bluuebunny/crossref_metadata_2025 huggingface dataset:
Elemental Composition of Fresh Strawberry Fruit1
Authors: Albregts E. E. , Howard C. M.
Published: August 2022

Fruit and calyx of four strawberry clones (Fragaria × ananassa Duch.) were analyzed for N, P, K, Ca, Mg, Fe, Zn, Mn, B, and Cu content for 2 seasons. The elemental concn varied because of the year, the clone, and the time of season. The concn of the elements in the fruit decreased in the following order: K, N, P, Ca, Mg, Fe, B, Mn, Zn, and Cu. The elemental concn was greater in the calyx than in the fruit; probably as a result of the much higher dry weight content of the calyx. The total elemental content in kg/ha of the fruit and calyx for a season ranged as follows: K from 40 to 67, N from 33 to 49, P from 6 to 9, Ca from 5.4 to 7.5, Mg from 3.7 to 5.7, Fe from 0.11 to 0.15, Mn from 0.05 to 0.10, B from 0.04 to 0.09, Zn from 0.04 to 0.06, and Cu from 0.012 to 0.016.
Determination of Irrigation and Fertilizer Practices for Jade Plant [Crassula argentea (L.) Thunb.]1
Authors: Spooner J. , Daley L. , Ware G. , Vines M.
Published: August 2022

Daily watering gave increased growth of jade plants over weekly watering if fertilizer was applied. The optimum fertilizer rate with either weekly or daily watering was calculated as 100 ml of 250 ppm N of a 20N:8.6 P:16.6K fertilizer per 10 cm pot.
Respiration and Ethylene Production in Mammee Apple (Mammea americana L.)1
Authors: Akamine Ernest K. , Goo Theodore
Published: August 2022

Gas chromatography and bioassays were used to identify ethylene (C2H4) in fruit emanations of mammee apple (Mammea americana L.). C2H4 production probably triggered the respiratory rise in preclimacteric fruit and its relationship to respiration was typical of that for a climacteric fruit. C2H4 production was however, independent of respiration in immature and postclimacteric fruits. C2H4 production increased to a peak and then declined with deterioration of fruit in spite of nearly constant rates of respiration in immature fruit and declining rates in postclimacteric fruit. Peak production of C2H4, 408 μl per kg per hr, from preclimacteric fruit is probably the highest reported among fruits.
Variability in Noninfectious Bud-failure of ‘Nonpareil’ Almond. I. Location and Environment1
Authors: Kester Dale E. , Asay R. N.
Published: August 2022

The incidence of noninfectious bud-failure (BF) in ‘Nonpareil’ almond (Prunus amygdalus Batsch) trees propagated from a single source tree increased continuously with time at different rates in different orchards. Development was fastest and symptom expression was most severe in areas with the highest summer temperatures. BF-potential (susceptibility) could be modified by nursery conditions, although only to a minor degree compared with the effect of orchard location. Symptomless can be converted to BF by shifting from a low to a high-temperature regime. A reverse shift gave no reversion in BF-potential, but symptoms may not be expressed at a low-temperature location.
Bud Opening of Gypsophila paniculata L. cv. Perfecta with Physan-201
Authors: Farnham D. S. , Kofranek A. M. , Kubota J.
Published: August 2022

A 200 ppm solution of Physan-20 [Active ingredients: n-alkyl (60% C14, 30% C16, 5% C12, 5% C18) dimethyl benzyl ammonium chlorides, 10%; n-alkyl (68% C12, 32% C14) dimethyl ethylbenzyl ammonium chlorides, 10%; inert ingredients, 80%.] was as effective in opening buds of ‘Perfecta’ gypsophila as was a 25 ppm silver nitrate solution when combined with sucrose. Sucrose (10%) was more effective in a short time period than 5% in combination with Physan-20. The minimum time in the solution for producing high quality blooms was 4 days. Physan-20, a quaternary ammonium compound, effectively opened gypsophila buds in tap water moderately high in salts, bicarbonates and nitrates. Physan-20 offers an effective alternate to silver nitrate for opening gypsophila without deionized water.
Promotion of Softening Processes in Pear by Acetaldehyde, Independent of Ethylene Action1
Authors: Janes Harry W. , Frenkel Chaim
Published: August 2022

Acetaldehyde is produced in fruit of pear (Pyrus communis L.) and can stimulate ripening. The action of selective inhibitors indicates that acetaldehyde operates independently of ethylene.
Nitrate and Nitrite Levels in Fresh Spinach as Influenced by Postharvest Temperatures1
Authors: Aworh Ogugua C. , Brecht Patrick E. , Minotti Peter L.
Published: August 2022

Various postharvest temperature-time combinations on nitrate-nitrite conversion in fresh spinach (Spinacia oleracea L.) were investigated. At 0°C spinach could be held as long as 40 days without significant changes in these nitrogen components. Substantial loss of nitrate-N and accumulation of nitrite-N occurred in spinach held for 3 to 7 days at 20°. Simulated transit periods of 2 weeks at 0 and 5° and simulated marketing periods of 3 days at 10° were imposed separately and in sequence to spinach in pretransit storage for 15 hours at 21° or to spinach without a pretransit storage period. Accumulations of nitrite-N exceeding 2 ppm fresh weight were found only if the simulated transit period was 5°. In this instance pre- and posttransit storage further increased nitrite accumulation. Nitrite-N levels exceeding 10 ppm were found only in visibly decayed samples.
Influence of plant spacing on yield of muscadine grape
Authors: Brightwell W. T. , Austin M. E.
Published: August 2022

In the paper entitled, Influence of plant spacing on yield of muscadine grape by W. T. Brightwell and M. E. Austin (J. Amer. Soc. Hort. Sci. 100(4):374-376, 1975), the figure in Table 2, Year 1955, 20.1 square meters, 435 plants/ha should read 9.8a instead of 26.8a and the avg for the same column should read 29.0ab instead of 29.6ab.
Soil Preparation Effects on Compaction, Carrot Yield, and Root Characteristics in Organic Soil1
Authors: White J. M.
Published: August 2022

