bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluoride induced Chlorosis and Necrosis of Dracaena fragrans ‘Massangeana’1
Authors: Conover Charles A. , Poole Richard T.
Published: August 2022

Leaf mottling (chlorosis and necrosis) of Dracaena fragrans (L.) Ker-Gawl. ‘Massangeana’ was most severe on plants receiving either superphosphate or sodium fluoride (NaF). Plants with most severe leaf mottling also had highest tissue levels of fluoride (F). Application of dolomite increased pH and reduced leaf mottling on plants that did not receive F applications, but had little effect on plants receiving 180 or 360 mg F/20 cm pot. Fluoride was implicated in leaf mottling of D. fragrans ‘Massangeana’ under interior environments.
Interaction of Peach Seedlings to NO3:NH4 Ratios in Nutrient Solutions1
Authors: Edwards J. H. , Horton B. D.
Published: August 2022

Peach [Prunus persica (L.) Batsch] seedlings of ‘Siberian C’, ‘Tzim Pee Tao’, NA 8, and 152A1–2 were grown for 64 days in nutrient solutions with constant N concentration, but the ratio of NO3 to NH4 in the nutrient solution varied from 100:0 to 0:100. The greatest growth occurred when the NO3:NH4 treatment was 50:50 or 25:75. The poorest growth occurred when NO3 was the sole N source in the nutrient solution. Significant interaction of nutrient concentrations occurred with the different rootstock and N ratios in all tissues studied. The N concentration in leaves and roots was highest in seedlings grown in N treatments of 100:0 or 75:25. The concentrations of P, Ca, and Mg in the leaves, stems, and roots of all cultivars decreased with each increment increase in the NH4 concentration in the nutrient solution. The relative growth rate and N uptake rate of all seedlings increased with high NH4 concentrations. The uptake rates of P, K, Ca, and Mg were highest for NO3:NH4 treatments of 50:50 or 25:75. Chlorosis developed on margins of leaves mid-way on the main stem on all seedlings with NO3:NH4 treatments 50:50, 25:75 and 0:100. The disorder occurred in the mature leaves of all cultivars but did not affect expanding leaves.
Net Photosynthesis, Dark Respiration, Transpiration, and Stomatal Resistance of Young and Mature Apple Trees as Influenced by Summer or Dormant Pruning1
Authors: Marini Richard P. , Barden John A.
Published: August 2022

Young container-grown apple (Malus domestica Borkh.) trees and mature bearing trees were summer pruned either before or after shoot extension had ceased. Net photosynthesis, dark respiration, and transpiration of shoot leaves were increased by summer pruning, while stomatal resistance was decreased as compared to dormant pruned controls. These effects were more pronounced and of longer duration in basal leaves of container-grown trees and interior leaves of orchard trees than in distal or peripheral leaves, respectively.
Activated Carbon Protects Direct-seeded Tomatoes from Partially Selective Herbicides1
Authors: Romanowski R. R.
Published: August 2022

Activated carbon was applied in an anticrustant mixture with direct-seeded tomatoes (Lycopersicon esculentum Mill.) to protect them from diphenamid (N, N-dimethyl-2,2-diphenylacetamide) and metribuzin [4-amino-6-tert-butyl-3(methylthio)-as-triazin-5(4-H)-one] injury. Commercially acceptable weed control and increased crop safety were obtained by the application of activated carbon with both herbicides.
Conditioning Florida Grapefruit to Reduce Chilling Injury during Low-temperature Storage1
Authors: Hatton T. T. , Cubbedge R. H.
Published: August 2022

Reduction of chilling injury (CI) during 1°C storage by conditioning treatments was determined on early (1975–76 test), midseason and late (1977–78 and 1978–79 tests) ‘Marsh’ and ‘Ruby Red’ grapefruit (Citrus paradisi Macf.). Constant storage at 1° for 28 days resulted in excessive CI; however, conditioning the fruit for 7 days at 10°, 16°, or 21° significantly reduced CI during 21 days of storage at 1°. Conditioning for fewer than 7 days resulted in significantly more CI. Treatment with 40% CO2 during 3 days of conditioning at 21° also reduced CI during low-temperature storage. Conditioning for 7 days at 10°, 16°, or 21° followed by a gradual lowering of the temperature to 1° was also effective. Placing the fruit at 10° for 14 days after 21 days of storage at 1° had no adverse effects; neither did an additional holding period of 7 days at 21°. Decay, mostly green mold rot caused by Penicillium digitatum Sacc., was negligible during storage but increased at 21°. At 21°, decay was sometimes related to the extent of CI during storage.
New Method of Degreening Lemons by a Combined Treatment of Ethylene-releasing Agents and Seal-packaging in High-density Polyethylene Film1
Authors: Ben-Yehoshua S. , Shapiro B. , Kobiler Ilana
Published: August 2022

Conventional degreening of fruits of lemon [Citrus limon (L.) Burm f.] by ethylene gas or treating with the ethylene-releasing agents (2-chloroethyl) phosphonic acid (ethephon) or 2-chloroethyl-tris(2-methoxyethoxy)silane, aggravates the development of various blemishes resulting, at times, in a loss of more than half of the fruit. Seal-packaging of lemons in 10 μm-thick film of high-density polyethylene (HDPE) markedly inhibited the development of blemishes. After 3 weeks’ storage, fruit commercially degreened with ethylene was 19.8 % blemished when unpackaged and 6.3% blemished when sealed in HDPE. Furthermore, this treatment delayed deterioration of fruit for a period longer than 6 months, much beyond that required for marketing. Spoilage resulting from blemishes, decay, softening, or overripe-coloration was much lower in sealed than in the non-sealed fruit. The combination of treatment with ethylene-releasing agents and HDPE seal-packaging permits degreening of lemons.
Effect of Polyethylene Mulch and Summer Irrigation Regimes on Subsequent Flowering and Fruiting of ‘Olympus’ Strawberry1
Authors: Renquist A. Richard , Breen Patrick J. , Martin Lloyd W.
Published: August 2022

