bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Thinning of Peach Fruits with CGA 15281 and CGA 178561
Authors: Byers R. E.
Published: August 2022

Beta-chloroethyl-methyl-bis-benzyloxy-silane (CGA 15281) was applied to 6 Eastern U.S. grown peach (Prunus persica (L.) Batsch) cultivars. Thinning response varied considerably with cultivar, timing, concentration and year. Unpredictable and commercially unacceptable leaf abscission occurred with most cultivars during the three-year period. Adequate thinning was achieved without excessive leaf abscission (10% or less) with only one treatment on 3 cultivars (‘Redhaven’, ‘Loring’, and ‘Sunhigh’) during the 3-year period. Reproducibility between years was not good. Unpruned trees or long 2-year-old limbs lost a greater portion of fruit at the base of shoots and on the interior of the trees than trees pruned to a uniform shoot length. The thinning response to CGA 17856 (an analogue of CGA 15281) was compared to the same rate of CGA 15281 on 5 cultivars. A tendency to greater leaf abscission was observed with CGA 17856.
Yield and Secondary Root Growth of Carrots as Influenced by Tillage System, Cultivation, and Irrigation1
Authors: Orzolek M. D. , Carroll R. B.
Published: August 2022

There were no significant yield differences among tillage systems of carrots (Daucus carota L. cv. Danvers 126) planted into a rye mulch, soybean stubble, and conventionally tilled plots. Secondary root growth of carrot was greater in soybean than either rye or conventionally-tilled carrot plots. Irrigation decreased secondary root growth in conventional tilled and rye mulch plots, but not in the soybean stubble.
Nitrate Reduction in Leaves of Grapevine and Other Fruit Trees1
Authors: Pérez J. R. , Kliewer W. M.
Published: August 2022

Optimum conditions for in vivo activity of nitrate reductase (NR) from grape leaves (Vitis vinifera L.) were pH 7.5, 100 mm NO3 substrate, and incubation at 40°C. Pretreatment with low concentrations of NO3 (0.05m) at room temperature did not increase activity substantially.

Induction of NR by NO3 substrate was investigated. Enzyme activity was maximum at the highest NO3 levels.

Intact-tissue assay detected NR in mature leaves of grapevines, walnut (Junglans regia L.), plum (Prunus domestica L.), pears (Pyrus communis L.), and sweet cherry (Prunus avium L.) grown under field conditions. In addition, a particulate NR was demonstrated in walnuts and grapevine leaves by in vitro assay.
Fruit Set of ‘Italian’ Prune Following Fall Foliar and Spring Boron Sprays1
Authors: Callan Nancy W. , Thompson Maxine M. , Chaplin M. H. , Stebbins R. L. , Westwood M. N.
Published: August 2022

A pre- or postharvest foliar B application was found to increase fruit set of ‘Italian’ prune (Prunus domestica L.). A prebloom B spray failed to increase set. Neither fall nor spring applications influenced the amount of fruit lost in the midsummer or “blue” drop. All trees involved in the experiment had adequate B by the standard index of tree nutrition, August mid-shoot leaf analysis. Incipient B deficiency did not appear to be involved.

Fall foliar B increased B levels in dormant bud and spur tissues and in flower buds and flowers. A prebloom B spray increased B levels of floral tissues to a lesser degree. The highest B concentration was found in the ovary. Boron concentration in flower buds in April following a fall B spray was as much as five times the amount found in mid-shoot leaves in August. August mid-shoot leaf analysis revealed higher levels in leaves from trees treated the previous fall in only one of the 2 years.

Several morphological and physiological effects of the fall B spray were observed. Among these were a slight delay in the time of bud break, a decrease in the size of flower buds and mature flowers accompanied by reduction of style and pedicel length, and a decrease in pollen germinability. B level of pistil and pollen had no effect on in vivo pollen tube growth rate.
Effect of Growth Regulators in Branching, Flowering, and Fruit Development of Ornamental Pepper (Capsicum annum L.)
Authors: Khademi M. , Khosh-Khui M.
Published: August 2022

In the paper entitled “Effect of Growth Regulators in Branching, Flowering, and Fruit Development of Ornamental Pepper (Capsicum annum L.)” by M. Khademi and M. Khosh-Khui (J. Amer. Soc. Hort. Sci. 102(6).796-798. 1977) the description for Figure 1 should read “C1 is control and C2 to C4 represent 300,600, 900 ppm ethephon, 400, 800, 1200 BA, and 50,100, 150 ppm IAA, respectively.”
Time-dependent Coagulation of Young Shoot Homogenates of Citrus1
Authors: Esen Asim , Soost R. K.
Published: August 2022

Young shoot homogenates from some noncoagulating taxa coagulated either within 5 or 30 minutes depending on the taxon; others did not coagulate even after 30 minutes. Such time-dependent coagulation behavior or its absence is taxon-specific and appears to have uses as an additional marker in taxonomic and genetic studies in Citrus and to identify zygotic and maternal seedlings from crosses of 2 polyembryonic cultivars if the parents have the contrasting traits. Genetic data obtained from two F1 populations, an F2 population, and a presumed back-cross indicate that the character may be controlled either by 1 or 2 gene pairs.
Evaluation of Different Methods to Assess Cold Hardiness of Peach Trees1
Authors: Yadava U. L. , Doud S. L. , Weaver D. J.
Published: August 2022

The reliability, capability to predict survival, and convenience of 5 cold hardiness tests — triphenyl tetrazolium chloride reduction (TTC), electrolytic conductance (EC), ninhydrin-reactive compounds (NRC), trunk cambial browning (TCB), and bacterial canker development (BCD) — were evaluated using previous season's twigs of ‘Redhaven’ peach (Prunus persica (L.) Batsch) during the 1976-77 dormancy season. TTC, NRC, and EC were all significantly correlated with TCB as well as percent tree survival (PTS) in the field, and thus proved to be quantitative, reliable and capable of predicting survival at a later date. No statistical correlation was found between BCD and other hardiness tests.
The Potential Use of Antitranspirants in the Greenhouse Production of Chrysanthemum1
Authors: Martin John D. , Link Conrad B.
Published: August 2022