Rolling organic soil after plowing and drag disking resulted in significantly lower marketable yields, more forks (branching) and less stubbed (premature blunting resulting in an unmarketable root) carrots (Daucus carota L.) than not rolling. Using a rotary tiller before bedding had no significant effect on yield or other characteristics measured. Bed making with a tilrovator or bed shaper did not significantly affect yield, root length, number of forked, crooked or split carrot roots. Compaction, as measured with a penetrometer, did not have a linear relationship between the eight tillage treatments used in preparing beds and any of the root characteristics measured such as yield, length or number of misshapen roots.
Cold Hardening ‘Valencia’ Orange Trees to Tolerate −6.7°C Without Injury1
Authors: Yelenosky G.
Published: August 2022

Potted citrus trees, 1-yr-old ‘Valencia’ orange (Citrus sinensis (L.) Osbeck) on 1.5-yr-old Rusk citrange (C. sinensis (L.) Osbeck × Poncirus trifoliata) rootstocks were maintained for 6 consecutive 7-day periods in a controlled environment to induce cold hardiness with cold-hardening temperatures 10 ± 1°C, illumination 500 μeinsteins/m2 per sec (photosynthetically active radiation = PAR), relative humidity, 60 ± 5%. Trees progressively cold hardened as a result of the above conditions and, after 5 weeks, would tolerate −6.7° for 4 hours without apparent injury. Leaves sustained injury up to 5 weeks and stems up to 3 weeks of cold hardening. Solutes increased most rapidly in leaves during the first week as a result of carbohydrate accumulation.

Proline, glutamic acid and valine increased, whereas other amino acids decreased. Water potentials in the leaves of hardened trees averaged −19.5 bars after 6 weeks of cold hardening compared to −5 bars in leaves of unhardened trees.
Growth and Development of Highbush Blueberry. II. Reproductive Growth, Histological Studies1
Authors: Gough R. E. , Shutak V. G. , Hauke R. L.
Published: August 2022

Flower bud ontogeny was similar in plants of high bush blueberry (Viccinium corymbosum Ait.) grown under normal conditions and under treatment with 5000 ppm succinic acid-2,2-dimethylhydrazide (daminozide) sprays.
Ozone Susceptibility of Ten Azalea Cultivars as Related to Stomatal Frequency or Conductance1
Authors: Gesalman C. M. , Davis D. D.
Published: August 2022

Ten cultivars of azalea (Rhododendron sp.) were exposed to 0.30 ± 0.05 ppm ozone (590 ±100 μg/m3) for 8 hours at various times during the summer. ‘Louise Gable,’ ‘Delaware Valley White’ and ‘Rose Greeley’ were significantly more susceptible than were ‘Stewartstonian,’ ‘Fedora,’ ‘Orange Beauty,’ ‘Hino-crimson,’ ‘Hershey Pink,’ ‘Rosebud,’ and ‘Springfield Crimson.’ Neither rate of gas exchange nor stomatal frequency was correlated with degree of visible injury induced by ozone.
Pollination Effects on Fruit and Seed Development in ‘Comice’ Pear1
Authors: Callan Nancy W. , Lombard Porter B.
Published: August 2022

Cross-pollination increased fruit set, fruit size and seed content of ‘Cornice’ pear (Pyrus communis L.) in 3 large orchards without pollenizers. Supplemental self-pollination was equivalent to open pollination in its effect on fruit set and size. Low female fertility of ‘Comice’ could not be accounted for by early ovule degeneration or frost injury. Pollen transfer by bees was observed to be low in 2 orchards, with 36 and 41% of seedless fruit the result of open pollination. In comparison, only 6% of open-pollinated fruit were seedless in the orchard of greatest bee activity. Seedlessness was due to seed abortion during early fruit development. Classification of aborted seeds as to size at time of abortion revealed that in most fruits a minimal amount of seed growth occurs, although fruit retention does not require the presence of fully developed seeds. Fruit size was positively correlated with seed content, although this relationship was less pronounced in fruits with high seed count. The importance of seed development before abortion and of fully developed seeds in fruit set as well as fruit size is shown.
Distinguishing Rose Cultivars by Polyacrylamide Gel Electrophoresis. II. Isoenzyme Variation Among Cultivars1
Authors: Kuhns Larry J. , Fretz Thomas A.
Published: August 2022

Protein and active enzymes were extracted from leaves of 8 rose cultivars. Extracts were run on polyacrylamide gels and stained for total protein, peroxidase, esterase, malate dehydrogenase, cytochrome oxidase, phenoloxidase, and polyphenoloxidase. Three leaf positions on each cultivar were sampled in an attempt to determine a sampling standard. Because of differences in growth habit among the cultivars, and different optimum locations for the enzymes, a standard location could not be set. Banding data were tabulated and used to prepare coefficient of similarity values and flow charts showing separations. All cultivars could be distinguished by differences in their enzyme banding patterns if results from several systems were employed.
Comparative Crossability of 4 Diploid Vaccinium Species1
Authors: Ballington James R. , Galletta Gene J.
Published: August 2022

