bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agrobacterium-mediated Transformation of Peach Cells Derived from Mature Plants that were Propagated in Vitro
Authors: Hammerschlag A. , Owens L. D. , Smigocki A. C. 
Published: August 2022

Abstract
Stem explants of in vitro-propagated peach (Prunus persica L. Batsch.) cultivars Compact Redhaven, Jerseyqueen, Rio Oso Gem, and Suncrest and peach rootstock Nemaguard were infected with several strains of Agrobacterium tumefaciens. Tumor tissue was produced on all cultivars infected with strain tms328::Tn5, which carries a mutated octopine Ti plasmid pTiA6. The tumor tissues were cytokinin-independent and all tissues, except those on ‘Rio Oso Gem’, produced octopine. A DNA probe specific for the T-DNA region of the Ti plasmid hybridized to the DNA extracted from these tumors. No tumor tissue was produced in response to inoculation of the stem explants with the Ti-plasmidless strain A136 or with uninoculated controls. These results demonstrate the transformation of peach cells derived from mature plants and the potential for using A. tumefaciens to transfer economically important genes to peach.
Histology of Zygotic and Somatic Embryogenesis in Borage
Authors: Quinn James , Simon James E. , Janick Jules 
Published: August 2022

Abstract
Embryo sac formation in borage (Borago officinalis L.) was of monosporic, Polygonum type. Zygotic embryogenesis resembled the Piperad type (Myosotis Variation) without a suspensor after the four-cell stage with free nuclear endosperm. Cotyledons were initiated 4 days after pollination (DAP) and grew rapidly until 12 to 14 DAP, with seed maturity at 18 DAP. There were two patterns of in vitro somatic embryo development from embryogenic callus: 1) from single cells, which proceeded through typical zygotic embryo stages; or 2) from groups of cells that developed as a meristem. The advanced stages of somatic embryogenesis were characterized by abnormal cotyledon and hypocotyl morphology and incomplete apical development.
The Possible Use of the Crop Water Stress Index as an Indicator of Evapotranspiration Deficits and Yield Reductions in Sweet Corn
Authors: Braunworth William S. , Mack Harry J. 
Published: August 2022

Abstract
The crop water stress index (CWSI) may be useful for optimal irrigation timing. This preliminary study evaluates the relationships between the CWSI and evapotranspiration (ET) and yield. The CWSI was also characterized on an hourly basis. Once-daily CWSI measurements after full ground cover was established and hourly CWSI measurements on 4 days were made in sweet corn (Zea mays L. ‘Jubilee’) irrigation experiments in 1984 and 1985. The gradient of water applied included five irrigation levels established from 0% to 100%, with the 100% level intended to refill the root zone to field capacity, after 50% depletion of available water, at each irrigation. CWSI values, obtained hourly throughout the day, were highest between 1000 and 1700 hr. CWSI values tended to be higher in the less-irrigated plots (40% and less) than in those that received greater amounts of water (57% to 100% treatment levels). Seasonal average CWSI values (midday measurements) were closely related to the seasonal ET deficit (r2 ranged from 0.45 to 0.96), but there was not the expected 1:1 relationship of CWSI and ET deficit. The yield deficit of good, husked ears was also closely related to CWSI (r2 ranged from 0.82 to 0.93), but differences in these relationships between years and experiments indicate that CWSI measurements must be improved.
High-temperature Stress and Mitochondrial Activity of Harvested Mature-green Tomatoes
Authors: Inaba Makoto , Chachin Kazuo 
Published: August 2022

