bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenolic Compounds in Foliage of Commercial Tomato Cultivars as Growth Inhibitors to the Fruitworm, Heliothis Zea1
Authors: Isman M. B. , Duffey S. S.
Published: August 2022

Semi-purifled extracts of phenolics from foliage of tomato (Lycopersicon esculentum Mill.) inhibit larval growth of the fruitworm, Heliothis zea (Boddie), when added to artificial diets for this insect pest. The degree of inhibition of growth (dose-response) is directly related to the quantity of total phenolics in extracts added to diets, whether the extracts are of equivalent amounts of foliage from different cultivars or of foliage pooled from several cultivars added in serial dilution. Dose-responses for extracts were equal to those obtained with pure chlorogenic acid or rutin, major phenolic constituents of tomato foliage. Also, equivalent quantities of phenolics from 5 different cultivars inhibited larval growth equally when added to diets. These 3 sets of observations show that isolated tomato foliar phenolics affect H. zea larvae quantitatively, with no measurable qualitative differences between cultivars. When 2nd instar larvae were reared on excised leaflets from several cultivars of field-grown tomatoes, significant differences in larval growth between cultivars were obtained, which were consistent through two years. However, significant relationships between foliar phenolic content and larval growth were not obtained, partially because of the highly variable nature of phenolic content within and between plants. Our results suggest that phenolics in tomato foliage at the minimum contribute a substantial background level of antibiosis to H. zea.
Light Penetration on Overcast and Clear Days, and Specific Leaf Weight in Apple Trees as Affected by Summer or Dormant Pruning1
Authors: Marini Richard P. , Barden John A.
Published: August 2022

Summer pruning of vigorous ‘Starking Delicious’ apple (Malus domestica Borkh.) trees in mid-August (14 weeks after bloom) increased light penetration throughout the tree canopy for the remainder of the season. Light levels were lower in summer pruned trees than in similarly dormant pruned control trees the season following treatment. Relative light penetration measured with a selenium cell on clear days was similar to diffuse light penetration measured with a quantum sensor on overcast days until late summer. During late summer, when the developing fruit caused the branches to spread, diffuse light penetration on overcast days was greater than the penetration of direct light on clear days. Reduced light penetration the year following summer pruning resulted in lower specific leaf weight (SLW) of interior leaves as compared to interior leaves on dormant pruned trees. Specific leaf weight of peripheral leaves on dormant pruned trees declined in October, while SLW of leaves on summer pruned trees did not decline. The delayed decline in SLW may have been due to improved light conditions and/or delayed leaf senescence. Regardless of treatment, SLW of interior leaves did not decline in October.
Carbohydrates and Fatty Acids in Developing Pecan Fruit1
Authors: Wood B. W. , McMeans J. L.
Published: August 2022

Sugars and fatty acids were measured during fruit development of ‘Moneymaker’ pecan [Carya illinoensis (Wang.)] Koch. Major sugars in the kernel, shell, and shuck were fructose, glucose, sucrose, and inositol; major fatty acids were oleate, linoleate, palmitate, linolenate, stearate, myristate, margarate, and arachidate. During endosperm expansion fructose and glucose rapidly accumulated and fatty acids were present in small concentrations. During embryo and cotyledon expansion fatty acids accumulated and reducing sugars and inositol declined while sucrose increased.
Effect of the Fruit-ripening Mutant Genes rin and nor on the Flavor of Tomato Fruit1,2
Authors: Kopeliovitch E. , Mizrahi Y. , Rabinowitch H. D. , Kedar N.
Published: August 2022

Organoleptic tests of the non-ripening tomato mutants rin and nor and their F1 hybrids with the normal-fruit-bearing cultivar ‘Rutgers’ indicated that fruits of the rin heterozygous plants (rin/+) were slightly inferior and that those of inferior in flavor to fruits of the normal genotype (+/+), all sampled 3–5 days after ethylene and CO2 evolution rates attained maximum levels. The flavor of fruits of the double heterozygote nor heterozygotes (nor/+) were distinctly rin/+, nor/+ was poorer than either of the 2 single-gene heterozygotes, while fruits of both homozygous plants, nor/nor and rin/rin, were unpalatable. Analyses of pH, titratable acidity, total soluble solids, and reducing sugars did not indicate that any of these parameters is responsible for the inferior flavor of the genotypes containing the non-ripening genes. Comparisons of reciprocal crosses provided no evidence of cytoplasmic inheritance of fruit flavor.
Effect of Mepiquat Chloride on the Growth and Yield of ‘Concord’ Grapevines1
Authors: Pool R. M.
Published: August 2022

Mepiquat chloride (MP-Cl) applied at the late prebloom stage or during bloom increased the set and yield of ‘Concord’ grape (Vitis labruscana Bailey) and restricted length of pre-existing but not yet fully expanded internodes, but not those formed subsequent to treatment. Unlike most growth retardants, MP-Cl appears to exert its effect directly on the developing flowers rather than via vegetative growth control.
Absorption of 14CO2 by Potato Roots and its Subsequent Translocation1
Authors: Arteca Richard N. , Poovaiah B. W.
Published: August 2022

Root systems of potato plants (Solanum tuberosum L. var. Russett Burbank) were treated with 14CO2 and translocation was evaluated by autoradiography. Treatments of less than 1 hour showed little radioactivity in the leaves. Between 1 and 6 hours, there was a substantial increase in radioactivity in both roots and leaves. The 14CO2 was translocated to the leaves as 14CO2 dissolved in the xylem sap and as components fixed in the roots then transported. Plant tissues were analyzed spearately for radioactivity as extractable, basic (amino acids), neutral (sugars), insoluble (starch), and acidic (organic acids and sugar phosphates) fractions. Between 70 and 80% of the total extractable radioactivity was in the acidic fraction; of this, 96% was found in malic acid with the remainder containing other organic acids, amino acids, and sugars.
Effect of Oryzalin and Other Herbicide Treatments on Selected Quality Factors of Sweet Potatoes1
Authors: Hammett Larry K. , Monaco Thomas J.
Published: August 2022

