bluuebunny/crossref_metadata_2025 huggingface dataset:
HEMICELLULOSE APPARENT MOLECULAR SIZE CHANGES DURING SOFTENING OF PEACH FRUIT
Authors: Hegde Supreetha , Maness Niels
Published: February 2019

Peach fruit softening appears to be associated with changes in cell wall polymers, particularly pectins and hemicelluloses. To determine changes of cell wall polymers associated with peach fruit softening, we conducted sequential extractions of pectin and hemicellulose from softening fruit. A more tightly bound hemicellulose fraction contained considerable amounts of pectin associated sugars. This fraction was separated into charged and neutral fractions, using anion exchange chromatography, and then fractionated into two apparent molecular weight classes by size exclusion chromatography. Virtually all of the charged fraction eluted in the higher apparent molecular weight fraction. The neutral sugar fraction segregated into both apparent molecular weight size classes, with a redistribution from the large to the small size class during softening. This redistribution was accompanied by changes in neutral sugar composition. A possible relationship between changes in this fraction and fruit softening will be discussed. Supported by USDA grant 92-34150-7190 and the Oklahoma Agricultural Experiment Station.
PREDICTION OF STARCH AND OTHER SOLIDS CONTENT IN SWEETPOTATOES BY VISCOSITY
Authors: Silva Juan L. , Alexis Kednal
Published: February 2019

Models for prediction of starch, alcohol-insoluble solids (AIS) and glucose were developed by measuring the viscosity of freeze-dried sweetpotato [Ipomoea batatas (L.) Lam] flour. Green (processed within 24 h) and cured. Jewel and Beauregard roots-were cooked, peeled, pureed and freeze-dried. Viscosity of the flour was measured with a Brabender Viscoamylograph and a Brookfield Viscosimeter. Total solids, starch, AIS, glucose, fructose and sucrose were quantified. There was a strong correlation (R2=0.99) between Brookfield and Brabender viscosity. Results showed significant correlations between Brookfield apparent viscosity or Brabender viscosity units at the gelatinization stage and starch (R2=0.82 and 0.81), AIS (R2=0.S7 and 0.81), and glucose (R2=0.87 and 0.86) content. Apparent viscosity of flour from green roots increased through gelatinization and upon cooling, but that from cured roots remained constant throughout.
GROWTH REGULATOR EFFECT ON PIGEONPEA (CAJANUS CAJAN) DEVELOPMENT
Authors: Marsh Lurline , Marsh Dyremple , Cooper Brian
Published: February 2019

The influence of benzyladenine (BA) and ethrel on vegetative and reproductive characteristics of 2 pigeonpea genotypes was evaluated in field and greenhouse study. Plants sprayed with benzyladenine or ethrel at 400 or 800 ppm levels at both the vegetative and flowering stages tended to be smaller, had more floral abscissions and produced more pods than those sprayed only at the flowering stage. Increased chemical concentration decreased plant size. Plants treated with BA produced several curved distorted leaflets. None of the applications in the field study significantly improved pod set over the 23% recorded for the controls.
INHERITANCE OF ANTHOCYANIN DEFICIENCY IN DEWBERRY (RUBUS TRIVIALIS)
Authors: Gupton Creighton
Published: February 2019

Anthocyanin deficient dewberry (Rubus trivialis Michx.) clones with translucent ripe fruit and green canes were studied to determine their possible utilization as a source of marker genes for blackberries. Albino dewberries from two locations designated Bonnette (BON and Harriel (H) were crossed with each other and with normal dewberry (DB). F1 plants were testcrossed. DB X H produced 62 plants all of which had red canes. BON X DB produced 59 plants all of which had red canes. BON X H produced nine plants all of which had green canes. The segregation ratio of each testcross supported the hypothesis that anthocyanin deficiency in dewberry is controlled by a single recessive gene. A recessive allelet known to cause a very low concentration of anthocyanin, giving fruit with yellow color and stems with non-pigmented spines, is probably responsible for the mutant trait. Its simple inheritance provides potential for anthocyanin deficiency to be used as a marker gene.
PERENNIAL LEGUME GROUND COVERS INCREASE BENEFICIAL ARTHROPODS AND SUPPLY NITROGEN IN PECAN ORCHARDS
Authors: Shiferaw A. , Smith M.W. , Eikenbary R.D. , Arnold Don C.
Published: February 2019

