bluuebunny/crossref_metadata_2025 huggingface dataset:
L-Arginine-containing mesoporous silica nanoparticles embedded in dental adhesive for targeting cariogenic dental biofilm
Authors: López-Ruiz Marta , Navas Francisco , Fernández-García Paloma , Martínez-Erro Samuel , Fuentes Mª Victoria , Giráldez Isabel , Ceballos Laura , Ferrer-Luque Carmen Mª , Ruiz-Linares Matilde , Morales Victoria , Sanz Raúl , García-Muñoz Rafael A.
Published: August 2022

Dental caries is the major biofilm-mediated oral disease in the world. The main treatment to restore the caries lesions consist of the use of adhesive resin composites due to their good properties. However, the progressive degradation of the adhesive in the medium term makes possible the proliferation of cariogenic bacteria allowing secondary caries to emerge. In this study, a dental adhesive incorporating a drug delivery system based on L-arginine-containing mesoporous silica nanoparticles (MSNs) was used to release this essential amino acid as a source of basicity to neutralise the harmful acidic conditions that mediate in the development of dental secondary caries. The in vitro and bacteria culture experiments proved that L-arginine was released in a sustained way from MSNs and diffused out from the dental adhesive, and effectively contributing to the reduction of the bacterial strains Streptococcus mutans and Lactobacillus casei. Furthermore, the mechanical and bonding properties of the dental adhesive did not change significantly after the incorporation of L-arginine-containing MSNs. These results are yielding glimmers of promise for the cost-effective prevention of secondary caries.
Developing Knowledge-Based System for Predominant Chicken Diseases Diagnosis, Prevention and Management
Authors: Girma Diriba , Jimma Worku , Diriba Chala
Published: August 2022

Poultry diseases remain one of the major threats to poultry production worldwide, and chicken diseases have become one of the problems that are very detrimental to chicken farmers. Therefore, it is vital to give due attention because of its impact on the health and quality of chicken production. To solve the problem, a knowledge-based system can be a powerful tool with vast potential in alleviating agricultural and medical problems. This study aims to develop a knowledge base system for diagnosing, preventing, and managing predominant chicken diseases. The Design science research method was used to develop the prototype system. The acquired knowledge was modelled and represented using a decision tree and production rules (If-Then-Action). A backward chaining algorithm was used in this study. The prototype system was tested and evaluated, including both performance of the prototype system and user acceptance. The performance comparison parameters such as precision, recall, and F-measure were used to measure the accuracy of the prototype system, and the performance was 83%. The proposed system can assist the experts in identifying the type of disease based on the chickens' symptoms. This study is significant in providing system-based help for identifying predominant chicken diseases based on their symptoms using different techniques.
Massive Multiple user MIMO Based Enhanced Spectral Efficiency with Secure Data Transmission By Deep Learning Technique in Wireless Communication Networks
Authors: Qamar Shamimul
Published: August 2022

Wireless communications' spectral efficiency (SE) and throughput can be significantly increased with 5G technology. Multiple input multiple output (MIMO) technology, which makes use of large antennas and user equipment(UE), has emerged as most significant technology in this respect. However, the 5G wireless technology's use of MIMO would result in higher circuit power consumption as well as lower energy efficiency (EE). This research proposed novel technique in enhancing the wireless communication network spectral efficiency with secure data transmission. here the spectral efficiency of the network has been enhanced using massive multiple user based multiple input- multiple output (MMU-MIMO). Data transmission of network has been carried out based on orthogonal frequency division multiplexing (OFDM). Base station essentially serves several users simultaneously utilising the same frequency in MMU-MIMO. The spectral performance of downlink MMU-MIMO is the subject under discussion in this work. Secure data transmission of the network has been carried out using Federated deep Q- neural networks. Our simulation findings show how, for various QoS constraint levels, the ideal number of scheduled users varies
Estimation of Channel for Millimeter-Wave Hybrid Massive MIMO Multimedia Systems using Sparse Bayesian Learning (SBL)
Authors: Qamar Shamimul
Published: August 2022

Hybrid precoding in millimeter-wave large MIMO systems is a critical component for lowering radio-frequency hardware costs as compared to the traditional fulldigital precoding strategy. Knowledge of channels is required for hybrid precoding. Though, estimation of the channel is problematic for the mm-Wave system because of the usage of a massive array of antenna and hybrid architecture with analog precoding. Due to the extremely directed nature of wireless propagation, wireless channels have spatial sparsity. This spatial sparsity in wireless channel is exploited in this paper to develop a new Sparse Bayesian learning (SBL)-based massive MIMO channel estimate scheme for hybrid millimetre-wave wireless system. The spatially sparse massive MIMO channel is modelled using response matrices for basis arrays matching to quantized directional cosines at the transmitting and receiving antenna arrays, and then a sparse Bayesian learning (SBL) channel estimation technique based on expectation maximisation (EM) is developed. Genie (Ideal) channel estimation is also performed in which we presume that actual angle of departures (AoD) and angle of arrivals (AoA) are known to us in multimedia. Finally, the Multimedia simulation results reveal that suggested SBL-based channel estimation approaches outperform the popular OMP-based methodology and conventional approaches like least-squares channel estimation.
Influence of Peach Seedling Rootstocks on Defoliation and Cold Hardiness of Peach Cultivars1
Authors: Layne R. E. C. , Jackson H. O. , Stroud F. D.
Published: August 2022