Strawberries [Fragaria × ananassa Duch. cv. Olympus] were planted in 2 successive years and grown at 3 levels of drip irrigation, with and without polyethylene mulch. Differential irrigation was applied only during 1 (1977) or 2 (1978) months during the summer and all treatments were irrigated equally during the following spring. In both summers, the soil water potential at 20-cm depth was maintained above −0.5 bars for the highest level of irrigation and fell below −11 bars at the low level. Mulch conserved soil moisture at the 2 lower irrigation levels in 1977, but this effect was nearly absent in 1978 conditions. The highest irrigation regime had about 22% more flowers and 18% more fruit than the lowest regime in the spring of the first harvest season in both plantings. Mulch only increased flowering in the 1977 planting (12%), whereas the number of fruit was increased about 11% by mulch in both plantings. The high yield capacity of ‘Olympus’ was confirmed (37.8 MT/ha). Mulch increased the yield of the 1978 planting 18%, despite its lack of effect on the number of flowers in that year. This suggests a spring influence on yield. The highest irrigation regime out-yielded the lowest regime by 13% in the first crop of both plantings, although this increase was significant only in the 1977 planting. The second year crop of the 1977 planting yielded 21% less than the first year, and failed to show significant treatment differences in flower number or fruit yield despite much larger plant size with mulch and higher irrigation levels. The yield component which showed the greatest decline between years was the percentage fruit set. In general, mulch and greater summer irrigation increased fruit yield less dramatically than they enhanced vegetative growth. However, the 13% to 18% increases may represent a significant economic gain because the typical yield of ‘Olympus’ is much higher than other Pacific Northwest cultivars. Mulch also produced a greater water use efficiency.
Foraging Behavior of Honey Bees on ‘Golden Delicious’ and ‘Delicious’ Apple1
Authors: Kuhn Eric D. , Ambrose John T.
Published: August 2022

“Sideworking,” a foraging behavior of honey bees (Apis mellifera L.) which does not result in pollination, previously has been reported to occur on blossoms of ‘Delicious’ cultivar (Malus domestica Borkh.). “Sideworking” is also apparent on the blossoms of ‘Golden Delicious’ cultivar. The structure of a ‘Golden Delicious’ blossom, a commonly used pollinizer of ‘Delicious’ cultivar, permits honey bees to forage for nectar by standing on the petals of the blossom while forcing their proboscises through the stamens. As a result, the honey bees usually do not contact the blossom’s anthers and pollen transfer is unlikely. In an orchard of ‘Golden Delicious’ and ‘Delicious’ cultivars where ‘Delicious’ bloomed slightly ahead of ‘Golden Delicious’, the percentage of honey bees working from the side on the blossoms of ‘Golden Delicious’ was initially high but dropped as the bloom of ‘Golden Delicious’ advanced. A preponderance of sideworking honey bees on the pollinizer ‘Golden Delicious’ during the period in which the blossoms of ‘Delicious’ optimally set fruit might have a negative effect on fruit shape and/or fruit set of ‘Delicious’ apples.
Influence of Foliarly Applied Growth Regulators on Sex Expression in Watermelon1
Authors: Christopher David A. , Loy J. Brent
Published: August 2022

The growth regulators abscisic acid (ABA), 6-benzylamino purine (BA), (2-chloroethyl)phosphonic acid (ethephon), aminoethoxyvinylglycine (AVG), and silver nitrate were applied in weekly or biweekly foliar sprays to watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] plants grown in a greenhouse. Both 10−3 mBA and 10−4 m ABA inhibited stem elongation, but had no effect on flowering patterns. Ethephon at 60 ppm and above prevented flower development, and at 15 and 30 ppm inhibited pistillate flowering and increased staminate/pistillate (S/P) flower ratios fivefold to sevenfold. Grafting watermelon scions to rootstocks of gynomonoecious and andromonoecious muskmelon did not affect sex expression or the response of watermelon to ethephon. AVG at 100 and 200 ppm and 500 ppm AgNO3 reduced the number of staminate flowers and promoted hermaphroditic flowering. In watermelon, contrary to other cucurbits, applied ethylene appears to suppress rather than promote ovary development during flower bud differentiation.
Light Intensity and Temperature Effects on Epicuticular Wax Morphology and Internal Cuticle Ultrastructure of Carnation and Brussels Sprouts Leaf Cuticles1
Authors: Reed David W. , Tukey Harold B.
Published: August 2022

At either 440 or 145 μEm−2s−1, greater amounts of cuticle, cutin matrix, and wax were formed at 15° than 25°C on leaves of Brussels sprouts (Brassica oleraceae. L., Gemmifera group), but the reverse occurred on leaves of carnation (Dianthus caryophyllus L.). At either 15 or 25°, greater amounts of cuticle, cutin matrix, and wax were formed at 440 than 145 μEm−2s−1 on both species. For Brussels sprouts, at 25°/440 μEm−2s−1 and 25°/145 μEm−2s−1, large parallel wax dentrites covered the leaf surface. At 15°/440 μEm−2s−1, dentrites were smaller and morphologically less elaborate. At 15°/145 μEm−2s−1, epicuticular wax occurred as scattered rods perpendicular to the leaf surface. Carnation epicuticular waxes consistently occurred as rods, but as temperature and/or light intensity decreased, rod length decreased and density increased. There were no changes in internal cuticle ultrastructure of either species in different environments, but cuticle thickness increased as temperature and light intensity decreased. Epicuticular waxes visualized in surface view by scanning electron microscopy (SEM) were extracted by procedures for transmission electron microscopy (TEM) observation.
Electrolyte Leakage from Daminozide-treated Apples Held in Air, Low-pressure, and Controlled-atmosphere Storage1
Authors: Bérard L. S. , Lougheed E. C.
Published: August 2022