The comparative self-compatibility, intra-, and interspecific crossability of representative clones of V. atrococcum (Gray) Heller, V. caesariense Mackenzie, V. darrowi Camp, and V. tenellum Aiton was determined. The number of germinated seeds and number of vigorous seedlings proved to be the best criteria for evaluation of crossability. The 4 species were largely self-incompatible. Generally, intraspecific and interspecific crossability levels were singificantly higher than those of the self-pollinations. Interspecific crossability was significantly lower than intraspecific crossability. Crossability levels within species and the range in crossability in individual combinations among species were extremely variable. Although F1 hybrids were produced in each of the 6 species hybridizations attempted, the rate of success was highly variable, and the direction in which the cross was made was usually critical. Specific combining ability was considerably more important than general combining ability in achieving species hybridizations. The hypothesis of complete homoploid interfertility in Vaccinium was not valid for these 4 species. The ranking of species crossability (number of vigorous seedlings per 100 pollinations) from highest to lowest was: V. atrococcum – V. caesariense, V. atrococcum – V. darrowi, V. darrowi – V. tenellum, V. caesariense – V. tenellum, V. caesariense – V. darrowi, and V. atrococcum – V. tenellum.
Xylem Water Potential and Electrical Impedance Ratios as Measures of Vegetative Maturity in Red-osier Dogwood (Cornus stolonifera Michx.)1
Authors: Nissila P. C. , Fuchigami L. H.
Published: August 2022

Xylem water potential (XWP) and electrical impedance ratios were used to determine the time of vegetative maturity in red-osier dogwood (Cornus stolonifera Michx.) grown under 2 temperature and a short-day dormancy inducing regime in growth chambers and a lathhouse under natural conditions. The decline in XWP correlated with the development of vegetative maturity as measured by tip dieback after defoliation. Under growth chamber conditions, average XWP values reached a minimum at the time of vegetative maturity. In all cases, however, variability within samples was so large as to preclude the use of XWP as an accurate, reliable index of vegetative maturity. A change in electrical impedance ratios at and after vegetative maturity caused the impedance meter to go “off scale.” Compared with XWP values, changes in electrical impedance ratios were more consistent and show promise in predicting vegetative maturity.
Modification of Apple Quality by High Temperature1
Authors: Liu F. W.
Published: August 2022

High temperature (40°C) for 2 and 4 days lowered the acidity of 4 cultivars of apples (Malus domestica Borkh.). The preheated fruit was firmer than the control during 2 to 4 weeks of holding at 21°. The treatment also accelerated the loss of chlorophyll from the fruit skin. The soluble solid content of the fruit was not affected. Apples after the heat treatment had a normal respiratory climacteric and normal ethylene production rates. Some feasibility of applying high temperature to improve apple quality seems to exist.
Low Pressure and Refrigerated Storage of Rooted and Unrooted Ornamental Cuttings1
Authors: Eisenberg Barry A. , Staby George L. , Fretz Thomas A.
Published: August 2022

Rooted and unrooted cuttings of geranium (Pelargonium × hortorum, Bailey cv. Irene), poinsettia (Euphorbia pulcherrima, Wild cv. Annette Hegg Dark Red), tallhedge buckthorn (Rhamnus frangula L. cv. Columnaris), Regel's privet (Ligustrum obtusifolium Sieb. & Zuce. cv. Regelianum), and compact European cranberrybush viburnum (Viburnum opulus L. compactum), were stored up to 9 weeks using low pressure (LP) and refrigerated (RF) storage systems at 1.1 to 2.2°C with 95% relative humidity except for the poinsettia and geranium cuttings which were stored at 5±.5°C. Low pressure storage extended the storage life of rooted geranium and poinsettia cuttings 2 weeks beyond that achieved with RF storage. Unrooted geranium and poinsettia cuttings had 2 week and 4 day longer storage periods, with LP than RF storage, respectively. Unrooted compact European cranberry bush viburnum, Regel's privet, and tallhedge buckthorn cuttings stored 6 weeks using LP storage were superior to RF storage. Regardless of treatment, quality of all stored plant materials decreased with increased time in storage.
Compatability of Cabbage, Carrots, and Apples in Low Pressure Storage1
Authors: McKeown A. W. , Lougheed E. C. , Murr D. P.
Published: August 2022

Cabbage (Brassica oleracea var. capitata, cv. Quick Green Storage) and carrots (Daucus carota L., Nantes type) were stored successfully in low pressure storage (LPS) at 50-60 Torr and 1° and 5°C with ‘Delicious’ apple fruit (Malus domestica Borkh.). LPS conditions minimized the effect of the ethylene produced by the apples on leaf senescence and abscission of cabbage, and formation of a bitter flavor in carrots.
Deuterium-enriched Water Used to Show Absence of Water Movement in Thuja at Subfreezing Temperatures1
Authors: Pellett Harold M. , Carter John V. , Hummel Rita L. , Parsons Lawrence R.
Published: August 2022

Water uptake and movement in Thuja occidentalis pyramidalis Hort, during periods when soil was frozen were examined by use of deuterium as a tracer. Plants in containers were buried to the soil line and electric heating cables were placed below the pots. Deuterated water was added through access tubes when the soil was warmed above 0°C. The amount of deuterium tracer in the foliage was analysed with a gas chromatograph-mass spectrometer (GC-MS). Using this technique, it was found that no water moved from the roots to the foliage when the soil was frozen. When the soil temperature was raised above 0°C, tissue deuterium content increased 7 to 10 fold.
Chrysanthemum Growth at Cool Night Temperature1
Authors: Parups E. V.
Published: August 2022

Twenty-six cultivars of chrysanthemum (Chrusanthemum morifolium Ramat.) of the standard, pot-, or spray- type were grown in greenhouses at an 8 hour short-day and a night temperature of either 15.S°C, or a split temperature of 15.5° from 1600 until 2400 and 10° from 2400 until 0800, The day temperature was kept at 22° on sunny and 18° on cloudy days. Additional light (about 3000 lx) was provided for one half of the plants in each temperature treatment on cloudy days. Good chrysanthemums were produced under all conditions with all cultivars with but a minor delay (about 3 days) at the split high-low night temperatures. The plants were taller when grown at the split cool rather than the normal night temperature. The number and size of flowers were not affected significantly by the temperature treatments. Additional light increased stem length and increased the number of flowers of the spray-, and pot-type chrysanthemums. In the growth and production of greenhouse-grown chrysanthemums the split, cool temperature treatments provide energy savings without a noticeable change in growth and quality of plants.
Ethylene, Cellulase, 2,4-D, and Summer Fruit Drop of Navel Orange in Florida
Authors: Lima Jose Eduardo O. , Davies Frederick S.
Published: August 2022