Perennial legumes ground covers were evaluated in pecan (Carya illinoinensis) orchards to supply nitrogen and increase beneficial arthropods. Ground covers were `Kenland' red clover (Trifolium pratense), `Louisiana S-1' white clover (Trifolium repens), a mixture of these two legumes, or bermuda grass (Cynodon dactylon), each in 5 ha plots. Nitrogen was applied at 0-200 kg·ha-1 N in 50 kg intervals to bermuda grass plots, and was omitted on the legumes. Aphids feeding on the legumes attracted lady beetles; however, lady beetle populations in the tree canopies were not affected by ground cover treatment. The most abundant lady beetle species in legumes were Coleomegilla maculata lengi (77%) and Coccinella septempunctata (13%); whereas, dominant species in tree canopies were Coleomegilla maculata lengi (33%). Olla v-nigrum (20%). Cycloneda munda (18%) and Coccinella septempunctata (15%). Several other beneficial arthropods were sampled in legumes and tree canopies. Aphid populations feeding on pecans were low (peak population ≈ 2 aphids/leaf), and not affected by ground cover treatment. Legumes supplied the equivalent of applying 68-156 kg·ha-1 N.
THE EFECTS OF LEONARDITE ON GROWTH OF TOMATO SEEDLINGS
Authors: Pertuit A.J.
Published: February 2019

Lycopersicon Lycopersicum `Mountain Pride' seedlings were greenhouse grown for 8 weeks in pots of Congaree silt loam amended with 1/8 volume leonardite. They received the recommended rate or half the recommended rate of 5-10-10 granular fertilizer (surface applied) with urea or ammonium sulphate as N sources. Leonardite enhanced plant growth (plant height, fresh and dry weights, stem diameter, and leaf area) only when utilized with a complete fertilizer, regardless of the N source; however, it was more effective with ammonium sulphate than with urea. With ammonium sulphate, the amount of N applied could be halfed if leonardite were added, producing about the same positive results achieved with urea at the full recommended N rate hut without leonardite added.
FOLIAR TOTAL NONSTRUCTURAL CARBOHYDRATES IN APPLE CULTIVAR/ROOTSTOCK COMBINATIONS
Authors: Matta Frank B. , Sloan Crofton , Khan Shakeel
Published: February 2019

Apple leaves from current seasons' growth at mid-season (July) and during dormancy (December) were used to determine the influence of various apple scion/rootstock combination on total non-structural carbohydrates (TNC). `Empire' and `Royal Gala' had higher foliar TNC at mid-season compared to `Ultra Gold' on MM.106. `Empire' had higher foliar TNC on Mark than on MM.111, M.7A and M.26. `Blushing Golden' had higher foliar TNC on MM.111 than on the remaining rootstock% There was no significant interaction between cultivar and rootstock. Foliar TNC During Dormancy: `Blushing Golden' had the highest and lowest foliar TNC on MM.111 and M.7A, respectively. Cultivar differences did not exist with any rootstock. Foliar TNC results of this study indicated that there was a higher foliar TNC percentage in leaves at mid-season compared to leaves during dormancy. Data indicated cultivar influences on foliar TNC only at the mid-season. It seems that cultivar differences in TNC might be due to an increase in TNC formation, which during dormancy was stabilized. Rootstock influenced foliar TNC both at mid-season and during dormancy.
CHINESE CABBAGE PERFORMANCE
Authors: Coffey David L.
Published: February 2019

Results from a three-year cultivar evaluation study indicate that Chinese cabbage production is feasible in Tennessee, but may require special attention to bacterial disease control. Individual head weight and projected yields of both the heading (pe tsai) and the nonheading (pak choy) forms compared well to those reported from areas where it is adapted and widely grown. Additional research is needed to identify appropriate planting dates and slow-bolting cultivars, especially for spring production. The ability to achieve predictable and profitable spring and fall production of this specialty crop is essential for establishing markets and promoting Chinese cabbage as a reliable crop that can be incorporated readily into vegetable production systems.
COMPARISON OF TWO METHODS TO EVALUATE THE RESISTANCE OF HAZELNUT GENOTYPES TO EASTERN FILBERT BLIGHT
Authors: Coyne C.J. , Smith D.C. , Mehlenbacher S.A. , Johnson K.B. , Pinkerton J.N.
Published: February 2019

Resistant cultivars are a promising disease control method for eastern filbert blight, which is devastating hazelnut production in Oregon. In 1990, two studies were begun to evaluate the relative resistance of European hazelnut (Coyhls avellana) genotypes to the causal fungus, Anisogramma anomala. A randomized block design of 40 genotypes was planted using inoculated trees planted in the borders as the disease source. The first- and second-year disease incidence (percent) were compared to the published disease incidence (percent) based on exposing potted trees of 44 genotypes to high doses of inoculum. Disease incidence was significantly correlated between the two studies in 1991 (r =0.41, P = 0.02) and in 1992 (r =0.64, P = 0.001; rs = 0.35, 0.025 < P < 0.050). Three genotypes, however, showed no disease in the field, but they had disease in >70% of the potted tree study. A plot of disease incidence in the field planting indicates that the inoculum was present throughout the blocks.
SHORTENED STOCK PLANT PHOTOPERIOD IMPROVES ROOTING OF ELDARICA PINE STEM CUTTINGS
Authors: Wagner A.M. , Fisher J.T.
Published: February 2019