Oryzalin (3,5-dinitro N4, N4-dipropylsulfanilamide), oryzalin/chloramben (3-amino-2,5-dichlorobenzoic acid) combinations, and diphenamid (N,N-dimethyl-2,2-diphenylacetamide) were evaluated for their influence on root quality of sweet potato [Ipomoea batatas (L.) Lam.] at harvest and during storage. Mineral analysis and foliage dry matter were evaluated with no significant differences observed between the oryzalin rates, diphenamid, and the controls. Soluble carbohydrates, reducing carbohydrates, ascorbic acid, and carotene content were not influenced by the herbicidal treatments. Intercellular space values were all within an acceptable range at harvest storage. The 3 rates of oryzalin utilized were not detrimental to quality and comparable to the diphenamid, weedy control, and cultivated control treatments.
Incidence and Severity of Chilling Induced Internal Browning of Waxed ‘Smooth Cayenne’ Pineapple1
Authors: Rohrbach Kenneth G. , Paull Robert E.
Published: August 2022

Waxing the fruit and crown of fresh pineapple [Ananas comosus (L.) Merr.] with a 20% v/v paraffin-polyethylene: water mixture reduced the incidence and severity of internal browning caused by chilling injury to 15% and 31%, respectively, of the unwaxed control. Symptom incidence in waxed fruit was not affected by fruit maturity at harvest. Increasing wax:water emulsion concentration up to 50% v/v further decreased symptom incidence and severity with the greater suppression occurring with less than 20% v/v. Crown leaves were extremely susceptible to chilling injury; they turned grey and became desiccated following 8°C storage. Waxing did not affect these symptoms. Waxing assisted in retaining fruit shell appearance and reduced the rate of shell degreening by 60%. The major changes in internal browning and fruit external appearance occurred during holding at room temperature following 8° storage. Varying wax composition with polyethylene and pH had no significant effect on fruit characteristics.
Effects of Virus Infection on Nitrogen Fixation in Cowpea [Vigna unguiculata (L.) Walp]1
Authors: O’Hair S. K. , Miller J. C.
Published: August 2022

The effects of the cowpea strains of southern bean mosaic (SBMV-CS), cucumber mosaic (CMV-CS), and tobacco mosaic (TMV-CS) viruses on cowpea [Vigna unguiculata (L.) Walp] plant growth and N fixation parameters were evaluated in greenhouse and field experiments. TMV-CS infection resulted in the most severe symptoms and was associated with significant reductions in nitrogenase activity, total nodule weight, nodule number, and plant dry weight, in susceptible cultivars. Infection with CMV-CS was associated with significant reductions in nitrogenase activity, nodule number, and plant dry weight in field-grown ‘Mississippi Silver’. SBMV-CS infection was least severe and was associated with a significant reduction in nitrogenase activity and nodule weight in only 1 susceptible cultivar under field conditions.
Identification of Resistance to Amphorophora agathonica in the Native North American Red Raspberry1
Authors: Daubeny Hugh A. , Stary Dana
Published: August 2022

Seedlings from 21 collections of the native North American red raspberry, Rubus idaeus strigosus (Michx.), were screened for reaction to Amphorophora agathonica Hottes, the aphid vector of the red raspberry mosaic virus complex. Sixty-four seedlings from 1,041 screened were selected for resistance to colonization. Three of these were intercrossed and also crossed with 2 cultivars of R, i. vulgatus Arrhen origin to produce F1 progenies. Inheritance of the resistance reaction in the 3 selected seedlings appeared to be controlled by 2 dominant complementary genes. These genes, which are designated Ag2 Ag3, do not appear to give as high a level of resistance to the aphid as gene Ag1, which is of R. i. vulgatus origin and gives virtual immunity. It is suggested that genotypes combining Ag, with Ag2 and Ag3 might be of value in reducing genetic vulnerability if virulent biotypes of A. agathonica appear. Screening for reaction to the aphid under laboratory conditions, prior to field planting, eliminated large numbers of susceptible seedlings. Additional screening in the field the year of planting eliminated more. Segregation ratios, which had been adjusted from the field results, gave better agreements than laboratory screenings alone to the proposed hypotheses.
Comparative Growth of Chrysanthemums at Different Night Temperatures1
Authors: Parups E. V. , Butler G.
Published: August 2022

Several cultivars of spray and standard chrysanthemums (Chrysanthemum morifolium Ramat.) were grown at normal (16°C) or split (16° and 10°) night temperature during the short-day growth period. The overall growth, number of blooms and buds, and weight of blooms were increased by the split night temperature treatment. Many growth parameter means, except leaf area ratio (LAR) and leaf weight ratio (LWR), were higher when the plants were grown at the split night temperature. Most growth parameters, except specific leaf area (SLA), were affected significantly by either temperature treatments or cultivar differences and harvest times. The data indicate that the split night temperature treatment was beneficial to the growth of some and not detrimental to the growth of other cultivars of chrysanthemums.
Yield Response of Staked, Fresh-market Tomatoes to Reduced Use of Fertilizers and Insecticides1
Authors: Csizinszky A. A. , Schuster D. J.
Published: August 2022

