, Norway were exposed to 0, 170, 344, 513, 681, 843, 1013, and 1185 hours of continuous chilling temperatures (4 ± 1°C) to determine chilling requirements necessary to satisfy rest. Both the Finnish and Alaskan populations required at least 681 hours of chilling to obtain maximum terminal vegetative budbreak. Continuous chilling for 1185 hours was insufficient to obtain maximum budbreak in the Norwegian population. In the Finnish and Alaskan populations neither the percentage of stems exhibiting lateral budbreak nor the number of lateral branches per stem differed among chilling treatments. Plants from Norway showed significantly greater lateral budbreak in the 513- and 681-hour treatments than in all other treatments. At least 681 hours of chilling were necessary to achieve normal flowering in the Finnish population.
Effect of Plant Population and Planting Date on Root and Starch Production of Buffalo Gourd Grown as an Annual1
Authors: Nelson J. M. , Scheerens J. C. , Berry J. W. , Bemis W. P.
Published: August 2022

The buffalo gourd (Cucurbita foetidissima HBK) produced root yields as high as 34,550 kg/ha with a root starch content of 63.5% on a dry weight basis at a 920-m elevation site. A quadratic relation between root yield and plant population showed maximum yield at 550,000 plants/ha. No clear relation was observed between root starch content and plant population. An April planting resulted in higher root and starch yields than a July planting, at a 370-m elevation site. Vine growth appeared to be restricted when maximum air temperatures were above 40°C.
Growth Changes of Apple Seedlings in Response to Simulated Acid Rain1,2
Authors: Forsline Philip L. , Dee Robert J. , Melious Richard E.
Published: August 2022

In a greenhouse experiment, Malus hupehensis (Pamp.) Rehd. seedlings were treated weekly with simulated acid rain solutions ranging from pH 2.25 to pH 7.0. Necrotic lesions developed on leaves at pH 2.25 and pH 2.50 immediately after the first application at the 8-node stage. Following the 9th weekly application on seedlings with 23 to 26 nodes, lesions developed at pH levels up to 3.25. At final destructive harvest, 20% of the leaf area at pH 2.25 and 8% of the leaf area at pH 2.50 was injured. Significant growth reduction occurred at these 2 pH levels. Regression analysis indicated extensive growth inhibition at <pH 3.0, no growth inhibition around pH 3.5, some inhibition between pH 4.5 and pH 5.6, and normal growth at pH 7.0 in comparison to the unsprayed control. Growth was negatively correlated with lesion formation at 3 destructive harvest dates. Relative growth rates were reduced only at pH 2.25 and pH 2.50 and reduction in the unit leaf rate was also observed. Lesion development continued to increase on the basal leaves through the 6th weekly application but leveled off during the final applications. Negative correlations of photosynthesis rate to lesion percentage and dry weight to lesion percentage were observed.
Alteration of Growth, Exudation Rate, and Endogenous Hormone Profiles in Mechanically Dwarfed Sunflower1
Authors: Beyl Caula A. , Mitchell Cary A.
Published: August 2022

Growth in stem length, shoot fresh weight, and leaf surface area of sunflower (Helianthus annuus L.) plants was inhibited by periodic shaking (seismo-stress) or rubbing (thigmo-stress), and by drought-stress treatments. Mechanical- and drought-stress treatment of intact plants reduced xylem exudation from detopped plants. This reduction was accompanied by a reduction in root dry weight only in the case of the drought-stress treatment. Exudate from thigmo-stressed plants contained a broad band of extractable inhibitors some of which co-chromatographed with abscisic acid (ABA). ABA-like substances were not detected in exudate from tall or dwarf controls. Enhanced cytokinin (CK)-like substances were detected in exudate collected from seismo-stressed plants. Shoot tip extracts from thigmostressed plants contained no detectable gibberellin (GA)-like substances, whereas those extracts from unstressed controls contained multiple zones of GA-like activity. Extracts of plant parts most disturbed by a given mechanical treatment yielded no detectable GA-like substances. This study provides evidence that, in addition to auxin and ethylene, other endogenous hormones, particularly GA-like substances, are influenced by mechanical stress in sunflower.
Cultivar Identification in Camellia japonica L. using Allozyme Polymorphisms1
Authors: Wendel J. F. , Parks C. R.
Published: August 2022