Secondary-fruit yellowing (SFY) of navel orange [Citrus sinensis (L.) Osbeck], a major cause of summer fruit drop, was induced artificially by girdling the stem 5 to 10 cm from the fruit. Girdling from 26 to 28 May 1982 increased ethylene levels at the stylar end and induced SFY in 90% of treated fruit. Girdling at other times, or at 30 to 45 cm from the fruit, however, caused minor SFY, particularly if leaves were present between the fruit and girdled area, indicating some material is produced by the leaves that reduces the incidence of SFY. Increase of ethylene levels and cellulase activity in the abscission zone of the secondary fruit prior to increases in the abscission zone of the primary fruit indicate that secondary-fruit abscission leads to primary fruit abscission. Water stress or changes in nonstructural carbohydrate levels within the leaves induced by branch sawing did not cause SFY. Application of 2,4-dichlorophenoxyacetic acid (2,4-D) prior to or during induction lessened the severity of SFY and significantly decreased ethylene levels at the stylar end of the fruit.
Vesicular–Arbuscular Mycorrhizal Development and Growth Response of Rough Lemon in Soil and Soilless Media: Effect of Phosphorus Source
Authors: Graham J. H. , Timmer L. W.
Published: August 2022

Vesicular–arbuscular mycorrhizal (VAM) development of Glomus intraradices Schenck & Smith and growth response of container-grown rough lemon (Citrus jambhiri Lush.) were compared in a phosphorus-deficient (2 μg P/g) sand-soil and peat-perlite, soilless mix, both fertilized with 3 levels of superphosphate (SP) and rock phosphate (RP). Mycorrhizal development and growth response were affected primarily by initial P availability in the media. In both soil and peat-perlite, VAM formation was greatest at 8 μg available P/g medium and maximum growth responses occurred over a range of 4 to 8 μg P/g medium. Available P from SP greater than 20 μg P/g medium inhibited mycorrhizal colonization and eliminated growth response. Less VAM development in peat-based media compared to soil suggested an effect of organic matter. In peat-perlite, moderate levels of colonization and a growth response equal to that of nonmycorrhizal plants grown in soilless media with high levels of available P were attained if RP was used to provide a low but sustained level of available P. In soilless media, mycorrhizae prevented P-induced, copper-deficiency symptoms in rough lemon.
Imbibitional Chilling Injury during Chickpea Germination
Authors: Tony H. H. Chen , Yamamoto S. D. K. , Gusta L. V. , Slinkard A. E.
Published: August 2022

In the paper “Imbibitional Chilling Injury during Chickpea Germination” by Tony H.H. Chen, S.D.K. Yamamoto, L.V. Gusta, and A.E. Slinkard [J. Amer. Soc. Hort. Sci. 108(6):944–948, 1983], on page 946, Fig. 2 was omitted inadvertently during printing. The missing photograph and its caption appear below:
Rest Completion Prediction Model for ‘Starkrimson Delicious’ Apples
Authors: Shaltout Assem D. , Unrath C. R.
Published: August 2022

In the paper “Rest Completion Prediction Model for ‘Starkrimson Delicious’ Apples” by Assem D. Shaltout and C.R. Unrath [J. Amer. Soc. Hort. Sci. 108(6):959–961, 1983], there is an error on page 959 in footnote y for Table 6. The correct version of the footnote is as follows:

, where Tm = 4.4°C if temperature < 4.4°C; Tm = 25°C if the temperature is > 25°C.
The Influence of Summer Pruning and Cropping on Growth and Fruiting of Apple
Authors: Taylor B. H. , Ferree D. C.
Published: August 2022

Trees of apple [Malus domestica Borkh. cvs. Jonathan/Malling (M) 26] were summer-pruned each August from 1978-1980 by heading all shoots longer than 10 cm, and their response was compared to trees receiving only a light dormant-pruning by thinning-out cuts. Cropping treatments were a full crop or defruiting in June. Final length of shoot regrowth on summer-pruned trees was 82% and 76% less than terminal growth of control trees in 1979 and 1980, respectively, but terminal shoots produced the year following pruning were 55% and 62% longer on summer-pruned tress than on controls in 1979 and 1980, respectively. Summer-pruned trees with a full crop had 13% shorter terminal shoot length than defruited trees in 1979, but cropping had no effect in 1980. Trees with a full crop had a smaller annual increase in trunk cross-section than defruited trees, but were not affected by summer pruning. Summer pruning restricted tree canopy dimensions, resulting in 43% less canopy volume than control trees in 1979 and 1980, increased canopy openness to light penetration, and hastened flower opening. Pruning treatments did not affect fruit set. Fruit yield per tree was reduced by summer pruning, but yield per canopy volume was not affected. Fruit size was decreased by summer pruning in 1979 but was increased in 1980. Fruit soluble solids were reduced by summer pruning in 1979 and 1980, fruit color was increased in 1978 and 1980, but not in 1979. Flesh firmness was unaffected by summer pruning.
Reduction of Frost Injury to Almond by Control of Ice Nucleation Active Bacteria
Authors: Lindwo S. E. , Connell J. H.
Published: August 2022