Response of tomatoes, Lycopersicon esculentum Mill., cv. Flora-Dade, to insecticides applied weekly or on demand and to 3 fertilizer levels, low (1 ×), medium (2 ×), and high (3 ×), was investigated in fall 1979 and spring 1980. Insecticide spray schedules had no effect on fruit size, marketable yield, and number of fruit per ha. The application of fertilizers above the 1 × level (148 kg/ha N, 30 P, 171 K, and 10 Mg) did not improve fruit size or increase tomato yields, but increased residual salt content of soil.
Inheritance of Differences in Calcium Utilization by Tomatoes under Low-calcium Stress1
Authors: Giordano Leonardo de B. , Gabelman W. H. , Gerloff G. C.
Published: August 2022

Differential plant response to Ca-deficiency stress was investigated by screening 138 tomato lines (Lycopersicon esculentum Mill.) in nutrient solution at 10 mg of Ca per plant. Dry weight produced during vegetative growth and severity of Ca-deficiency symptoms were used to classify plants as efficient and inefficient. Efficiency in Ca utilization within the plant was defined and expressed as the mg of dry weight produced for each mg of Ca absorbed by a plant (CaER). Three of the most efficient and 3 of the most inefficient lines were selected for additional studies. The efficient lines produced an average of 81% more dry weight than the inefficient lines at 10 mg of Ca. Comparable amounts of dry weight were produced by all lines at 400 mg of Ca per plant. Two factors were responsible for greater dry weight production under Ca-deficiency stress: more efficient utilization of tissue Ca and greater ability to absorb Ca from low-Ca solutions. Inheritance studies indicated that additive gene effects made major contributions to variations in response to low Ca. A simple additive-dominance model was adequate to explain differences in CaER, with additive effects highly significant. Some interallelic interactions appear to be important for total plant dry weight inheritance.
Physiological and Nutritive Effects of K-Pretreatment and KCl Sprays on Water-stressed and Unstressed Apple Seedlings1
Authors: Swietlik Dariusz , Korcak R. F. , Faust Miklos
Published: August 2022

Low- and high-K pretreated ‘York Imperial’ apple seedlings (Malus domestica Borkh.) were grown in nutrient solution cultures. Addition of polyethylene glycol (PEG) to the nutrient solution to reduce water potential to −1.0 bar reduced water consumption, fresh weight, specific leaf weight (SLW), and leaf water potential and increased the amount of water consumed per unit of fresh weight gain. High-K pretreatment increased water consumption of unstressed seedlings but decreased water consumption of PEG-stressed plants. Daily sprays with 0.5% KCl applied in early afternoon had no effect on water consumption rate in apple seedlings. However, sprays probably induced wider stomatal opening, since K-sprayed trees had lower leaf water potential when measured at noon than unsprayed trees. This effect was not observed when water potential was measured in the morning (0800 hr). High-K plants had higher leaf water potential than low-K plants in the morning. Potassium pretreatment and PEG stress as well as K-sprays had numerous effects on plant mineral composition. The K-pretreatment or K-sprays did not alleviate the detrimental effects of PEG-induced water stress despite the effects of K-pretreatment and K-sprays on mineral composition and leaf water potential.
Metabolism of an Ethylene-releasing Growth Regulator (CGA-15281) in Young Peach Fruit1
Authors: Seeley Schuyler D. , Couvillon Gary A. , Kays Stanley J.
Published: August 2022

CGA-15281, (2-chloroethyl)methylbis(phenylmethoxy)silane (CGA), labeled with [14C] in the chloroethyl or methyl or methoxy position, was applied, as an aqueous spray or by syringe subepidermally into an aqueous film, to peach[Prunus persica (L.) Batsch cv. Bicentennial] fruitlets to label and trace metabolites. Hexane and methanol extractions followed by thin-layer chromatography revealed a minimum of 3 metabolites in the hexane fraction and 2 metabolites in the methanol fraction. Ion exchange, silica gel, and gas liquid chromatography (GLC) were used to purify metabolites. Benzyl alcohol, benzylglucoside, benzylmethylglucoside, and a CGA impurity were isolated and identified by GLC-mass spectroscopy. CGA metabolism was rapid. After 35 days, 98.9% of the original [14C], from the chloroethyl position, could be accounted for: 89% as ethylene, 0.22% as CO2, 0.32% as structural carbohydrates, and 9.04% in extractable residue. Substantially lower recoveries were obtained when the molecule was labeled in the methoxy or methyl position, due to volatilzation and/or breakdown and volatilization of these molecular segments. Headspace analysis showed similar volatile hydrocarbons (e.g., methane, ethane, ethylene, propylene, butane, and benzyl alcohol) as found in the headspace over benzyl alcohol. Less than 1% of the methyl or methoxy label was given off as [14C] ethylene. Evolved 14CO2 accounted for less than 0.5% of the label applied with each of the labeling positions.
Structure of Cytoplasmic Male-sterile and Fertile Carrot Flowers1
Authors: Erickson E. H. , Garment M. B. , Peterson C. E.
Published: August 2022

Examination of flowers of carrot (Daucus carota L.) using the scanning electron microscope revealed that some cytoplasmically male-sterile genotypes exhibit flower abnormalities that may be associated with reduced pollination and seed set. Such abnormalities, evident in many inbred lines, may carry over to the male-sterile F1 parents used to produce 3-way hybrids and probably affect insect pollinator activity.
Endomycorrhizae of Vaccinium corymbosum L. in North Carolina1
Authors: Boyer E. P. , Ballington J. R. , Mainland C. M.
Published: August 2022

Ericoid mycorrhizae were measured on roots of wild and cultivated highbush blueberries (Vaccinium corymbosum L.) from 7 locations in southeastern North Carolina over 4 sampling dates. An adequate clearing and staining procedure was developed specifically for observing endomycorrhizae in blueberry roots. Abundant mycorrhizae were found in wild blueberry plants, but few mycorrhizae were noted in cultivated plants. Phosphorus levels were lower in the wild than in the cultivated blueberry soils at most locations.
Light Acclimatization Potential of Ficus benjamina1
Authors: Fails Barbara S. , Lewis A. J. , Barden J. A.
Published: August 2022