Dormancy level is an important factor in rooting stem cuttings of conifers. Eldarica pine, a Mediterranean species, is a multiple flushing pine that does not appear to express endodormancy in southern New Mexico. Photoperiod manipulations can alter the dormancy level of some conifer species; however, effects on eldarica pine are unknown. Half-sib stock plants were randomly assigned to one of three photoperiods: natural daylength (>12 hours, control), long-term (7 months) exposure to 9-hour daylength (LTSD), and 2-week exposure to 9-hour daylength (STSD). Of the cuttings from LTSD stock plants, 78% rooted; however, only 67% of the cuttings from the other two treatments rooted. Differences in rooting also were related to shoot type of the cuttings. Cuttings from expanded short shoots without a bud rooted more frequently than cuttings from branch shoots with or without a bud present. Applications of these results are discussed.
EFFICIENT REGENERATION AND TRANSFORMATION PROTOCOLS FOR SAFFLOWER (CARTHAMUS TINCT0RIUS L.)
Authors: Baker Charleen M. , Dyer William E.
Published: February 2019

Our goal was to develop efficient regeneration protocols for safflower that could be used in conjunction with Agrobacterium tumefaciens -mediated transformation to introduce genes conferring economically important traits. Direct regeneration of whole plants has been achieved from cotyledon and hypocotyl explants of 30-day-old `Centennial' and `Montola' seedlings. Explants transformed with Ti plasmids containing NPTII and the β-glucuronidase (GUS) reporter gene produced kanamycin-resistant calli and shoots testing positive for GUS activity. Current work is incorporating the bar gene into appropriate Ti plasmids that will be used to confer glufosinate herbicide resistance to elite safflower cultivars. An esterase gene from Bacillus subtilis will be introduced to confer resistance to Alternaria carthami leaf spot disease.
Increasing Scaffold Branch Angle of Atemoya by Manipulation of the Primary Bud Complex
Authors: Marler Thomas E. , Crane Jonathan H.
Published: February 2019

Lateral branches arising from the primary bud complex on limbs of containerized `Gefner' atemoya (Annona squamosa L. × A. cherimola Mill.) plants were removed to determine the influence of branch regrowth on the crotch angle. Pruning the lateral branches to a stub (cl cm) was more effective in inducing regrowth and increasing branch angle of the regrowth than stripping lateral branches by hand. Following lateral branch removal, regrowth did not develop from every node along a stem axis. In a second study, the angle of branch regrowth from tagged nodes following pruning of lateral branches was determined. The mean crotch angle of the primary lateral branches was 58°. Regrowth from the second and third supernumerary buds within each node produced branches with an average crotch angle of 72° and 88°, respectively. The largest increase in attachment angle following pruning was obtained at nodes with narrow primary lateral branches and at nodes located closest to the base of a major axis. The increase in branch crotch angle was not correlated with the size of the preceding lateral branch at a node. These results indicate that pruning off lateral branches with narrow crotch angles may be performed during training atemoya plants to produce scaffold limbs from supernumerary buds within the same nodes with desirably wide crotch angles.
Light Governs the Germination of Impatiens wallerana Hook. f. Seed
Authors: Carpenter William J. , Ostmark Eric R. , Cornell John A.
Published: February 2019

The role of light on impatiens seed germination and radicle emergence was studied. Seeds having a photodormancy require light for only part of the germination period. Germination ≥85% was achieved after 3, 2, or 1 day of irradiance at 1.5, 15, or 75 μmol·s-1·m-2, respectively. Keeping imbibed seeds in darkness for ≥2 days before light exposure caused reduced total germination percentages (G), delayed achieving 50% of the final germination percentage (T50), and increased the days between 10% and 90% germination (T90-T10). Light for 6 hours daily at 1.5, 15, or 150 μmol·s-1·m-2 promoted high G and rapid and uniform germination, but daily 12 to 24 hours of irradiance decreased G and increased T50 and T90-T10. Estimated rates of decline (increase) in G, T50, or T90-T10 with each added day of light (darkness) or increasing daily hours of light were measured by fitting regression equations. Impatiens seed germination was promoted by the initial 1 to 3 days of light, but light inhibited radicle extension in the latter germination stages.
Osmotic Seed Priming of Rudbeckia fulgida Improves Germination and Expands Germination Range
Authors: Fay Amy M. , Bennett Mark A. , Still Steven M.
Published: February 2019