Epiphytic populations of ice nucleation active (INA) strains of Pseudomonas syringae van Hall of up to 106cells/g fresh weight were found on healthy tissues of commercially managed almond [Prunus dulcis (Mill.) D.A. Webb] orchards in California. Leaf bacteria accounted for over 99% of the ice nuclei active at temperatures higher than − 5°C on almond. Large, seasonal variations in populations of INA bacteria and ice nuclei on almond were observed, with maximum populations found shortly after full bloom. These populations were reduced from 10- to 100-fold by 3 weekly applications of bactericides starting at budbreak, or a single application at 10% bloom of a nonice nucleation active antagonistic bacterium isolated from an almond leaf surface. Applications of cupric hydroxide to dormant tissues and/or to growing tissue after budbreak were most effective at reducing populations of INA bacteria and ice nuclei on almond. Application of bacterial ice nucleation inhibitors did not influence populations of INA bacteria on almond shoots shortly after application, but reduced the numbers of ice nuclei active at −5° or warmer. Frost injury to detached almond spurs cooled to −3° was reduced by all treatments that reduced the numbers of bacterial ice nuclei on almond tissue.
Effect of Calcium Infiltration on Ethylene Production, Respiration Rate, Soluble Polyuronide Content, and Quality of ‘Golden Delicious’ Apple Fruit
Authors: Sams Carl E. , Conway William S.
Published: August 2022

Fruit of ‘Golden Delicious’ apple (Malus domestica Borkh.) infiltrated after harvest with CaCl2 solutions of up to 12% (w/v) had lower ethylene production rates than untreated fruit during a 7-day period at 20°C immediately following treatment. However, after a 5-month storage period at 0° the effect of calcium on ethylene production diminished rapidly during a 7-day ripening period at 20°. Ethylene production for the 7-day period immediately following calcium treatment was correlated negatively to calcium concentration of the fruit. Calcium treatment had no significant effect on fruit respiration rate in this study. High calcium concentrations resulted in a decrease in the magnitude of ethylene production but had no effect on respiration. Titratable acidity and percentage of soluble solids were unaffected by calcium treatment even at high concentrations of CaCl2. Fruit firmness was correlated positively to calcium concentration of the fruit both before and after storage at 0°, and soluble polyuronide content of the fruit was correlated negatively to fruit calcium.
Rejuvenating Rabbiteye Blueberry ‘Tifblue’ and ‘Woodard’
Authors: Austin Max E. , Brightwell W. T.
Published: August 2022

Hedging reduced yield and increased fruit size of rabbiteye blueberry (Vaccinium ashei, Reade) for one or 2 years following hedging, but yields and fruit size were similar to unhedged plants after 4 years. The best hedging treatment time was February, with evaluation taking place over a 5-year period following hedging.
Postfertilization Hybrid Seed Failure in Lycopersicon esculentum X Lycopersicon peruvianum Ovules
Authors: Barbano P. P. , Topoleski L. D.
Published: August 2022

Lycopersicon esculentum Mill. X Lycopersicon esculentum (E X E) and interspecific Lycopersicon esculentum × Lycopersicon peruvianum (L.) Mill. (E × P) ovules were studied to determine the sequence of events leading to embryo and endosperm deterioration in E × P ovules. At 7 days, the single-celled zygote and multicellular endosperm stage, the E × P ovule showed no signs of abnormality. Endosperm deterioration was the first indication of anatomical abnormality. The endosperm had disintegrated totally by 10 days after pollination. The ExP embryo did not follow normal stages of embryo development but divided randomly, and at 17 days filled the embryo sac with an undifferentiated mass of cells. Deterioration of both the E x P embryo and the cells of the proliferated endothelium was complete by 24 days. The embryo sac cavity size of 14-day E × P ovules and the weight of 13-day ExP ovules also indicated that endosperm and embryo breakdown began in this interspecific cross earlier than the 30- to 40-day age reported by other researchers.
Pigment Content and Gas Exchange of Red Raspberry In Vitro and Ex Vitro
Authors: Donnelly D. J. , Vidaver W. E.
Published: August 2022

CO2 uptake and various leaf parameters were examined including photosynthetic pigment content (chlorophyll a, b, and total carotenoids), fresh/dry weight, percentage of water content, gram dry weight/area, and total plantlet leaf areas of an aseptically cultured clone of red raspberry (Rubus idaeus L.) incubated at 5 light intensities, from 2 to 6 klx. Cultured plantlets demonstrated relatively low levels of CO2 uptake, averaging 2.5 mg CO2 dm–2hr–1 and rarely exceeding 4 mg CO2 dm–2 hr–1 at saturating light intensities. Pigment content was higher in plantlets incubated at lower light intensities (2 to 4 klx). Cultures incubated at 3 klx were evaluated both at the time of transfer to soil and 1 month later. Plantlet leaves retained from culture could be distinguished from new leaves by tagging all plantlet leaves prior to soil transfer; both were assessed separately 1 month after transplantation. Leaves retained from culture, 30% of the total leaf area of transplants, contributed less than 10% of the CO2 uptake at 3 klx. These leaves accounted for 10% to 30% of the total leaf area at higher light intensities but were net respirers. There was an increase in dry matter accumulation at 6 and 9 klx in these tagged leaves, but not at 3 klx. Continued accumulation of dry matter by the tagged leaves can be only at the expense of photosynthetic activity of the newly formed leaves. New leaves of transplants had a greater dry matter accumulation at 9 klx and a pigment content greater than the tagged leaves. Their pigment content was similar to that of young, control plant leaves. Transplants were capable of uptake rates of 5–7 mg CO2 dm–2 hr–1 or 50% of field control rates. The photosynthetic contribution of the leaves from culture was small or negative. The first new leaves formed in soil were transitional with intermediate capability. Acclimatization to the soil environment was time dependent and required the production of new leaves initiated in the new environment.
Growth Response in Spinach to Sequential and Simultaneous Exposure to NO2 and SO2
Authors: Hogsett W. E. , Gumpertz M. L. , Holman S. R. , Tingey D. T.
Published: August 2022