Bearing trees of ‘Loring’, ‘Redhaven’ and ‘Babygold 5’ peach trees (Prunus persica (L.) Batsch) on Siberian C seedlings defoliated earlier than those on the other seedling rootstocks. Early cold acclimation of scions in the fall and scion cold hardiness in mid-winter were enhanced more by Siberian C seedlings than by those of the other seedling rootstocks. Bud survival and fruit set of ‘Redhaven’ and ‘Bablygold 5’ scions were greater on Siberian C seedlings than on any of the other seedling rootstocks following an outdoor cold stress at -23.4°C in January. The cold hardiness of phloem, cambium, and xylem stem tissues were closely correlated with each other in the fall, but were not correlated with cold hardiness of flower buds on the same shoots. Seedlings of Siberian C appeared to enhance early scion dormancy and they increased scion bud hardiness by as much as 4.7° in the fall, and 1.3° in mid-February, compared with those of other rootstocks tested.
Nitrogen Fertilizer Requirements of Pickling Cucumbers Grown for Once-over Harvest I. Effect on Yield and Fresh Quality1
Authors: Cantliffe Daniel J.
Published: August 2022

Different preplant and sidedress N fertilizer rates from NH4NO3 or urea were applied to pickling cucumbers (Cucumis sativus L.) grown for once-over harvest to determine the effect of N rate, source and time of application on cucumber yield, sex expression, and fruit quality. Nitrogen preplant rates of 67 or 134 kg/ha resulted in greater yields ($/ha and MT/ha) than no N preplant fertilizer. Preplant rates of 201 or 268 kg N/ha gave lower yields. The preplant source of N, NH4NO3 or urea had no effect on yield. Sidedress N as NH4NO3 or urea generally did not influence yields ($ and MT) when preplant N was used at rates of 67 or 134 kg/ha. The addition of preplant N fertilizer up to 134 kg/ha resulted in a slightly greater number of pistillate flowers per plant. The percentages of off-shape fruit were higher for the highest rate (268 kg/ha) of preplant N. Fruit quality evaluation (shape and color) and length:diameter ratios were generally not influenced by preplant N fertilizer.
Nitrogen Fertilizer Requirements of Pickling Cucumbers Grown for Once-over Harvest II. Effect on Plant Tissue Mineral Nutrient Concentrations1
Authors: Cantliffe Daniel J.
Published: August 2022

Pickling cucumbers (Cucumis sativus L.) were grown at high plant population (250,000 plants/ha) for once-over harvest. Nitrogen was applied preplant, 0 to 268 kg/ha, and sidedress, 0 to 112 kg/ha, from 2 N sources, NH4NO3 and urea. The effects of N fertilization practices on mineral nutrient composition of the tissue was studied. The concentration of NO3-N in leaf blade and petiole tissue rapidly decreased during the last 2 to 3 weeks before harvest (fruit sizing period). Preplant and sidedress N fertilizer applications led to increased tissue concentration of NO3-N and total N. Petiole tissue concentration less than 0.8% NO3-N or greater than 1.5% at harvest usually reflected reduced yields. Optimum yields generally occurred when blades contained 4 to 5% total N. The source of N fertilizer used had little influence on tissue concentration of NO3-N and total N. Nitrogen fertilization practices had a direct influence on the mineral nutrient composition of the leaf tissue at harvest. Tissue concentration of K, Ca, Mg, Fe and Mn were higher in tissue that received preplant fertilizer N rates from 67 to 201 kg/ha compared to plants that received no preplant N, while the Na concn was reduced. Sidedressing N fertilizer had little influence on cation and anion accumulation in the tissue.
Accumulation of Sugars and Plasmalemma Alterations: Factors Related to the Lack of Cold Acclimation in Young Roots1
Authors: Wiest Steven C. , Steponkus Peter L.
Published: August 2022

The possibility that low cellular concentration of sucrose was limiting the expression of hardiness in young roots of Pyracantha coccinea Roem. ‘Lalandii’ Dipp. was investigated. While the sucrose content of young roots increased four-fold following exposure to 4°C, the highest concentration was not higher than that found in non-acclimated mature roots. Attempts to increase hardiness by incubating young roots on sucrose solutions were unsuccessful. However, intracellular sucrose concentrations were not significantly increased by this treatment. Cytochrome oxidase incorporated into a membrane fraction containing plasmalemma vesicles isolated from Pyracantha young roots or from tissue capable of acclimation (Hedera helix L. ‘Thorndale’ callus cultures) was used as a probe for architectural alterations of this membrane following exposure to 4° and 5°. The apparent first order rate constant of the cytochrome oxidase reaction was used to indicate membrane fluidity. Above the Arrhenius discontinuity, membrane fluidity in both species was greatest when plants were grown at 4° or 5°. However, below the Arrhenius discontinuity fluidity remained greater in ivy callus grown at 5°, but not in Pyracantha young roots exposed to 4°. Altered properties of the membrane surface, inferred from the second order rate constant, were observed only in plasmalemma of young roots. Several possibilities to account for the lack of young root hardiness are presented.
Correlations of Chilling Requirements for Germination, Blooming and Leafing within and among Seedling Populations of Almond1
Authors: Kester D. E. , Raddi Paolo , Asay R.
Published: August 2022

Relationships among blooming and leafing dates of parents, offspring, and the chilling requirements of the intervening seed were determined among a group of families of almond (Prunus amygdalus Batsch). Parentoffspring heritabilities for blooming and leafing dates were high. Leafing and blooming dates of individuals and families, although significantly correlated, were more or less independent traits. Seed chilling was a function of both seed and pollen parents and was correlated with mean bloom and leafing of parents. The correlation coefficient between chilling of a seed and the blooming date of the corresponding offspring plant was significant and large when calculated for families and significant, but low, when calculated for individuals. The seed-leafing correlation was significant when the early and late leafing progeny were considered separately.
Mineral Element Changes in Pistachio Leaves1
Authors: Uriu K. , Crane Julian C.
Published: August 2022