Low-vigor seeds of black-eyed Susan (Rudbeckia fulgida Ait.) primed in aerated -1.3 MPa KNO3 for 7 days at 30C in darkness had double the total germination percentage at 30C and one-half the mean time of germination as nonprimed seeds. Priming the seeds in polyethylene glycol rather than KNO3 generally resulted in lower total germination percentage and longer mean time of germination. Osmotic priming increased total germination percentage and germination rate of seeds germinated at 21.9 to 32.2C, but the priming benefit on total germination percentage was greater at ≤27.6C. Total germination percentage of primed and nonprimed seeds was highest at 28.8 to 32.2C.
Fertilizer Concentration and Leaching Affect Nitrate-Nitrogen Leaching from Potted Poinsettia
Authors: Yelanich Mark V. , Biernbaum John A.
Published: February 2019

The influence of fertilizer concentration and leaching volume on the quantity of applied N and water that were leached from a container-grown poinsettia crop (Euphorbia pulcherrima Willd.) was investigated. The NO3-N quantity leached after 71 days increased with higher NO3-N application rates (7, 14, or 28 mol NO3-N/m3) and higher leaching volumes; it ranged from 0.03 g NO3-N [7 mol·m-3, 0.00 container capacity leached (CCL)] to 7.65 g NO3-N (28 mol·m-3, 1.0 CCL). The NO3-N concentration for saturated media extracts increased with lower leaching volumes and higher fertilizer concentrations. For example, when 7 mol NO3-N/m3 was applied, NO3-N in the medium was 27.1 mol NO3-N/m3 when 0 CCL was used, but it was 8.6 mol NO3-N/m3 when 1.0 CCL was used. Shoot height and dry mass were not affected by the treatments. Leaching treatments also did not influenced leaf area, but leaf area was larger at 7 compared to 14 or 28 mol NO3-N/m3.
Combination Sprays with Benzyladenine to Chemically Thin Spur-type `Delicious' Apples
Authors: Greene Duane W. , Autio Wesley R.
Published: February 2019

BA, NAA, and carbaryl at 75, 6, and 600 mg·liter-1, respectively, were applied alone or in combination to `Starkrimson Delicious' in 1989 and `Redspur Delicious' apples (Malus domestica Borkh.) in 1990. BA was effective alone, but when combined with carbaryl it thinned excessively. Thinning failed when BA was combined with NAA because many seedless pygmy fruit were formed and they persisted until harvest. BA and carbaryl were more effective than NAA at increasing return bloom. Return bloom was more closely related to total seed count than to final set. BA improved flesh firmness at harvest and after cold storage. None of the treatments influenced the development of calcium-related storage disorders following air storage. Chemical names used: benzyladenine (BA); naphthaleneacetic acid (NAA).
DCPTA Enhances Growth and Flowering of Heliconias
Authors: Broschat Timothy K. , Svenson Sven E.
Published: February 2019

Heliconia stricta Huber `Dwarf Jamaican' were grown in 10-liter containers under full sun or 50% shade for 1 year, and H. caribaea Lamarck `Purpurea' were grown in an open field for 2.5 years. Rhizomes were soaked for 1 hour before planting or plants were sprayed with 30 μm DCPTA after two leaves had emerged. Heliconia stricta grown under full sun produced more inflorescences than those grown under 50% shade, and DCPTA-treated plants grown under shade produced more pseudostems and were taller than control plants. DCPTA-treated H. caribaea produced more pseudostems per plant than control plants during their first year, but differences in the number of pseudostems and inflorescences during subsequent years were not significant. Chemical name used: 2-(3,4-dichlorophenoxy)triethylamine (DCPTA).
Temporary Suppression of Radicle Elongation of Germinated Impatiens Seeds by Low Oxygen Concentrations
Authors: Polking Gary F. , Gladon Richard J. , Koranski David S.
Published: February 2019

Germinated Impatiens wallerana Hook. f. `Super Elfin Salmon Blush' seeds were exposed to subatmospheric O2 concentrations for 12, 24, or 48 hours at 25C. Suppression of radicle growth during a subsequent 24-hour simulated shipping period was monitored, as was plant growth during a subsequent growth cycle. One percent to 2% O2 for 12 or 24 hours limited radicle elongation to <1.0 mm during the simulated shipping period (darkness, ambient O2) and caused no permanent damage to seedlings. Suppression of radicle elongation with low O2 was greater with a 24-hour than a 12-hour exposure. Oxygen at 0% for 24 hours or at 0% to 1.5% O2 for 48 hours damaged seedlings irreversibly. These results show that specific subatmospheric O2 treatments can restrict radicle elongation of germinated seeds during subsequent shipment to a grower and that the low O2 treatment does not decrease subsequent plant growth.
`Redhaven' Peach Impact Damage Thresholds
Authors: Schulte Nancy L. , Timm Edward J. , Brown Galen K.
Published: February 2019

