bluuebunny/crossref_metadata_2025 huggingface dataset:
Postharvest Variation in Composition of Soursop (Annona muricata L.) Fruit in Relation to Respiration and Ethylene Production1
Authors: Paull Robert E.
Published: August 2022

Total soluble solids, ethanol insoluble fraction, pH, titratable acidity, total phenols, total ethanol-soluble sugars, ascorbic acid, respiration, and ethylene production were determined sequentially in individual soursop fruits from the day of harvest until the start of fruit breakdown. Total soluble solids increased from about 10° Brix to near 16° Brix during 3 days of ripening. Fruit pulp pH declined from 5.8 to 3.6 with a concomitant increase in titratable acidity over the same ripening period. Penetration force was high, generally greater than 7.5 kg, in the preclimacteric stage and then declined to less than 0.5 kg during ripening. Total phenols declined during ripening to one-third of the preclimacteric levels, while total ethanol-soluble sugars and ascorbic acid increased twofold and elevenfold, respectively. The maximum respiration rate was 108 ml/kg·hr. Ethylene production increased 24–48 hr after the fruit climacteric was initiated. The optimum eating stage occurred at day 5 to 6 from harvest at the peak of ethylene production. At a later stage, the fruit was more bland with a slight off-odor; this correlated with a decline in the titratable acidity and total phenols.
Genotype, Soil, and Climate Effects on Sensory and Objective Components of Carrot Flavor1
Authors: Simon P. W. , Peterson C. E. , Lindsay R. C.
Published: August 2022

The flavor of raw carrots (Daucus carota L.) was largely influenced by genetic variation, with dominance for desirable flavor attributes (high sweetness, low harsh flavor). Quality characteristics of plants grown under controlled temperature, relative humidity, daylength, and light intensity were comparable to those of plants grown in the simulated natural climate. Climate had a major influence on carotenoid levels. Terpinolene was the most abundant volatile terpenoid, and it affected harsh flavor, sweetness, and preference. Total sugar levels also influenced sweetness.
Ethanol, Alcohol Dehydrogenase, and Pyruvate Decarboxylase in Storage Roots of Four Sweet Potato Cultivars during Simulated Flood-damage and Storage1
Authors: Chang Ling A. , Hammett Larry K. , Pharr David M.
Published: August 2022

Flood-damage was simulated by submerging freshly harvested storage roots of 4 cultivars of sweet potato (lpomoea batatas (L.) Lam) under water for 48 hours. Root ethanol accumulation (μmoles/g fresh weight) for each cultivar was: ‘Centennial’, 38.6; ‘Jasper’, 42.9; ‘Jewel’, 48.8; and ‘Caromex’, 74.4. Storage losses due to rotting and accelerated weight loss were highest in ‘Caromex’ and second highest in ‘Jewel’. The amount of ethanol formed was not correlated with the apparent activity of either pyruvate decarboxylase or alcohol dehydrogenase. Cultivars differed upon removal from anaerobic conditions in their ability to metabolize accumulated ethanol. Cured roots of the 2 tolerant cultivars eliminated ethanol earlier than those of the 2 susceptible cultivars after anaerobic treatment. Thus, flood-damage to sweet potato storage roots may involve at least 2 factors, the rate of ethanol accumulation due to anaerobic treatment and the subsequent lag period and extent of metabolism of accumulated ethanol upon removal of anaerobic conditions.
Net Photosynthesis and Transpiration of Sun- and Shade-grown Ficus benjamina Leaves1
Authors: Fails Barbara S. , Lewis A. J. , Barden J. A.
Published: August 2022

Suitable conditions for determining net photosynthesis (Pn) of individual sun- and shade-grown leaves of weeping fig (Ficus benjamina L.) were 21°C dew point and an air flow rate between 1 and 3 liters/min. A diurnal trend in Pn occurred for sun leaves, with maximum rates between 0800 and 1200 hr; shade leaves did not decline in Pn until mid-afternoon. Leaves which originated from nodes 4 through 10 (from the shoot apex) did not differ in Pn, transpiration (Tr), specific leaf weight (SLW), or leaf water content. Shade-grown leaves had a photosynthetic advantage over sun-grown leaves at levels of photosynthetically active radiation (PAR) below 77 μE m−2s−1, whereas at PAR levels above 100 μE m−2s−1 the reverse was true. Sun-grown leaves had higher Tr rates than shade grown leaves at all PAR levels used.
Uptake and Translocation of [14C-ethyl] Labeled (2-chloroethyl)methylbis(phenylmethoxy)silane [CGA-15281] in the Peach1
Authors: Couvillon G. A. , Seeley S. D. , Kays S. J.
Published: August 2022

[14C-ethyl] labeled (2-chloroethyl)methylbis(phenylmethoxy)silane (CGA-15281) was applied to fruit and leaves of 4-year-old ‘Bicentennial’ peach trees [Prunus persica (L.) Batsch]. Virtually none of the parent material moved into the fruit or was taken up and transported in vegetative tissue. Of the small amount found within the vegetative tissue, there was equal distribution between acropetal and basipetal movement. The compound appears to act through the release of ethylene which penetrates the tissue rather than uptake of the parent molecule and subsequent release.
Regulation of Growth and Flowering in Aguilegia × hybrida Sims1
Authors: Shedron Karen G. , Weiler T. C.
Published: August 2022

Cold temperature treatments stimulated inflorescence formation of Aguilegia × hybrida at the 12-leaf stage. Long photoperiods slightly advanced flowering further, but caused petiole elongation. Sprays of butanedioic acid mono-2,2-dimethylhydrazide (daminozide) at 2,000 mg/liter effectively prevented petiole elongation.
Sink Strength of Fruits of Two Tomato Genotypes Differing in Total Fruit Solids Content1
Authors: Hewitt J. D. , Dinar M. , Stevens M. A.
Published: August 2022