Allozyme variation at 15 loci resolved from 12 enzyme systems was studied in 205 accessions of cultivated Camellia japonica. All loci were polymorphic and a total of 64 alleles were detected. The sensitivity of electrophoresis in distinguishing clones was high, with 95.4% of the clones uniquely characterized by their 15-locus genotypes. Replicates of cultivars collected in different localities were allozymically identical. The hypothesis that some cultivars originated as sports was tested in a number of cultivar groups. The allozyme data failed to support this hypothesis for some groups, suggesting that in these cases cultivars of independent origin have become incorrectly incorporated into bonafide clone groups during their long history of cultivation.
Vacuum Fumigation with Ethyl Formate to Control the Green Peach Aphid in Packaged Head Lettuce1
Authors: Stewart Joseph K. , Aharoni Yair
Published: August 2022

Vacuum fumigation for 2 hours with 0.5, 1.0, or 1.5% ethyl formate (EF) killed 93–97% of the green peach aphids [Myzus persicae (Sulzer)] in film-wrapped, packed head lettuce (Lactuca sativa L.). EF at 0.5% did not injure the lettuce, but 1.0 or 1.5% EF injured 30 and 97% of the heads, respectively. Regardless of the EF dosage used, about 75% of the fumigant was sorbed by the lettuce within 1 hour. A 1-hour vacuum fumigation using 0.5% EF appears to be optimal to control the green peach aphid in film-wrapped, packed lettuce.
The Relationship Between Ethephon and Auxin on Adventitious Root Initiation in Cuttings of Vigna radiata (L.) R. Wilcz1
Authors: Geneve Robert L. , Heuser Charles W.
Published: August 2022

Adventitious root initiation decreased in ‘Berken’ mung bean cuttings treated with ≥ 10−4 m (2-chloroethyl) phosphonic acid (ethephon). Ethephon at 10−3 but not 10−5 m reduced root length and caused a redistribution of roots along the hypocotyl. The application of ethephon in combination with indoleacetic acid (IAA), indolebutyric acid (IBA), naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D) reduced root initiation. An initial treatment of ethephon followed by NAA, or NAA followed by ethephon, inhibited root initiation to the same degree. Ethephon—whether applied at the time of cutting preparation or up to 12 hours later—inhibited root initiation to the same extent.
Association of Calyx Green End Disorder of ‘Golden Delicious’ Apples with Tissue Fluoride1
Authors: Barritt Bruce H. , Kammereck R.
Published: August 2022

Calyx green end disorder (GED) of ‘Golden Delicious’ apple (Malus domestica Borkh.) is a sublethal fruit disorder characterized by a flattening distortion of the calyx lobes and a persistent green coloring of the skin at the calyx end of mature fruit. The severity of the symptom varied from mild skin greening to necrosis and was subjectively evaluated on a scale of one to 5. Fluoride applied as ammonium fluoride to spur leaves, fruit, the whole canopy, and via xylem caused symptoms identical to those in an untreated commercial orchard with a serious GED problem. Increasing severity of GED up to a rating of 3 was associated with increased levels of F in cortical calyx fruit tissue (r = 0.93). In the commercial orchard, the incidence of GED was associated with elevated levels of soil- and air-borne F. Season-long calcium chloride sprays were not effective in reducing GED, but weekly overhead irrigation rinsing treatments did significantly reduce GED severity. Gibberellins A4 + 7 (GA4 + 7) plus 6-benzylamino purine (BA) applied at bloom also reduced severity of GED but, in combination with irrigation rinsing, was no more effective than rinsing alone.
Freezing of Water in Citrus Leaves
Authors: Anderson J.A. , Gusta L.V. , Buchanan D.W. , Burke M.J.
Published: August 2022