`Redhaven' peaches [Prunus persica (L.) Batsch] were dropped onto several impact surfaces to determine impact conditions that initiate bruising. After impact, the peaches were tested for flesh firmness and sorted into firm, soft, and very soft groups for bruise analysis. The drop height that did not bruise decreased as fruit softened. The peach shoulder area bruised most easily. A drop of only 8 mm onto a hard surface initiated bruising on a soft peach, whereas a Poron 15250 cushion could protect the peach for a ≤85-mm drop. Impact damage threshold estimates were developed for the three flesh firmness conditions. The threshold estimates and impact history information collected by an instrumented sphere can be used to develop handling equipment design and operation guidelines that essentially avoid impact bruises on peaches.
A Rapid Protocol for Evaluating Prunus Germplasm for Tomato Ringspot Virus Resistance
Authors: Halbrendt J.M. , Podleckis E.V. , Hadidi A. , Scorza R. , Welliver R.
Published: February 2019

Rooted cuttings of `Halford' and `Redhaven' peaches [Prunus persica (L.) Batsch] and `Stanley' (Prunus domestica L.) and `Marianna 2624' (P. cerasifera × P. munsoniana) plums were planted in soil containing ≈38 tomato ringspot virus-(TomRSV) infested nematodes (Xiphinema americanum sensu lato Cobb) per 100 cc. Test- and control-plant sap extracts were made from root and leaf tissues after 10, 22, and 34 weeks. Aliquots of these samples were assayed by mechanical inoculation to Chenopodium quinoa Willd. Total nucleic-acid extracts prepared from the remainder of each sample were analyzed by dot blot hybridization using a cRNA probe for TomRSV. The bioassay identified one `Stanley' and two `Redhaven' infected plants. Hybridization results indicated that two of two `Stanley', three of three `Halford', five of five `Redhaven', and zero of six `Marianna 2624' were infected. Our results demonstrate the sensitivity of molecular hybridization for TomRSV detection in Prunus and substantiate the TomRSV resistance of `Marianna 2624'.
Impact of Lawn-care Firm Characteristics on Pesticide Expenditures
Authors: Florkowski W.J. , Hubbard E.E. , Landry G.W. , Murphy T.R.
Published: February 2019

Using three types of pesticides is related to selected lawn-care firm characteristics. The data were collected through a survey of 95 randomly selected firms, which yielded 68 usable questionnaires. From that number, 50 firms specializing in lawn-care services other than mowing were selected. Statistical relationships were formulated using herbicide, insecticide, and fungicide expenditures as dependent variables. In estimated relationships, the impact of variables significantly different from zero (i.e., firm's gross revenue, number of commercial customers serviced, annual labor cost, and size of the treated commercial landscape) was in the same direction but differed in magnitude. In general, commercial account additions and firm size (measured by gross revenue) increased pesticide expenditures. Pesticide expenditures decreased, however, as the labor cost and the size of the treated commercial landscape increased. The firm's perception of pesticide regulations had no impact in the specified relationships.
Antidesiccants Applied to Packaged Rose Plants Affect Growth and Field Performance
Authors: Schuch Ursula K. , Karlik John F. , Harwood Charlene
Published: February 2019

Moisture loss from bare-root plants during postharvest handling and storage can have a significant impact on plant survival and growth during establishment. Three film-forming antitranspirants and hot wax were applied to bare-root roses (Rosa) packaged after harvesting from the field and before 13 weeks of –2C storage to determine effects on vegetative growth and flowering. Subsequently, during 15 days under simulated display conditions (22 to 32C), plants treated with hot wax resumed growth at the fastest rate compared to control or antitranspirant treatments. Hot-wax-treated plants remained at an advanced phenological stage compared to the other plants for 2 weeks following transplanting in the field. For the remaining 10 weeks of the experiment, vegetative growth and flowering development were similar for all treatments. More than 60% of the plants treated with hot wax developed moderate to severe cane damage and plant dieback. Less than 20% of the antitranspirant-treated plants were damaged. A laboratory experiment confirmed that hot wax treatment was most effective; it reduced weight loss from stem sections by 85% relative to the control. The other antitranspirants reduced weight loss by 27%.
Plant Density Effects on Single-head Broccoli Production
Authors: Jett Lewis W. , Morse Ronald D. , O'Dell Charles R.
Published: February 2019