Concentrations of several mineral elements in leaflets of Pistacia vera L. cv. Kerman, did not differ significantly with leaflet position. Thus, leaflets may be used instead of whole leaves in leaf sampling. Analyses of leaflets indicated that N, P, and Zn concn were relatively high initially. They then dropped rapidly during leaf expansion, reaching a steady state in early summer. Manganese increased from an initially low level and then remained fairly constant. Potassium, Mg, Cl, and B behaved similarly to Mn, but reached constant levels later in the season. Leaves from bearing branches were lower in N and P, but higher in K than leaves from nonbearing branches. It is recommended, in determining mineral element status, that leaves from nonbearing branches be sampled during the month prior to harvest, as most elements are then at a steady state.
Glucose Metabolism in Petals of Senescing Roses1
Authors: Buxton Jack W. , Stoltz L. P.
Published: August 2022

The pentose phosphate shunt (PPS) was shown to be active in roses (Rosa hybrida L.). The C6/C1 ratio indicated that possibly as much as 50% of the glucose oxidized in the rose flower is through the PPS. However, the activity of the PPS in relation to the Embden-Meyerhof-Parnas pathyway-tricarboxylic acid cycle (EMP-TCA) pathway did not change significantly throughout the cut life of the rose. There was a drop in the respiratory rate of petals throughout the cut flower life. The inner petals exhibited a consistantly higher respiratory rate than did outer petals regardless of whether the flower was kept in water or preservative.
Fruit Growth and Development, Ripening, and the Role of Ethylene in the ‘Honey Dew’ Muskmelon1
Authors: Pratt Harlan K. , Goeschl John D. , Martin Franklin W.
Published: August 2022

The muskmelon cultivar Honey Dew (Cucumis melo L.) has unique horticultural and physiological characteristics, most notably an unusually long period between attainment of acceptable horticultural maturity and self-ripening in the field. Patterns of flowering, fruit set, fruit growth, solids accumulation, softening, ethylene production, respiration, and variation among individual fruits were studied during several seasons. Internal ethylene concentration may be estimated by the following formula: ppm internal = 3.7 ± 1.2 × rate of production in µl/kg-hr. The act of harvesting had no effect on ethylene production or internal concentration. Full ripening required an internal ethylene concentration of about 3 ppm. Horticultural maturity was attained at 35 to 37 days after anthesis, but self-ripening required about 47 days. Commercial harvests include fruits in this range of ages, so treatment with ethylene is required for uniform ripening and consumer satisfaction.
Effect of Nitrogen and Plastic Mulch on Properties of Troup Loamy Sand and on Yield of ‘Walter’ Tomatoes1
Authors: Jones T. L. , Jones U. S. , Ezell D. O.
Published: August 2022

During 1975 and the spring of 1976, N requirements were determined for irrigated ‘Walter’ tomatoes (Lycopersicon esculentum Mill.) growing on Troup loamy sand with and without polyethylene mulch. Maximum soil moisture deviation occurred in the unmulched plots in the zone of illuviation to depths of 60 to 75 cm. Moisture ranged from 3 to 15% with the maximum recorded after vines were killed by frost. Highest N concentration (15.8 ppm NO3-N) occurred in mulched plots at a depth of 15 cm; whereas the highest concentration (11.5 ppm NO3-N) in unmulched plots occurred at 45 cm. The highest yield of 29.8 MT/ha was produced with 60 kg/ha N on mulched plots. The highest yield without mulch (25.6 MT/ha) required 138 kg/ha of N.
Effects of Chronic Exposure to Gaseous Fluoride on Yield of Field-grown Bean and Tomato Plants1
Authors: MacLean D. C. , Schneider R. E. , McCune D. C.
Published: August 2022

Field plots of bean (Phaseolus vulgaris L. cv. Tendergreen) and tomato (Lycopersicon esculentum Mill. cv. Fireball 861 VR) were exposed for 43 and 99 days, respectively, to filtered ambient air or air containing hydrogen fluoride (HF) at a mean concentration of 0.6 µgF m-3. Comparisons between these treatments revealed that chronic exposure of bean to HF did not affect growth or induce foliar injury, whereas the fresh mass of marketable pods was reduced by almost 25%. There was no effect of HF exposure on growth or fruiting in tomato.
Whitefly Host Preference Associated with Selected Biochemical and Phenotypic Characteristics of Poinsettias1
Authors: Bilderback Theodore E. , Mattson Richard H.
Published: August 2022

Selected biochemical, physical, and anatomical characteristics of 9 cultivars of poinsettia (Euphorbia pulcherrima Willd) were measured and compared with adult and nymph whitefly, Trialeurodes vaporariorum (Westwood), distribution. Whiteflies were most numerous on cultivars with less chlorophyll/unit area (µg/cm2) and lighter colored bracts. Neither total sugar content nor plant growth habit was associated with whitefly distribution. Discrimination of parental groups in cultivars can be done on the basis of trichome length, type, or number. Long spike-like trichomes occur on ‘Rochford’, while ‘Eckespoint C-l’ has significantly more trichomes/unit area. Long trichomes with hooked ends, observed on ‘Annette Hegg’ may provide protection to whitefly eggs or nymphs by preventing their physical removal from underleaf surfaces. Significantly more whitefly adults and nymphs were counted on ‘Annette Hegg’ than on ‘Eckespoint C-l’ or ‘Rochford’ cultivars.
Apple Tree Growth, Net Photosynthesis, Dark Respiration, and Specific Leaf Weight as Affected by Continuous and Intermittent Shade1
Authors: Barden John A.
Published: August 2022