The permeability of the flesh of ‘McIntosh’ apples (Malus domestica Borkh.), as measured by electrolyte leakage, appeared to follow a phasic pattern with aging. A phase of initial reduction of permeability preceded a large increase, then there was a slight transient decrease in permeability, and finally a slight increase. Field treatment with butanedioic acid mono (2,2-dimethylhydrazide) (daminozide), early harvest, controlled atmosphere and low-pressure storage as well as a low storage temperature (0.5 vs. 3.5°C) favored a reduction of permeability. The effect of low-pressure storage on the reduction of permeability appeared to be due to a delay of ripening as evident in delayed C2H4 production; that of controlled-atmosphere storage seemed to be due to some effect of the atmosphere other than one upon ripening, because the fruit produced C2H4 upon removal from storage.
Response of Squash to Irrigation, Nitrogen Fertilization, and Tillage Systems1,2
Authors: Smittle D. A. , Threadgill E. D.
Published: August 2022

‘Dixie’ squash (Cucurbita pepo L. var. condensa) were subjected to factorial combinations of 2 irrigation levels, 4 N treatments, and 3 tillage methods on a Lakeland sand soil during 1978, 1979, and 1980. The greatest marketable fruit yield resulted from a combination of applying irrigation at 0.3 bar soil water tension, applying 22.5 kg N/ha through the irrigation system at 2, 3, 4, 5, and 6 weeks after planting, and preparing the seedbed by moldboard plow tillage. Yields were reduced 3 to 16% by either reducing the N rate, allowing a greater soil water tension before irrigating, or by the use of subsoil-bed or disk-harrow tillage system. A combination of subsoil-bed tillage and application of irrigation at 0.6 bar soil water tension resulted in the greatest yield when squash received a single N application after planting.
Juice Characteristics and Internal Atmosphere of Waxed ‘Smooth Cayenne’ Pineapple Fruit1
Authors: Pauli Robert E. , Rohrbach Kenneth G.
Published: August 2022

Waxing fruit of fresh pineapple [Ananas comosus (L.) Merr.] with a polyethylene-paraffin mixture influenced a number of juice characteristics as well as internal fruit atmosphere composition. Juice pH declined less and total acidity increased less with increased storage at 8°C when fruit were waxed. Total soluble solids decreased from 16° to 15° Brix with 4 weeks storage at 8° with waxing having no effect. During the 3rd week at 8°, total ascorbic acid levels decreased from an initial value of 65 mg/liter juice to less than 5mg/liter in unwaxed fruit, and to 35 mg/liter in fruit waxed with 20% v/v wax-water. Increasing wax concentration increased the retention of juice ascorbic acid. Absorbance at 267 nm in unchilled fruit was related to shell color. Juice absorbance at 267 nm decreased with storage time, with a greater decline in more mature fruit, without effect from varying wax pH or percent polyethylene. The internal fruit gas atmosphere varied with coating concentration. Increasing the length of storage time to 4 weeks at 8° increased the size of respiration peak obtained when the fruit was removed to non-chilling temperatures (22°). Unwaxed fruit at 8° had less than 1% CO2 in the fruitlet locule, while waxed fruit contained 2 to 3% CO2. Upon transfer of fruit from 8° to 22°, internal CO2 increased to near 10% in unwaxed fruit and to 15 to 20% in waxed fruit.
Investigation of Anthocyanic Pigments and Substances Inhibitory to Seed Germination in the Fruit Pulp of Liriope muscari1
Authors: Hruska Ann Fagan , Dirr Michael A. , Pokorny F. A.
Published: August 2022

Fruit pulp extracts of Liriope muscari (Decne.) Bailey were analyzed chromatographically and spectrophotometrically to determine which compounds were responsible for their blue-black color. A trihydroxy series of mon-oglycosylated anthocyanidins (delphinidin, petunidin, malvidin) were isolated. The malvidin glycoside appeared to be involved in a co-pigment complex with at least a flavone, explaining the neutral pH-stable blue color. Previous work indicated that a water-soluble seed germination inhibitor was present in the pulp. Nine bands were collected as fractions from Sephadex column chromatography. Each fraction was monitored by paper chromatography before use in a bioassay that tested for germination inhibitors. Several fractions significantly inhibited seed germination of Cucumis sativus L. ‘Poinsett’. Four classes of phenolic compounds were identified from the chromatograms: anthocyanins, anthoxanthins, phenolic acids, and a tannin-like polyphenol. Phenolic acids and the tannin-like substance were most prevalent in the 3 most toxic fractions. A mixture of these 3 fractions caused seed germination inhibition exceeding that attained by the individual fractions. Caffeic acid was tentatively identified as one of the phenolic acids present. Results indicated that germination inhibition is due to the combined action of several phenolic compounds.
Yield, Fruit Size, and Quality of Three Apple Cultivars as Influenced by Summer or Dormant Pruning1
Authors: Marini Richard P. , Barden John A.
Published: August 2022

‘Delicious’, ‘Golden Delicious’, and ‘Stayman’ apple trees (Malus domestica Borkh.) were summer pruned in late June or mid-August. Fruit were smaller on June- or August-pruned ‘Stayman’ trees than on comparable dormant-pruned control trees. Summer pruning had little effect on the size of ‘Delicious’ and ‘Golden Delicious’ fruit. Soluble solids were suppressed within 2 weeks after summer pruning on all cultivars, but fruit firmness was unaffected. Summer pruning slowed the rate of starch disappearance from fruit flesh. Preharvest drop, severity of watercore, and bitter bit were suppressed by summer pruning. Calcium concentration of fruit flesh was not significantly increased by summer pruning. Yield, expressed as total fruit weight or number of fruit per tree, was not consistently influenced by summer pruning over a 2-year period.
Nitrogen Status Evaluation of Tomato Plants1
Authors: Mason S. C. , Wilcox G. E.
Published: August 2022