There is a strong consumer demand for single-head broccoli (Brassica oleracea L. var. italica) that yields more florets per unit weight than bunching broccoli. Two spatial arrangements (single vs. twin row) and five plant densities (10.8, 7.2, 5.4, 4.3, and 3.6 plants/m2) were examined for single-head broccoli production. Spatial arrangement had no significant effect on any measured attribute, although the twin-row arrangement resulted in less plant damage with each harvest. For exclusive production of quality, single-head broccoli with high yields of marketable florets, 3.6 plants/m2 (46-cm within-row spacing) should be used.
Leaching Fraction and Fertilization Effects on Growth of Three Woody Legumes Inoculated with Rhizobia
Authors: Graves William R. , Anfinson Sandra R. , Lappegard Kathryn K.
Published: February 2019

Scotch laburnum [Laburnum alpinum (Mill.) Bercht.], Amur maackia (Maackia amurensis Rupr. & Maxim.), and Chinese wisteria [Wisteria sinensis (Sims) Sweet] were inoculated with compatible rhizobia and treated with leaching fractions (LF) of 0, 0.2, and 0.4 using fertilizer solutions with 3.6 and 10.7 mol N/m3 for 10 weeks. LF did not affect plant dry mass, leaf area, or stem length. Growth was higher among plants provided 10.7 mol N/m3, but only plants provided 3.6 mol N/m3 formed root nodules. We conclude that growth is not reduced by eliminating leaching during the first 10 weeks of seedling development, and that application of 10.7 mol N/m3 prevents nodulation of these species.
Nitrate, Phosphate, and Potassium Leaching from Container-grown Plants Fertilized by Several Methods
Authors: Broschat Timothy K.
Published: February 2019

Spathiphyllum Schott. `Mauna Loa Supreme' and areca palm (Chrysalidocarpus lutescens H. Wendl.) were grown for 6 months in 3.5-liter containers using a pine bark–sedge peat–sand container medium or a native sand soil. Plants were fertilized with equivalent amounts of a 21N–3P–12K fertilizer applied weekly as a liquid, monthly as a soluble granular, bimonthly as a lightly coated controlled-release, or every 6 months as a heavily coated controlled-release fertilizer. All leachates were collected and analyzed weekly for NO3-N, PO4-P, and K. Amounts of all three nutrients leached per week varied considerably in response to fertilizer reapplications or high rainfall. Nitrate leaching generally decreased over time, PO4-P leaching increased, and K remained relatively constant. Shoot dry weights of spathiphyllum were equivalent for all fertilization methods, but areca palm shoot dry weights were highest with liquid fertilization and lowest with the soluble granular fertilizer. Nutrient leaching for all three ions was highest for the soluble granules and lowest for the two controlled-release formulations.
DCPTA Ineffective as a Production Aid on Field-grown Tomato and Pepper
Authors: Hartz T.K. , Kies L.J. , Baameur A. , May D.M.
Published: February 2019

Application of DCPTA, as a seed treatment and a foliar spray, was evaluated for effects on productivity and fruit quality of processing tomato (Lycopersicon esculentum Mill.) and fresh-market pepper (Capsicum annuum L.). Two field trials for each crop were conducted in California during 1992. No DCPTA treatment was effective in increasing vegetative growth or fresh fruit yield of either crop at any site. Total soluble solids concentration and color of tomato fruits were unaffected by DCPTA, regardless of application method. We conclude that DCPTA is not a useful production aid for field-grown tomato or pepper. Chemical name used: 2-(3,4-dichlorophenoxy) triethylamine (DCPTA).
Effects of (+)-S-Abscisic Acid on the Quality of Stored Cucumber and Tomato Seedlings
Authors: Yamazaki Hiroko , Nishijima Takaaki , Koshioka Masaji
Published: February 2019

Effects of ABA on the quality of stored cucumber (Cucumis sativus L.) and tomato (Lycopersicon esculentum Mill.) seedlings were investigated in two experiments. Foliarly applied ABA (20, 100, or 500 mg·liter–1) decreased transpiration of stored, pot-grown, cucumber seedlings at 8, 15, and 20C. Seedlings stored at 15 and 20C were slender with long internodes. At these temperatures, ABA at 100 and 500 mg·liter-1 reduced plant internode length. Seedlings stored at 8C and those not stored were short, and ABA did not affect internode length. A decrease of chlorophyll content in the first leaf of seedlings stored at 20C was less pronounced with ABA. In the second experiment, the effect of a foliar ABA application on stored, plug-grown, cucumber and tomato seedlings was determined. When seedlings were stored at 20C, those sprayed with ABA did not wilt, but nontreated seedlings did wilt. No seedlings wilted when stored at 8 and 15C. These results suggest that ABA could be used to maintain the quality of cucumber and tomato seedlings stored at 15 or 20C. Chemical name used: (+)-S-abscisic acid (ABA).
SUPERFICIAL SCALD OF APPLES: A CHILLING INJURY THAT ALSO CAN BE INDUCED UNDER NON-CHILLING CONDITIONS?
Authors: Bramlage William S.
Published: February 2019