The effects of 80% shade from saran cloth and slats were very similar on young ‘Delicious’ apple (Malus domestica Borkh.) trees. Shoot-length increase was suppressed about 10% by shade but leaf area was unaffected. Dry weight increase for shaded trees was about 50% of that for trees in full sun. Sun leaves required about 43.1 klx for light saturation and shade leaves needed only about 19.4 klx. Net photosynthesis (Pn) of shade leaves was about 70% of that of sun leaves at light saturation. Dark respiration (Rd) rates were also higher in sun than shade-leaves. Specific leaf weight (SLW) of leaves near full expansion at the start of the experiment increased 15% under shade whereas sun-leaf SLW increased 40% during the experiment. For leaves unfolding under the differential light treatments, SLW of shade leaves averaged only 55% of sun leaves.
Effects of Naphthaleneacetic Acid on Shoot Growth of Apple Trees1
Authors: Elfving D. C. , Forshey C. G.
Published: August 2022

Naphthaleneacetic acid (NAA) treatments were applied to pruned or unpruned dormant, vigorous, upright apple branches (Malus domestica Borkh.) Bud-break was delayed by NAA, but total inhibition of bud development required the presence of actively growing shoots above the treated area. NAA reduced growth where it was applied, but because of compensating growth increases from untreated branch sections, total growth was unchanged. Applied to 1-year-old whips immediately after planting, NAA reduced the quantity of undesirable growth, increased the growth of favorably positioned shoots, and improved the crotch angles of those shoots.
The Relationship of Vegetative Maturity to Rest Development and Spring Bud-break1
Authors: Fuchigami L. H. , Hotze M. , Weiser C. J.
Published: August 2022

Rest period, the transition between summer and winter dormancy, and vegetative maturity were studied in red-osier dogwood (Cornus stolonifera Michx.) in Oregon. Maximum rest occurred in late October and early November when 180 days were required for growth resumption under favorable growing conditions. The transition between summer dormancy (correlative inhibition of lateral buds) and winter dormancy (onset of rest) occurred in early September, 21 days before maturity, 49 days before natural leaf abscission, and 56 days before maximum rest. Lateral buds of plants defoliated prior to this transition grew within 10 days while buds of plants defoliated after that date did not resume growth until spring. Vegetative maturity was achieved in late September. Plants defoliated after that time overwintered without apparent injury. Spring regrowth was normal in mature plants, but bud-break was delayed as much as 10 days as a result of defoliation the previous autumn. Vegetatively immature plants defoliated before late September died outright or sustained varying degrees of stem dieback. Natural leaf abscission occurred in late October, 49 days after plants were vegetatively mature. The extent of stem dieback was inversely related to stage of maturity, a relationship that provides a useful means of quantitatively expressing when, and to what extent, plants are mature.
Stylar-end Breakdown in ‘Tahiti’ Lime: Aggravating Effects of Field Heat and Fruit Maturity1
Authors: Davenport T. L. , Campbell C. W.
Published: August 2022

The influence of elevated temperature, fruit size, and juice content on the incidence of stylar-end breakdown, a postharvest disorder common to ‘Tahiti’ lime fruit (Citrus latifolia Tan.), was investigated. Freshly picked limes were placed in a water bath maintained at temperatures ranging from 25°C to 50° for 3 hours. The incidence of stylar-end breakdown in these fruit increased exponentially from 0% in those fruit incubated at 25° to 85% in fruit heated at 50°. A standard treatment of heating fruit for 3 hours at 42° was employed to determine the relative susceptibility of fruit varying in size and juice content. Limes less than 3.5 cm in diameter did not break down whereas the incidence of the disorder in fruit 3.5 cm to 7.0 cm in diameter, respectively, ranged from 2% to 63%. Fruit with greater than 50% juice content were more susceptible to the disorder than those with less than 50%, but no strict correlation was found. It is suggested that the incidence of stylar-end breakdown associated with heat is mediated by liquid expansion in juice vesicles giving rise to internal pressure sufficient to rupture these vesicles. Controlling postharvest temperature of limes and maintaining strict picking schedules so that fruit are not allowed to attain maximum size significantly reduces the incidence of the disorder.
Influence of Exogenous Daminozide and Gibberellic Acid on Cluster Development and Yield of the ‘Concord’ Grape1
Authors: Funt Richard C. , Tukey Loren D.
Published: August 2022

In 1968 and 1970 applications of gibberellic acid (GA) at berry shatter to mature vines of Vitis labrusca L. cv. Concord treated with succinic acid-2,2-dimethylhydrazide (daminozide, SADH) at first-bloom appeared to reduce cluster compactness by lengthening the rachis, to increase berry size, to reduce the number of shot berries, and to increase further the number of mature berries, cluster weight and yield, as compared to daminozide alone. A single application of GA at 50 ppm at berry shatter was as effective in increasing yield as daminozide at 1000 ppm at first bloom, while GA at 100 ppm was significantly more effective. When GA was combined with daminozide were counteracted. The effect of GA on vegetative development was less pronounced than on yield. Highest yield was from the sequential treatment of daminozide 1000 ppm at first bloom and GA at 100 ppm at berry shatter. In the posttreatment year, yields were significantly higher on vines previously treated with either daminozide at 1000 ppm at first bloom, GA at 100 ppm at berry shatter, or daminozide at 1000 ppm with GA at 50 ppm at first bloom.
Impact of Single Seed Descent in Selecting for Fruit Size, Earliness, and Total Yield in Tomato1
Authors: Peirce L. C.
Published: August 2022