Recently matured whole leaves of tomato Lycopersicon esculentum Mill cvs. Centennial and Knox) gave the most reliable indication of total N, while NO3-N in older mature leaf petioles better reflected N availability and absorption. The NO3-N content of petioles was more indicative of N status of the plant than total N analysis of whole leaves. The NO3-N and total N contents of leaf parts generally decreased with increasing maturity. Soil solution NO3-N concentration increased exponentially with increasing N application rates. The first 45 kg N/ha increments increased soil solution NO3-N concentration only 10 ppm whereas the fourth 45 kg N/ha increment increased NO3-N concentration 40 ppm. Ninety kg N/ha application produced a concentration of 48 ppm NO3-N that resulted in a nearly maximum petiole concentration of 14,500 ppm NO3-N, indicating that this NO3-N concentration provided sufficient available N for the immediate reserve requirements for plant growth.
Responses of Malus Clones to Programmed Low-temperature Stresses in Late Winter1
Authors: Holubowicz Tadeusz , Cummins J. N. , Forsline P. L.
Published: August 2022

The cold resistances of 14 Malus clones were determined in early March annually from 1974 to 1978. Dormant twigs were cooled at −1.8°C/hr, samples removed at 5° steps from −15 to −45°, and thawed gradually. After thawing, impedance measurements were made and the twigs were held for 16 days under intermittent mist to determine recovery. Rankings of data on growth of twigs held under intermittent mist for 16 days after thawing were similar but not identical to direct impedance values obtained immediately after thawing. Tissue damage had no evident relation to shoot diameters. Surfically discernible root germs, which were present on Mailing 7 (M 7), M 26, M 27, Malling-Merton 106 (MM 106), and Cornell-Geneva 10 (CG.10), were killed at or above −15°. ‘Empire’ and Ottawa 4 were least sensitive and ‘Katherine’ and ‘Jonagold’ most sensitive to low temperatures. The responses of M 26 to low temperatures varied widely from year to year. We could discern no relationship between hardiness in late winter and timing of spring budbreak. The growth response method reported here appears to be closely related to whole plant response under field conditions.
Effects of Cultivar, Irrigation, and Ethephon on the Yield, Harvest Distribution, and Quality of Machine-harvested Blackberries1
Authors: Sims C. A. , Morris J. R.
Published: August 2022

(2-Chloroethyl)phosphonic acid (ethephon) was sprayed on irrigated and non-irrigated erect (‘Cherokee’ and ‘Comanche’) blackberries (Rubus, subgenus Eubatus) before the first harvest and after the second harvest at 1000 and 1500 ppm. ‘Cherokee’ had higher and more concentrated yields and better color than ‘Comanche’. Dripirrigation increased yield and berry weight, but reduced both raw and processed fruit color. Ethephon applied before the first harvest or after the second harvest increased the amount of early fruit harvested. Ethephon reduced berry weight, percent soluble solids, titratable acidity, and increased the pH, and raw and processed product color.
Leaf Elemental Content Comparisons of Own-rooted Peach Cultivars to the Same Cultivars on Several Peach Seedling Rootstocks1
Authors: Couvillon Gary A.
Published: August 2022

Leaves from several own-rooted peach cultivars [Prunus persica (L.) Batsch] were found to contain higher Ca and Mg concentrations than leaves of the same cultivars budded to several peach seedling rootstocks. Own-rooted ‘Loring’ cuttings had a higher leaf N content than ‘Loring’ on ‘Nemaguard’; and in 1 year out of 2, own-rooted ‘Redhaven’ trees had higher leaf N concentrations than ‘Redhaven’ on ‘Bailey’ rootstocks.
Effect of Mineral Nutrient Sprays on Photosynthesis and Stomatal Opening of Water-stressed and Unstressed Apple Seedlings II. Potassium Sulfate Sprays1
Authors: Swietlik Dariusz , Korcak R. F. , Faust Miklos
Published: August 2022

‘York Imperial’ apple seedlings (Malus domestica Borkh.) grown in nutrient solution cultures with decreased water potential to− 1.0 bar by polyethylene glycol (PEG) increased water consumption, photosynthesis rate (Pn), and stomatal conductance (Cs). High light preconditioning of the plants used in this experiment was probably the reason why− 1.0 bar water potential in the nutrient solution was not low enough to induce apple seedling responses typical of water-stressed plants. However, application of PEG stress (−1.0 bar), to K-sprayed (K2SO4, −0.5%) trees lowered seedling water consumption Pn, and Cs. Potassium sprays alone did not significantly affect water consumption, Pn or Cs. When the water potential of the nutrient solution of PEG stressed plants was further decreased to −2.5 bars, unsprayed trees started to wilt within 2 days while sprayed trees did not. It is proposed that earlier stomatal closure of K-sprayed trees when stressed, already at low level of water stress (−1.0 bar), prevented plant water depletion when stress level was increased. This in turn delayed commencement of plant wilting. Potassium sprays also increased root:shoot ratio and root K concentration in PEG-stressed plants. These responses of K-sprayed trees could also contribute to greater tolerance to higher levels of water stress.
Freezing Resistance of Ornamental Trees and Shrubs
Authors: Sakai A.
Published: August 2022

Freezing resistance of winter twigs from about 300 tree species and cultivars native to different climates in the world was assessed. Dormant 1-year-old twigs collected from mature trees were artificially hardened. Almost all of the trees, which ranged from tropical to subtropical in both Asia and America, sustained freezing injury to some of their tissues at temperatures below −5°C. Evergreen and deciduous broad-leaved trees native to warm-temperate climates survived freezing at −7° to −20°. In general, flower buds were far less resistant than vegetative buds. Winter minimum temperature is among the important factors governing the northern limits of cultivated plants.
Influence of Growth Regulators on Ionic Thiocyanate Content of Cruciferous Vegetable Crops1
Authors: Chong Calvin , Kanakis A. G. , Bible Bernard B.
Published: August 2022