Mobilization of carbohydrates to fruits of 2 genotypes of tomato (Lycopersicon esculentum Mill.) differing in total fruit solids content, LA 1563 (1563) and ‘VF145B-7879’ (‘7879’), was investigated. On the basis of 2 separate studies, fruits of 1563, the higher solids genotype, appeared to be stronger sinks for assimilates than fruits of ‘7879’. LA 1563 partitioned a significantly larger percentage of 14C to the fruits than ‘7879’. Fruits of 1563 took up more 14C-sucrose from agar medium than ‘7879’ fruits, both on the basis of total uptake and specific activity. Starch was found at higher levels in fruits of 1563 than in those of ‘7879’ from 10–30 days after anthesis. No starch was detectable in either genotype 50 days after anthesis. Fruit sucrose levels tended to be lower in 1563 than in ‘7879’ throughout fruit development. The possible physiological relationships between carbon metabolism and the rate of import of assimilates by fruits are discussed.
In Vitro Production of Cacoa Seed Lipids1
Authors: Janick Jules , Wright Daniel C. , Hasegawa P. M.
Published: August 2022

Asexual embryos of Theobroma cacao L. (cacao), initiated from zygotic embryos and grown in nutrient medium with increasing sucrose concentrations, synthesized lipids with fatty acid and triglyceride composition similar to those of zygotic embryos maturing in vitro. Oleo-palmitostearin, the major triglyceride in cocoa butter, was identified in developing asexual embryos cultured in vitro. In vitro culture of asexual embryos of cacao may be a feasible system for the production of cocoa butter.
The Effect of the Ericoid Mycorrhizal Fungus Pezizella ericae (Read) on the Growth and Nutrition of Seedlings of Blueberry (Vaccinium corymbosum L.)1
Authors: Powell Conway L.
Published: August 2022

Blueberry seedlings were inoculated with Pezizella ericae and grown in peat and pumice potting mix at 3 fertilizer treatments. Fungal inoculation stimulated shoot growth and dry matter production most at 1 application of fertilizer and increased N, S, and Ca shoot concentrations by 17, 47, and 14%, respectively. Increasing application of fertilizer tended to depress mycorrhizal infection levels in inoculated plants.
Selection and Inbreeding in Amphidiploid Dendrobium (Orchidaceae)1
Authors: Bobisud C. A. , Kamemoto H.
Published: August 2022

Inbred progenies originating from the amphidiploid Dendrobium × Jaquelyn Thomas ‘Y166-1’ were produced through sellings, sibmatings, and backcrosses. An outcross was also included. Selection and inbreeding were effective in increasing flower size and improving color purity. The characters of flower size, flower color, scape length, total initiated flowers, vase life, and bud drop were primarily influenced by parental genotypes since inbreeding decline was not apparent. Continued inbreeding of individuals selected for larger, whiter flowers led to decreased numbers of racemes and shorter plants.
Leaf Nitrogen Content and CO2 Assimilation Capacity in Peach1
Authors: DeJong T. M.
Published: August 2022

Differences in the photosynthetic capacity of leaves of peach [Prunus persica (L.) Batsch cv. Golden Glory] were investigated in conjunction with their leaf nitrogen and phosphorus content. Photosynthetic CO2 assimilation expressed on a leaf area basis, mesophyll conductance, and leaf conductance to water vapor were all linearly related to leaf nitrogen content expressed on a leaf area basis (R2 = 0.908, 0.921, 0.685, respectively). Leaf intercellular CO2 concentrations tended to decrease slightly with increasing CO2 assimilation rates and leaf N contents, indicating that CO2 assimilation was not being restricted by low intercellular CO2 concentrations and leaf conductances in leaves with lower assimilation capacity. CO2 assimilation, mesophyll conductance, and leaf conductance to water vapor were also linearly related to leaf phosphorus content, but these relationships were not as clear as for leaf nitrogen content. (R2 = 0.601, 0.687, 0.324, respectively). The maximum CO2 assimilation rate per unit of leaf nitrogen for peach leaves in this experiment was between 6.0 and 7.0 nmol CO2 mg N−1 s−1.
Factors Affecting in Vitro Propagation of Rose1
Authors: Bressan P. H. , Kim Y.-J. , Hyndman S. E. , Hasegawa P. M. , Bressan R. A.
Published: August 2022

The node position from which axillary buds were isolated from shoots of rose (Rosa hybrida L.) markedly affected their growth and development in culture. Those buds nearest to and furthest from the apex either failed to develop or took the longest time to develop in culture compared to those buds in the middle portion of the stem. Benzylamino purine (BA) at low concentrations (0.03 to 0.3 mg/liter) stimulated the development of the axillary buds of ‘Gold Glow’ but not of ‘Improved Blaze’. A photon flux density (400-700 nm) of 17μE m−2 s−1 for 12 to 24 hours daily was optimum for the stimulation of shoot multiplication, while 66 μE mm−2s−1 for 12 to 24 hr was optimum for root initiation and for subsequent successful transplantation to soil of tissue culture-derived plants. A constant temperature of 21°C resulted in the highest rate of shoot multiplication and root initiation. Plants which initiated roots at 16, 21, or 26° had the highest level of transplant survival. An alteration in the temperature of the 8-hr dark period from 21° did not increase shoot multiplication, although root initiation was enhanced by lowering the night temperature to 11 or 16°. Histological analysis indicated that shoot multiplication of rose shoots occurs through the growth and development of axillary buds. The development of axillary buds is apparently under the repressive influence of the shoot apex, because physical excision of the apex or application to the shoot apex of 2,3,5-triiodobenzoic acid (TIBA) facilitated axillary bud development. Root initiation was affected markedly by the length of time that cultures had been maintained on shoot multiplication medium prior to transfer to rooting medium. This effect may be attributable to the BA in the shoot multiplication medium which may have accumulated in the tissue. If the endogenous cytokinin level is too high, root initiation may be inhibited and if it is too low the shoot undergoes senescence before it becomes cytokinin-autonomous, which occurs after root initiation.
Effects of Irrigation Practices on Vine Growth, Yield, and Quality of Muskmelons1
Authors: Pew W. D. , Gardner B. R.
Published: August 2022