Single seed descent (SSD) produced generally inferior fruit size, earliness and total yield among progenies as compared with pedigree (PED) selection alone and single seed descent following one cycle of pedigree selection (PDSD). The latter two systems were essentially equal in performance, but the PDSD system provided increased efficiency of time and space. Progeny tests in 1976 generally reflected the superiority that had been selected in 1975, regardless of selection system. In each system, acceptable performance was attained in at least one line. The data suggest, however, that chances of recovering high-performance lines are reduced in SSD as compared to PED or PDSD.
Carbon Dioxide, Ethylene, and Color Development in Ripening Mature Green Bell Peppers1
Authors: Saltveit Mikal E.
Published: August 2022

Mature green bell pepper fruit (Capsicum annuum L. cv. Yolo Wonder) exhibited a non-climacteric pattern of ethylene and carbon dioxide production during normal ripening and red color development at 24°C. Exposing detached mature green fruit to 500 ppm propylene in air for 48 hours, did not induce an increase in ethylene or carbon dioxide production. Wounding excised plugs of ovary wall tissue caused an increase in carbon dioxide production within one day, and an increase in ethylene production by the second day.
Effects of Cultural Practices on Acclimatization of Ficus benjamina L.1
Authors: Conover Charles A. , Poole Richard T.
Published: August 2022

Shade-grown Ficus benjamina produced under 40 and 80% shade were larger and had better grade and foliage color than sun-grown plants after 9 months growth, but trunk caliper was less. Increasing Osmocote (14.0 N – 6.2 P – 11.6 K) from 4 to 16 g per 20 cm diam pot – 3 months increased foliage color and grade but had no effect on height or trunk caliper. The best plants after 6 months indoors under 0.8 klx, 12 hours daily were those produced under 40 or 80% shade with 12 or 16 g Osmocote levels although they had higher leaf drop. Chlorophyll content (mg/cm2) of leaf tissue was highest under 40 and 80% shade. Fertilizer had no effect on this in the production area or after 3 or 6 months indoors. After 6 months indoors, chlorophyll content had decreased by nearly 50% in all treatments. Macronutrient tissue levels varied with changes in shade and fertilizer level.
Influence of the Nut's Internal Oxygen Partial Pressure on the Induction of Pigmentation in the Kernels of Pecan1
Authors: Kays S. J.
Published: August 2022

The O2 and CO2 concentration between the shuck and shell and within the nut of individual pecans (Carya illinoensis (Wang.) K. Koch cv. Stuart) was monitored over a 4 week period from predehiscence to post-dehiscence. Internal O2 levels increased after dehiscence from initial concentrations of 16-17% to near that of the external environment after 3 weeks. Internal CO2 concentration, conversely, decreased substantially after dehiscence. Treatment of nuts over the same physiological stages of development with 2.5, 5.0, 10.0, 21.0 and 100% O2 had little effect on the induction and development of the kernel's normal pigmentation. Both high and low O2 levels did, however, produce some discoloration after 21 days of treatment. Changes in the internal nut O2 partial pressure are apparently not a significant factor in the induction and development of the normal complement of pecan kernel pigments during fruit maturation.
Identification of Clones within Four Tree Fruit Species by Pollen Exine Patterns1
Authors: Fogle Harold W.
Published: August 2022

Twenty sample clones of peach (Prunus persica [L.] Batsch) and ten clones each of nectarine (P. persica var. nectarina [Ait.] Maxim.), European plum (P. domestica L.), sweet cherry (P. avium [L.] L.) and apple (Malus domestica Borkh.) were compared by scanning electron microscope (SEM) for characteristics of their pollen exine. The 4 taxa were separated into 3 groups by pollen grain size. Exine differences distinguished apple and sweet cherry pollens, which had similar size, and separated clones within each of the species. Peach and nectarine clones varied within the same ranges of pollen size and exine characteristics. Within P. persica, two patterns of ridging and the relative frequency, depth of impression, and size of pores categorized the clones individually. Plum exine patterns were distinct from those of other tree fruits, but ridging and pore characteristics of the exine separated plum clones into distinct categories. Apple cultivars, which had the narrowest ridges, were separated by the abundance and placement of pores in the exine. Sweet cherry clones also were distinguished by exine characteristics.
Branching Habit and Apical Dominance of Compact and Normal Apple Seedlings as Influenced by TIBA and GA31
Authors: Lee Jung M. , Looney N. E.
Published: August 2022

Regrowth of decapitated seedlings of apple (Malus domestica Borkh.) of a compact phenotype revealed stronger apical dominance and narrower branching angle than normal seedlings. Normal and compact seedlings were also found to differ in their phyllotaxy at lower nodes. Spraying with 2,3,5-triiodobenzoic acid (TIBA) before and/or after decapitation increased apparent apical dominance in compact seedlings; reduced shoot thickness in normal seedlings; and reduced shoot length and increased branching angle of both phenotypes. Gibberellic acid (GA3) increased shoot length and reversed the TIBA effect on branch angle in the compact seedlings. These differing growth regulator effects are thought to relate to differences in endogenous growth substance levels. Shoot tips of normal seedlings were higher in abscisic acid (ABA) but the dwarf pea bioassay indicated the presence of another acidic inhibitor present only in the compact seedlings. Normal seedlings exhibited higher levels of gibberellin-like growth promoters.
Differential Response of Tomato and Lambsquarter Seedlings to Potassium Level1
Authors: Minotti Peter L.
Published: August 2022