Under greenhouse conditions, butanedioic acid mono-(2, 2-dimethylhydrazide) (daminozide) at concentrations of 100, 500, or 1000 mg/liter applied to ‘Burpee white’ radish (Raphanus sativus L.) and 500 or 100 mg/liter applied to ‘Snow Ball’ turnip (Brassica rapa L.), significantly increased root thiocyanate content. Concentrations of 1000 mg/liter gibberellic acid (GA), 500 mg/liter 6-benzylamino purine (BA), and 10 mg/liter 2,4-dichlorophenoxyacetic acid (2,4-D) also increased root thiocyanate content of both species. Under field conditions, applications of 1000 mg/liter daminozide, 1000 mg/liter GA, and 500 mg/liter BA increased root thiocyanate in ‘Burpee White’ radish, ‘Tokyo Cross’ turnip, and ‘Snow Ball’ turnip grown on both loam and organic soil. While there was no effect of these growth regulators on thiocyanate content in roots of ‘White Icicle’ radish, heads of ‘Early Green Ball’ cabbage (B. oleracea L., Capitata group), or ‘Green Mountain’ broccoli (B. oleracea L., Italica group), results for head thiocyanate content of ‘Waltham 29’ broccoli were inconsistent. Five of the seven crops grown on organic soil had thiocyanate contents that were higher than those grown on loam soil.
Control of Orchard Voles with Broadcast Baits1
Authors: Byers R. E. , Merson M. H. , Palmateer S. D.
Published: August 2022

Excellent control of pine voles (Microtus pinetorum) and meadow voles (M. pennsylvanicus) was achieved using several commercially formulated, pelletized anticoagulant baits as a single broadcast treatment. A new pelletized formulation of zinc phosphide (Zn3P2) was shown to kill about 30% more voles in both hand-placed and broadcast field trials when compared to one of the commercially available, surface-coated 2% Zn3P2corn and oat formulations. Hand-placed cellophane- or plastic-packaged rodenticides were shown to be effective. Packs hand-placed under 2 types of covers (cinder blocks or split tires) gave equivalent control. Since about 5% of the hand-placed packs were not opened where voles were known to be present, a low but residual population was sufficient for repopulation of the orchard.
A Compressed Air Test for Carpel Adhesion in Pickling Cucumbers1
Authors: Wehner Todd C. , Saltveit Mikal E.
Published: August 2022

Compressed air was injected into fruit of pickling cucumber (Cucumis sativus L.) to simulate the build-up of gas during brining. Four size grades were tested from 4 cultivars over 2 harvests and 2 seasons. Carpel adhesion, as measured by the air pressure required to separate the carpels, was negatively correlated with fruit size. Higher air pressure was required to separate the carpels of cultivars resistant to balloon bloating. The formation of balloon bloaters in cucumbers brined in commercial tanks was correlated with results from the compressed air test of carpel adhesion, especially with fruit 45 to 51 mm in diameter.
Factors Affecting Survival of Kentucky Bluegrass Sod under Simulated Shipping Conditions1
Authors: King J. W. , Beard J. B. , Rieke P. E.
Published: August 2022

High temperatures during simulated shipping were more consistently injurious to ‘Merion’ Kentucky bluegrass (Poa pratensis L.) sod than other factors tested. Sod produced with increasing amounts of nitrogen had increased rates of temperature rise. Higher nitrogen levels also increased respiration, percent leaf kill, and ethylene production. There was no consistent effect of 6-benzylamino purine (BA) on sod storage life. Mowing to 2 cm prior to harvest reduced the amount of living tissue, causing lower temperatures, lower respiration rates, and less sod injury. Root production after sod transplanting was greatest from sod grown with 0 and 100 kg/ha of nitrogen fertilization and decreased with higher nitrogen rates.
Inheritance of Resistance to Rhizoctonia solani Kuhn in Snap Beans (Phaseolus vulgaris L.)1
Authors: Silva George H. , Hartmann Richard W.
Published: August 2022

F3 progeny tests were used to confirm individual F2 plant Rhizoctonia resistance classifications determined from greenhouse inoculations of bean seedlings. F2 segregations within individual disease classes mostly agreed with the hypothesis that genetic control of resistance to Rhizoctonia is controlled by 3 pairs of genes acting equally and additively. Partially resistant families postulated to be homozygous for 2 pairs of genes for resistance were recovered in the segregating generations in the frequencies expected.
Influence of Agar Concentration on in Vitro Shoot Proliferation of Malus sp. ‘Almey’ and Pyrus communis ‘Seckel’1
Authors: Singha Suman
Published: August 2022

Shoot tips of ‘Almey’ crabapple [Malus baccata (L.) Borkh. × M. pumila var. niedzwetzkyana (Dieck) Schneid.] and ‘Secke!’ pear (Pyrus communis L.) were cultured on Murashige and Skoog medium supplemented with 2 mg/liter 6-benzylamino purine and agar levels ranging from 0 to 1.2%. The greatest shoot proliferation and shoot growth in ‘Almey’ occurred on medium containing 0.3% agar. Higher agar concentrations decreased both shoot proliferation and shoot growth. Increasing agar concentrations resulted in decreased shoot growth in ‘Seckel’, but shoot proliferation was significantly greater at concentrations of 0.6% and higher as compared to 0.3% or lower. Autoclaving caused an acidification of the medium. The addition of agar reduced media acidification. This pH variation does not explain the effect of agar on shoot proliferation and growth.
Genetic Analysis of Two Perfect-flowered Mutants in Cucumber1
Authors: Iezzoni A. F. , Peterson C. E. , Tolla G. E.
Published: August 2022