Three film-forming antitranspirants were applied to potted chrysanthemums (Chrysanthemum morifolium Ramat.) under greenhouse conditions from the time of potting rooted cuttings to saleable size. Folicote (a hydrocarbon wax emulsion of essentially fully refined paraffin) reduced water loss by an average of 39% and by as much as 65%, but generally detracted from plant appearance, delayed flowering, depressed fresh and dry weight, decreased flower size, increased height and reduced leaf area. While Clear Spray (a lateral based emulsion of undefined composition) and Wilt Pruf NCF (whose active ingredient is a polyterpene compound, Pinolene) reduced water loss 8 and 11% respectively, their side effects were less deleterious and, in a few cases, beneficial. Effects of antitranspirants under summer greenhouse conditions appeared to be of a greater magnitude than during a cooler season of the year.
Hybridization Among Diploid and Tetraploid Forms of New Guinea, Java, and Celebes Impatiens spp.1
Authors: Arisumi Toru
Published: August 2022

Interspecific hybrids were synthesized by intercrossing diploid and tetraploid of Impatiens spp. from New Guinea (2x=32), Java (2x=16), and Celebes (2x=8). Breeding analysis of the intra- and interploidy crosses showed that the species functioned as diploids in relation to each other. Diploid by tetraploid crosses produced little or no seed, and with few exceptions the triploid seedlings were sterile. All but 2 out of 43 seifs and reciprocal crosses among tetraploids produced viable seed. Amphidiploid and autotetraploid seedlings were pollen and seed fertile. Allotetraploids composed of 2 or 3 genomes in various unequal combinations and those with 4 genomes were pollen and seed sterile or nearly so. Most of the 3 and 4 allopolyploids were ornamentally inferior to the diploid and amphidiploid hybrids. New Guinea flower colors were recessive to those of Java and Celebes. The hybrid phenotypes were midparental for most traits and in some cases exhibited dosage effects. Some hybrids were superior to both parents in certain ornamentally important attributes.
Growth and Yield of Crops Treated with Triacontanol1
Authors: Ries Stanley K. , Richman Terry L. , Wert Violet F.
Published: August 2022

The growth of several vegetable and field crops in the greenhouse was increased by applications of 1-triacontanol to the foliage, soil, or seed. Neither the seed nor soil treatments increased the yield of crops in the field. However, foliar sprays ranging from 5 to 500 mg/ha significantly increased the marketable yield of 7 of 10 crops tested. The average yield increase was based on comparisons of all the different rates and time of 1-triacontanol applications with untreated controls. The response of tomato, carrot and wheat seed treatments with 1-triacontanol was shown to be positively correlated with temperature at time of germination and early growth.
Apple Fruit β-galactosidase and Softening in Storage1
Authors: Wallner Stephen J.
Published: August 2022

Fruit softening of apple (Malus domestica Borkh.) and the activity of β-galactosidase in 0.5 m citrate extracts of fruit cortex were compared for ‘Lodi’, ‘McIntosh’, ‘Golden Delicious’, and ‘York Imperial’ during storage at 0° or 3.3°, 10.0°, and 18.3°C. Enzyme activity per g fresh weight increased as fruits softened, but specific activity did not change. Cell wall galactose content also decreased during softening. The decrease in wall galactose was least in ‘Lodi’ which contained the lowest β-galactosidase activity. ‘York Imperial’ which softened most slowly showed the highest β-galactosidase activity at harvest and throughout storage. Concentrated enzyme preparations did not release measurable amounts of reducing sugar, uronic acid, or neutral hexose from isolated cell walls.
Effects of Harvest Date and Ethylene Concentration in Controlled Atmosphere Storage on the Quality of ‘McIntosh’ Apples1
Authors: Liu F. W.
Published: August 2022

‘McIntosh’ apples (Malus domestica Borkh.) were harvested on 3 different dates and stored in controlled atmosphere (CA) storage with less than 1, 10 or 500 ppm ethylene. After 5 and 8 months of storage the fruits which had been harvested 5 to 6 days before the onset of the climacteric were less ripe and had less breakdown than fruits harvested after the onset of the climacteric. The fruits harvested at the preclimacteric stage had either comparable or slightly better eating quality but less red color than fruits harvested later. High levels of ethylene had slight but statistically significant negative effects on firmness and acidity of early harvested fruits judged by sensory evaluation after 5-month storage plus 7-day holding and by objective evaluation after 8-month storage plus 1- or 7-day holding at 21°C. An attempt was made to find a method to estimate the physiological age of preclimacteric apples. The minimum treatment time required for 10 ppm ethylene to trigger the onset of the climacteric at 21°C is judged to be promising.
Residues of Acephate and Methamidophos in Greenhouse Tomatoes1
Authors: Leidy R. B. , Sheets T. J. , Sorensen K. A.
Published: August 2022

Acephate was applied to greenhouse tomatoes (Lycopersicon esculentum Mill.) as single and multiple applications, and residues on the fruits were determined several times after treatment. Immediately after application, residues of acephate averaged 0.46, 0.83, and 1.81 ppm for plots receiving 0.56, 1.12, and 2.24 kg/930 liter solutions, respectively. By day 7 residues of acephate, averaged over all rates, were 5.4% of day 0 values. Residues of methamidophos, a metabolite of acephate, were detected in all samples except those for day 0, but differences between rates and days after application were not significant. A statistical comparison of residue data showed that total residues (acephate plus methamidophos) were significantly greater after spraying once a week for 4 weeks than after a single application.
Inhibition of Ripening Processes in Pears by Inhibitors of Cyanide-resistant Respiration and by Silver1
Authors: Janes Harry W. , Frenkel Chaim
Published: August 2022