Spinach (Spinacia oleracea L.) was exposed intermittently to NO2 and SO2 (2 hours/week; 0.8 or 1.5 ppm) in a simultaneous or sequential fashion over the 42-day growth period. Nighttime simultaneous exposure to NO2 and SO2 reduced growth and altered assimilate partitioning to the root. The relative growth rate of total plant and root was reduced significantly below controls early in the growth period. In contrast, neither daytime exposure to the pollutant mixture nor sequential exposure to the 2 pollutants affected growth.
Evaluation of Bloater Resistance in Pickling Cucumbers Using a Brine Carbonation Method
Authors: Wehner Todd C. , Fleming Henry P.
Published: August 2022

The feasibility of testing the resistance of pickling cucumber (Cucumis sativus L.) cultivars to bloater damage was determined using a procedure of artificial carbonation at several concentrations of dissolved CO2 during brine storage of unfermented cucumbers. The use of grade 3-size fruit carbonated to saturation with CO2 during brine storage in 18-liter (5-gal) plastic pails appeared to be a simple, rapid (6 days), inexpensive, and reproducible method to test for cultivar differences in susceptibility to bloater damage. The method involves the use of a prescribed brine composition and sequential introduction of N2 and CO2 into the brined cucumbers. Thirty-five cucumber lines and cultivars were statistically separable using the method. Based on the data collected, it is recommended that 6 replications of 15 grade 3 fruit per cultivar or line be used, although good data can be obtained with as few as 2 replications of 5 fruit.
In Vitro Development of Zygotic Embryos of Theobroma cacao
Authors: Kononowicz Andrzej K. , Janick Jules
Published: August 2022

Immature zygotic embryos of Theobroma cacao L. (cacao) were cultured for 46 days in a liquid medium based on Murashige and Skoog (MS) salts and standard vitamins. Embryos at about the 100-day-stage were stimulated to develop toward maturity, based on increased production of anthocyanins, alkaloids, and lipids, when sucrose levels in the medium were increased to 27% (10 days in 3%, 2 days each in 9%, 15%, and 21%, and 30 days in 27% sucrose). Lipid development of embryos in vitro corresponded to that of zygotic embryos in vivo and asexual embryos in vitro. Embryos at the 150-day-stage did not respond to the high sucrose protocol.
Influence of Storage Temperature and Ethylene on Firmness, Acids, and Sugars of Chilling-sensitive and Chilling-tolerant Tomato
Authors: Manzano-Mendez J. , Hicks J. R. , Masters J. F.
Published: August 2022

Two cultivars and 2 experimental chilling-tolerant lines of tomato (Lycopersicon esculentum Mill.) were harvested mature-green and stored for 15 days at 5°, 20°, and 35°C with or without the introduction of ethylene; portions of the high and low temperature samples were moved to 20° for an additional 10 days. Samples were analyzed for firmness, sugars, and acids. Fruit of the chilling-tolerant tomato lines were firmer than the commercial cultivars in all temperature treatments. Ethylene enhanced softening in the chilling-sensitive cultivars only at 20°, while the chilling-tolerant lines showed an effect only at 35°. The chilling-tolerant lines appeared to be more heat-tolerant than the sensitive cultivars. Sugar and organic acid analyses were not as clear-cut, often revealing a tendency for the cherrysized fruit to behave similarly to each other and different from the normal-sized fruit. The chilling-tolerant lines held at 5° or moved from 5° to 20° had lower monosaccharide levels than the corresponding sensitive cultivars. This also was true when fruit were moved from 35° to 20°. ‘New Yorker’ tomato had low levels of malate after exposure to 35°, which resulted in a high citrate/malate ratio not evident in the other 3 cultivars. Phosphoric acid levels were higher in the chilling-tolerant tomato fruit and increased with increasing storage temperature. Line 281 deviated from the other 3 cultivars in that, in general, acids increased and sugars decreased with increasing storage temperature.
Influence of N Source, N Rate, and K Rate on the Yield and Mineral Concentration of Sweet Potato
Authors: Hammett Larry K. , Miller Conrad H. , Swallow William H. , Harden Christel
Published: August 2022

‘Jewel’ sweet potatoes [Ipomoea batatas (L.) Lam.] were grown during 2 seasons to evaluate 3 N sources, 3 K rates, and 2 N rates on a sandy loam soil. Nitrogen source did not influence yield; however, NaNO3 significantly increased foliar and root Na concentrations over those obtained with NH4NO3 or Ca(NO3)2. Higher yields were obtained with 140 kg K/ha than with 70 or 280 kg K/ha and 101 kg N/ha than with 202 kg N/ha. No foliar or root mineral concentrations were deficient. Nitrogen, P, Ca, and Mg concentrations were lower in root than foliar tissues.
Dormant Pruning Influence on Auxin, Gibberellin, and Cytokinin Levels in Apple Trees
Authors: Grochowska M. J. , Karaszewska A. , Jankowska B. , Maksymiuk J. , Williams Max W.
Published: August 2022

The levels of auxin, gibberellin, and cytokinin were measured using bioassay methods in pruned and unpruned apple trees (Malus domestica Borkh. cv. McIntosh). Vigorous shoot growth following heavy dormant pruning was accompanied by an increase in cytokinin concentration in the tissues in the early spring. As cell division and cell expansion progressed, the levels of auxin and gibberellin increased. The gibberellin activity in samples from pruned trees was 3 times higher than in samples from unpruned trees. Pruning diminished the midsummer level of cytokinins in the annual shoots.
Genetic Potential to Improve Tomato Flavor in Commercial F1 Hybrids
Authors: Jones R. A. , Scott S. J.
Published: August 2022