Abstract
Mature-green tomatoes (Lycopersicon esculentum M. cv. Sakata TVR) were stored at 5, 10, 15, 20, 25, 30, 35, or 40C. During storage, the respiration rate and C2H4 production were suppressed at 5, 10, and 35C. Tomato ripening and ethylene production were suppressed and injury was obvious at 40C. Mitochondrial oxidation of malate, succinate, α-ketoglutarate, and citrate were significantly suppressed at 30 and 35C. The respiratory control ratios and ADP:O ratios of 35C were consistently lower than those at 25C. Tomato mitochondria developed the cyanide-insensitive pathway of respiration with increased storage temperature, especially at 30 and 35C, and with extended storage time. The NAD+ -dependent malic enzyme increased at 35C, but malate dehydrogenase activity did not increase with ripening at 35C.
Light-mediated Inhibition of in Vitro Late Embryogeny of Ilex
Authors: Ferreira Alfredo G. , Hu Ching-yeh 
Published: August 2022

Abstract
An inhibitory effect of light on in vitro late embyogeny of I. aquifolium and I. opaca cv. Farage was observed. A negative log-linear correlation between the final embryo size and hours of continuous light during preincubation, at an intensity of 64 W·m−2, was established with I. aquifolium. It took ≈ 15 hr of pre-incubation light to result in 50% growth inhibition. Negative log-linear correlations between the final embryo lengths and light intensities were also observed for I. aquifolium and I. opaca. The rudimentary embryos of I. opaca were more sensitive to light inhibition than those of I. aquifolium. During incubation for 11 and 14 days with a 16-hr photoperiod, light intensities for 50% growth inhibition were ≈ 5 and 11 W·m−2 for I. opaca and I. aquifolium, respectively. Since growth inhibition by light could not be reversed by the presence of GA3 concentrations up to 1000 μm, some factor(s) other than the accumulation of abscisic acid or related compounds is probably responsible for such a phenomenon.
Free and Bound Residues of 2,4-D in ‘Marsh’ Grapefruit and ‘Washington’ Navel Orange Fruit
Authors: Erner Yair , Coggins Charles W. 
Published: August 2022

Abstract
Good preharvest fruit drop control toward the end of navel orange [Citrus sinensis (L.) Osbeck] and grapefruit (Citrus paradisi Macf.) harvest seasons in California may require higher than maximum label rates of 2,4-D. Therefore, residues from preharvest aqueous applications of 2,4-D made at 1.5 to 2 times higher than current label rates for preharvest fruit drop control were determined. In navel orange, the residue range found for free plus bound 2,4-D was 0.03 to 0.52 ppm in the flavedo and 0.05 to 0.14 ppm in the albedo. The free plus bound 2,4-D residue range found in grapefruit rind tissue was 0.11 to 0.22 ppm. Only trace amounts were found in pulp tissue of either cultivar. When pH was carefully controlled during each step of the fractionation procedure, recoveries of 2,4-D in excess of 83% were obtained. Residues found were considerably lower than established tolerances of 5 ppm in the United States and 2 ppm in some other countries. Thus, residues would permit higher application rates if needed and if label rates were increased. Chemical name used: 2,4-dichlorophenoxy acetic acid (2,4-D).
Organogenesis from Immature Pecan Embryonic Axes in Vitro
Authors: Yates I.E. , Wood B.W. 
Published: August 2022

Abstract
Immature embryos were excised during kernel development from fruits of the pecan [Carya illinoensis (Wangenh.) C. Koch] cultivars Desirable and Stuart. The cotyledons were removed and the main embryo axes were used as explants. Explants were cultured in vitro on media containing various levels of cytokinins and auxins. Morphogenesis in ‘Stuart’ preceded that of ‘Desirable’ by 1 to 2 weeks. In both cultivars, the percentage of embryo axes forming shoots only or both shoots and roots increased until ≈4 to 6 weeks before nut maturity, as judged by shuck dehiscence. After this time, developmental responses declined. Production of normal plants was highest on a medium containing IBA, BA, and kinetin at 0.5, 4.4, and 9.3 μM, respectively. Shoots only were obtained on a medium containing cytokinin without auxin and roots only on a medium containing auxin with no cytokinin. Axillary shoots elongated from embryo axes of both cultivars. This response was greatest on a medium containing cytokinin as the only hormone for ‘Desirable’, but with both auxin and cytokinin for ‘Stuart’. Chemical names: indole-3-butyric acid (IBA); N-(phenylmethyl)-1H purin-6-amine (BA); N-(2-furanylmethyl)-1H-purin-6-amine (kinetin).
Solution Depth Affects Root Morphology and Growth of Cucumber Plants Grown in Circulating Nutrient Solution
Authors: Chung Gap C. , Rowe Richard N. , Field Roger J. 
Published: August 2022