Higher yields, larger fruit size, and earlier maturity were achieved in muskmelons (Cucumis melo L.) by irrigating when soil moisture tensions at the 25-cm depth reached 50 and 75 kPa compared with tensions of 25 kPa. More fruits were culled in the wet treatment due to decay while the drier treatments produced more fruits with growth cracks. Melons from the drier treatments were higher in soluble solids. Irrigation did not affect the other storage and shipping quality factors measured. A prethinning irrigation caused restricted root development, vine growth, fruit size, and yield.
Simulated Acid Rain Effects on Zinnia as Influenced by Available Nutrients1
Authors: Keever G. J. , Jacobson J. S.
Published: August 2022

Greenhouse-grown plants of Zinnia elegans Jacq. were exposed to simulated sulfuric acid rain 30 minutes per day twice a week for 6 weeks at pH 2.8, 4.0, and 5.6. Injury occurred primarily to older, mature leaves and cotyledons at pH 2.8 and 4.0 and to ray flowers at pH 2.8. Plants supplied with higher levels of Hoagland’s nutrient solution grew more rapidly, contained greater quantitities of foliar K, P, and Ca, and exhibited more foliar injury after exposure to acidic simulated rain (SR). Dry weight of plants given full-strength nutrient solution (highest level) was depressed at pH 2.8 and increased at pH 4.0 relative to pH 5.6. Loss of 86Rb by leaching from foliage was significantly increased at pH 2.8, but no differences in total foliar content of K, P, and Ca were detected.
Axis Elongation from Tissue-culture-generated Bulblets of Lilium longiflorum Thunb.1
Authors: Stimart Dennis P. , Ascher Peter D. , Wilkins Harold F.
Published: August 2022

Up to 50% of bulblets generated in vitro at 30°C from bulbscale explants of Lilium longiflorum ‘Ace’ produced an elongated axis in the 14 weeks after removal from tissue culture and potting in vermiculite. None of the ‘Ace’ bulblets produced in vitro at 25° and none of the ‘Nellie White’ bulblets produced in vitro at either 25° or 30° formed an elongated axis. Increased length of time that ‘Ace’ bulbs were stored at 4° before explanting as well as immersing bulblets generated in vitro at 30° in water at 45° for 1 hour before potting increased the percentage of bulblets with an elongated axis. Axis elongation was not related to bulblet size or to position of scale used for explanting (inner vs. outer bulb scale). Exposing ‘Ace’ bulblets generated at 30° to 3 or more weeks at 4° reduced the percentage of bulblets with an elongated axis to zero. Treatment of chilled bulblets for 2 hours in water at 45° did not reverse the effect of cold.
Factors Affecting the Recovery of Juice and Anthocyanin from Cranberries1
Authors: Sapers G. M. , Jones S. B. , Maher G. T.
Published: August 2022

Factors affecting anthocyanin recovery in juice from pressed cranberries (Vaccinium macrocarpon Ait.) were investigated under laboratory conditions. Anthocyanin recovery was unaffected by cultivar, total anthocyanin content, or juice yield. Variability in anthocyanin recovery was attributed to the heterogeneity of berry samples analyzed for total and juice anthocyanin and to differences in the efficiency of pigment extraction by juice liberated during pressing. Freeze-thaw treatment of cranberries increased juice yield by as much as 50% and juice anthocyanin content by as much as 15-fold. Microscopic observation of changes at the cellular level resulting from freeze-thaw treatment supported the juice yield and pigment recovery data. Anthocyanin recovery could be increased by double pressing and by tissue homogenization.
Rootstock Influence on Growth, Yield, and Survival of ‘Loring’ Peach Trees on an Old Peach Site1
Authors: Dozier W. A. , Carlton C. C. , Short K. C. , Snell J. M. , McGuire J. A. , Evans C. E.
Published: August 2022

Three rootstock—Elberta seedling (Elb), Lovell seedling (Lov), and Vila Fria seedling (VF)—were evaluated on an old peach-orchard site to determine their susceptibility to nematodes and their effect on growth, yield, survival, and foliar nutrient content of ‘Loring’ peach [Prunus persica (L.) Batsch]. During the first 6 years of the orchard's life, mortality rates of the trees were 18% (Elb), 21% (Lov), and 47% (VF). Rootstock did not affect tree height, spread, trunk circumference, or yield the first 3 crop years. However, Lov produced higher yields the 4th crop year and had a greater cumulative yield for the first 4 crop years than Elb or VF. When tree loss was taken into account, tree yield per hectare did not differ with Lov and Elb but was lower with VF. Rootstock did not affect nutrient level in the foliage. Nematode populations were low in the orchard and were unaffected by rootstock. Tree loss, yield differences, and cropping efficiency of trees on the different rootstock could not be accounted for by foliar nutrient levels, nematode populations, tree vigor, or size.
Phthalimide-inhibition of the Ethylene Effect on Sex Expression in Monoecious Cucumber Plants1
Authors: Xu Shao Ying , Bukovac Martin J.
Published: August 2022

The phthalimide 1-(1-cyclohexene-1,2-dicarboximido)-cyclohexanecarboxamide delayed formation of pistillate flowers in a monoecious cucumber (Cucumis sativus L. cv. Sumter). A saturating dose completely inhibited ethylene-enhanced pistillate flower formation in respect to number of nodes preceding the first pistillate flower and number of pistillate flowers produced per plant.
Adaptation Studies on Lima Bean Accessions in Colombia
Authors: Lyman J.M.
Published: August 2022