Sand culture experiments showed that lambsquarters (Chenopodium album L.) required greater amounts of K in the nutrient media for optimum growth than did tomato (Lycopersicon esculentum Mill.). When grown in competition, the ratio of tomato to lambsquarters decreased with increasing K level in the media. At all 5 K levels employed, lambsquarter shoots contained a greater percentage of dry matter and a greater K concentration than did tomato shoots. Optimum growth for lambsquarter required shoot K concentration twice as high as tomato. In contrast to shoots, lambsquarter roots had a higher concentration of K only at lower media K levels while tomato roots had a higher concentration of K at higher K levels. Total K accumulation per unit of root mass was greater for lambsquarters at lower K levels but equal for the species at high K levels.
Carbon Dioxide Treatments for ‘McIntosh’ Apples before CA Storage1
Authors: Bramlage W. J. , Bareford P. H. , Blanpied G. D. , Dewey D. H. , Taylor Susan , Porritt S. W. , Lougheed E. C. , Smith W. H. , McNicholas F. S.
Published: August 2022

In a collaborative study at 5 North American locations, treatment with 12% CO2 and 3 to 5% O2 for 2 weeks at 0° to 3°C at the beginning of controlled atmosphere (CA) storage significantly delayed softening of ‘McIntosh’ apples (Malus domestica Borkh.). Softening was retarded further when treatment time and CO2 concentration were increased, and when fruit was harvested less mature. The effect was diminished by treatment at 0°, and was nullified by delayed treatment and slow cooling during treatment. Softening response to CO2 was not influenced by O2 concentration or storage humidification during treatment. CO2 treatment reduced the rates of CO2 and ethylene evolution from the fruit, even after 4 to 5 months of subsequent CA storage, but affected neither soluble solids nor titratable acidity of fruit after storage. When taste panelists could distinguish CO2-treated from nontreated CA apples, they preferred the treated fruit.

These beneficial results were usually accompanied by external CO2 injury, and occasionally by internal CO2 injury; 30 to 50% of the fruit were injured in some tests. Treatment in a non-humidified room reduced CO2 injury without also reducing treatment benefits. We conclude that for ‘McIntosh’, the potential for injury outweighs the benefits obtained from CO2 pre-treatment in CA storage.
Uptake of Calcium by Apples from Postharvest Dips in Calcium Chloride Solutions1
Authors: Betts Heather A. , Bramlage W. J.
Published: August 2022

Uptake of Ca by apples (Malus domestica Borkh.) from a postharvest dip in CaCl2 solutions increased as CaCl2 concentration in the dip solution increased up to 3-4%; a 4% solution increased flesh Ca level by 60 to 100 ppm after 3 months of storage. Uptake occurred primarily during storage, apparently as Ca from residues left by the dipping treatment diffused through openings in the fruit surface. Absorbed Ca remained largely near the fruit surface, although some deeper penetration occurred. Uptake from a 2% CaCl2 solution was not influenced significantly by thickener, surfactant, fungicide, or scald inhibitor in the dip solution, and was not consistently influenced by storage at relative humidities of from 90% to greater than 95%. When relative humidity had an effect, uptake was reduced at concentrations greater than 95%. A 4% CaCl2 dip treatment reduced softening and development of senescent breakdown in ‘McIntosh’, but did not significantly modify quality of ‘Cortland’ or ‘Baldwin’ apples.
Induction of Cold Hardiness in Apple Tree Shoots with Ethephon, NAA, and Growth Retardants1
Authors: Raese J. Thomas
Published: August 2022

Growth regulators were applied in early autumn to evaluate their effects on induction of cold hardiness in 2-year-old apple shoots, as determined by the conductivity test. Mid-October applications of 500 ppm (2-chloroethyl)phosphonic acid (ethephon), followed 11 days later by 100 ppm of naphthaleneacetic acid (NAA), increased cold hardiness up to 5°C by early November in 1974 and to a lesser extent in 1976. Two annual sprays of succinic acid-2,2-dimethylhydrazide (daminozide, SADH) in June increased cold hardiness slightly (2 to 3°C) in late fall of 1974, 1975, and 1976. However, in 1974 treated trees were no hardier than the controls later in the winter and fruit set on ethephon-treated trees was severely reduced. In most cases, the combined content of fructose, glucose, sucrose, and sorbitol in the 2-year-old wood was slightly higher in treatments that induced cold hardiness in November or December, 1974 than in the controls. Techniques are described for screening growth regulators for induction of cold hardiness and estimating relative cold protection.
Quality and Value of Walnut Kernels as Affected by Ethephon, Delay in Harvest, or Prolonged Drying1
Authors: Martin George C. , Sibbett G. Steven , Draper T. M.
Published: August 2022

Walnuts (Juglans regia L.) with and without (2-chloroethyl)phosphonic acid (ethephon) treatment were harvested at the earliest practical time and 3, 7, and 10 days later. With both treatments a delay in harvest resulted in kernels of lower quality and subsequent value. Furthermore, lower quality was found in earlier maturing than in later maturing walnuts when harvested from the same tree on the same day. In all comparisons kernels from ethephon-treated nuts were of higher value than controls. Walnuts left in the drier beyond the time necessary to remove excess moisture lost negligible quality and value.
Effect of Soil Compaction on Nitrogen and Water Use Efficiency, Root Growth, Yield, and Fruit Shape of Pickling Cucumbers1
Authors: Smittle D. A. , Williamson R. E.
Published: August 2022