The M/m locus in cucumber (Cucumis sativus L.) controls the development of pistillate (M/m) vs. perfect (m/m) flowers. However, the F1 between 2 perfect-flowered lines, one derived from ‘Crystal Apple’ and the other derived from a Polish breeding line, had pistillate flowers suggesting the presence of another locus, M-2, acting in a complementary manner. In F2, BC, F3, and F2BC populations, bacterial wilt resistance was used as a linked genetic marker to distinguish between the m/m plants which were resistant to bacterial wilt and the m-2/m-2 plants which were susceptible to bacterial wilt. Analysis of segregating generations confirmed complementary gene action between 2 very closely linked genes, M/m and M-2/m-2, both of which are tightly linked to the gene for bacterial wilt resistance.
The Effect of Chemical Treatments and Heat on Color Stability of Frozen Machine-harvested Strawberries for Jam1
Authors: Sistrunk W. A. , Morris J. R. , Kozup J.
Published: August 2022

A study was conducted on 2 cultivars of mechanically harvested strawberries (Fragaria × ananassa Duch.) to determine the effects of chemical treatments and heat on stability of color in frozen fruit for jam. Treatment with NaHSO3, citric acid or SnCl2 improved color of the jam when compared to the control, as demonstrated by Color Difference Meter (CDM) values and sensory ratings. The CDM color functions were higher on jam made from frozen puree than from frozen whole fruit, yet panel scores were significantly higher on jam from whole fruit. The jam made from frozen puree browned more during storage than that made from whole fruit. There were significant differences in color between cultivars and storage temperatures, but differences among treatments were larger. Treatment with NaHSO3, citric acid or SnCl2 offer possibilities for stabilizing color in jam.
Differentiation of Malus Clones into Resistance Classes by their Effects on the Biology of Eriosoma lanigerum Hausmn.1
Authors: Mackenzie J. D. , Cummins J. N.
Published: August 2022

Degrees of resistance of 4 Malus clones to woolly apple aphid (WAA) were determined by the survival, development and behavior of nymphs caged on the plants. Nymphal survival rates after 2 weeks on ‘Empire’, ‘Northern Spy’, and ‘Robusta 5’ were 78%, 30%, and 0.8% respectively. After 4 weeks, only the aphids on ‘Empire’ were at reproductive age. M. baccata mandshurica (Maxim.) Schneid. PI 322713 ‘Manchurian Crab’ expressed partial resistance compared to ‘Empire’ on the basis of insect developmental times, even though insect survival after 2 weeks was unaffected. First instar developmental times on ‘Manchurian Crab’ and ‘Empire’ were 14 and 5 days respectively; days to reproductive maturity was greater than 30 days for ‘Manchurian Crab’ compared to 13 for ‘Empire’. Different feeding behavior was expressed by the proportion of aphids in motion at the times of observation and proportion of aphids feeding at the same location for 12-hr periods. The data suggest that for comparing quantitative differences in resistances of clones, determining developmental times is a more sensitive technique than measuring nymphal survival.
Effect of Soil Acidity and Nitrogen on Yield and Elemental Concentration of Bush Bean, Carrot, and Lettuce1
Authors: Hemphill Delbert D. , Jackson Thomas L.
Published: August 2022

Bush beans (Phaseolus vulgaris L.), carrots (Daucus carota L.), and lettuce (Lactuca sativa L.) were grown for 3 years on soils amended with S or lime and N fertilizer. Yields of all crops increased with lime application but response to N varied among crops and years. Lettuce head weight tended to increase with N application at pH greater than 6.0, but it decreased with N application at lower pH levels. A soil pH of 5.6 to 6.4 was optimal for carrots and beans, and of 6.1 to 6.6 for lettuce. Plant tissue K and Mg concentrations were not affected by soil pH or N rate. Phosphorus and Ca concentration of plant tissue generally increased with lime application. Plant tissue Zn and Mn concentration usually decreased with increasing soil pH between pH 5.1 and 6.4. The reduction in bean and lettuce leaf Mn concentration between pH 5.1 and 5.7 ranged from 30 to 71%. Low bean yields at pH 5.1 were possibly caused by a combination of Mn toxicity and P deficiency. Failure of lettuce to head at low pH may have been caused by Mn toxicity.
Identification of Flavonoid Chemical Markers in Roses and their High Pressure Liquid Chromatographic Resolution and Quantitation for Cultivar Identification1
Authors: Asen S.
Published: August 2022

Flavonoids in flowers of ‘White Masterpiece’, ‘Bridal Pink’, and ‘Samantha’ roses (Rosa spp) were either kaempferol or quercetin 3-glycosides. They were the glucoside, xyloside, arabinoside, rhamnoside, glucuronide, rutinoside, a rhamnosylglucoside (not rutinose or neohesperidose), an acylated form of the rhamnosylglucoside, and galloylghicoside. Kaempferol 4’-glucoside, an important marker derived almost exclusively from old Scotch roses (R. foetida and R. spinossisima) was present only in ‘White Masterpiece’. Anthocyanins from ‘Bridal Pink’ and ‘Samantha’ were either cyanidin or pelargonidin 3,5-diglucosides along with traces of the related 3-glucoside. Parameters for the resolution and the quantitation of these flavanoids, by high pressure liquid chromatography, were established. Uniform sampling techniques were developed because of the quantitative differences in the flavonoid distribution in a rose petal. Changes in the rate of fertilizer application and daylength affected only the concentration of the flavonoids, and the ratio of each compound to the total remained fairly constant.
Ultrastructural Localization of Polysaccharides in Apple Leaf Cuticles1,2
Authors: Reed David W. , Tukey Harold B.
Published: August 2022

The ultrastructural localization of polysaccarides in Malus domestica Borkh. leaf cuticles was investigated by electron microscopy staining. The cuticle/cell wall interface was not stained by ruthenium red or hydroxylamine-ferric chloride, indicating the lack of a distinct pectin layer. The inner region of the cuticle was intensely and uniformly stained by phosphotungstic acid (PTA) and was lightly stained by silver proteinate, indicating the presence of polysaccharides, which in part may be pectin as indicated by staining with ruthenium red. Fibrils in the inner region of the cuticle were not stained by ruthenium red, hydroxylamine-ferric chloride or silver proteinate, but appeared lightly stained by PTA; this suggests by deduction that the fibrils may consist of cutinized cellulose. The outer region of the cuticle was not stained by any of the staining procedures, indicating the lack of polysaccharides.
New Anthocyanins from Tibouchina granulosa1
Authors: Francis F. J. , Draetta I. , Baldini V. , Iaderoza M.
Published: August 2022