Various concentrations of salicylhydroxamic acid and alpha, alpha-dipyridyl (reported inhibitors of cyanide-insensitive respiration) applied to fruit of ‘Bose’ pear (Pyrus communis L.) reduced fruit softening. The application of silver ions, reported to inhibit ethylene action, delayed ripening.
Response of Cole Crops to Combinations of Herbicides and Insecticides 1
Authors: Freeman Jack A. , Finlayson D. G.
Published: August 2022

Over a 6-year period (1969-1974) the efficacy of 3 insecticides and 24 herbicides and their interactions in combination were investigated when applied to field-seeded broccoli (Brassica oleracea L. Italica group), cabbage (Capitata group) and cauliflower (Botrytis group). Of these, broccoli was the most susceptible to injury. Of 212 herbicide-insecticide combinations, 26 caused phytotoxic symptoms in broccoli, 20 in cabbage and 8 in cauliflower. The insecticides, thionazin, fensulfothion and carbofuran, were each involved in 1 or more phytotoxic combinations in each of the 3 crops. Ten herbicides were involved in phytotoxic reactions: alachlor, aziprotryn, benefin, CDEC, chlorpropham, cycloate, prometryne, propachlor, prynachlor and PP493. Root maggot damage was reduced markedly by the insecticides. Carbofuran allowed less damage than either fensulfothion or thionazin. None of the herbicides showed any insecticidal properties, and some decreased the effectiveness of the insecticides.
Variability in Noninfectious Bud-failure of ‘Nonpareil’ Almond. II. Propagation Source1
Authors: Kester Dale E. , Asay R. N.
Published: August 2022

Different propagation sources within ‘Nonpareil’ almond (Prunus amygdalus Batsch) showed wide differences in susceptibility to noninfectious bud-failure (BF). Seven years observations in a high temperature test location showed a range in BF-susceptibility from 0 to 100% depending on the source tree used for budwood. Selection of individual symptomless source trees resulted in separate clones that produced either no BF or high uniform percentages of BF-trees. Such single tree selection is a basis for selecting BF-resistance within cultivars. The nursery sources studied showed percentages from 0 to 62% suggesting that mixtures of normal and BF susceptible plants existed within the propagation sources. Propagation material randomly sampled from 10-year-old symptomless orchard trees from a hot summer location produced significantly higher percentages of BF trees in 6 years (2.3%) than propagation material from a cooler location (1.2%).
Ethylene in fruits of blackberry and rabbiteye blueberry
Authors: Lipe John A.
Published: August 2022

In the paper, Ethylene in fruits of blackberry and rabbiteye blueberry by John A. Lipe (J. Amer. Soc. Hort. Sci. 103(1):76-77, 1978), the ethylene concentration in the text expressed as mg/liter should be μl/liter or ppm.
Modification of Cucumber Response to Seed Grading and Nitrogen Source by Soil Compaction1
Authors: Smittle D. A. , Williamson R. E.
Published: August 2022

Removal of 20% of the seed of a commercial ‘Poinsett’ seed lot in a vertical air column increased the mean thickness and weight of the remaining seed. Fruit yield was increased by use of thicker, heavier seed when yield potential was not limited by high soil strengths. Seed grading effect on cucumber yield was less when either soil compaction or climactic conditions reduced yield potential. A combination of both yield limiting factors eliminated seed grading effect. Yield response to source of nitrogen was different when cucumbers were grown on compacted and noncompacted seedbeds. An interaction of seed grade, nitrogen source and seedbed compaction on marketable fruit yield was found.
Responses of Scab-resistant Derivatives of Malus Species to Infection with Common Viruses1
Authors: Cummins J. N. , Lamb R. C. , Welsh M. F. , Gilmer R. M.
Published: August 2022

Of 31 preliminary selections from the Geneva scab-resistance apple breeding program inoculated with apple chlorotic leaf spot virus (CLSV), 18 clones exhibited sensitivity during the first 2 growing seasons. Six advanced selections, all derivatives of the virus-sensitive Malus floribunda 821, were inoculated with CLSV or with a combination of other graft-transmissible agents that occur commonly as latent infections in apple. None of the 6 exhibited visible symptoms associated with virus content during 3 growing seasons; growth of 1 selection was slightly depressed. In a 3rd test, 1 of 7 advanced selections derived from M. floribunda exhibited depressed growth in an orchard trial on virus-infected Mailing (M) 9 rootstocks, compared to growth on virus-free M 9.
Insect Resistance as an Adjunct or Alternative to Insecticides for Control of Sweet Potato Soil Insects1
Authors: Cuthbert F. P. , Jones Alfred
Published: August 2022

Insect resistance in sweet potatoes (Ipomoea batatas (L.) Lam.) was more effective than fonofos, O-ethyl-S-phenylethylphosphonodithioate, in reducing insect injury to the roots. The most recent resistant line tested did not sustain economic injury from relatively high insect infestations even without the protection of an insecticide. Fonofos at 2.24 and 4.48 kg/ha did not prevent economic injury to the susceptible ‘Goldrush’.
Silver Ion Inhibits Ethylene Synthesis and Action in Ripening Fruits1
Authors: Saltveit Mikal E. , Bradford Kent J. , Dilley David R.
Published: August 2022