Thirty-six climbing accessions of lima bean (Phaseolus lunatus L.) were grown on trellises with minimal chemical inputs in 5 trials at 4 Colombian sites. Mean dry-seed yield of all accessions at all 4 sites was 2.6 mt/ha. Mean yield at the least favorable site was 1.7 mt/ha; at the most favorable site it was 4.8 mt/ha. Although growth was affected adversely on a soil with pH 4.2, the mean yield was 2.5 mt/ha. Mean daily dry-seed productivity rates of all accessions ranged from 15.1 kg/ha/day to 44.1 kg/ha/day for the several locations, in some cases exceeding rates reported for common beans and other legumes at the same location. Mean yield and number of pods per plant varied significantly among sites, dependent upon temperature and soil differences. Days to flower and to dry-seed harvest were relatively stable traits. No relationship was found between yield and seed-coat color. Production constraints were rainfall distribution and acid, phosphorus-deficient soils. These studies demonstrated high productivity of lima beans under adverse and favorable climatic and soil conditions in Colombia
Modeling Cold Hardiness of Red-osier Dogwood
Authors: Kobayashi Kent D. , Fuchigami Leslie H. , Weiser Conrad J.
Published: August 2022

Effects of temperature on cold acclimation and deacclimation of red-osier dogwood (Cornus sericea L. syn. Cornus stolonifera Michx.) plants were determined at different stages of plant development. Results were used to develop models for predicting stem hardiness. Acclimation and deacclimation rates were related to temperature and plant developmental stage (expressed as degree growth stage, °GS). Decreasing temperature promoted increasing acclimation. Maximum acclimation rates in the temperature range of 5° to 20°C occurred at maximum rest (270°GS). During the decreasing rest phase (270 to 315°GS), deacclimation occurred at temperatures from 7° to 20°C. At earlier stages of development (315° and 335°GS) during the quiescent phase (315 to 360°GS), 5°C was the only temperature that promoted hardiness, whereas at a later stage (341°GS) all temperatures tested caused deacclimation. The models, using bihourly temperatures and accumulating °GS, predicted hardiness within an average deviation of 4.7°C.
Some Effects of AVG on Fruit Set, Fruit Characteristics, and Vegetative Growth of Apple Trees
Authors: Greene Duane W.
Published: August 2022

Preharvest application of 500 ppm aminoethoxyvinylglycine (AVG) delayed bloom and increased initial fruit set of mature ‘McIntosh’, ‘Spartan’, and ‘Spencer’ apple trees (Malus domestica Borkh.). Final fruit set was enhanced for ‘Spencer’ by a slight suppression of ethylene evolution by flowers harvested during anthesis. AVG reduced fruit weight but increased the fruit length/diameter (L/D) ratios for all 3 cultivars. Vegetative growth effects were confined to an enhancement of spur elongation. Fruit set was improved on ‘Richared Delicious’ and ‘Red Spur Delicious’ by fall (preharvest) and by full-bloom AVG sprays. Postbloom sprays were ineffective. AVG reduced fruit weight but enhanced fruit L/D ratios. A fall treatment of 500 ppm AVG increased both the number and average length of spur shoots on ‘Richared Delicious’. Young ‘Red Spur Delicious’ trees responded to bloom-time AVG (250, 500 ppm) and 6-benzylamino purine (BA) plus gibberellic acid (GA4+7) sprays (500 ppm each) with markedly increased feathering and an overall increase in extension growth and number of leaves per lateral growing point. However, these same treatments reduced the size and weight of individual leaves.
Effect of Chemical Thinners on Fruit Set and Fruit Characteristics of AVG-treated Apples
Authors: Greene Duane W.
Published: August 2022

Initial fruit set was increased on ‘Delicious’ and to a lesser extent on ‘McIntosh’ following a 500 ppm preharvest aminoethoxyvinylglycine (AVG) treatment. Final fruit set was increased by AVG only on ‘Delicious’. One day following a chemical thinner application, ethylene production in check and AVG-treated limbs was similar. AVG did not inhibit naphthaleneacetic acid (NAA) induced ethylene production from either fruits or leaves. June drop from AVG-treated limbs appeared to be increased. Carbaryl reduced fruit set on AVG-treated limbs to the same level as on check limbs, while NAA at 15 ppm on ‘Delicious’ reduced the crop load below that of check limbs. AVG reduced fruit size on ‘Delicious’ (which was not overcome by thinners) but did not reduce fruit size on ‘McIntosh’. The length/diameter (L/D) ratios of ‘McIntosh’ and ‘Delicious’ were increased by AVG, but NAA reduced the L/D ratios on both check and AVG-treated limbs. NAA increased the number of “pygmy” fruit on ‘Delicious’, and when combined with preharvest AVG, the number was twice as great as when NAA was applied alone.
Distinguishing Camellia L. Species Using Dorsal Leaf Surface Impressions
Authors: Ackerman W.L. , Zhang Ao-luo
Published: August 2022

The dorsal (lower) surfaces of leaf samples taken from 38 species of Camellia were examined for distinctive characters which might serve as an aid in taxonomic characterization of subgenera and sections in Camellia. A simple technique involving cyanoacrylate adhesives was used to prepare microscope slides for examination with a light microscope equipped with differential interference contrast optics. Specific characteristics studied included the distribution of stomata, the shape and size of guard, subsidiary, and other epidermal cells, and the presence or absence of epidermal hairs and gland and corky cells. Characteristics of epidermal cells on the dorsal surfaces of Camellia leaves can serve as a technique for the classification of species and cultivars and in the verification of species purity or determination of hybrid status.
Inhibition of Lycopene Synthesis in Tomato Pericarp Tissue by Inhibitors of Ethylene Biosynthesis and Reversal with Applied Ethylene
Authors: Edwards Julie I. , Saltveit Mikal E. , Henderson Warren R.
Published: August 2022