F1 hybrids between high sugar and acid lines of tomato (Lycopersicon esculentum Mill.) were rated higher in sweetness, ‘tomato-like’, and overall flavor intensity than the high-acid parent common to the crosses. Titratable acidity and soluble solids content were responsible for most of the observed differences in sweetness. The results indicate that improved tomato flavor can be achieved by genetically enhancing sugar and acid content. Rapid gains in flavor quality might be achieved in horticulturally acceptable types through F1 hybrids.
The Effects of Ice Nucleation-active Bacteria on Temperatures of Ice Nucleation and Freeze Injury of Prunus Flower Buds at Various Stages of Development
Authors: Gross D. C. , Proebsting E. L. , Andrews P. K.
Published: August 2022

The effects of high (105 to 107 colony-forming units/g) and low populations of ice nucleation-active (INA) Pseudomonas syringae, strain B301D, on the ice nucleation temperatures and the amount of frost injury were determined for ‘Redhaven’ peach [Prunus persica (L.) Batsch.] and ‘Bing’ sweet cherry [Prunus avium (L.)] flower buds. The experiments were conducted from bud swell in early spring through the small, green fruit stages of development on INA bacteria-inoculated and -noninoculated flower buds that were either excised or attached to 10-cm segments of woody stem tissue. Shoots were immersed one minute in an INA bacterial suspension or sterile buffer 4 hours prior to freeze-testing. Excised-noninoculated buds supercooled to near −4°C before the first exotherm was determined, whereas inoculated buds attached to the stem supercooled only to −2.5°. Ice nucleation temperatures were about −3.0° for excised-inoculated and attached-noninoculated flower buds. The stem tissue contained a nonbacterial source of ice nucleation, active at temperatures similar to INA bacteria, that limited supercooling in the floral organs. While the ice-nucleation temperatures did not change with respect to bud development, the susceptibility of the floral organs to frost injury did change. Before the emergence of the petal tips through the calyx (frost-tolerant phase), the percentage of injury was reduced at higher ice nucleation temperatures, whether induced by stem tissue or inoculation with INA bacteria. Temperatures of −8 to −10° were required to give about 50% injury during this frost-tolerant phase compared with −3 to −4° in the later, frost-sensitive phase. Within a week of petal tip emergence from the calyx, the direct relationship between ice nucleation temperature and frost injury reversed, and the percentage of injury was inversely proportional to supercooling in flower buds. The flowers and fruit were injured by ice formation during the frost-sensitive phase regardless of whether ice was induced by INA bacteria or woody stem tissue.
Evaluation of Combining Ability, Heterosis, and Genetic Variance for Yield, Maturity, and Plant Characteristics in Bush Muskmelon
Authors: Kalb Thomas J. , Davis D. W.
Published: August 2022

Combining ability and heterosis for yield, maturity, and plant traits in bush muskmelon (Cucumis melo L.) were estimated through the use of a 6-parent diallel evaluated in 1981 at Excelsior, Minn. and at Santa Paula, Calif. The variance of GCA was greater than that of SCA for all traits. Minnesota 266 was the best general combiner for yield weight characteristics. Minnesota 101 was exceptional for GCA in those traits associated with earliness, and U.C. Perlita Bush and U.F. G508 combined well for main crop yield. Correlations between the performance of parental lines and the average of their hybrids were consistently positive and often significant. Favorable heterosis over the midparent was found for all traits but days to first fruit. Favorable heterosis over the superior parent was found for plant health and all yield traits except total number of fruit per plant. In a 3 × 10 design II at Excelsior, estimates of additive variance exceeded those of dominance variance in general, providing for moderately high heritability estimates (40–70%) for most traits.
Genetic and Nutritional Status in Bitter Pit- resistant and -susceptible Apple Seedlings
Authors: Korban Safi S. , Swiader John M.
Published: August 2022

Inheritance of the bitter pit disorder was determined in the field on fruiting seedlings resulting from crosses between the highly susceptible cultivar ‘Prima’, Coop 11 (a scab-resistant advanced selection), and 3 other scab-resistant selections. Segregation ratios indicated that 2 major genes controlled resistance. Both dominant genes, designated Bp-1 and Bp-2, were required to confer resistance. Analysis of leaf and peeled fruit tissues for Ca, Mg, K, and B indicated the presence of higher levels of Ca and B, and lower levels of Mg and K on a dry weight basis in resistant seedlings. A gradient was observed through the flesh on the fruit for all elements tested. Ca content was elevated at the base, but dropped rapidly towards the apex in susceptible fruits. Mg was reduced at the base and increased towards the apex in all fruits, but its level increased sharply in susceptible fruits.
Some Inorganic Element Changes in Trunk Phloem of Healthy and Blight-affected Citrus Trees
Authors: Williams G. L. , Albrigo L. G.
Published: August 2022

Levels of several inorganic elements were determined at one time in samples of trunk phloem from 3 adjacent pairs of healthy and blight-affected ‘Marsh Seedless’ grapefruit (2 groves) and ‘Pineapple’ orange (1 grove) trees on rough lemon rootstock. A smaller number of elements were determined seasonally over a 1½-year period in the trunk phloem from 3 similar pairs of healthy and declining trees per grove. Zn, Mn, and N levels in the trunk phloem of blighted trees were significantly higher than in healthy trees, and B levels were significantly lower in the one-time sample analysis for Zn, Mn, Cu, K, Na, Mo, B, Cl, and N. Zn and Mn levels were significantly increased in blighted trees for all samples during the seasonal analysis for Zn, Mn, Cu, K, and Na. Cu and K levels were significantly higher in blighted trees only on some sampling dates. Zn levels continued to increase with time in blighted trees. None of the other elements showed a consistent pattern of change with time. In a study of 5 elements in north- vs. south-side trunk phloem, only Zn in healthy trees was different consistently in each side of the tree.
Fourier Analysis of the Main Head Shape of Artichoke
Authors: De Pace Ciro , Delre Vitantonio , Scarascia-Mugnozza Giantommaso
Published: August 2022