Abstract
Defruited cucumber (Cucumis sativus L.) plants were grown hydroponically for 28 days in containers with 4.5 liters of capacity, in which constant solution depths of 1, 5, 50, and 170 mm were maintained. The plants grown in the 1- and 5-mm-deep solutions grew more slowly than those in the deeper solutions. Both root and shoot growth were reduced at the shallow depths, but shoot growth was affected more than root growth. Thus, the shoot : root ratios were considerably smaller in the shallower than in the deeper solutions. The root systems in the shallower solutions, initially, were relatively more branched than in the deeper solutions. The shallow solutions caused the plants to allocate a higher proportion of their photosynthetic resources to the root at the expense of leaf growth. In the shallow solutions, a progressively higher proportion of this root growth became exposed above the solution, and, therefore, could not contribute to the absorption of water and nutrients. Control of solution depth may be a useful tool for controlling the vigor of the shoots of cucumber and the data presented may explain why growth problems have been experienced with this crop, particularly where a very thin film of nutrient is used, as in nutrient film technique.
Decay Control and Quality Maintenance after Moist Air Heat Treatment of Individually Plastic-wrapped Nectarines
Authors: Anthony Bryan R. , Phillips D.J. , Badr S. , Aharoni Yair 
Published: August 2022

Abstract
Moist air heat treatment at 52C for 15 min prevented decay in individually plastic-wrapped or naked nectarine [Prunus persica (L.) Batsch var. nectarina (Ait.) Maxim.] fruit puncture-inoculated with Monilinia fructicola (Wint.) Honey. Heat treatment for 5 or 10 min slowed decay development, but did not prevent it. In treatments where decay occurred, the wrap increased decay. Heat treatment tests at 52C for 15, 30, 45 min slowed softening and ethylene production of fruit. Wrapping alone reduced ethylene production 75% and respiration 12%, but did not significantly influence softening. The wrap reduced or eliminated undesirable skin browning associated with heat treatments.
Hormonal Basis for Low Light Intensity-induced Flower Bud Abscission of Pepper
Authors: Wien H.C. , Turner A.D. , Yang S.F. 
Published: August 2022

Abstract
A series of field and greenhouse experiments was conducted with three cultivars of bell pepper (Capsicum annuum L.) to determine the hormonal basis for flower bud and flower abscission as induced by low light intensity (LLI). Imposition of 80% shade for 6 days increased abscission of reproductive structures by 38% and resulted in an increase in bud ethylene production. Concomitantly, bud reducing sugars and sucrose decreased and these were negatively correlated with ethylene levels and those of its precursor, ACC. Infusion of ACC into the pedicel resulted in flower bud abscission within 48 hr. The results indicate that ethylene is the primary causal agent of pepper flower bud abscission. Production of auxin by the bud plays a role in prevention of abscission. The abscission of disbudded pedicels was prevented by infusion of NAA. Although the three cultivars had similar responses to ACC, they differed in the amount of abscission under stress, bud sugar levels, and the time of onset of ACC and ethylene production. Chemical names used: 1-aminocyclopropane-1-carboxylic acid (ACC); α-napthaleneacetic acid (NAA); (2-chloro-ethyl)phosphonic acid (ethephon).
Net Photosynthesis and Stomatal Conductance of Peach Seedlings and Cuttings in Response to Changes in Soil Water Potential
Authors: Harrison R.D. , Daniell J.W. , Cheshire J.M. 
Published: August 2022