Inhibitors of ethylene biosynthesis—aminoethoxyvinylglycine, aminooxyacetic acid, and α-aminoisobutyric acid—inhibited ethylene and lycopene biosynthesis in 1.5-cm disks of excised pericarp tissue of tomato (Lycopersicon esculentum Mill. cv. Michigan-Ohio Hybrid). Application of 10 μl/liter ethylene promoted normal lycopene synthesis, but did not stimulate ethylene synthesis.
Effects of Inhibitors of Ethylene Synthesis or Action, GA4+7, and BA on Fruit Set of Apple, Sour Cherry, and Plum
Authors: Dennis F.G. , Archbold D.D. , Vecino C.O.
Published: August 2022

Several inhibitors of ethylene synthesis or action were tested to determine their effects on fruit set of apple (Malus domestica Borkh.)9 sour cherry (Prunus cerasus L.) and plum (P. domestica L). None increased set of cherry or plum and only aminoethoxyvinylglycine (AVG) increased set of apple. This compound reduced set in cherry. GA4+7, benzylamino purine (BA), and Promalin (GA4+7 + BA) were ineffective in increasing fruit set of apple with or without AVG, and GA4+7 was likewise ineffective on cherry. AVG (50 to 200 ppm) increased set of apple by as much as 10-fold when applied between pink and petal fall.
Physiological and Compositional Changes in Orange Fruit in Relation to Modification of their Susceptibility to Penicillium italicum by Ethylene Treatments
Authors: El-Kazzaz M.K. , Chordas A. , Kader A.A.
Published: August 2022

Exposure of orange fruit to 1000 μl/liter C2H4 at 20°C for 2 to 6 days before inoculation with Penicillium italicum Wehmer reduced fungal growth as indicated by lesion diameter and glucosamine content. Respiration rates were stimulated by C2H4 treatments and fungal inoculation, which also increased C2H4 production rate. Ethylene treatments with or without inoculation did not influence soluble solids, pH, titratable acidity, or total phenolics content of fruit juice. Total phenolics of the rind increased in uninoculated fruit, but not in inoculated fruit, in response to C2H4 treatment. No polyphenol oxidase activity was detected. Phenylalanine ammonia-lyase activity exhibited a significant increase in rind of uninoculated fruit, but not in inoculated fruit which were subjected to C2H4 for 6 days followed by 6 days in air at 20°C.
Production Potential and Survival of Fall- and Spring-seeded Asparagus
Authors: Dufault Robert J. , Greig James K.
Published: August 2022

Seed of asparagus (Asparagus officinalis L.) germinated normally after 2 months of constant freezing (-10°C) or chilling (4°) under water-saturated conditions in laboratory germination studies. However, temperatures cycling weekly from chilling to freezing for 2 months reduced germination to less than 50%, and temperatures cycling weekly from warm (21°/16°, day/night) to chilling to freezing for 2 months reduced germination to 0. The stands of asparagus, field-seeded in November and December, were reduced 85% by winterkill in comparison to spring seeding in March and April. Seeding densities from 10 to 40 seed/m did not compensate for stand loss. The greatest contributor to winterkill apparently was seed rot. March seeding increased plant height, but not crown quality or the number of shoots initiated in comparison to conventional April seeding. High seeding densities did not reduce plant growth or crown yields in the spring plantings. Stand establishment was not different between the spring planting dates. Early March seeding at high densities is recommended.
Growth Inhibitors in Xylem Exudates of Persian Walnuts (Juglans regia L.) and their Possible Role in Graft Failure
Authors: Prataviera A.G. , Kuniyuki A.H. , Ryugo K.
Published: August 2022

When walnut trees were bark-grafted leaving nurse-limbs, xylem exudation was observed at a few slashes made low on the tree but not at graft junctures. Scions grew equally well on trees with slashes (74%) as those without slashes (86%). When the same treatments were made without nurse-limbs, 83% of the scions grew where exudates did not appear but only 21% grew where xylem sap exuded nearby. No dormant patch-bud placed in August-September grew the following spring if the sap flowed from any side of the patch, whereas 96% grew where no exudation occurred. Analysis of the xylem exudate revealed the presence of substances which inhibited growth of walnut calli and cucumber seedlings. A strong zone of inhibition on paper chromatograms coincided with the Rf of juglone, a powerful toxin which was identified by absorption spectrophotometry.
Interactions between Air and Root Temperatures on Greenhouse Tomato: I. Growth, Development, and Yield
Authors: Gosselin André , Trudel Marc J.
Published: August 2022

Greenhouse tomato plants (Lycopersicon esculentum Mill. cv. Vendor) were grown at 5 root temperatures (12°, 18°, 24°, 30°, and 36°C) and 4 night air temperatures (12°, 15°, 18°, and 21°) for 3 months. Low root and low night air temperatures contributed to high root dry weight. However, under warm soil temperature conditions (30° and 36°), roots were most efficient in sustaining shoot growth and in absorbing water as indicated by the percentage of shoot dry weight. Shoot growth was maximum at 15° night air temperature and 30° root temperature. High root temperatures are required at low night air temperature for maximum shoot growth. Maximum yields were obtained at a combination of 18° night air temperature and 24° root temperature. An increase in soil temperature partly offsets the detrimental effects of low night air temperatures.
Effects of Processing upon Objective and Sensory Variables of Carrots
Authors: Simon P.W. , Lindsay R.C.
Published: August 2022