Leaves of cold-acclimated lemon [Citrus limon (L.) Burm. f.], grapefruit (C. paradisi Macf.), orange [C. sinensis (L.) Osbeck], and mandarin (C. unshiu Marc.) trees ranged in cold hardiness from −4 to −11°C. No significant differences in water content (g H2O/g dry weight) or melting point depression were observed. Plots of liquid water content during freezing (g H2O/g dry weight) vs. temperature were similar for the 4 citrus species. The tissues apparently deviated from ideal freezing behavior because less ice was formed. The reduced ice formation could not be accounted for by osmotic effects. Negative pressure potential developed during freezing is hypothesized to play a role in tissue water potential in frozen systems. It was concluded that hardier Citrus leaves survive freezing of a larger fraction of their tissue water.
Mineral Nutrient Status of ‘Convexa’ Holly Cuttings during Intermittent Mist Propagation as Influenced by Exogenous Auxin Application
Authors: Blazich Frank A. , Wright Robert D. , Schaffer Henry E.
Published: August 2022

Hardwood stem cuttings of Ilex crenata Thunb. ‘Convexa’, treated with and without indolebutyric acid (IBA), were inserted into a perlite rooting medium and misted with deionized water during intermittent mist propagation in a controlled-environment chamber. Initially, and at weekly intervals for 6 weeks, leaves, upper stems (portion of stem above rooting medium), and lower stems (portion of stem in rooting medium) were analyzed for N, P, K, Ca, and Mg. At the conclusion of the study, both nontreated and IBA-treated cuttings showed a slight increase in dry weight with detectable but slight leaching of N and K and no detectable leaching of P, Ca, and Mg. Mineral nutrient mobilization to the lower stem was not detected during root initiation for nontreated and IBA-treated cuttings. Following root initiation and later budbreak on the upper stem, N, P, K, Ca, and Mg were all mobililized from the leaves of nontreated and IBA-treated cuttings to the upper stem, whereas only N, P, and K were mobilized to the lower stem of IBA-treated cuttings. For nontreated cuttings, all nutrients were mobilized from the lower stem to the upper stem, while for IBA-treated cuttings only Ca and Mg were mobilized from the lower stem to the upper stem. Root development as influenced by IBA treatment and budbreak on the upper stem had a strong influence on mineral nutrient mobilization.
Effects of the Basal Medium on Growth of Immature Tomato Embryos in Vitro
Authors: Neal Catherine A. , Topoleski Leonard D.
Published: August 2022

Embryos of tomato (Lycopersicon esculentum Mill.) were excised 15 days after pollination and cultured on 20 different media to test a broad range of concentrations of salts, sucrose, and organic supplements on growth and development. Embryo growth and morphological development on 6 of the experimental media were better than on Murashige and Skoog’s (1962) revised tissue culture medium. Salt and sucrose levels were significant in their effects on growth, as was the interaction of salts with vitamins and amino acids. The medium with high salts, high sucrose, and low vitamins and amino acids was superior to any of the other treatments.
Cherry Fruit Growth: Localization of Indoleacetic Acid Oxidase and Inhibitors in the Seed
Authors: Valpuesta Victoriano , Bukovac Martin J.
Published: August 2022

The distribution of indoleacetic acid (IAA) oxidase activity was determined in seeds of sour cherry (Prunus cerasus L. cv. Montmorency) fruits in mid-Stage II of development, 32 days after full bloom. The greatest activity was found in the integument tissue. No IAA oxidase activity was detected in the embryo or endosperm. When polyvinylpolypyrrolidone (PVP) was added to the extraction buffer (0.2 m acetate, pH 4.0), a trace of activity was detected in the embryo, but not in the endosperm. Inhibitors of IAA oxidase were coextracted with the enzyme and occurred in the greatest quantity in the integument tissue, an intermediate level in the embryo, and only a trace in the endosperm. The inhibitor from the integument and embryo tissues exhibited different kinetics when increasing concentrations were assayed against IAA oxidase isolated from the integuments. The possible significance of IAA oxidase and inhibitor distribution in the seed is discussed in relation to sour cherry fruit growth.
Effects of Anaerobic Nitrogen and Carbon Dioxide Atmospheres on Ethanol Production and Postharvest Quality of ‘Carlos’ Grapes
Authors: Saltveit Mikal E. , Ballinger Walter E.
Published: August 2022