Ag(I), applied in aqueous solution as AgNO3, inhibited ethylene synthesis and ripening of mature green banana fruit slices and pericarp discs of mature green tomato fruit. It also inhibited ethylene production by cortical tissue from post-climacteric apples. Concentrations of Ag(I) which reduced ethylene synthesis had an inconsistent effect on CO2 production: no effect on banana slices (1.0 mm Ag+), stimulation in apple tissue (0.1 mm Ag+), and inhibition in tomato tissue (0.3 mm Ag+). This was accompanied by a slight amount of tissue necrosis at these concentrations. Of the 7 metallic salts tested, only Ag(I) inhibited ripening and ethylene synthesis at observed non-phytotoxic levels. Inhibition of ripening and ethylene synthesis by Ag(I) was evident in tissue treated with sufficient exogenous ethylene to elicit both responses in control tissue. The inability of applied ethylene to overcome the inhibitory effect of Ag(I) suggests that the silver ion may interfere with the primary action of ethylene in the tissue.
Shoot Apex Development and Rooting of Pinus strobus L. by Dwarf Shoots1
Authors: Cohen Michael A.
Published: August 2022

Foliar applications of benzyladenine (BA) increased bud development of dwarf shoots of Pinus strobus L. When compared to dikegulac-sodium (Atrinal), pyranybenzyladenine (PBA), gibberellic acid (GA3), or pinching. Differences in rate of application of BA were not significant. Vegetative propagation of dwarf shoots varied between individual clones and between years.
Seasonal Variation in Nitrate Uptake Efficiency and Distribution of Absorbed Nitrogen in Non-bearing Prune Trees1
Authors: Weinbaum S. A. , Merwin M. L. , Muraoka T. T.
Published: August 2022

Non-bearing prune (Prunus domestica L. cv. Agen) trees were fertilized with 15N-KNO3 for 10 days during 9 phenological periods. Nitrate uptake efficienty (NUE) and the distribution of absorbed 15N in the trees were determined for each of these application periods. Nitrate uptake was dependent on presence of leaves, and NUE was low from the period of natural leaf fall until shoot growth had commenced the following spring. NUE increased dramatically during the rapid phase of shoot elongation, and remained high until leaf fall. Nitrogen absorbed from fertilizer was rapidly mobilized by swelling buds and rapidly elongating shoots. The spring flush of vegetative growth utilized both the currently available fertilizer (15N) nitrogen and tree nitrogen reserves. Rapid shoot elongation was primarily dependent, however, on the redistribution of storage N.
Stunting of Citrus Seedlings in Fumigated Soils in Texas and its Correction by Phosphorus Fertilization and Inoculation with Mycorrhizal Fungi1
Authors: Timmer L. W. , Leyden R. F.
Published: August 2022

Stunting of sour orange seedlings was observed in seedbeds which had been fumigated chemically, heat-treated, or planted in soil-less media. Mycorrhizae were consistently absent from stunted seedlings and present in vigorous seedlings in seedbeds and nurseries and also present in orchards. Inoculation with Glomus fasciculatus (Thaxter) Gerd. & Trappe increased seedling height more than 300% and increased foliar phosphorus concentrations in greenhouse experiments on sour orange seedlings grown in sand culture with complete nutrient solution. Preplant application of P at 200 mg/liter did not increase growth or foliar P concentrations under the same conditions. Inoculation of seedlings receiving 0 to 800 mg P/liter with G. fasciculatus increased growth where 0 or 100 mg P/liter was added, but not where higher rates of P were used. Application of high rates of P induced copper deficiency symptoms, which were more severe on non-mycorrhizal than on mycorrhizal plants.
Determination of Irrigation and Fertilizer Practices for Jade Plant [Crassula argentea (L.) Thunb.]
Authors: Spooner J. , Daley L. , Ware G. , Vines M.
Published: August 2022

In the Table of Contents of the May issue of the Journal the name of L. Daley was misspelled in the listing of the article, Determination of Irrigation and Fertilizer Practices for Jade Plant [Crassula argentea (L.) Thunb.]by J. Spooner, L. Daley, G. Ware, and M. Vines [J. Amer. Soc. Hort. Sci. 103(3):306-308; 1978] due to a printer's error. The name is correctly spelled in the byline of the article itself.
Uptake of 14C-Release in ‘Valencia’ Oranges as Affected by Location on the Fruit, Temperature, Humidity, Treatment Duration and Fruit Position on the Tree1
Authors: Kossuth S. V.
Published: August 2022

Uptake of 14C-Release (3-methyl-4-nitro-5-chloro-1H-pyrazole) by oranges was determined 5, 8, 12 and 24 hours after treatment in 16 different controlled environmental conditions designed to test the effect of temperature and humidity. Significant interactions precluded ascribing variations in uptake to a single factor, but there was a definite trend of increased uptake with increasingly warmer temperatures and to a lesser extent increased uptake with increasing humidity. There was significantly more uptake occurring at the equator than at the stylar and stem ends of individual oranges. There was not a marked difference in uptake by fruit from the top of the canopy to the bottom.
Gums and Mucilages in Hulls of Almonds1
Authors: Ryugo K. , Labavitch John
Published: August 2022

Large clonal variations and seasonal fluctuations were observed in gum and mucilage content of hulls from 17 cultivars of almonds, (Prunus amygdalus Batsch.). Analysis of ethanol insoluble substances revealed that their content of neutral sugar and uronic acid residues were nearly the same. Additional analyses indicated a variety of polysaccharide types in the gum samples.
The Effect of Pre-storage Heating on Ripening and Senescence of Apples during Cold Storage1
Authors: Porritt S. W. , Lidster P. D.
Published: August 2022

Exposing ‘Spartan’ or ‘Golden Delicious’ apples (Malus domestica Borkh.) to 38°C for 4 to 6 days immediately after harvest suppressed softening during subsequent storage at −1°C 90 to 94% relative humidity. The rate of acid loss during the period of heating was rapid, but returned to normal during cold storage. Breakdown, core browning, and decay of ‘Spartan’ apple were almost eliminated by the heat treatment. There were no physiological disorders in the ‘Golden Delicious’.
Genetics of Flowering in Dry Beans (Phaseolus vulgaris L.)1
Authors: Coyne Dermot P.
Published: August 2022