Abstract
Greenhouse-grown peach [Prunus persica (L.) Batsch] seedlings and cuttings were drought-stressed by reducing soil water potential (ψsoil) from field capacity (FC) to permanent wilting point, (PWP). Mean ψsoil and leaf water potential (ψleaf) were correlated with measurements of stomatal conductance (gs), net photosynthetic (Pn) rate, and vapor pressure deficit (VPD). Decreasing Pn and gs trends were noted as ψsoil decreased. Photosynthetic rate and gs were significantly reduced at ψleaf more negative than −1.5 MPa. Values of Pn and gs were more highly correlated to ψleaf than ψsoil. A midday depression in Pn rates began 2 hr earlier and peak rates were at least 50% lower when ψsoil was more negative than −0.05 MPa. The correlation coefficient (r) between ψleaf and ψsoil and between gs and Pn rate at different ψsoil was above 0.70. The r values decreased as soil and plant water potential became more negative. Stomatal conductance peaked at optimal ψsoil (FC) 2 hr following sunrise. Photosynthetic rate peaked at a ψsoil around −0.05 MPa 4 hr after sunrise.
The Effect of Calcium on Respiration of Apples1
Authors: Faust Miklos , Shear C. B. 
Published: August 2022

Abstract
Respiration of apples was inversely related to Ca content of flesh. Respiration increased markedly if Ca concn was below 110 ppm. High N levels also increased respiration. High Ca successfully counteracted the N effect and kept the respiration at a low level. When N was supplied as ammonium, respiration was higher than when a similar quantity of N was supplied as nitrate. Calcium counteracted the increased respiration induced by ammonium-N. Low Ca fruit lost 30-70% of its capacity to synthetize proteins and nucleic acids as measured by the incorporation of labelled valine and uracil. Low-Ca fruit was also high in ethanol insoluble solids, the major portion of which was probably cellulose. The effect of Ca on respiration can explain the negative relation between certain disorders (internal breakdown and watercore) characterized by overmaturity and Ca content of fruit.
Potassium in Onion Nectar and its Probable Effect on Attractiveness of Onion Flowers to Honey Bees1
Authors: Waller G. D. , Carpenter E. W. , Ziehl O. A. 
Published: August 2022

Abstract
Levels of K in nectar of onion (Allium cepa L.) varied from 3600-13,000 ppm, about 10 times higher than that of nectar from competing flora tested. An open-pollinated amphidiploid derived from the interspecific cross A. cepa X A. fistulosum L. was the only onion with nectar K level as low as that of competing flora and it was more attractive to honey bees than was the common onion, A. cepa. Addition of K salts to sugar solutions at the rate of 1500, 3000, 4500, 6000, or 7500 ppm K clearly reduced uptake of these solutions by honey bees foraging at artificial-flower feeders. Thus, it appears that the levels of K in onion nectar are high enough to reduce the attractiveness of onion flowers to honey bees. It is suggested that pollination of onion flowers might be improved if nectar K levels can be reduced, either through a program of selective breeding or by altering cultural practices. An alternative solution might be to provide pollinators that readily accept the high K level present in onion nectar. This might be accomplished by preconditioning honey bees to accept high K levels in sugar solutions before they are moved to the onion seed fields, by developing a strain of honey bees with a preference for onion (high K) nectar, or by utilizing other species of pollinators.
The Utilization of Post-harvest Urea Sprays by Senescing Apple Leaves1
Authors: Kyung-Ku Shim , Titus J. S. , Splittstoesser W. E. 
Published: August 2022