The ethanol concentration of ‘Carlos’ grapes (Vitis rotundifolia Michx.) increased linearly with time (1 to 4 hours) and exponentially with temperature (0° to 30°C) during exposure to an anaerobic N2 or CO2 atmosphere. Ethanol loss from grapes placed in air after 4 hours in CO2 was dependent on the concentration of ethanol accumulated during anaerobiosis. Fruit quality was unaffected by 0° exposure to an anaerobic CO2 atmosphere for up to 72 hours after 6 hours in CO2 at 30°. However, 30 hours in a CO2 atmosphere at 30° reduced fruit quality. An equation was derived to calculate ethanol accumulation during cooling of warm fruit under anaerobic atmospheres.
Rapid and Specific Staining for Routes of Liquid Entry into Cucumber Fruit
Authors: Daeschel M.A. , Fleming H.P.
Published: August 2022

A procedure is described for studying routes of liquid entry into and movement within pickling cucumber fruit (Cucumis sativus L. cv. Chipper). The internal gases of the fruit are exchanged with oxygen in a closed container. Fruit are then covered with 0.5% aqueous safranin O and allowed to stand for a few hours. Liquid was shown to enter the fruit through epidermal regions of greatest stomatal density, which are near placental tissue. The dye solution then moved through intercellular spaces and cell walls of placental and other mesocarp tissues and vascular elements. The stain facilitated delineation of stomata and visual observation of routes of liquid movement. Liquid entrance apparently is induced due to a partial vacuum created within the O2-exchanged and liquid-submerged fruit.
The Relationship of Radicle Length to Chilling Sensitivity of Pregerminated Pepper Seed
Authors: Irwin Christine Cayer , Price Hugh C.
Published: August 2022

Seeds of pepper (Capsicum annuum cv. Staddon’s Select) with radicles from 0 to 8.6 mm in length were examined for their sensitivity to 0°C exposure by means of a low temperature emergence assay. If seeds were unchilled, radicle length and time to 50% emergence were inversely related. After 4 days at 0°, seeds with long radicles emerged as slowly as seeds with short radicles. Percent emergence after 4 days at 0° was greatly reduced for seeds with long radicles. Seeds with long radicles had a higher rate of respiration and a lower amount of glucose equivalents than seeds with short radicles. The faster depletion of food reserves in seeds with long radicles may contribute to their slowed emergence in cold soil.
Relationships of Parental Combining Ability and Testcross Segregation to Breeding Productivity in Tomato
Authors: Peirce L.C.
Published: August 2022

Crosses between 6 inbreds of tomato (Lycopersicon esculentum Mill.) and each of 2 hybrid testers, and progenies derived from them by single seed descent (SSD), were grown in replicated trials in 1980 and 1981. Early yield, total yield, and fruit size means of the inbred parents were found to be correlated with estimates of general combining ability (GCA); strong relationships also were found among midparent, GCA, and testcross means and means of SSD derived lines. These relationships were especially evident for fruit size, a trait of moderately high heritability. GCA was correlated with progeny segregation for fruit size and for early yield; but only for fruit size was a significant correlation found between testcross segregation and similar data for SSD progenies.
The Influence of Environment on Apple Tree Growth, Leaf Wax Formation, and Foliar Absorption
Authors: Darnell Rebecca L. , Ferree David C.
Published: August 2022