Weeping Hg (Ficus benjamina L.) plants grown under 3 light regimes (full sun, full sun followed by 8 weeks acclimatization under 75% shade, and 75% shade) were placed in a low-light simulated interior environment (SIE) for 12 weeks. Acclimatized and shade-grown leaves had higher net photosynthesis (Pn) rates, lower dark respiration (Rd) rates, and lower light compensation points (LCP) than sun-grown leaves after 12 weeks in the SIE. No treatments increased total plant dry weight during the 12 weeks of SIE. However, percent dry matter of sun plants was redistributed with additional leaves produced at the expense of root carbohydrate reserves. Leaf production exceeded abscission in all treatments. Anatomical observations prior to and following the SIE indicated chloroplast reorientation in all treatments. The development of large, heavily stained chloroplasts suggest ultrastructural changes may also occur as a result of low light.
Unilateral Incompatibility between Red and Black Raspberries1
Authors: Hellman E. W. , Skirvin R. M. , Otterbacher A. G.
Published: August 2022

The discrepancy in seed set observed in reciprocal crosses of red (Rubus idaeus L.) and black (R. occidentals L.) raspberries verifies unilateral incompatibility. The strength of the incompatibility varies between cultivars; some red × black crosses yield a small percentage of seed set by simple cross-pollination, while others produce almost no seed. Although black cultivars have shorter pistils than red cultivars, the role of this factor in incompatibility is unknown. Bud pollination and heat treatments increased seed set in some normally incompatible red × black crosses.
The Effect of Soil Moisture Stress to Various Fractions of the Root System on Transpiration, Photosynthesis, and Internal Water Relations of Peach Seedlings1
Authors: Tan C. S. , Buttery B. R.
Published: August 2022

Peach [Prunus persica (L.) Batsch] seedlings were grown in large sectional boxes with root systems divided into 4 separate quadrants. Groups of peach seedlings with 3, 2, 1, and 0 quadrants of the root system deprived of water for 3 weeks, were further subjected to moisture stress in all quadrants by withholding water for 5 days, and they were then rewatered. In another treatment, seedlings were subjected to 2 cycles of water stress, applied 3 weeks apart, by completely depriving all quadrants of water until the plants wilted. Transpiration, photosynthesis, stomatal conductance, and xylem pressure potential were measured. Subjecting a large portion of the root (50%) to stress by withholding water only caused a small reduction (17%) in transpiration, photosynthesis, and stomatal conductance. Subjection of various fractions of the root system to severe moisture stress did not affect the shoot:root ratio. The reduction in root growth in dry quadrants was accompanied by the production of more roots in wet quadrants and less transpiring leaf surface and branch growth. The rate of recovery of transpiration and photosynthesis from water stress was greatly influenced by the duration and intensity of wilting as well as by the rate of regeneration of new root systems.
The Role of Nitidulid Beetles in Natural Pollination of Annona in Israel1
Authors: Gazit Shmuel , Galon Israel , Podoler Haggai
Published: August 2022

Four species of beetles of the family Nitidulidae were the most common arthropod visitors to flowers of annona (Annona sp.) in Israel throughout the flowering season and a significant relationship was demonstrated between these beetles and fruit-set. The beetles carry annona pollen on their dense cover of hairs. No difference in the efficiency of the 4 species was detected. The number of beetles per flower affected the fruit quality and shape.
The Effect of Reduced Water Supply on Peach Tree Growth and Yields1
Authors: Mitchell P. D. , Chalmers D. J.
Published: August 2022

A range of irrigation levels was compared in specific periods of fruit development to determine their suitability for control of tree vigor and yields in ultra-dense orchards of peach [Prunus persica L. Batsch] trees. Where trees in the 3rd leaf were trickle-irrigated with 4 levels (100, 50, 25, and 12.5%) of replacement of Eps (evaporation over the planting square) during the period of rapid vegetative growth, both frame and fruit growth declined as irrigation quantity decreased. In the following period of maximum fruit growth, 130% of Eps replacement increased vegetative growth but not fruit growth compared to 100% Eps. The fruit, however, grew faster in this period on those trees which had received low levels of Eps replacement in the earlier period of maximum vegetative growth. The net result was similar final fruit size and yield between treatments, combined with control of vegetative growth at the lower levels of Eps. A large saving in irrigation water was obtained at the lower levels of replacement of Eps.
Effects of Metalaxyl on Phycornyceteous Fungi and Yield of Pepper, Tomato, and Cabbage Transplants1
Authors: Jaworski C. A. , Phatak S. C. , Csinos Alex
Published: August 2022

Metalaxyl [N-(2,6-dimethyphenyl-N-(methoxyacetyl)-alanine methylester] was applied at 0 and 1.12 kg (active ingredient)/ha immediately after seeding pepper (Capsicum annuum L.), tomato (Lycopersicon esculentum Mill.), and cabbage (Brassica oleracea L. Capitata group) in nonfumigated, plastic-covered nonfumigated, and fumigated Fuquay loamy sand. Metalaxyl increased marketable pepper transplant yields by 93%, increased plant stands by 13%, increased fresh weight by 22%, and significantly reduced Pythium loci. Size of pepper transplants was increased more by metalaxyl application to fumigated than nonfumigated soils. Metalaxyl increased marketable tomato transplant yield by 19%, while the plant size was not affected. Metalaxyl did not affect cabbage transplant yields, but size of marketable transplants was increased by 25% and downy mildew (Peronospora parasitica Yerkes & Shaw) infection was significantly reduced. Soil populations of Pythium spp. were reduced significantly with metalaxyl in the nonfumigated and plastic-covered nonfumigated treatments for the three crops.
Soil Compaction Effects on Nitrogen Use in Tall Fescue1
Authors: Sills M. J. , Carrow R. N.
Published: August 2022