In growth chambers at 26°±2°C (day) and 21°±2° (night), a 15 hour photoperiod delayed flowering on ‘Great Northern (GN) Nebraska #1 sel. 27’ by 47 days and in Plant Introduction (PI) 207262 by 48 days over a 10 hour photoperiod. The cultivars ‘GN 1140’ and ‘GN Nebraska #1’ and a near-isogenic determinate ‘GN Nebraska #1’ flowered at the same time under both photoperiods. Both near-isogenic lines, determinate and the early flowering ‘GN Nebraska #1 sel. 27’ flowered earlier than ‘GN Nebraska #1 sel. 27’ in all field experiments. The near-isogenic determinate ‘GN Nebraska #1’ flowered earlier than the ‘GN Nebraska #1 cultivar in 2 out of 3 field experiments. The delay in flowering of ‘GN Nebraska #1 sel. 27’ was much greater at higher night temperatures at Lincoln than under lower temperatures at Scottsbluff when the photoperiod was the same. Delayed flowering of PI 207262 under long photoperiod was controlled by a single recessive gene.
Iron Chlorosis and Mineral Content of ‘Fay Alberta’, ‘Shippers Late Red’ and ‘Redhaven’ Peach Trees as Affected by Iron Chelates1
Authors: Rogers Ewell
Published: August 2022

Sodium ferric ethylene di (o-hydroxyphenylacetate) (FeEDDHA) increased Fe and reduced Mn concentration in leaves of ‘Fay Elberta’, ‘Shippers Late Red’ and ‘Redhaven'peach trees (Prunus persica (L.) Batsch) and reduced Fe chlorosis and depressed the leaf Mn:Fe ratio. FeEDDHA increased Fe and reduced leaf Mn more than did equivalent amounts of sodium ferric ethylene bis (α-amino-2-hydroxy-5-methylphenylacetate) (NaFe) and hydrogen ferric ethylene bis (α-amino-2-hydroxy-5-methylphenylacetate) (HFe). FeEDDHA at 14 g of Fe per tree increased size and yield of ‘Redhaven'peaches. NaFe increased Fe and reduced Mn of the leaves and decreased Fe chlorosis of ‘Fay Elberta’ and ‘Shippers Late Red’ trees. HFe increased Fe and reduced Mn of the leaves and decreased Fe chlorosis of ‘Redhaven’ and ‘Fay Elberta’ trees. The treatments had no discernible effects on Zn concentration of the leaves or on shoot growth.
Response of Apple Buds Cultured in Vitro to Abscisic Add
Authors: Singha Suman , Powell Loyd E.
Published: August 2022

Abscisic acid (ABA) inhibited bud break and shoot elongation in seedling stem explants of apple (Malus domestica Borkh cv. Northern Spy) cultured in vitro. Inhibition was complete in culture medium containing 100 μM ABA. Transfer of buds from ABA-containing medium to basal medium resulted in increases in both bud break and shoot elongation. ABA levels in such buds declined rapidly following transfer, and growth began when ABA concentration in the buds dropped below a threshold value.
Light-sorting Muscadine Grapes (Vitis rotundifolia Michx.) for Ripeness1
Authors: Ballinger W. E. , McClure W. F. , Nesbitt W. B. , Maness E. P.
Published: August 2022

Spectral curves of fresh berries of both bronze and black muscadine grapes representing a wide range of ripenesses were obtained with a multipurpose spectrophotometer at the Pioneering Instrumentation Laboratory of the U.S. Department of Agriculture at Beltsville, Md. Using these curves, wavelength-pairs of 546-610 nm for bronze and 740-800 nm for black grapes were selected. A Berrymatic (high-speed fibre-optic sorter) developed for sorting blueberries was fitted with pairs of narrow band interference filters of the above wavelengths. Several tests over a 2-year period indicated that both black and bronze grapes can be light-sorted according to ripeness, as confirmed by destructive analyses of pH, soluble solids and acids in the fruits. Berry size and orientations of the berry on the light-sorter with respect to the light path influenced readings.
Calcium and Magnesium Levels in the Annual Rings of ‘McIntosh’ Apple Wood1
Authors: Blanpied G. D. , Oberly G. H.
Published: August 2022

Analyses were made of Ca and Mg in a consecution of annual rings of 3 mature ‘McIntosh’ apple (Malus domestica Borkh.) orchard blocks in New York (acid rain region) and also 3 mature ‘McIntosh’ blocks in British Columbia (arid-irrigated region) in an attempt to assess the long range effects of acid rain on Ca levels in apple trees. Differences in patterns of Ca and Mg deposition in the wood did not appear to be caused by acid rain.
Boron Uptake by ‘Bartlett’ Pear Trees as Influenced by Soil Retention and Leaching1
Authors: Whiting D. E. , Crandall P. C. , Woodbridge C. G.
Published: August 2022

Boron was applied to the surface of 3 southern Washington soils at rates of 0, 3.4, 6.7, and 13.4 kg/ha. Levels of hot-water-extractable B were measured annually to a depth of 90 cm for 3-5 years following application. Soils ranged from medium to high in B retention capacity. Once the B retention capacity of the soils was satisfied, additional B leached readily through the profile. The same amounts of B were applied to the same soil types in 3 commercial pear orchards to determine the effects on plant uptake. Blossom, leaf, and fruit levels of ‘Bartlett’ pear (Pyrus communis L.) were little affected by the applications, even though the extractable soil B levels were high. This failure to obtain uptake may be explained by dry soil conditions and reduced root activity resulting from low rainfall and low soil temperatures.
Spring Bud Development of Malus and Prunus Species in Relation to Soil Temperature1
Authors: Hammond Max W. , Seeley Schuyler D.
Published: August 2022