The influence of environmental conditions on tree growth and cuticular covering of leaves of apple (Malus domestica Borkh.) was investigated in relation to spary uptake. Various interactions between environmental factors influenced growth responses. Under cooler temperatures (20°C), 75% shade reduced shoot growth and leaf number; however, under warmer temperatures (25°), shading had no effect. High soil water potential (−13 KPa) and 75% shade significantly reduced total leaf area per tree, while under low soil water potential (−33 KPa), shading had little effect. The dry weight of total leaves per tree decreased 46% as soil water potential decreased under full-sun conditions. Under shade, a decrease in soil water potential resulted in a 20% decrease in dry weight. Total stem dry weight decreased as temperature increased under full-sun conditions; however, temperature had little effect on stem dry weight in plants grown under shade. Under 75% shade, an increase in temperature decreased total specific leaf weight (SLW), while under full sun there was no temperature effect. SLW of newly formed leaves was not influenced by environmental interactions. Leaf epicuticular wax quantity increased as soil water potential decreased. A decrease in soil water potential increased the proportion of alkanes and wax esters in extracted leaf waxes. Alkane content also increased as temperature increased. The different environmental growing conditions influenced the photosynthetic mechanism and masked the effect of prometryn, a triazine herbicide, thereby rendering it unreliable as a method for determining foliar absorption.
Response of Grapevines to Fluoride under Field Conditions
Authors: Murray Frank
Published: August 2022

Grapevines (Vitis vinifera L. cv. Shiraz) were fumigated in open-top chambers with hydrogen fluoride for 64 days at mean atmospheric fluoride concentrations of 0.17 or 0.28 μgHFm-3. Other grapevines grown under ambient conditions in the vineyard or maintained in control chambers were exposed to 0.13 or 0.05 μgHFm-3, respectively. Leaves of grapevines exposed to 0.28, 0.17, 0.13, or 0.05 μgHFm-3 accumulated up to 85, 55, 20, or 11 μgFg-1, respectively. Foliar necrosis was observed on plants exposed to 0.28 μgHFm-3, but no injury symptoms were observed at 0.17 μgHFm-3 or in control plants. Grapevines growing under ambient conditions had significantly greater mean bunch weight, peduncle weight, number of grapes per bunch, and leaf protein levels than the fumigated treatments. However, these differences may be associated with a chamber effect rather than with an effect of fluoride on grapevines. No significant differences were found between treatments for grape potential alcohol content, fruit acids, number of bunches or grapes per vine, fresh weight of grapes, or leaf chlorophyll content, despite foliar fluoride concentrations in the highest fluoride fumigation level reaching 85 μgFg-1. No evidence was found of significant fluoride accumulation in berries or canes.
Storage Responses of Four Apple Cultivars to a “Rapid CA” Procedure in Commercial Controlled-atmosphere Facilities
Authors: Lau O.L.
Published: August 2022

Commercial applications of a “rapid CA” procedure (short loading time and rapid reduction of storage O2 to 2.5%) significantly improved retention of flesh firmness and juice acidity in controlled-atmosphere (CA)-stored apples from a wide range of production regimes. ‘Golden Delicious’ and ‘McIntosh’ apples responded more to the rapid CA procedure than did ‘Spartan’ or ‘Delicious’ apples. Rapid CA maintained fruit firmness of ‘Golden Delicious’ and ‘Spartan’ apples picked over a wide range of maturities and reduced the susceptibility of ‘Golden Delicious’ apples to bruising.
Ammonium Adsorption on a Pine-bark Growing Medium
Authors: Foster W.J. , Wright R.D. , Alley M.M. , Yeager T.H.
Published: August 2022