Tall fescue (Festuca arundinacea Schreb. ‘Kentucky 31’) was subjected to 3 compaction treatments with 2 nitrogen levels. Increasing compaction increased bulk density, water retention, and soil strength while aeration porosity decreased. Visual quality, clipping yield, N use per unit soil area, and root growth declined as compaction increased. Compaction reduced percent N recovery by 10 to 31% compared to uncompacted plots. Visual quality, clipping yield, percent N in leaf tissue, and N uptake increased with increasing N-rates but percent N recovery declined. Total nonstructural carbohydrates were unaffected. The high N-rate with compaction had a detrimental effect on root growth.
Ozone Sensitivity of Woody Plants: Modification by Ethylenediurea1
Authors: Cathey H. M. , Heggestad H. E.
Published: August 2022

Seedlings of 13 species of woody plants were sprayed or their growing media was drenched with N-2-(2-oxo-l-imidazolidinyl) ethyl-N'-phenylurea (EDU). The chemical provided protection against fumigations with 0.2, 0.4, and 0.6 or 0.35, 0.55, 0.75, and 0.95 ppm ozone (O3) for 3 hr. EDU reduced or prevented O3-induced necrotic flecking, bronzing, and premature aging of sensitive leaves of Acer rubrum L., Be tula papyrifera Marsh, Fraxinus americana L., Gleditsia triacanthos L., Koelreuteria paniculata Laxm., Plantanus × acerifolia (Aid.) Willd., Syringa vulgaris L., and Tilia cordata Mill. Drench of the growing media was a more effective method of applying EDU than a foliar spray application. An elapsed time of 7 days between applications of EDU and 03 exposure increased significantly the effectiveness of the chemical. We observed no other physiological effects from application of EDU on the growth of the plants. Seedlings of Cedrus deodora (D. Don) G. Don, Cornus florida L. and Pinus strobus L., were quite insensitive to O3 so the effectiveness of EDU on them was difficult to evaluate. Seedlings of Paulownia tomentosa Steud. and Quercus alba L. exhibited little or no visible injury from the fumigations with O3.
Role of Light Quality, Photoperiod, and High-intensity Supplemental Lighting on Flowering of Alstroemeria ‘Regina’1
Authors: Healy W. E. , Wilkins H. F. , Celusta M.
Published: August 2022

Alstroemeria L. ‘Regina’ plants grown at 22°C did not flower, regardless of photoperiod treatments. If grown at 13°, plants flowered sooner under long photoperiod treatments than under natural days (ND). Incandescent (Inc) or red light treatments applied as a night interruption (NI) promoted earlier flowering than NI-far-red, ND, or short days (SD). Number of flowering shoots was unaffected by light quality. Plants grown under SD treatments produced the fewest flowering shoots. Flower production was related to early commencement and subsequent duration of the flowering span, as all plants ceased flowering on similar dates. When plants were rotated every 20, 30, or 40 days between SD and NI-Inc light treatments, the days to flower were delayed compared to plants grown continuously (nonrotated) under NI-Inc. Nevertheless, plants which were rotated between the various SD and NI-Inc light treatments flowered sooner than plants under continuous SD. Days to flower were reduced when plants were transferred monthly (December to June) from SD to either ND, 20 hr Inc, or 10 or 20 hr of high-intensity discharge (HID) lights. Flowering was hastened by 20 hr of HID lighting when compared to Inc during the months when the natural photoperiod was less than 12 hr, but had no influence when the 20-HID light treatment commenced after the natural photoperiod was greater than 12 hr. Maintaining plants under SD past January delayed the start of flowering, regardless of subsequent light treatments.
Fertilization, Incorporated Organic Matter, and Early Growth of Rabbiteye Blueberries1
Authors: Spiers James M.
Published: August 2022

The effect of incorporated sphagnum peatmoss and minimal fertilization on the establishment and subsequent growth of rabbiteye blueberries (Vaccinium ashei Reade) was determined in 4 field studies conducted on typical fine sandy loam, upland mineral soils in south Mississippi. Incorporated peatmoss increased plant vigor, plant height, shoot weight, leaf chlorophyll level, and fruit yield and reduced chlorosis symptoms. First- and second-year plant growth and second-year fruit yields were reduced by either slow-release or fast-release granulated fertilizer. Soluble fertilizers produced less plant damage than granulated fertilizers but no more plant growth than no fertilization. There was a close association between over-fertilization and cholorosis symptoms.
Influence of Peroxidase and Polyphenol Oxidase on the Color of Puree from Machine-harvested Strawberries1
Authors: Spayd S. E. , Morris J. R. , Robert C. L.
Published: August 2022

Horseradish peroxidase (PO) and mushroom polyphenol oxidase (PPO) were added to strawberry purees from ‘Cardinal’ and Arkansas breeding-line 5344 to determine their influence on color during 48 hours at 30°C. Neither enzyme affected strawberry puree color or phenolic content. PO activity was reduced to near zero 24 hours after addition and PPO activity was undetectable 1 hour after addition to puree. Aeration did not affect anthocyanin and flavonoid concentrations, but increased discoloration and nonflavonoid concentration. Strawberry purees containing 50% immature plus 50% ripe fruits were poorer in color and had higher levels of flavonoids. As holding time at 30°C increased, puree color decreased.
Effects of AVG on Maturation, Ripening, and Storage of Apples1
Authors: Autio Wesley R. , Bramlage William J.
Published: August 2022