Two previously unreported nuyor pigments were found in the blue flowers of Tibouchina granulosa Cogn.: malvidin-3-(di-p-coumaroyl xyloside)-5-glucoside and malvidin-3-(p-coumaroyl xyloside)-5-glucoside. The first pigment is easily degraded to the second since the second p-coumaric acid molecule is quite labile. Two other pigments were present in trace amounts.
Cytoplasmic Male Sterility in Common Bean1
Authors: Bassett M. J. , Shuh D. M.
Published: August 2022

The inheritance of male sterility was studied in germplasm of common bean (Phaseolus vulgaris L.) obtained from the Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia. The source was selected for plants with high pollen abortion rates (mean = 91%) and for failure to set any seed or pods by self-pollination when grown in screened greenhouses. These male-sterile plants were crossed with the snap bean ‘Sprite’, and the resulting F1 progenies were all male-sterile under greenhouse conditions. The F1 plants were backcrossed to ‘Sprite’ and the BC1 progenies did not segregate for male-fertile plants under field conditions. Four more backcrosses to ‘Sprite’ have produced progenies that were uniformly male-sterile. It was concluded that the CIAT source of male sterility is inherited through the maternal parent and is cytoplasmic. Nineteen commercial cultivars of snap beans and dry beans were crossed onto BC3 plants, and none of these genotypes restored the pollen fertility in F1 progeny.
Ethylene, Fungi, and Summer Fruit Drop of Navel Orange1
Authors: Southwick Stephen M. , Davies Frederick S. , El-Gholl N. E. , Schoulties C. L.
Published: August 2022

Species of Alternaria and Gloeosporium were most often isolated from fruit with blossom-end yellowing (BEY), a disorder associated with summer fruit drop of navel orange [Citrus sinensis (L.) Osbeck]. Fruit inoculated with pure cultures of these fungi did not develop BEY; however, wounded fruit which were inoculated with fungi produced higher levels of ethylene and more extensive BEY than wounded, noninoculated fruit. Fruit with BEY produced higher amounts of ethylene than symptomless fruit. The methoxy analog of rhizobitoxine (methoxyvinylglycine) did not reduce ethylene levels, and silver nitrate increased ethylene production from fruit with BEY. Ethylene and fungi are associated with BEY of navel orange but do not appear to be causal factors.
Differences in Biochemical Composition between ‘Beurre d’Anjou’ and ‘Bose’ Pears during Fruit Development and Storage1
Authors: Chen P. M. , Richardson D. G. , Mellenthin W. M.
Published: August 2022

A comparative study in 1979 and 1980 between ‘Anjou’, a long-keeping winter pear and ‘Bose’, a shorter keeping winter pear (both Pyrus communis L.) revealed that ethanol-insoluble matter, titratable acids, soluble solids, proteins, and free amino acids in fruit of both cultivars during fruit development, maturation, and storage period fluctuated from season to season and were not associated with their difference in postharvest life. Malic acid was the major fraction of organic acids in both cultivars, and it declined at a faster rate in ‘Bosc’ than in ‘Anjou’ during storage at −1.1°C. The amounts of citric, oxaloacetic, and fumaric acids were higher in ‘Bosc’ than in ‘Anjou’ and were maintained at constant levels throughout the storage period. Internal ethylene in both cultivars early in fruit development was about 0.3 ppm and decreased rapidly to below 0.07 ppm during late fruit development and harvest period. For 2 seasons, ‘Bosc’ was capable of ripening after less than 20 days of chilling at −1.1°C when its internal ethylene increased to 0.2 ppm, while ‘Anjou’ required at least 50 days of chilling to develop the ripening capacity coincident with an internal ethylene above 2.0 ppm. Internal ethylene accumulated in ‘Bosc’ about 8 times faster than in ‘Anjou’ during the first 60 days of storage at −1.1° and reached an equilibrium at 40 ppm for ‘Bosc’ and only 5 ppm for ‘Anjou’ during the remaining storage period. After any corresponding period of cold storage, both ethylene and CO2 productions of ‘Bosc’ at ripening temperature of 20° were higher than those of ‘Anjou’, and ‘Bosc’ also required fewer days to reach the climacteric peaks than did ‘Anjou’.
Early Season Root and Shoot Growth of ‘Golden Delicious’ Apple on Four Rootstocks as Affected by Pruning at Planting1
Authors: Young Eric , Werner Dennis J.
Published: August 2022

Apple trees (Malus domestica Borkh. cv. Smoothee Golden Delicious) on 4 rootstocks Mailing (M) 9, Malling-Merton 106/M 9, MM 106, and seedling, received 4 pruning treatments at planting: no pruning, shoot pruned to 70 cm above graft union and branches removed, root pruned to 1/3 its original volume, or shoot and root both pruned as above, to determine effects on early shoot and root growth. Shoot pruning stimulated rapid new shoot growth and resulted in the highest new shoot relative growth rate and new shoot/total shoot dry weight ratio. Also, shoot pruning, with and without root pruning, resulted in very little root dry weight increase up to 8 weeks after planting, indicating a competitive inhibition of root growth by rapid new shoot growth. Root pruning, with and without shoot pruning, stimulated the greatest amount of new, white root formation soon after planting, but these contributed very little to root dry weight. Shoot- and root-pruned trees had the lowest shoot and root dry weights with all rootstocks. Pruning treatments significantly altered the root/shoot ratios of trees on M 9 and MM 106/M 9, but not on MM 106 and seedling. Shoot pruning of trees on M 9 caused the greatest deviation of root/shoot ratio from unpruned, heavily favoring shoot growth.
Quality of Muscadine Grapes after Storage with Sulfur Dioxide Generators1
Authors: Ballinger W. E. , Nesbitt W. B.
Published: August 2022