Pine bark was shown to adsorb 1.5 mg of N/g of bark when NH4 solutions were leached through the bark. Increasing pH of bark increased adsorbed NH4. At pH 3.3, only NH4 was adsorbed to bark particles when a fertilizer solution containing NH4, Ca, K, and Mg was applied. However, adsorption of NH4 and other cations increased as pH was increased from 3.8 to 5.8. These data indicate that 2 types of sites exist for the adsorption of NH4 to pine bark. One site is effective at lower pH; the other is active as pH increases. Daily application of 2.5 cm of water containing 50 ppm NH4 required 20 days for equilibration to occur so as to satisfy all binding sites. Thus, incorporation of NH4 into a pine-bark medium prior to planting may be advisable to prevent low N levels from occurring in the container solution due to NH4 binding when plants are first planted and fertilized.
Net CO2 Assimilation Characteristics of Walnut Leaves under Field and Laboratory Conditions
Authors: Tombesi A. , DeJong T.M. , Ryugo K.
Published: August 2022

The CO2 assimilation characteristics of walnut leaves (Juglans regia L.) were measured on excised branches using controlled, open-system, infrared gas analysis techniques in the laboratory and on large bearing trees with a CO2 depletion method in the field. The mean maximum rate of net CO2 assimilation measured by both techniques was 1.3 nM CO2 cm-2s-l on a leaf area basis of 6.0 nm CO2 mg N-1s-1 on a leaf nitrogen basis. Leaves approached light saturation at 600-800 µEs-1m-2, and exhibited an otpimum range for CO2 assimilation at 18 to 26°C. CO2 assimilation increased linearly with increases in intercellular CO2 concentrations between 60-250 µl liter-1. The daily pattern of field CO2 assimilation was highly correlated with leaf conductance to H2O but exhibited a midday depression that was independent of the daily pattern of incident photosynthetic photon flux density at the surface of the leaves.
Inflorescence and Floral Development in Pelargonium X hortorum
Authors: Wetzstein Hazel Y. , Armitage Allan
Published: August 2022

Floral initiation and development in the hybrid geranium, Pelargonium X hortorum Bailey, were examined using scanning electron microscopy. Inflorescence initiation was marked by a raising of the apex followed by the formation of convex flower primordia. In floral development, 5 sepal primordia were delimited, closely followed by 5 petal primordia. Imbricate sepals enclosed the floral apex during later developmental stages. Five antesepalous, then 5 antepetalous stamen primordia were initiated. Five gynoecial primordia arose, forming a pentagonal ridge, carpellary lobes, and eventually an elongate style with stigma. Three of the antepetalous stamen primordia developed into filaform starninodia.
Seasonal Changes in Specific Leaf Weight, Net Photosynthesis, and Chlorophyll Content of Peach Leaves as Affected by Light Penetration and Canopy Position
Authors: Marini Richard P. , Choma Marini Michele
Published: August 2022

Diffuse photon flux density of photosynthetically active radiation (PAR) was measured throughout the season in peach trees [Prunus persica (L.) Batsch. cv. Harken] trained to an open center. Penetration of PAR generally decreased as shoot extension continued through the season. PAR was greater at the tree periphery and center than midway between the 2 points. PAR also decreased from the upper levels to the lower levels of the tree canopy. Specific leaf weight (SLW) at all positions increased from early June until August. SLW generally followed the same pattern as PAR, with lowest SLW developing midway between the tree periphery and center. Net photosynthesis (Pn) was greatest for peripheral leaves, lowest for leaves midway into the tree, and intermediate for leaves from the tree center. Pn and SLW were linearly correlated. Leaves developing at different distances from the tree center had similar stomatal resistances. There was no consistent influence of canopy position on chlorophyll content, but interior leaves tended to have greater chlorophyll content than peripheral leaves.
Influence of Time of Summer Pruning and Limb Orientation on Growth and Flowering of Vigorous ‘Delicious’ Apple Trees
Authors: Myers S.C. , Ferree D.C.
Published: August 2022