Four hybrids of carrot (Daucus carota L.) were analyzed raw, fresh-cooked, canned-cooked, or frozen-cooked for sensory and objective parameters. Processing reduced the carotenoid and volatile terpenoid concentrations of all hybrids. Relative to raw carrots, sugar content was reduced in canned-cooked and frozen-cooked carrots, but was increased in fresh-cooked samples. Depending on the hybrid, 6% to 32% of the free sugar was reducing sugar in raw samples; however, sugars in processed samples were 15% to 33% reducing sugar. Fresh-cooked and frozen-cooked carrots exhibited a 10-fold reduction in shear pressure texture relative to raw texture, while canned carrots had a 30-fold reduction. Harsh flavor was reduced greatly by canning and freezing, but was not reduced as much in fresh-cooked samples. These differences in harsh flavor could be accounted for by variation in volatile terpenoid levels. Differences in sweetness found between raw sampling hybrids also were observed for corresponding samples after processing. Reducing sugars and volatile terpenoids contributed to variation in sweetness and preference.
Quality of Apple Fruit from a High Density Orchard as Influenced by Rootstocks, Fertilizers, Maturity, and Storage
Authors: Fallahi Esmaeil , Richardson D. G. , Westwood Melvin N.
Published: August 2022

Fruit quality of ‘Starkspur Golden Delicious’ apples (Malus domestica Borkh.) on 6 rootstocks [Seedling, Mailing (M) 1, M ailing Merton (MM) 106, M 7, OAR 1, M 26] grown in a high density orchard at 2 levels each of K and N was studied at 3 harvest dates and after 6 months of 0°C storage from 1980 to 1982. Fruit on OAR 1 rootstock had greater soluble solids, more yellow color at harvest and after storage and were relatively firmer at harvest, but were smaller than those from other rootstocks. Fruit on M 7 had lower soluble solids than most of the other rootstocks at harvest time. Fruit from MM 106 had a lower incidence of breakdown in storage than most others. Crop load influenced both harvest and storage quality. Fruit on M 26, which had a light crop in 1981, were larger, yellower, and had higher soluble solids, and also had more storage breakdown (about 20%) and bitterpit (about 12%) than other rootstocks. Rootstocks or fertilizers did not affect fruit respiration. Little effect of K fertilizer was found on any quality indices, whereas high N treatments produced greener fruit than did low N.
Nodulation and Nitrogen Fixation in Cowpea as Influenced by Zinc Nutrition
Authors: Marsh Dyremple B. , Waters Luther
Published: August 2022

Zinc concentration, nitrogen fixation (C2H2 reduction), nodulation and dry-matter distribution in the early maturing cowpea [Vigna unguiculata (L.) Walp] line Mn 13 were examined at 5 levels of Zn (0.0, 0.6, 1.5, 2.5 and 5 ppm) under field and greenhouse conditions. Significant increases in nodule number, nodule dry weight, and acetylene reduction occurred when plants received the higher Zn levels. In all plant parts sampled, there was increased Zn accumulation with increased Zn application, with roots having the maximum accumulation. Seeds per pod and seed yield (kg/ha) were highest at the higher applied Zn levels. The yield response to added Zn was reflected primarily by an increase in the number of seeds per pod. Zinc nutrition is important to the nodulation and fixation processes, and it may affect both Rhizobium nutrition and dry-matter accumulation.
Effect of Calcium on Ripening, Respiratory Rate, Ethylene Production, and Quality of Avocado Fruit
Authors: Eaks Irving L.
Published: August 2022

The effect of Ca between 0.05 and 5.0 m on days to ripen, respiratory rates, rates of ethylene evolution, and external and internal quality of ‘Fuerte’ and ‘Hass’ avocado fruit at 20°C when placed directly at 20° or at 20° after 1, 3, and 5 weeks storage at 0° and 5° was determined. Dipping fruit in Ca solutions had no significant effect on these responses. The results discussed are for vacuum-infiltrated fruit. Days to ripen was increased and respiratory rates and rates of ethylene evolution were reduced as the Ca concentration increased. At 0.4 and 0.5 m Ca, no detectable climacteric occurred, essentially no ethylene was produced and the fruit failed to ripen. Exogenous ethylene or propylene exposure for 2 days resulted in typical stimulation of respiratory rates, ethylene production, and ripening of untreated fruit. Treatment with Ca reduced each response. Storage experiments indicated that Ca reduced internal chilling injury symptoms and increased external symptoms. Commercial Ca treatment of avocados to delay ripening and reduce chilling injury symptoms does not seem practical, because of the necessity to vacuum-infiltrate the Ca solution into the fruit and the adverse effect on external quality when ripened after storage.
Influence of Rootstocks and Fertilizers on Ethylene in Apple Fruit during Maturation and Storage
Authors: Fallahi Esmaeil , Richardson Daryl G. , Westwood Melvin N.
Published: August 2022

Internal ethylene of attached fruit of ‘Starkspur Golden Delicious’ apple as influenced by 6 rootstocks: Seedling, Mailing (M1) 1, Mailing Merton 106 (MM 106), M 7, OAR 1, M 26, at 2 levels each of soil-applied K and N were measured during maturation for 2 years (1980 and 1981). Ethylene evolution of detached fruit as a result of these treatments also was measured after 2.5 months of storage at 0°C in 1981. Internal ethylene in the attached fruit was less than 0.1 μl·liter-1 in late September and early October and began to rise between 9 Oct. and 15 Oct. Internal ethylene increased in all treatments, almost at the same time in 1980. In 1981, ethylene in the fruit on OAR 1 began to increase 9 days later than in the other rootstocks. However, levels of ethylene in the fruit were relatively low on OAR 1 and high on M 26 as compared to those on other rootstocks in late October 1980 and 1981 and during poststorage 1981 samplings. Ethylene levels in fruit from other rootstocks were similar. Because of these variable effects of rootstocks, and the effects of a low field temperature in reducing internal ethylene levels, field sampling of internal ethylene levels was an unreliable indicator of the proper harvest time, as measured by other maturity indices. No consistent influence of K or N applications was found in the internal ethylene of the attached fruit; however, high N applications increased ethylene evolution after storage.
Pathways of Calcium Penetration through Isolated Cuticles of ‘Golden Delicious’ Apple Fruit
Authors: Glenn G. M. , Poovaiah B. W. , Rasmussen H. P.
Published: August 2022