Root growth of cucumber (Cucumis sativus L.) was not greatly restricted by soil strength less than 500 kPa (5 bars). Root growth was inhibited 80% at a soil strength of 850 kPa. Mechanical compaction produced by a tractor wheel resulted in a 50% reduction of tissue NO3 at comparable soil NO3 levels, a 25 to 35% yield reduction, and a decrease in fruit length/diameter ratio. The effects of soil compaction could be partially alleviated by increasing the rate of nitrogen fertilization; however, a 3-fold increase in N fertilization did not completely counteract the effect of compaction on cucumber yield. A system for cucumber seedbed preparation which reduces soil compaction is presented.
Genotype Variation in Pecan Kernel Color and Color Stability during Storage1
Authors: Kays S. J. , Wilson D. M.
Published: August 2022

Substantial quantitative differences in kernel pigmentation of pecan (Carya illinoensis (Wang) K. Koch) were measured in 8 cultivars and 1 selection. These pecans exhibit a wide range in color stability with storage and reversibility of detrimental color changes using surface pH alteration. Major differences were found between genotypes in the positive benefit from storage in the unshelled versus the shelled state.
Winter Rainfall Reduces Rest Period of Apple and Pear1
Authors: Westwood M. N. , Bjornstad H. O.
Published: August 2022

Repeated winter rain or water soaking in the laboratory reduced the time required for breaking winter rest of ‘Bartlett’ pear (Pyrus communis L.) and ‘Starkrimson’ apple (Malus domestica Borkh.). Possibly a water soluble inhibitor is leached from the buds.
Mechanism of Supercooling in Overwintering Peach Flower Buds1
Authors: Quamme H. A.
Published: August 2022

A study to determine the freezing pattern in overwintering flower buds of peach (Prunus persica (L) Batsch) revealed that masses of ice formed in the flower bud scales and flower bud axis, but not the flower primordium. Water appeared to be withdrawn from the bud axis to freeze in preferred sites in the scales, but not from the flower primordium. The flower primordium appeared to survive to below −20°C by supercooling. Below −10°C the supercooled flower primordium could be induced to freeze by inoculating it with ice or excising it from the flower bud at the base. It is proposed that 2 barriers operate below −10°C to prevent external nucleation of the supercooled tissue, 1) the cuticle or epidermis which prevents nucleation by ice on the surface of the flower primordium, and 2) a dry region at the base which prevents an ice boundary from spreading into the flower primordium from the interior of the bud axis. The dry region is formed by water withdrawal into the scales during the initial stages of freezing. Below some critical temperature the ice boundary spreads through the dry region or the supercooled tissue nucleates spontaneously. The sudden explosive growth of ice kills the flower primordium, probably by intracellular freezing.
Overtree Misting for Bloom Delay in ‘Golden Delicious’ Apple1
Authors: Stang Elden J. , Ferree David C. , Hall Franklin R. , Spotts Robert A.
Published: August 2022

Spring overtree misting using greenhouse mist nozzles was tested for effects on bloom delay, incidence of disease, European red mite populations, fruit size, maturity, fruit russeting and tree survival of ‘Golden Delicious’ apple (Malus domestica Borkh.) on Mailing 9 rootstock. Bloom delay of 9 and 8 days was observed in misted trees in 1975 and 1976, respectively, Apple scab was controlled with standard fungicide spray programs, but fireblight was severe in 1975 on misted trees. European red mite (Panonychus ulmi Koch.) egg hatch was delayed on misted trees but post treatment populations were not affected. Phytotoxicity occurred on calyx and foliar tissue in misted trees in 1975. Fruit set and yield were reduced in misted trees in both years. Fruit size in misted treatments in 1975 was reduced through late July, but was comparable at harvest. In 1976, misted fruit size was reduced. Fruit color, soluble solids and firmness tests indicated maturity was delayed by mist. Fruit russeting in spring misted treatments was reduced. Substantial tree losses occurred in misted treatments in 1975.
Population Studies of Pratylenchus penetrans and its Effects on Peach Seedling Rootstocks1
Authors: Johnson P. W. , Dirks V. A. , Layne R. E. C.
Published: August 2022

Field samplings in 3 peach orchards with 4 seedling rootstocks showed that Siberian C seedlings had significantly higher levels of Pratylenchus penetrans [(Cobb) Filip, and Stek.] populations in both root tissues and surrounding soil than 3 other seedling rootstocks tested. Little difference in nematode populations could be shown between seedlings of Veteran, Harrow Blood and Rutgers Red Leaf. Greenhouse studies of infected and nematode-free seedlings of these rootstocks confirmed field results. Significant reduction in growth occurred in all the rootstocks tested, with Siberian C seedlings being the most severely affected. Nematode control and plant breeding implications are discussed.
Mycorrhizal Influence on the Nutrition of Strawberries1
Authors: Hughes Megan , Martin Lloyd W. , Breen Patrick J.
Published: August 2022

Strawberries (Fragaria × ananassa Duch. cv. Hood) were grown at three levels of soil P and inoculated with either Glomus fasciculatus (Thaxter sensu Gerd.) Gerd. & Trappe or Gigaspora calospora (Nicol. & Gerd.) Gerd. & Trappe mycorrhizal fungus. P and N concentration in the aerial part of inoculated plants were higher than in controls; highest concentrations were found in plants inoculated with Glomus fasciculatus. Inoculation with this fungus also resulted in the greatest length of mycorrhizal roots and the highest percentage of total root length infected.
The Effects of Evaporative Cooling for Bloom Delay on ‘Bartlett’ and ‘Bosc’ Pear Fruit Maturity and Quality1
Authors: Collins M. D. , Lombard P. B. , Wolfe J. W.
Published: August 2022