Soil temperatures around roots of apple (Malus domestica Borkh.), peach (Prunus persica (L.) Batsch), and cherry (Prunus avium L.), were modified during anthesis. Cool (1.5 – 9°C) and cold (1 – 4.5°) soil temperatures in the field were achieved with white plastic covers over insulation over snow, and with coolant coils in the soil covered with insulation and clear plastic. Warm (5 – 19°) and hot (18 – 26°) soil temperatures were achieved with clear and black plastic covers over bare soil and with buried heat tapes under insulation and clear plastic. Potted peach seedlings were subjected to freezing (−3°) and warm (18°) soil temperatures in a growth chamber. No advance or delay of anthesis resulted from any of the treatments except delay in frozen soil.
Effect of Shade Applied at Consecutive Periods on Sweet Corn Development1
Authors: Andrew R. H. , Bums M. C.
Published: August 2022

Artificial shade was applied at 7 successive 5-day periods in the field and greenhouse to 3 adapted inbreds of sweet corn (Zea mays L.). In the field, shade periods associated with high rainfall and temperature and low natural sunlight tended to limit development most; periods associated with high natural sunlight had least effect. Shade effects were more marked when applied to less vigorously growing plants. Shade suppressed dry weight and leaf area most for the early, small inbred. The late inbred was most stable. Shade suppressed ear length most for the inbred with an inherent tendency toward tip blanking. Dry weight and leaf area were significantly correlated in the field. All characters were positively and usually significantly correlated in the greenhouse.
Long-term Effects of Different Irrigation Regimes on Grapefruit Tree Development and Yield1
Authors: Levy Y. , Bielorai H. , Shalhevet J.
Published: August 2022

Grapefruit (Citrus paradisi Macf.) trees were irrigated for 14 years at interval of 18 to 40 days. Water stress due to irrigation at long intervals reduced vegetative development and yield. Cumulative water consumption, yields and canopy volume were closely correlated.
Germination Promotor and Inhibitor in Leachates from Tomato Seeds1
Authors: Abdul-Baki Aref A. , Stoner Allan
Published: August 2022

The leachate from seed of tomato (Lycopersicon esculentum Mill., PI 341984), an accession whose seeds germinate well at low temperatures, promoted the germination of seeds of the same and other tomato cultivars. The leachate from ‘Red Rock’ seed, a cultivar whose seeds germinate poorly at low temperatures, inhibited the germination of seeds of the same and other tomato cultivars. The promotive and inhibitory effects of these leachates on seed germination is apparently highly specific and restricted to tomato seeds. The activity was highest in fresh seeds and the responses were best exhibited at low germination temperatures.
The Effects of Ethyl Hydrogen 1-Propylphosphonate on Xylem Development and Differentiation in American Elm1
Authors: Dickinson P. R.
Published: August 2022

Foliar applications of ethyl hydrogen 1-propylphosphonate (EHPP) to 2- to 3-year old American elm (Ulmus americana L.) resulted in anatomical changes in xylem development which may be related to reduced susceptibility to the Dutch elm disease (DED) pathogen [Ceratocystis ulmi (Buis.) C. Moreau]. Xylem of treated elms had a reduced number of large diameter conducting elements; however, the number of contiguous conducting xylem elements per group of tracheary elements was increased. The treated plants had a unusually high concentration of stored cellular products, primarily starch grains, in parenchyma cells. Bands of concentric rings of parenchyma cells with dense contents were observed. Treatment induced an increased number of wood rays and inhibited elongation of pitted vessel members. The elimination of the wide conducting xylem elements caused by EHPP and the consequent effect it could have on the passive flow of fungal elements in the sapstream, may potentially be a deterrent to mobilization of the DED pathogen.
Effects of pH Level and Nitrogen Source on Elemental Leaf Content of ‘Tifblue’ Rabbiteye Blueberry1
Authors: Spiers J. M.
Published: August 2022

Leaf contents of N, P, Ca, Mg, Mn, and Fe were highest in plants fertilized with (NH4)2SO4 in a sand culture study conducted with 2-year-old ‘Tifblue’ rabbiteye blueberry (Vaccinium ashei Reade) plants. Nitrogen sources caused no differences in leaf uptake of Al, Zn, B, Cu, and K. Amounts of applied S and Na and leaf content of these elements were positively correlated. Leaf mineral content was not influenced by pH levels from 3.5 to 7.5. Shoot length and number of flower buds were not affected by pH, but both were highest for plants fertilized with (NH4)2SO4.
The Relationship between Vegetative Maturity and the First Stage of Cold Acclimation1
Authors: Nissila P. C. , Fuchigami L. H.
Published: August 2022

Red-osier dogwood (Cornus stolonifera Michx.) plants were grown outdoors in a lathhouse to study the relationship between vegetative maturity and the first stage of cold acclimation. Both microscopic observations and electrical impedance ratios used to measure damage of frozen stem sections verified the close association of the onset of the first stage of cold acclimation and vegetative maturity. The relationship of these processes to dormancy development is discussed.
Effect of Nitrogen Applications on Bloom Delay and Levels of Abscisic Acid, Carbohydrates, and Nitrogen in Peach Buds1
Authors: Reeder B. D. , Bowen H. H.
Published: August 2022

Soil applications of nitrogen in February and August delayed bloom of trees of ‘Redglobe’ peach (Prunus persica (L.) Batsch) the following spring. Applications of 67 to 134 kg N/ha delayed bloom progressively from 12 to 72 hours when compared to trees receiving no N. Buds from trees that received high levels of N contained higher levels of abscisic acid (ABA) and N and lower levels of carbohydrates (CHO) than did those from trees receiving no soil-applied N. ABA levels decreased sharply and CHO levels increased in buds from all treatments upon completion of the chilling requirement (850 hours). Delays in bloom of more than 24 hours prevented significant spring freeze damage in 1975.
Total and Reduced Ascorbic Acid Levels in Rin and Normal Tomatoes.1
Authors: Gonzalez Alfredo R. , Brecht P. E.
Published: August 2022