Aminoethoxyvinylglycine (AVG) applied to apple trees (Malus domestica Borkh.) 1 week before harvest suppressed C2H4 production and delayed C2H4 peaks of fruit kept at room temperature. Early season cultivars (‘Early McIntosh’, ‘McIntosh’) were less affected by AVG than were late-season cultivars (‘Cortland’, ‘Royal Red Delicious’). While ripening was significantly delayed, maturation of ‘Puritan’ apples, as judged by changes in firmness, peel chlorophyll concentration, percent soluble solids, flesh starch concentration, and titratable acidity, was unaffected by AVG tree-sprays applied up to 6 weeks before harvest. Addition of C2H4 to the storage atmosphere accelerated ripening of AVG-treated fruit, whereas their ripening was slowed by storage at 0°C rather than at 3.3°.
Effects of Fruiting, Pruning, and Nitrogen Fertilization on Shoot Growth of ‘Empire’ Apple Trees1
Authors: Forshey C. G.
Published: August 2022

Three fruit thinning, 2 pruning, and 2 nitrogen fertilization treatments, in factorial combination, were established in a 7-year-old orchard of ‘Empire’ apple (Malus domestica Borkh.)/Malling Merton 106. The pruning and N fertilization treatments were continued over a 4-year period; the initial fruit-thinning treatments induced significantly different bearing patterns that persisted through the 4 years and no additional thinning was done. The thinning treatments resulted in significant differences in yield, but pruning and N had little effect. Total shoot growth/tree was unaffected the first year, but large differences developed in the succeeding years. Crop load and N had major effects on shoot growth while the effect of pruning was minor. Total shoot growth was more closely related to shoot numbers than to mean shoot length and was negatively correlated with the previous year’s crop.
Relationship of Seed Number and Maturity to Berry Development, Fruit Maturation, Hormonal Changes, and Uneven Ripening of ‘Concord’ (Vitis labrusca L.) Grapes1
Authors: Cawthon D. L. , Morris J. R.
Published: August 2022

Fruits were collected on weekly intervals in 1980, beginning at fruit set (ovary shatter) and continuing through harvest. Additional samples collected at harvest in 1980 and veraison in 1981 were sorted into preveraison green, postveraison green, and ripening categories. Seed number per berry was directly related to accumulation of 14C-photosynthate, fresh weight, and dry weight. Seed number had little relationship with berry content of indoleacetic acid (IAA), abscisic acid (ABA) or percentage of acidity. Percentage of soluble solids was not affected by seed number prior to veraison, but after veraison, percentage of soluble solids and intensity of juice color were inversely related to seed number. Nonripe fruit at the time of harvest had fewer seeds per berry, and fruit containing an immature seed did not accumulate ABA or enter veraison. IAA levels were similar in ripening and nonripening fruit. IAA declined to basal levels by about 55 days after peak bloom. ABA began to increase after 65 days from peak bloom and berry changes associated with veraison occurred after 72 days.
Soil Cation and Water Distribution as Affected by NH4NO3 Applied through a Drip Irrigation System1
Authors: Edwards J. H. , Bruce R. R. , Horton B. D. , Chesness J. L. , Wehunt E. J.
Published: August 2022

‘Redglobe’ peaches [Prunus persica (L.) Batsch] were grown under drip irrigation. Applications of NH4NO3 through the irrigation system were compared with broadcast applications. Soil pH, where NH4NO3 was applied through the irrigation system, decreased in the top 30 cm from 6.2 to 3.7 pH in the zone wetted by emitters that had been in place for 2 years, and from 6.2 to 4.5 pH in the zone where emitters had been in place for 6 months. Aluminum concentration in wetted zones increased from 0.01 to 1.45 meq/100 g of soil after 2 years and from 0.02 to 0.73 meq/100 g of soil after 6 months of NH4NO3 application through drip irrigation. Soil Ca and Mg concentrations were reduced in both wetted zones, but the greatest decrease occurred in the 2-year emitter site. The addition of NH4NO3 in the irrigation water substantially reduced root growth in the vicinity of the emitters, irrigation water application, and fruit yield, because of the high A1 concentration in the wetted zone.
Phosphorus Solution Concentrations for Production of Tomato, Pepper, and Eggplant in Minesoils1
Authors: Swiader John M. , Morse Ronald D.
Published: August 2022

Phosphate-sorption isotherms were used to predict the rates of P fertilizer required to establish 6 concentrations of solution P in reclaimed minesoils. Tomato (Lycopersicon esculentum Mill.), pepper (Capsicum annuum L.), and eggplant (Solanum melongena L.) were grown during 2 successive years on the same minesoil plots, fertilized each year with sufficient P to establish the desired solution P levels. At every solution P level, the rate of fertilizer P required the second year was less than the initial year, with the relative amount needed to re-establish the solution P levels considerably reduced at the higher solution P concentrations. Optimum solution P was reached at 0.2 ppm for tomato and pepper, while eggplant required 1.6 ppm P in solution for optimum yield. Regression analysis estimated optimum levels of solution P at 1.56 ppm for eggplant and 0.28 ppm for tomato and pepper. The optimum minesoil solution P levels for each species was similar to that reported for these same crops on other soils, indicating the broad applicability of these data and the sorption isotherm method for assessing P-fertilizer requirements. Marginal leaf necrosis and yield reductions of 73–75 % occurred with tomato and pepper when solution P concentrations were increased to 2.4 ppm. Yield response at suboptimal solution P levels was greater for tomato and pepper than eggplant, suggesting that the P nutrition of the latter crop is less efficient than the former species.
Response of Blueberry Seedlings to a Range of Soil Types1
Authors: Korcak R. F. , Galletta G. J. , Draper A.
Published: August 2022