A procedure for analyzing shape of the artichoke (Cynara scolymus L.) main head, independent of size, is presented. The method uses a Fourier harmonic model for fitting bud profile shape. Each of the parameters in the model describes a different 2-dimensional conformation of a main-head profile and jointly provides a close fit (r > 0.93) to observed profile coordinates. The parameters are amenable to statistical analysis and can be used in a quantitative study of shape when a continuous genetic distribution of shape profiles is observed.
Inter- and Intra-row Inter-genotypic Competition Influences Selection for Avoidance of White Mold Disease in Dry Edible Beans
Authors: Fuller Peter A. , Coyne Dermot P. , Steadman Janies R. , Mumm Robert F.
Published: August 2022

Two field experiments were conducted to explore possible causes of inefficient selection for architectural avoidance of white mold disease reported in dry beans (Phaseolus vulgaris L.). Near-isogenic breeding lines for maturity and plant growth habit were blended in 4 paired combinations (with 5 mixture levels/blend) to investigate their intrarow competitive influence on disease severity. Results from regressing the disease severity for each blend component on the mixture level showed the disease severity of an individual plant to be dependent upon its own maturity, as well as on the maturity of its neighbors. An increase in the proportion of late plants in the blend led to a significant and linear increase in their disease severity. A comparable decrease in disease severity was observed as the proportion of early plants in the blend was increased. Disease severity was not influenced by the proportion of indeterminate or determinate plants in the blend, regardless of maturity. The determinate growth habit, however, as well as early maturity, resulted in greater disease avoidance than the indeterminate growth habit or late maturity when grown in pure stands. In a 2nd experiment, 4 dry bean cultivars possessing different architectures were used to study the interrow influence of plant architecture on disease severity, incidence, and seed yield. Significant differences in disease severity and incidence observed between plots bordered by an upright genotype or a dense, prostrate genotype indicated that the level of disease in the test row was determined to a large extent by the architecture of adjacent rows. The failure to obtain an accurate assessment of a genotype's performance may account partially for the difficulty in selecting for architectural avoidance.
Sweet Corn Growth Responses and Leaf Concentrations as Affected by Lime Types and Fertilizer Treatments in a Five-year Study
Authors: Smith Cyril B.
Published: August 2022

A 5-year sweet corn nutrition experiment involving 4 lime treatments, 14 fertilizer treatments, and 2 hybrids was conducted on Hagerstown silt loam which had an initial pH of 5.2. Calcitic, calcitic with 3% Mg and dolomitic (12% Mg) limes applied during the 1st and 3rd years at 4.5 MT/ha increased vigor, yield, percentage of marketable ears, leaf N, leaf P and decreased leaf Mn and Zn. Calcitic lime increased leaf Ca and Mg by 21% and 31%, respectively. Dolomitic lime more than doubled leaf Mg but did not affect leaf Ca. Dolomitic lime increased leaf Mg by 55% 60 days after application. The best fertilizer responses were obtained with 56 kg/ha each of N and P banded for ‘Northern Belle’, with 112 kg/ha of N (75% broadcast, 25% banded), and 56 kg/ha P banded for ‘Deep Gold’. These treatments increased yields (by 36% and 60%, respectively, compared to the check), plant height, ear size and weight, and hastened maturity by 5 days. Additions of K or Mg did not improve the response. Height and yield were reduced and maturity was delayed when Ca (NO3)2 rather than NH4 NO3 was used as the N source. Leaf Ca, Mg, and Mn were lower with Ca (NO3)2 than with NH4 NO3 and urea sources, but leaf N, P, Mn, Cu and Zn increased with the urea source. Leaf Ca and Mg were enhanced by NH4 NO3, Ca (NO3)2, and urea, and depressed by KC1.
Phytotoxic Responses of Florida Grapefruit to Low-dose Irradiation
Authors: Hatton T. T. , Cubbedge R. H. , Risse L. A. , Hale P. W. , Spalding D. H. , von Windeguth D. , Chew V.
Published: August 2022

Seven irradiation tests (with exposures of 0, 7.5, 15, 30, 60 and 90 krad) were conducted on 26 lots of grapefruit throughout the 1981–82 and early 1982–83 citrus seasons. Fruit treated with 60 and 90 krad showed rind breakdown and scald after storage for 28 days at optimum temperatures. Scald was the dominant injury in early-season fruit in tests conducted during Oct. and Dec. 1981 and Sept, and Oct. 1982. Rind breakdown, especially pitting, was the dominant injury in all other tests with midseason and late-season fruit. At the 7.5-, and 15-, and 30-krad exposures, injury was minimal, and fruit exposed to these dosages were acceptable. Although some 60- and 90-krad exposures resulted in excessive injury, 2 tests at 60 and 90 krad were acceptable with early fruit. In some instances, injured areas developed decay after storage and marketing conditions at 21°C.
Stability Differences among Fresh Market Tomato Genotypes—1. Fruit Yields
Authors: Stoffella Peter J. , Bryan Herbert H. , Howe Teresa K. , Scott Jay W. , Locascio Salvadore J. , Olson Stephen M.
Published: August 2022

Ten fresh market tomato (Lycopersicon esculentum Mill.) genotypes were evaluated for yield stability in 7 environments within Florida. Genotype × environment interaction was significant for yield of marketable fruit. Linear relationships between mean yields of individual genotypes and environmental mean yields were evaluated to determine genotype stability. Mean square deviations from linear regression (s2d), regression coefficients (b1) and coefficient of linear determination (R2) were used to evaluate phenotypic stability. ‘Sunny’, Castlehy 1035’, ‘Burgis’, ‘FTE 12’, and ‘Duke’ were considered stable and high yielding. An advanced breeding line, 827015-IBK, was considered stable but low yielding. ‘Hayslip’, D76127, ‘Flora-Dade’, and ‘Walter PF’ were considered unstable. This study suggests that yield stability differences occur among fresh market tomato genotypes. Therefore, selection of tomato genotypes for improved adaptability should be considered in tomato breeding programs.