Cuticles from ‘Golden Delicious’ apples (Malus domestica Borkh.) were isolated enzymatically. Changes in cuticles of developing fruit at various stages were studied using scanning electron (SEM) and light microscopy (LM). Structures allowing Ca penetration through the cuticle were studied by precipitating permeating Ca in agar as it passed through the cuticle. The importance of lenticels in the penetration of Ca at 2 stages of fruit development was studied under saturated conditions using a diffusion cell. The lenticels had a significant positive effect on Ca penetration. The development of a dense network of structures resembling cracks, as well as occasional surface discontinuities, were observed in cuticles isolated from fruit harvested in September. These structures seemed to provide pathways for cuticular Ca penetration. The importance of lenticels, cracks, or other surface irregularities, and the process of diffusion in the penetration of Ca into apple fruit is discussed.
Ethylene-releasing Compounds and the Laboratory Modeling of Olive Fruit Abscission vs. Ethylene Release
Authors: Lang G. A. , Martin G. C.
Published: August 2022

A laboratory system was developed to study olive (Olea europaea L.) organ abscission (21). An improvement of the use of ethylene-releasing compounds in this system is described to provide a model for field abscission responses and characterization of ethylene release. Olive fruit began the separation process as early as 7 to 13 hr after treatment with CGA-15281 (CGA), but not until 19 to 25 hr after treatment with ethephon (ET). CGA is characterized by an immediate, substantial breakdown to ethylene, whereas ET reaches its maximum ethylene release at 12 to 18 hr after application. Ethylene release was much greater from CGA than from equimolar concentrations of ET throughout the abscission initiation period. The relation of ethylene release characteristics to control of olive fruit and leaf abscission is discussed, with the suggestion that fruit respond more rapidly to, and at shorter durations of applied ethylene than do leaves.
Properties of Ice Nuclei Associated with Peach Trees
Authors: Ashworth E. N. , Anderson J. A. , Davis G. A.
Published: August 2022

No relationship was observed between the population of ice nucleation active (INA) bacteria and the temperature at which ice formed in peach [Prunus persica (L.) Batsch] shoots. The ice nucleation temperature remained stable throughout the year, even during periods when INA bacteria were not detected. An intrinsic ice nucleating substance seemed to be responsible for initiating ice formation and limited supercooling to about —2°C. The ice nucleating agent seemed to be a constitutive component of mature wood and was stable under a range of chemical treatments. Ice nucleation was influenced by sample mass, temperature, and length of exposure. The freezing behavior of peach shoots was best described using a stochastic model of ice nucleation.
Initiation of Tomato Fruit Ripening with Copper
Authors: Rushing James W. , Huber Donald J.
Published: August 2022

A vacuum infiltration technique that allowed precise control of both infiltration rate and amount of solution administered to whole tomato (Lycopersicon esculentum) fruit was developed. Controlled volumes of 5 mm solutions of CuSO4, Cu(NO3)2, HgCl2, CaSO4, KNO3, (NH4)2C2O4, Na2HPO4, citrate and 1 mm EDTA or EGTA were infiltrated into intact, mature-green tomato fruit and evaluated with regard to their effect on the pattern of tomato ripening. Copper significantly accelerated lycopene accumulation and influenced both the timing and magnitude of climacteric ethylene production. Infiltration with HgCl2 elicited similar effects as copper, but severe phytotoxicity was observed. In contrast, CaSO4, KNO3, and chelators had no significant effect on the pattern of ripening. Copper initiated wound ethylene production in the ripening mutant rin that reached up to 50% of the wound levels observed in normal fruit, but rin was not induced to ripen.
Dormancy and Growth of American Ginseng as Influenced by Temperature
Authors: Lee Jong Chul , Strik Bernadine C. , Proctor John T.A.
Published: August 2022

American ginseng (Panax quinquefolium L.) roots have a dormancy period which can be satisfied by exposure to low temperatures of 0° to 10°C for about 100 days. Three-year-old roots of ginseng were weighed, given variable periods (≥ 50 days) of low temperature (5°C), planted in vermiculite in pots, and grown in light or dark at 5°, 10°, 15°, or 20°. After 50 to 100 days of storage at 5°, stem growth occurred at all temperatures except 20°. At this temperature, a minimum of 75 days at 5° was required to satisfy dormancy. Stem growth rate was relatively constant at 5° and 10° but increased with storage time when grown at 15° or 20°; leaf growth rate was affected similarly, except that no leaf growth occurred at 5°. If optimum cold storage and growth requirements were not met, the plants appeared abnormal and had reduced root dry weights. After 100 days of storage, the greatest growth rate was observed at 15° and 10°. Plant growth rate was the least at 5° and 20°.
Comparison of the Initiation and Development of ‘Redhaven’ Peach Flowers in Standard and Meadow Orchard Trees
Authors: Warriner Carol L. , Johnson Johnny L. , Smith Michael W.
Published: August 2022