The growth and elemental composition of a range of blueberry (Vaccinium sp.) progenies was greenhousetested on 5 unmulched soils. Three of the soils, low in pH and fertility, represented the physiographic regions of the eastern United States; Coastal Plain, Piedmont, and Appalachian Highlands; also included were a high-pH, high-fertility Piedmont soil and a commercial blueberry Coastal Plain soil. Two studies, 10 and 20 weeks in duration, were made with seedlings of crosses of blueberry clones of hybrid origin. Growth was significantly higher for seedlings grown on the commercial blueberry soil in both studies. V. ashei (rabbiteye) seedlings grew significantly larger than all others when measured over all soil types in one experiment but not the other. There were no significant differences in growth among the 4 progenies when averaged over all soil types. Percent sand was positively correlated with growth while both percent silt and clay were negatively correlated with growth. Plant composition was generally within acceptable levels for Ca, Mg, K, Fe, and Zn. Plant Mn and Al, although variable, tended to be higher than reported values. Soil Mn was significantly and negatively correlated with growth. It was possible to select individual seedlings which grew well on each of the mineral soils represented in the study.
Peel and Trim Yield and Quality of Beets and Sweet Potatoes Peeled with Superheated Steam, Saturated Steam, and Lye1
Authors: Smith D. A. , Turner J. L. , Hollingsworth M. H.
Published: August 2022

Roots of sweet potato [Ipomoea batatas (L.) Lam.] and beet (Beta vulgaris L.) peeled with superheated steam, had higher peel and trim yields than did those peeled with saturated steam at the same pressure. Product recovery was greater with all steam-peeling methods than with caustic peeling. Direct injection of cold water into the partially pressurized steam atmosphere of the peeler also increased product recovery. Better color retention in processed beets was obtained from steam-peeled roots than from caustic-peeled roots.
Regrowth, Flowering, and Fruit Quality of ‘Delicious’ Apple Trees as Influenced by Summer Pruning1
Authors: Miller Stephen S.
Published: August 2022

Vigorous, young trees of ‘Topred Delicious’ apple (Malus domestica Borkh.) either dormant-pruned or left unpruned at the end of the previous season, were summer-pruned at 8, 12, 16, or 20 weeks after full bloom (WAFB) by thinning, heading, or stubbling current season to 2-year-old shoots. The amount of new growth following summer pruning (regrowth) was influenced by the date of pruning; late pruning (20 WAFB) generally produced less regrowth than earlier pruning (8 WAFB). Regrowth also varied with moisture conditions during 2 growing seasons. Severe heading or stubbing of vigorous vegetative shoots to 2 or 3 nodes resulted in flower bud initiation on some spurs produced from axillary buds on these stubs. The degree of fruit bud initiation was related to time of pruning and moisture supply. Summer pruning generally increased the percentage of sunburned fruit harvested, but there was no consistent effect on fruit size, color, flesh firmness, or soluble solids.
The Relationship of Seed Filling to Yield among Dry Beans with Differing Architectural Forms1
Authors: Izquierdo Juan A. , Hosfield G. L.
Published: August 2022

We compared 9 dry bean (Phaseolus vulgaris L.) strains characterized by the following architectures for seed filling, yield, and components of yield: small bush, tall erect bush, classic II, and architype. Small and tall erect bush are determinate in growth habit; classic II is indeterminate and produces a short vine. Architype is erect, contains 2–4 branches angled acutely upward, grows to about 75 cm, terminates in a short vine, and does not lodge at maturity. Seed dry weight vs. days after 50% flowering data were fit to a cubic polynomial to calculate the rate and duration of seed filling. Small bush produced the greatest pods/m2 of the groups, but pod set was offset by a high percentage of shriveling and seed abortion. The architype outyielded the tall erect and small bush groups by 34 and 45 %, respectively, which was due to a greater number of seeds/pod, seeds/m2, and heavier seeds. The heavy seeds of the architype compared to the bush appeared to be due to a longer filling duration, because linear seed filling rates were similar. The architype filling duration was 11.3 days compared to 5.7 and 7.0 days for small and tall erect bush, respectively. The longer architype filling duration may be associated with its ability to prolong the duration of photosynthesis. The 17% yield increase of the architype over classic II was due to improved lodging resistance through a modification of the morphology by reducing branches and narrowing the plant canopy.
Comparison of Pour-through and Saturated Pine Bark Extract N, P, K, and pH Levels1
Authors: Yeage T. H. , Wright R. D. , Donohue S. J.
Published: August 2022

The pour-through (PT) method of nutrient extraction, which involves pouring water on the container media surface and collecting the extract (leachate), was compared to the saturated soil extract (SSE) method for a 100% pine bark medium at container capacity (102% gravimetric moisture). The SSE and PT correlation coefficients, respectively, were 0.99 and 0.94 for N, 0.99 and 0.97 for P, 0.99 and 0.93 for K, and 0.99 and 0.98 for pH. As container media moisture levels increased from 50 to 102%, the PT and SSE soluble salt levels increased 1.5 and 1.6 times, respectively, while nitrate levels increased 1.7 and 1.6 times, respectively. The volume of water applied for the PT was varied from 40 to 100 ml and did not result in extraction of different levels of N, P, K, Ca, or Mg. These data indicate the PT is an alternative to the SSE for nutrient extraction from a pine bark medium.
Mineral Nutrient Content of Ilex crenata ‘Helleri’ as Influenced by Ambient Temperature1
Authors: Wright R. D. , Blazich F. A. , Cundiff J. S. , Reid J.
Published: August 2022