Changes in reduced ascorbic acid in normal tomato fruits (Lycopersicon esculentum Mill.) during holding at 20°C seem to be related to ripening. No change in reduced ascorbic acid levels from mature green to yellow rin fruits was observed when detached from the plant. Apparently, a reduction mechanism from dehydro to reduced ascorbic acid is active in normal tomatoes but inactive in detached rin fruits. This mechanism was operative in normal and rin fruits left on the plant. Exogenous ethylene (10 ppm) neither affected reduced ascorbic acid levels in normal and rin fruits, nor the total ascorbic acid in normal fruits. Maintenance of initial levels of total ascorbic acid was noted in ethylene treated rin fruits. Similar total ascorbic acid levels were found in normal and rin fruits held on the vine to the red and yellow stages, respectively; and were higher than in comparable fruits held in storage.
Chemical Inactivation of the Heat-tolerant Pectolytic Enzymes in Raw Apricots which Cause Softening of the Canned Product1
Authors: Sommer Noel F. , Buchanan Jack R. , Fortlage Robert J.
Published: August 2022

Pectolytic enzymes of fungal origin (mostly Rhizopus spp.) contaminating raw apricot fruits may not be completely inactivated during thermal processing (i.e., 100°C/18 minutes). The remaining enzymes may seriously macerate fruits over a 6-to-18 month period after canning. Inactivation of crude enzymes was near exponential over a 4-log-cycle reduction of activity after heating at 121°C for up to 20 minutes. Serious overcooking of fruit at elevated temperatures discouraged further studies of heat inactivation. Laboratory and cannery tests demonstrated that a dilute spray or dip of sodium hydroxide (i.e., 1n/1 minute) at ambient temperature offered an inexpensive, simple means of inactivating fungal enzymes contaminating apricot fruits. Crucial to success was accurate maintenance of solution concentration and contact times. For adequate penetration of solutions, the fruit skins over fungal lesions required breaking. Jet sprays broke the skin over the Rhizopus softrot lesions if they contacted all fruit surfaces.
Derivation of Matroclinal Diploids in Chinese Cabbage and Evaluation of their Significance in Breeding1
Authors: Opeña R. T. , Lo S. H.
Published: August 2022

Early generation breeding lines of Chinese cabbage (Brassica campestris L., Pekinensis group) produced easily discernible matroclinal diploids in crosses with radish (Raphanus sativus L.). Heterozygosity for a single gene marker among a number of these maternally derived plants precluded post-meiotic doubling or fusion of haploid nuclei within the same embryo sac followed by parthenogenesis as their modes of origin. Selfed progenies descended from matroclinous plants were also observed to be relatively more variable for metrical characters than related conventional inbreds. The matroclinal diploids examined in this experiment were therefore heterozygous. Consideration of this and other limitations led to the conclusion that these plants as well as the system to secure them do not have any direct useful application in Chinese cabbage breeding.
A Synoptic Analysis of Peach and Cherry Flower Bud Hardiness1
Authors: Proebsting E. L. , Mills H. H.
Published: August 2022

Flower buds from 10 ‘Bing’ cherry (Prunus avium L.) and 5 ‘Elberta’ peach (Prunus persica [L.] Batsch) orchards were tested for cold resistance each week for 3 years during the dormant and pre-bloom periods. The cold resistance of dormant buds was most affected by temperature prior to sampling. Additionally, buds from certain sites were consistently more resistant than buds from others. Elevation, soil type, and cultural practices are the site characteristics likely to influence cold resistance of buds. During the pre-bloom period differences among sites were closely related to bud development which, in turn, was associated with elevation and temperature.
Pectin and Related Constituents in Avocado Fruit During Ontogeny1
Authors: Eaks Irving L. , Sinclair Walton B.
Published: August 2022

Pectic substances in 4 avocado cultivars were determined as anhydrouronic acid (AUA) during ontogeny and related to fruit maturity, alcohol-insoluble solids (AIS), alcohol-soluble solids (ASS), ASS minus oil, total oil, fresh weight and dry weight. The concentration of pectic substances in avocado pulp varied among different cultivars and increases during growth and maturation. AUA varied between 0.7 to 1.5% on a fresh weight basis. However, values on a dry weight basis are relatively constant at about 5.0% and independent of the state of maturity or cultivar. AIS, ASS, alcohol-soluble acid and oil increase as the fruit mature, ASS minus oil and water content decreased during the growth and maturation periods. Changes in oil content during ontogeny was the only constituent of those examined which was related to maturity.
Distinguishing Apple Clones and Cultivars by Surface Morphology and Pollen Physiology
Authors: Marcucci M. Clara , Sansavini S. , Ciampolini F. , Cresti M.
Published: August 2022

Pollen grains of 31 cultivars of apple (Malus domestica Borkh.), including 13 “standard” and “spur” clones, were examined using scanning electron microscopy (SEM) and some physiological characters (germination, pollen tube length, and viability) for identification purposes. Sizes and shape of pollen were quite uniform within a given cultivar. The differences in the exine pattern may help for the identification of some cultivar, or of groups of genetically close cultivars. Size and number of the pits made the separation of some cultivars from others possible while slight differences in the ridge pattern and the physiological characters (viability and germination) were useful traits to discriminate standard from spur types within a given polyclonal cultivar.
Color and Composition of Highbush Blueberry Cultivars
Authors: Sapers Gerald M. , Burgher Anita M. , Phillips John G. , Jones Susan B. , Stone Eric G.
Published: August 2022