Abstract
Senescing apple leaves absorbed 80% of applied urea in 48 hr with greater absorption in light than in darkness. The amount of urea absorbed paralleled the increase in the concn of soluble N and urea N. The bulk of the increase in soluble N was urea and the changes in total soluble N paralleled the changes in urea N. During leaf senescence, chlorophyll, total N and protein declined and much of this N was translocated into storage tissues. Trees which received a post-harvest urea spray produced a significantly greater amount of shoot growth and fruit set of apples than trees receiving no urea or a soil application of urea. The yield was not significantly different between trees receiving a 5% urea spray and trees receiving the soil application of urea. However, the efficiency of N utilization by a 5% urea spray was 4-fold greater than the soil application.
Effect of Various Endosperm Mutants on Oil Content and Fatty Acid Composition of Whole Kernel Corn (Zea mays L.)1
Authors: Flora L. F. , Wiley R. C. 
Published: August 2022

Abstract
Oil content as extracted with chloroform - methanol ranged from 5.2 to 18.4% among the 12 mutant genotypes examined. GLC analysis of the methyl esters of the corn oil fatty acids showed widely significant differences in composition among the genotypes. Action of the opaque-2 gene on the inbred caused the greatest decrease in oil content and greatest increase in the proportion of polyunsaturates. The brittle-2 gene caused the greatest increase in oil content and greatest decrease in the proportion of polyunsaturates. A positive relationship was evident between saturated and oleic acids and oil content. An inverse relationship was evident between polyunsaturated acids and oil content.
Effect of Soil Temperature on Growth and Development of Some Woody Plants1
Authors: William Barr , Harold Pellett 
Published: August 2022

Abstract
Soil temp resulting in greatest root growth was generally lower than the soil temp resulting in greatest top growth. Roots produced at low soil temp were whiter, more succulent, thicker, and had fewer lateral roots than those produced at higher temp. Increased soil temp resulted in greater water use. Soil temp also influenced mineral content of the top.
Ozone Induced Foliar Injury in Lettuce and Radish Cultivars1
Authors: Reinert Richard A. , Tingey David T. , Carter Hershell B. 
Published: August 2022

Abstract
Eight lettuce and 9 radish cvs. were exposed for 1.5 hr to 70 and 35 pphm ozone, respectively, and ranked according to their sensitivity. ‘Dark Green Boston’ was the most sensitive while ‘Great Lakes’ and ‘Black-Seeded Simpson’ were the least sensitive of the lettuce cvs. tested. ‘Cherry Belle’ was the most sensitive and ‘Icicle’ was the least sensitive of the radish cvs.
Fruit Set and Development in the Pear: Extractable Endogenous Hormones in Parthenocarpic and Seeded Fruit1
Authors: Gil Gonzalo F. , Martin George C. , Griggs William H. 
Published: August 2022

Abstract
Flowers of cvs. Winter Nelis and Bartlett contained an equivalent amount of an acidic, auxin-like substance, which decreased in the following 30 days. Thereafter, until 70 days after full bloom (AFB), the substance increased in parthenocarpic ‘Bartlett’, remained relatively constant in seeded ‘Bartlett’, and declined in ‘Winter Nelis’. A neutral auxin-like promoter was detectable in flowers of the 2 cultivars, reaching a maximum between 40 and 65 days AFB. Also, flowers and fruitlets of both cultivars contained extractable gibberellin-like substances which were in greatest abundance about 25 days AFB. The concn of these GA-like promoters at this time was greater in parthenocarpic ‘Bartlett’ fruits than in seeded fruits of either cultivar. Relatively large amounts of an abscisic acid-like (ABA-like) inhibitor were present in ‘Bartlett’ and ‘Winter Nelis’ fruits for a short time AFB. The concn subsequently decreased in both cultivars, but in ‘Winter Nelis’ it increased again toward maturity. Pear extracts contained a bound inhibitor which was active after hydrolysis with β-glucosidase. Seeds of both cultivars and unfertilized ovules of parthenocarpic ‘Bartlett’ fruits had similar levels of an ABA-like inhibitor which increased concurrently with fruit growth. Inhibitors are present throughout fruit development, in contrast to promoters, which occur in sequential order.
Variation in Essential Leaf Oil Components of Citrus Due to Stubborn Disease and Leaf Size1
Authors: Scora R. W. , Roistacher C. N. , Labanauskas C. K. 
Published: August 2022