Rooted stem cuttings of Ilex crenata Thunb. ‘Helleri’ were grown in a series of experiments for 3 or 6 weeks at day/night temperatures ranging from 6°/2° to 26°/22°C. Percentage of tissue N increased over time at all temperatures but at progressively slower rates as temperature decreased. Temperatures of 18°/14° or less prevented visible shoot elongation, although plant dry weights increased at all temperatures. Percentage of dry weight K increased and P, Ca, Mg, Mn, and Zn decreased with time for plants grown at 10°/6°, 14°/10° and 18°/14°, whereas the total amounts of each nutrient per plant increased. Nutrient content increased at greater rates as temperature increased. Nitrogen accumulation data were used to develop a method of timing fertilizer application in the fall. The proposed procedure ensures adequate nutrient accumulation to support vigorous spring growth without jeopardizing proper cold acclimation in the fall
Dry Weight Partitioning of ‘McIntosh’ Apple Trees1
Authors: Forshey C. G. , Weires R. W. , Stanley B. H. , Seem R. C.
Published: August 2022

Eight-year-old ‘McIntosh’/Malling-Merton (MM) 106 apple trees (Malus domestica Borkh.) were sampled 5 times (dormant, full bloom, full bloom + 3 weeks, mid-July, and harvest) during the 1980 growing season. Whole trees were separated into: trunk; scaffold branches; 1-, 2-, and 3-year-old wood; spurs; new shoots; shoot and spur leaves; and blossom clusters or fruits. Total surface area and dry weight were determined for each fraction on each sampling date. Total tree dry weight at harvest was 124% greater than the dormant weight. The distribution of the accumulated dry matter was 47.8% in wood, 19.1% in leaves, and 33.1% in fruit. Leaf canopy development was complete 3 weeks after bloom. The surface area of the leaves at harvest was 13 times that of the woody tissues.
Crossability of Selected Nontuberous Solanum Species1
Authors: Attavian B. N. , Jelenkovic G. , Pollack B. L.
Published: August 2022

Reciprocal crosses of 7 selected nontuberous Solanum species, each represented by a single genotype, were performed under greenhouse conditions to assess their levels of crossability. The degree of crossability among these species was determined by fruit set, seeds per fruit, seed germination, and degree of F1 fertility. As a result of crossing these species inter se, 3 categories were established: a) species reciprocally crossable and capable of producing fully fertile F1 plants (S. gilo Raddi × S. integrifolium Poir.; S. gilo × S. nodiflorum Jacq.; S. nodiflorum × S. integrifolium); b) species unilaterally crossable (S. indicum L. × S. incanum L.; S. gilo × S. incanum; S. macrocarpon L. × 21–73); and c) species reciprocally noncrossable (S. gilo × S. indicum). Several genotypes of eggplant (S. melongena L.) were assessed for their crossability with wild species to investigate the possibility of gene transfer to improve commercial cultivars.
Initiation and Control of Sunscald Injury of Tomato Fruit1
Authors: Adegoroye Adegoke S. , Jolliffe Peter A.
Published: August 2022

Sunscald was induced by exposing fruit of tomato (Lycopersicon esculentum mill.) to intense solar radiation; similar injury was caused by radiation from incandescent lamps. Injurious radiation treatments caused fruit temperature to exceed 40°C and altered fruit respiration rates. High air temperatures enhanced injury, but exposure to 0 to 100% O2 concentrations during radiation treatments had little influence on fruit response. Infrared wavelengths (>0.7 µm) were effective in inducing injury. Tissue water may serve as an important absorber of radiant energy. Overheating of the fruit appeared to be the main cause of injury, and storage at different temperatures, photoperiods, or O2 levels did not reverse injury induced by previous irradiation.
Effects of Acid Rain on Apple Tree Productivity and Fruit Quality1
Authors: Forsline Philip L. , Musselman Robert C. , Kender Walter J. , Dee R. J.
Published: August 2022

Mature ‘McIntosh’, ‘Empire’, and ‘Golden Delicious’ apple trees (Malus domestica Borkh.) were sprayed with simulated acid rain solutions in the pH range of 2.5 to 5.5 at full bloom in 1980 and in 1981. In 1981, weekly sprays were applied at pH 2.75 and pH 3.25. Necrotic lesions developed on apple petals at pH 2.5 with slight injury appearing at pH 3.0 and pH 3.5. Apple foliage had no acid rain lesions at any of the pH levels tested. Pollen germination was reduced at pH 2.5 in ‘Empire’. Slight fruit set reduction at pH 2.5 was observed in ‘McIntosh’. The incidence of russetting on ‘Golden Delicious’ fruits was ameliorated by the presence of rain-exclusion chambers but was not affected by acid rain. With season-long sprays at pH 2.75, there was a slight delay in maturity and lower weight of ‘McIntosh’ apples. Even at the lowest pH levels no detrimental effects of simulated acid rain were found on apple tree productivity and fruit quality when measured as fruit set, seed number per fruit, and fruit size and appearance.
Physiological Differentiation of Pistillate Flowers of Pecan and Cold Requirements for their Initiation1
Authors: Amling Harry J. , Amling Karen A.
Published: August 2022

Histological examinations of forced buds of pecan [Carya illinoensis (Wang.) K. Koch] from mature trees revealed a state of physiological differentiation of pistillate flowers by early August of the year preceding their initiation, thus predisposing them to form pistillate floral primordia. Low temperature exposure was required for pistillate flower initiation. This vernalization requirement was facultative for floral cone development, but absolute for floret formation, and was evident before the onset of rest. Grafting and in vitro bud culture techniques demonstrated that events associated with floral induction are separate from changes in the bud apex induced by cold exposure.