On Granny Smith apples, scald development exhibits characteristics that are typical of chilling injury. Yet, when `Cortland' and `Delicious' apples were placed in loosely closed polyethylene bags and kept continuously at 20C, scald-like injuries began to occur after 2 weeks. Lesions were predominantly expressed as lenticel spotting and as bronzing in the calyx cavity, which are not typical of superficial scald, but some typical scald lesions did develop on the shaded sides of the fruit. Lesion development decreased with later harvest of fruit. Fruit enclosed in poly bags accumulated high concentrations of α-famesene and conjugated trienes in their peel. Whether or not scald should be considered to be a chilling injury will be examined in light of these contrasting results.
PHYSIOLOGICAL CHANGES ASSOCIATED WITH LEAF SENESCENCE IN EASTER LILIES
Authors: Franco Rosanne E. , Han Susan S.
Published: February 2019

Senescence of lower leaves of Easter lilies (Lilium longiflorum Thunb.) was previously shown to be delayed with application of the growth regulators, gibberellic acid (GA3) and benzyladenine (BA). This study was done to determine the physiological effects of GA3 and BA in relation to the delay of leaf senescence. Foliar application with 500 ppm BA or GA3 delayed chlorosis and lowered respiration rate in Easter lily leaves. A combination of 500 ppm BA and 500 ppm GA3 was more effective than the individual application of each. Gibberellic acid, BA, or their combination before cold storage resulted in delayed chlorosis and lowered respiration following removal from cold storage. Treatment with growth regulators after cold storage was less effective. Senescence of leaves was not associated with ethylene since ethylene production by leaves was undetectable by gas chromatograph. In addition, pulsing or continuous treatment with silver thiosulphate (STS), an inhibitor of ethylene synthesis, did not delay foliar chlorosis. Analysis of carbohydrate levels in Easter lily leaves treated with GA3, BA, or their combination may contribute to the understanding of the physiological effects of these two growth regulators.
GROWTH AND YIELD OF GREENHOUSE TOMATO WITH CONSTANT OR DIURNAL HEATING OF ROOT AND SHOOT
Authors: Gent Martin P.N. , Ma Yong-Zhan
Published: February 2019

What is the effect of constant compared to diurnal heating of the shoot and root on growth and yield of greenhouse tomato (Lycopersicon esculentum L.)? Seedlings were transplanted on 4 or 25 Mar. 1994 into troughs that were not heated or heated to 21C by buried tubing, either constantly or for 12 h during the day or the night. The greenhouses had either 14/14C or 26/6C day/night minimum air temperatures. After 2 weeks, leaves of the 4 Mar. transplants weighed most with constant root heat and least with no heat. Roots weighed more with 14/14C than 26/6C air heat. With 14/14C air heat, only no root heat reduced leaf weight, whereas with 26/6C air heat, leaf weight was in the order: constant > day > night - no heat. After 2 weeks, leaves of the 25 Mar. transplants weighed least with no heat, and other treatments did not differ. Root heating affected yield. By 1 July, the number of fruit and the number and weight of marketable fruit produced from 4 Mar. transplants was in the order: constant heat > day > night > no heat. The 22/6C air heat increased marketable yield because fewer fruit were small, irregular, or had blossom-end rot. Root heat had no effect on yield of 25 Mar. transplants.
FACTORS AFFECTING ELLAGIC ACID CONTENT IN SMALL FRUITS
Authors: Wana Shiow Y. , Maas John L. , Galletta Gene J.
Published: February 2019

Ellagic acid, a putative anticarcinogenic compound, was detected in plants of mayhaw (Crataegus spp.), false strawberry (Duchesnea indica), strawberry (Fragaria spp.), black currant (Ribes nigrum), thornless blackberry (Rubus subgenus Eubatus), red raspberry (Rubus subgenus Idaeobatus), and cranberry (Vaccinium macrocarpon). Large differences in ellagic acid contents have been found among species and cultivars and also among tissues. Ellagic acid content in plant tissues is also affected by environmental factors and shows a seasonal variation in strawberry leaves. A decrease in ellagic acid content of leaves was associated with seasonal decreases in photoperiod and temperature from September to December. Ellagic acid content in the leaves of red raspberry infected with orange rust showed more than a 3-fold increase compared to healthy leaves.
NUCLEAR MAGNETIC RESONANCE IMAGING OF FUNGAL INFECTIONS IN STRAWBERRY FRUIT
Authors: Maas John L. , Line M.J.
Published: February 2019