Mature orchard misting and sprinkling and young hedgerow misting for bloom delay of pear (Pyrus communis L.) reduced fruit sizes of ‘Bartlett’ 6% and of ‘Bosc’ 12%. Harvest maturity, indicated by fruit pressure testing, was delayed 0 to 6 days for ‘Bartlett’ and 2 to 7 days for ‘Bosc’. The effect of bloom delay on fruit size and maturity was greater on ‘Bosc’ than ‘Bartlett’. Bloom delay had a greater effect on fruit sizing at harvest (3.5 days for every 6 days of bloom delay) than on harvest maturity (1 day for every 6 days delay). Soluble solids, not affected in pears from the mature plots, were slightly lower in the misted hedgerow. Titratable acids were not influenced by bloom delay.
Lime and Charcoal Amendments Reduce Fluoride Absorption by Plants Cultured in a Perlite-peat Medium1
Authors: Sheldrake Raymond , Doss George E. , St. John Leigh E. , Lisk Donald J.
Published: August 2022

Lime or activated charcoal effectively reduced fluoride absorption and increased plant dry weight in lettuce (Lactuca sativa L.), perennial ryegrass (Lolium perenne L.), and spinach (Spinacia oleracea L.) grown in a fertilized perlite-peat moss medium. Lime in combination with charcoal surpassed that of charcoal alone in reducing fluoride absorption and increasing yields. While the addition of lime or charcoal raised the pH of the growth medium only the lime greatly reduced water-soluble fluoride.
Heterosis and Phenotypic Stability of F1 Hybrids in Cucumber Under Controlled Environment1
Authors: Ghaderi Ardeshir , Lower R. L.
Published: August 2022

Three F1 hybrids of cucumber (Cucumis sativus L.) and their inbred parents were grown at 2 day/night regimes (30°/20°C and 27°/14°) under controlled environment. Hybrids were superior in fresh weight under both temperatures at each of 2 stages of growth and had higher phenotypic stability than their parents.
Conversion of Central Leader Apple Trees for Improved Mechanical Harvest1
Authors: Lakso A. N. , Millier W. F. , Pellerin R. A. , Carpenter S. G.
Published: August 2022

Eight-year-old, semi-standard ‘McIntosh’ apple trees (Malus domestica Borkh.) were converted from central leader trees to open center trees by removal of the central leader. The productivity of the converted trees was not reduced in the first year due to better fruit set and size, and flowering and yield of the open center and central leader trees were similar in the second year. Open center trees resulted in less damage to the fruit during mechanical harvest, primarily due to reduction in fruit zone height.
Ethylene in Fruits of Blackberry and Rabbiteye Blueberry
Authors: Lipe John A.
Published: August 2022

In the paper entitled “Ethylene in Fruits of Blackberry and Rabbiteye Blueberry” by John A. Lipe (J. Amer. Soc. Hort. Sci. 103(1):76-77. 1978) ethylene concentrations in the text are erronously expressed as mg/liter. These units should be ppm of μl/liter
Pesticide Effects on the Plant Cuticle: III. EPTC Effects on the Qualitative Composition of Brassica oleracea L. Leaf Cuticle1
Authors: Flore J. A. , Bukovac M. J.
Published: August 2022

S-Ethyl dipropylthiocarbamate (EPTC, 2.24 kg/ha) altered wax composition on developing leaves of cabbage [Brassica oleracea L. (Capitata group) cv. Market Prize], but did not affect cutin composition. The alkane, ketone and secondary alcohol content of the epicuticular wax was reduced and ester content increased. C29 constituents (alkane, ketone, aldehyde and sec-alcohol) accounted for 72.5% (34.1 μg/cm2) and 40.2% (7.2 μg/cm2) of the epicuticular wax on control and EPTC-treated leaves respectively. Homlog composition within a chemical group was not changed. Chemical composition was similar for abaxial and adaxial leaf surfaces, and the EPTC-induced change in chemical composition was similar for both surfaces. In contrast with epicuticular wax, cuticular wax contained higher percentages of fatty acids and primary alcohols, and lower percentages of alkanes, and ketones. All constituents except the unidentified polar materials and fatty acids were lower in cuticular wax extracted from EPTC-treated than non-treated plants. The main component of the cutin fraction from both control and EPTC-treated plants was identified as dihydroxyhexadecanoic acid. Cutin acids were not quantitatively changed by the EPTC treatment.
Effects of Sodium Azide Soil Treatments on Quality of Vegetable Root Crops1
Authors: Constantin Roysell J. , Sitterly Wayne R. , Ogle W. L.
Published: August 2022

Sodium azide (NaN3) applied at 134.4 kg/ha as a soil fumigant did not drastically alter the quality of vegetable root crops grown on treated soil. Azide soil treatment had no influence on quality of beets (Beta vulgaris L.) or potatoes (Solanum tuberosum L.). Differences were noted in quality of turnips (Brassica rapa L.) during 1976; however, no differences were found during the 1977 growing season at 2 locations. Azide soil treatments resulted in differences in quality of carrots (Daucus carota L.). Some differences that occurred were beneficial such as increased size and carotenoid content of carrots.
Inheritance and Selection of Nonpreference Resistance to the Cowpea Curculio in the Southernpea (Vigna unguiculata (L.) Walp.)1,2
Authors: Fery R. L. , Cuthbert F. P.
Published: August 2022

The southernpea breeding line, CR 18-13-1, a source of nonpreference resistance to the cowpea curculio, was crossed with the susceptible breeding line, Fla. 589.06. The F1, F2, and backcross progenies of this cross and the parental lines were grown in outdoor screen-cage and field tests over a 3-year period. Large error variances were noted in all tests because of apparent plant-to-plant variation in number of curculios. Resistance was inherited in a partially dominant manner and broad-sense heritability estimates ranged from 0.0 to 19.1%. Selection in the seedling stage for low amounts of adult curculio feeding damage increased the frequency of resistant plants.