Abstract
The comparative analysis of leaf-oil components separated by vapor phase chromatography was tested on stubborn infected and non-infected sweet orange leaves as a possible new technique for detection of stubborn disease of citrus. Three leaf-oil components: citronellol, nerol, and geraniol were found reduced in the stubborn infected leaves, but the reduction was shown to be related to the smaller leaf size and not due to the stubborn pathogen. However, one component, linalool, showed an increase in stubborn or stunt infected leaves relative to respective controls. This increase was not related to leaf size, but probably due to the presence of the pathogen.
Influence of Genotype, Date of Sampling, and Age of Plant on Leaf Chemical Composition of Red Raspberry (Rubus idaeus L.)1
Authors: John Matt K. , Daubeny Hugh A. 
Published: August 2022

Abstract
Leaf B, Ca, S, and Mo levels differed markedly in 14 red raspberry genotypes, and significant differences of lesser magnitude occurred for N, P, K, Mg, Na, Zn, Fe, Sr, and Cd. Levels of Mn, Al, and Cu were not significantly affected by genotypes. All elemental concn, except those of Mg and Mo, were influenced significantly by sampling date in ‘Willamette’. Age of plant had little effect on leaf chemical composition.
Effects of Population Density, Plant Arrangement, and Fertilizers on Yield of Sweet Corn1
Authors: Mack H. J. 
Published: August 2022

Abstract
Sweet corn yields increased 35 to 55% as plant population increased from about 4,900 to 21,000 plants per ha under irrigated conditions. Ear wt was 10 to 15% less at the higher populations. Greatest difference in yield usually occurred as row spacing was reduced from 90 to 30 cm. Row spacing affected yield less than population. Some of the highest yields were from 30 × 30 cm spacings in equilateral triangles. Triangular spacing as close as 20 × 20 cm (46,000 plants per ha) produced smaller ears, more culls and lower yields. There were no significant interactions of fertilizer rates and populations on yield; however, minimum fertilizer rates were as high or higher than most commercial applications. Yields of ‘Jubilee’ were more favorably affected by narrow row spacings and higher populations than ‘Golden Cross Bantam’.
Inheritance of a Radiation-induced Light Sensitive Mutant of Cucumber1
Authors: Whelan Ernest D. P. 
Published: August 2022

Abstract
A mutation with a pleiotropic effect was obtained from progeny of cucumber seed exposed to 16,000 rads of gamma radiation. Mutants were marked in the seedling stage by pale color and reduced size of cotyledons. Leaves of mutant plants had normal color but the plants grew slowly. Height of plant, length of internodes and petioles, size of flower, leaves, and fruit were noticeably smaller than normal plants. The mutation was recessive and monogenic. Maternal effects were not evident and no linkage was detected with a gene affecting cotyledon bitterness. The mutants were affected by high light intensity, and regardless of plant age, became senescent and died within 7 days following exposure to full sunlight. The gene is designated ls (light sensitive).
Abscission Induction in the Olive by Cycloheximide1
Authors: Hartmann Hudson T. , El-Hamady Mostafa , Whisler John 
Published: August 2022

Abstract
Cycloheximide (CHI) at 20 to 30 ppm caused olive fruit abscission, and at higher concn, leaf abscission. Water potential in the tree was a strong factor influencing CHI-induced abscission. Reducing water loss by the prior application of antitranspirants (AT) greatly increased abscission due to cycloheximide. In addition, AT stimulated ethylene production resulting from CHI application. Prior application of a wax-type antitranspirant reduced fruit injury from cycloheximide. Increasing temp, from 4.5°C to 29.5°C (40° to 85°F), stimulated abscission due to cycloheximide. Up to 25% leaf abscission was tolerated without interfering with subsequent flower formation.