Trees of apple [Malus domestica Borkh. cv. Red Prince Delicious/Malling (M) 9] planted in 1974 on a 1.52 x 3.05 m spacing exceeded the allotted space by 40% at the initiation of the study in 1979. Trees were unpruned (control) and pruned on July 3, August 3, or September 3 in 1979 and 1980. Pruning decreased limb and trunk cross-sectional area. Horizontal limb cross-sectional area increase was less than that of vertical limbs. Pruning increased spur leaf numbers, area, and size on the 1978 limb section but only July and August pruning prevented the decline in spur numbers occurring on control limbs. July pruning increased bloom per cluster but decreased total bloom on the 1978 limb sections. August and September pruning were most efficient in maintaining tree height while all pruning treatments maintained tree spread.
Effects of Dormant and Summer Pruning, Disbudding, and Growth Retardants on Growth, Flower Bud Formation, and Fruiting of Young Apple Trees
Authors: Mika Augustyn , Grochowska Maria J. , Karaszewska Alicja , Williams Max W.
Published: August 2022

Summer pruning, dormant pruning, and growth-regulator treatments were applied for 5 years on newly planted ‘McIntosh’ and ‘Melba’ apple trees (Malus domestica Borkh.) on Alnarp 2 and Mailing 26 rootstocks. All forms of pruning reduced tree growth and yield. Light-to-moderate pruning was the best treatment for forming tree canopies. The reported stimulative effect of summer pruning on flower bud formation was not supported by this research. Pinching shoot tips led to a new secondary growth and inhibited rather than stimulated flower bud formation.
Relationship of Daily Growth and Development of Peach Leaves and Fruit to Environmental Factors
Authors: Haun Joseph R. , Coston D.C.
Published: August 2022

A procedure was developed for detecting daily changes in the rate of growth and development of leaves and fruit of peach [Prunus persica (L.) Batsch.]. Quantitative morphological stages of leaf and fruit development were determined for 3 cultivars, transformed into growth rates, and used as dependent variables for regression on a variety of daily environmental variables: maximum and minimum temperature, degree hours, precipitation, solar radiation, estimated soil moisture (Thornthwaite method), 1- to 3-day lags of these variables, quadratic and cubic transformations, and selected 2-variable products of the basic variables. Prediction equations performed well in tests from different years, locations, and cultivars. Maximum and minimum temperature, precipitation, soil moisture, and age were the most important variables for the leaf growth prediction equation. In the fruit growth prediction equation, maximum and minimum temperature, soil moisture, and age were most important.
The Use of Temporary Trees in a Hedgerow Planting of Peach Trees
Authors: Mitchell P.D. , Chalmers D.J. , van Heek L.A.G.
Published: August 2022

Hardwood cuttings of peach [Prunus persica (L.) Batsch] were taken in July and planted in November at 2 levels of spacing (2 x 1 m and 4 x 1 m). Alternate rows at the 2 x 1 m spacing were considered to be temporary and pruned to minimize competition with the permanent trees. All trees cropped in 2nd leaf. Individual trees at 2 x 1 m were more fruitful and yielded 19 MT ha-1 of canning size fruit compared to 7 MT ha-1 from the 4 x 1 m planting. In 3rd and 4th leaf, the permanent trees at the 2 x 1 m spacing continued to be more fruitful than their 4 x 1 m counterparts. By the 5th leaf, however, yield per tree was greater at the 4 x 1 m spacing. Results show that the temporary trees should have been removed prior to 5th leaf before severe pruning of the permanent trees became necessary.
Prediction of Sweet Corn Field Emergence by Conductivity and Cold Tests
Authors: Waters Luther , Blanchette Bonnie L.
Published: August 2022

Field-emergence trials and laboratory seed-quality tests were conducted on 45 seed lots of 13 sweet corn (Zea mays L.) hybrids. Results from standard laboratory germination tests were not correlated with field emergence in 4 field trials. Cold tests conducted in sterile sand and on rolled towels were correlated highly with field emergence. Electrolyte leakage tests conducted on individual seeds with the ASA-610 Automatic Seed Analyzer were superior to bulk-seed measurements with a conductivity meter. By combining the seedling-growth cold test (total seedling dry weight) with the Automatic Seed Analyzer test, multiple correlation values with field emergence ranged from 0.70 to 0.80.