Nine cultivars/selections of muscadine grapes (Vitis rotundifolia Michx.) were stored for 49 days at O°C in 6 liter telescoping, corrugated-cardboard shipping containers with polyethylene liners, and 3 types of commercially available SO2 generators. Susceptibility to decay during storage varied greatly among selections (7 to 82% decay without SO2). The SO2 generators produced up to 29 ppm SO2 and all 3 types reduced decay. The genotypes also varied widely in their tolerance of SO2. Placement of newspaper in the shipping containers reduced the concentrations of SO2, reduced SO2 damage to the fruit by up to 74%, and had an inconsistent influence on the development of decay. Fruit of selection NC 67A015-17 appeared to be the best suited for long-term storage.
Effects of Ethephon on Olive Ripening1
Authors: Rugini E. , Bongi G. , Fontanazza G.
Published: August 2022

Solutions of (2-chloroethyl) phosphonic acid (ethephon) at 1000, 1500, and 2000 ppm were sprayed on trees of ‘Giarraffa’ olive (Olea europaea L.) time midway between the onset of pit hardening, and the maximum respiratory rate induced early pigmentation of drupes. Treatment modified anthocyanins, respiratory ratio (CO2/O2), polyphenols, redox potential, total sugars and their composition, linoleic/palmitoleic acid ratio, and dry weight. Pulp/stone ratio, respiratory rate, pH, uronic acids, oil, principal fatty acids, and protein content did not differ from the control. Ethephon applied after the occurrence of the maximum respiratory ratio only reduced the fruit detachment strength. These results confirm the hypothesis which attributes a climacteric model to the attached fruits and a nonclimacteric model to the detached ones. The physiological modifications of fruits ripened with ethephon were similar to those found in the last stage of natural maturation.
Effect of Ozone Injury and Light Stress on Response of Tomato to Infection by the Vesicular-arbuscular Mycorrhizal Fungus, Glomus fasciculatus1
Authors: McCool P. M. , Menge J. A. , Taylor O. C.
Published: August 2022

Tomato seedlings (Lycopersicon esculentum Mill. ‘Heinz 1350’) were inoculated with the vesicular-arbuscular mycorrhizal fungus Glomus fasciculatus (Thaxter) Gerd. & Trappe and either exposed to 30 pphm (589 μg/m3) ozone or to filtered air for 3 hours once weekly, beginning 3 weeks after inoculation, under long photoperiods (12–13.5 hr). Root infection by G. fasciculatus in ozone-exposed plants was retarded from week 3 to 5 compared to controls but recovered by week 7. Growth rates of mycorrhizal control plants were significantly greater than ozone-exposed mycorrhizal plants, but there were no differences in growth rates of nonmycorrhizal controls, mycorrhizal ozone-exposed plants, and nonmycorrhizal ozone-exposed plants. Under short photoperiods (less than 12 hr), growth rates of mycorrhizal controls were less than nonmycorrhizal controls and ozone did not significantly affect growth rates of nonmycorrhizal plants relative to controls. Leaf chlorophyll levels were similar whether plants were mycorrhizal, nonmycorrhizal, or exposed to ozone.
Induction of Semisterility Mutations in Common Bean, Phaseolus vulgaris L.1
Authors: Bassett M. J. , Hung L.
Published: August 2022

Bean pollen treated with 2, 4, 8, and 16 kR of gamma irradiation was used to produce M1 seed. The M1 plants were screened for semisterility of the pollen. The inheritance of the semisterility mutations was studied in crosses to a tester stock with recessive marker genes and in M2 and M3 progeny tests. The 4, 8, and 16 kR treatments produced nearly 100% lethal mutations while 2 kR produced 70% lethality. The semisterility factors behaved genetically like dominant alleles in F1 test cross progeny but segregated again for a ratio of 1 semisterile to 1 fertile plant in the F2, indicating that the mutants are probably chromosome aberrations and not genic mutations. They may in fact be chromosome translocation heterozygotes. The semisterility factors produced 40 to 60 % pollen abortion and a significant reduction in seed set per pod. Semisterility factors were found in about 5% of the M1 plants tested.
A Scanning Electron Microscope Study of Pollen of Phoenix (Arecaceae)1
Authors: Tisserat Brent , DeMason Darleen A.
Published: August 2022

Pollen samples of 4 cultivars and clones of Phoenix dactylifera L., 2 clones of P. reclinata Jacq. and one clone each of P. humilis Royle, P. roebelenii O’Brien × P. paludosa Roxb., P. rupicola T. Anderson and P. sylvestris (L.) Roxb. were compared using the scanning electron microscope (SEM). All grains were monosulcate, elliptical, and had tectate-perforate exines. Cultivars could be distinguished by differences in pollen morphology and exine structure. Characters that showed morphological variation included presence or absence of wax-like substances, grain length, grain width, and grain length:width ratio. Diverse structural characteristics included shape, pattern, size, and frequency of tectal perforations. Morphological and structural characteristics of pollen may serve as an aid in the taxonomic identification of staminate cultivars in Phoenix.
The Relationship of Impedance Ratios and Stem Moisture Content to Vegetative Maturity and Dormancy in Red-osier Dogwood1
Authors: Timmis K. A. , Fuchigami L. H.
Published: August 2022

Electrical impedance ratios and water contents were measured during the development of vegetative maturity and dormancy in a clone of red-osier dogwood Cornus sericea L.) on plants exposed to 16 hour and 12 hour photoperiods in growth chambers to selectively prevent or induce dormancy. Vegetative maturity was designated as the point at which buds were no longer stimulated to grow following artificial defoliation. After this time the ratio of impedance values obtained from the frequencies 10 kHz:100kHz increased and tissue water decreased. Electrical impedance ratios were more easily measured and showed less variation between plants. We conclude that electrical impedance ratios are a means of identifying the onset of vegetative maturity and dormancy in woody deciduous species.