Lateral apical meristems were collected biweekly from 15 July 1982 to 18 Mar. 1983 from 2-year-old ‘Redhaven’ peach [Prunus persica (L.) Batsch] trees grown under standard and meadow orchard cultural practices. Dissected buds were prepared for scanning electron microscope analysis, and representative samples were photographed. Meadow orchard trees were cut 20 cm above the soil immediately after fruit harvest (15 July), and thus, floral initiation and development was delayed until new growth occurred. Floral development in the standard trees began 7 weeks after harvest (late August) but did not begin in the meadow orchard trees until 13 weeks after harvest (early October). The sequence of floral development in both standard and meadow orchard trees began with petals followed by sepals, stamens, and the pistil. Standard trees produced numerous floral apices; however, floral differentiation was poor in the meadow orchard trees with only 5% to 10% of the buds initiating floral apices. The meadow orchard system thus may have limited use in central Oklahoma.
Effect of Nitrogen and Potassium on Yield, Growth, and Leaf Elemental Concentration of Pecan
Authors: Smith Michael W. , Ager P.L. , Endicott D.S.W.
Published: August 2022

Nitrogen and K were applied to 26-year-old ‘Western’ pecan [Carya illinoensis (Wangenh.) C. Koch] trees at 0, 56, 112, or 224 kg ha−1, and 0, 93, or 186 kg ha−1, respectively, for 6 consecutive years (1978–1983). There was a positive relationship between N rate and leaf N concentration and shoot growth. The number of new shoots per 1-year-old shoot was increased by N application. Yield was greater using 56, 112, or 224 kg N ha−1 than no N. Nitrogen rate was negatively related to leaf K concentration and curvilinearly related to leaf Mn concentration, but did not affect leaf Ca or Mg. Leaf P and Zn concentrations were reduced during some years by N application. Potassium application increased leaf K concentration in 1980, 1982, and 1983, but did not affect leaf K concentration in other years. Surface applied K moved to the 30–45 cm depth by 1980 and to the 45–60 cm depth by 1982. Potassium rate was positively related to leaf Mn concentration, but not leaf N, P, Ca, Mg, or Fe concentration. Annual yield was increased by K rate only in 1979, but cumulative yield was positively related to K rate.
Effects of Genetically Removing Lectin Seed Protein on Horticultural and Seed Characteristics of Common Bean
Authors: Osborn Thomas C. , Bliss Fredrick A.
Published: August 2022

The absence of seed lectin in common bean (Phaseolus vulgaris L.) was shown to be inherited as a single recessive gene and allelic to genes conditioning 6 different lectin types. In inbred backcross lines, the allele from ‘Sanilac’ (a navy class bean) for the presence of lectin was semidominant to the lectinless allele from ‘U.I. 1140’ (a Great Northern class bean) for quantity of lectin. Backcross lines with lectin (L/L) and without lectin (1/1) were developed using 2 lectinless donor parents (‘U.I. 1140’ and ‘U.I. 111', a Pinto class bean) and ‘Sanilac’ as the recurrent parent. Backcross lines and parents were grown in the field and analyzed for days to flower, seed yield, seed weight, percentage protein, and quantities of lectin and phaseolin. There were significant differences between lectin genotypes (L/L vs. 1/1) for all traits except yield, seed weight, and nonphaseolin nonlectin protein. Backcross lines without lectin had substantially higher levels of phaseolin and slightly more total protein than lines with lectin. The data suggested that phaseolin over-compensated for the absence of lectin in 1/1 backcross lines. The implications of these findings toward the nutritional improvement of bean protein are discussed.
Ethylene, ACC, Soluble Polyuronide, and Cell Wall Noncellulosic Neutral Sugar Content in ‘Eldorado’ Pears during Cold Storage and Ripening
Authors: Wang Chien Yi , Sams Carl E. , Gross Ken C.
Published: August 2022

The capacity of ‘Eldorado’ pears to ripen increased dramatically after 4 weeks of exposure to 0°C and was associated with the synthesis of ethylene by pear tissue. Endogenous levels of ACC and internal ethylene were low after harvest, but increased rapidly after 4 weeks at 0°. Exposure to 0° for 4 weeks also resulted in an increase in soluble polyuronide during subsequent ripening at 20°. In contrast, after 9 months at 0°, soluble polyuronide content showed little increase when pears were transferred to 20°, and fruit failed to soften normally even though ACC content, internal ethylene concentration, ethylene evolution, and respiration remained relatively high. The content of arabinose, galactose, and rhamnose residues in cell walls decreased substantially during the ripening period after 4 weeks or longer at 0°. These cell wall neutral sugars decreased during ripening, even after 9 months of storage at 0°, while firmness and soluble polyuronide showed little change after fruit were transferred to 20°. These data indicate that the failure of pears to soften normally at 20° after prolonged storage at 0° is not related to ethylene synthesis or to changes in cell wall noncellulosic neutral sugar content, but is probably associated with mechanisms of polyuronide solubilization. Chemical name used: 1-aminocyclopropane-1-carboxylic acid (ACC).
Effect of Various Levels of Available Water on Germination of Polyethylene Glycol (PEG) Pretreated or Untreated Tomato Seeds
Authors: Liptay A. , Tan C. S.
Published: August 2022

Germination of tomato (Lycopersicon esculentum Mill.) seeds in petri dishes at various levels of water stress was comparable, except under conditions of severe stress when a PEG pretreatment improved final percentage germination and enhanced the onset and rate of germination. At intermediate or high watering levels, PEG-pretreated seeds germinated more rapidly than untreated seeds, but final germination was not altered by PEG. Germination of seeds in soil, under controlled laboratory conditions, was similar to that in petri dishes except under the driest conditions (5% ASM) when little emergence occurred whether the seeds were pretreated or not. A majority of the seeds which failed to germinate after 2 weeks under dry soil conditions were still viable, since subsequently they could be induced to germinate by moistening the soil to 100% ASM. Water requirement of tomato seeds for optimal rate of germination was cultivar dependent; PI-341988 seeds germinated well at 60% ASM or greater, whereas ST-24 required 100% ASM for best germination.