The anthocyanin content of ripe berry samples of 11 cultivars of highbush blueberry (Vaccinium corymbosurn L.) varied over a 3-fold range. HPLC separation of individual anthocyanins in blueberry samples revealed 3 distinct anthocyanin patterns. Visible absorption spectra of aqueous berry extracts reflected differences in anthocyanin concentration and pH, the latter especially being evident with the more acidic berries of ‘Coville’ and ‘Elliott’. Tristimulus reflectance measurements made on whole berries correlated with visual assessment of waxy bloom but not with anthocyanin content, anthocyanin pattern, or juice pH. SEM examination revealed 2 different surface structures in samples exhibiting bloom. Tristimulus parameters for blueberry juice were dependent on anthocyanin concentration, pH, and the occurrence of browning, but not on the pattern of individual anthocyanins.
Tomato Growth as Affected by Root-zone Temperature and the Addition of Gibberellic Acid and Kinetin to Nutrient Solutions
Authors: Bugbee Bruce , White John W.
Published: August 2022

The effect of root-zone temperature on young tomato plants (Ly copersicon esculentum Mill. cv. Heinz 1350) was evaluated in controlled environments using a recirculating solution culture system. Growth rates were measured at root-zone temperatures of 15°, 20°, 25°, and 30°C in a near optimum foliar environment. Optimum growth occurred at 25° to 30° during the first 4 weeks of growth and 20° to 25° during the 5th and 6th weeks. Growth was severely restricted at 15°. Four concentrations of gibberellic acid (GA3) and kinetin were added to the nutrient solution in a separate trial; root-zone temperature was maintained at 15° and 25°. Addition of 15 μm GA3 to solutions increased specific leaf area, total leaf area, and dry weight production of plants in both temperature treatments. GA3-induced growth stimulation was greater at 15° than at 25°. GA3 may promote growth by increasing leaf area, enhancing photosynthesis per unit leaf area, or both. Kinetin was not useful in promoting growth at either temperature.
Effects of Vesicular−Arbuscular Mycorrhizae and Phosphorus on Apple Seedlings
Authors: Geddeda Yosef I. , Trappe J. M. , Stebbins R. L.
Published: August 2022

Mycorrhizal fungal inoculation of seedlings of apple (Malus domestica Borkh.) substituted for P application in soils deficient in P. Of 3 mycorrhizal species, Gigaspora margarita Becker & Hall was the least effective in promoting plant growth, Glomus fasciculatum (Thaxter sensu Gerdemann) Gerd. & Trappe was the most effective, and Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe was intermediate. Combining the 3 species was no more effective than G. fasciculatum alone. VA mycorrhizae increased leaf P concentration in apple leaves from 0.04% to 0.19% on Parkdale soil which had an exchangeable P content of 13 ppm.
Ammonium Injury to Poinsettia: Effects of NH4-N:N03-N Ratio and pH Control in Solution Culture on Growth, N Absorption, and N Utilization
Authors: Cox Douglas A. , Seeley John G.
Published: August 2022

Poinsettia (Euphorbia pulcherrima Willd. ex Klotz) was grown in unbuffered nutrient solutions varying in proportion of NH4-N:NO3-N at 50 ppm N. Reductions in shoot and root dry weight and subseqeunt NH4-N absorption, accompanied by the increase in solution acidity with initial NH4-N absorption, occurred with 75% and 100% NH4-N treatments, as compared to treatments of 50%, 25%, or 0% NH4-N. Depression of NH4-N absorption with 100% NH4-N treatment caused a reduction to the critical level of total reduced N in the upper leaves and the appearance of N-deficiency symptoms. Characteristic symptoms of NH4-N injury to plants—large increases in tissue NH4-N and soluble organic N, leaf interveinal chlorosis, and marginal necrosis—did not occur in any treatment. In a second experiment, CaCO3 added to the 100% NH4-N solution at 0, 88, 176, or 264 mg/liter resulted in varying degrees of pH control. Some increase in shoot and root dry weight occurred at 88 and 176 mg CaCO3/liter; CaCO3 at all rates greatly increased NH4-N absorption compared to 0 mg CaCO3/liter, and increased total reduced N in the leaves and roots. Lower leaves of plants with CaCO3 displayed symptoms of NH4-N injury and significant accumulations of NH4- N and soluble organic N. The detrimental effects of NH4-N on poinsettia appear to be dependent on the degree of pH control in the root medium and its effects on root growth and NH4-N absorption and utilization.
An Optical Method for Estimating Papaya Maturity
Authors: Birth G. S. , Dull G. G. , Magee J. B. , Chan H. T. , Cavaletto C. G.
Published: August 2022

Body transmittance spectroscopy and analytical measurements of chlorophyll, carotenoids, and soluble solids concentrations were used to develop a nondestructive technique for estimating the maturity of papayas (Carica papaya L.). Optical measurements were taken between 500−900 nm with a scanning monochromator and a tilting-filter, abridged monochromator. Immature and mature-green fruit which were indistinguishable by visual examination could be separated by body transmittance spectroscopy into nonripening and ripening groups.
The Effect of Temperature and Polyethylene Glycol-induced Osmotic Stress on Radicle Growth of Lespedeza stipulacea, Lolium multiflorum, and Bouteloua curtipendula
Authors: Masiunas J. B. , Carpenter P. L.
Published: August 2022

Seedlings of Lolium multiflorum Lam., Lespedeza stipulacea Maxim., and Buteloua curtipendula (Michx.) Torr. were grown for 48 hours in darkness at constant temperatures of 22°, 27°, 32°, or 37°C either in distilled water or polyethylene glycol 20,000 (PEG) solutions with osmotic potentials of −3.2, −7.7, and −9.8 bars. Redicle growth rate decreased as concentrations of polyethylene glycol increased. Radicle growth was reduced at 32° and negligible at 37° for L. multiflorum. All levels of PEG-induced osmotic stress reduced radicle growth at 22° and 32°, while at 27° only higher levels reduced growth of L. multiflorum. PEG-induced osmotic stress reduced radicle growth of B. curtipendula significantly at all temperatures except 37°, where the lowest level of PEG had an insignificant effect on radicle growth. With L. stipulacea, low levels of PEG-induced osmotic stress did not have a significant effect on radicle growth, but an osmotic stress of −9 bars reduced growth at all temperatures.