We report the use of nuclear magnetic resonance (NMR) imaging to detect differences in invasion and colonization of fruit by pathogens (Botrytis cinerea, Colletotrichum acutatum, and Phytophthora cactorum), and bruise wounds are sharply distinguishable from healthy fruit tissue by their T1 times. Digitized images from T1 images clearly show two or more zones of pathogen activity in fruit tissue. The innermost zone corresponds to the area of greatest invasive activity at the leading margin of the infection. A second zone corresponds to the area of tissue that has been killed and is being degraded by the pathogen. Sometimes, a third zone is present at the outer border of the lesion and this correspond to where aerial sporulation may occur. Images of bruises, however, are uniform with no apparent gradations in T1 characteristics. Detection of fruit deterioration and decay is important in understanding and controlling postharvest loss of fruit crops. The nondestructive nature of MRI provides a means to quantify the process of decay development and control measures applied to fruits.
Mechanical Harvesting and Dehulling of Six Strawberry Cultivars after Four Hand-pickings
Authors: Khanizadeh Shahrokh , Lareau Michel J. , Buszard Deborah
Published: February 2019

An experiment was conducted to evaluate the mechanical harvesting and processing suitability of four standard strawberry [Fragaria ×ananassa (Duch.)] cultivars (`Kent', `Glooscap', `Bounty', and `Midway') and the recent introductions `Chambly' and `Oka'. `Kent', `Glooscap', `Oka', and `Chambly' had the highest yields and heaviest fruit. Similar percentages of berries of all cultivars were destroyed by the harvester. `Oka' and `Midway' were not suitable for this type of mechanical harvesting due to their susceptibility to bruising during harvest. Based on total marketable fruit harvested mechanically, `Chambly' was the most and `Oka' was the least adapted cultivars for this particular harvester. `Chambly' and `Glooscap' were easiest to decap, followed by `Bounty', `Oka', and `Midway'. None of the cultivars tested were suited ideally for machine harvesting, and further breeding is required to produce well-adapted cultivars.
Irradiance Level and Duration Required to Terminate the Dormancy of Begonia ×semperflorens Seed
Authors: Carpenter William J. , Ostmark Eric R. , Cornell John A.
Published: February 2019

Begonia ×semperflorens-cultorum Hort. `Prelude Scarlet' seeds varied within irradiance treatments in the irradiance level and duration that they required to reach the light saturation value and germinate. At high photosynthetically active radiation (PAR), seeds required light for only part of the germination period to terminate photodormancy. Germination >90% was achieved after 4 and 1 day of 24 hours/day exposure to PAR at 15 and 150 μmol·m–2·s–1, respectively, but 82% germination occurred after 4 days of irradiance at 1.5 μmol·m–2·s–1 at 27C. Fewer days to 50% of final germination (T50) and between 10% and 90% germination (T90 – T10) were required when light saturation was achieved after 1 day at high PAR rather than after 4 days at a low PAR level. The total PAR that seeds received during 6, 12, or 24 hours of light daily determined the total percentage of the seeds that germinated. Seeds receiving 150 μmol·m–2·s–1 continuously for ≥24 hours achieved 90% germination, but 6 or 12 hours daily at this irradiance level required 4 days and 3 days, respectively. Trends in total germination percentages (G), T50, or T90 – T10 with increased PAR levels, hours of light daily, or days of light were found by fitted regression equations and Tukey's hsd procedure. Begonia seed germination was promoted by PAR levels of 1.5 to 150 μmol·m–2·s–1 for periods ≤4 days, with darkness thereafter until cotyledon emergence.
Cultivar, Photoperiod, and Gibberellin Influence Shoot Elongation and Photosynthetic Capacity of Hardy Azaleas
Authors: Ballantyne David J.
Published: February 2019

In a greenhouse experiment involving 13 hardy azalea (Rhododendron spp.) cultivars, `Noordthiana' and `Treasure' had the highest rate of shoot elongation and the highest photosynthetic capacity (Pcap) during the summer. In winter, `Treasure' had a high rate of shoot elongation and Pcap, but `Noordthiana' had a high rate of shoot elongation and low Pcap. Long days or GA3 sprays stimulated shoot elongation but not Pcap of certain cultivars. GA3 was effective in stimulating shoot elongation of `Vuyk's Scarlet' if plants were given supplemental photoperiods under natural winter (short) photoperiods. Cultivars with a high rate of shoot elongation and Pcap likely will produce salable plants in a shorter time period than slower growing cultivars because less time elapses between prunings. Production time can be decreased further with GA3 sprays, especially with GA3 applications in combination with supplemental photoperiods during the short days of winter. Chemical name used: gibberellic acid (GA3).
Development of a Polyethylene Mulch System that Changes Color in the Field
Authors: Graham Heather A. Hatt , Decoteau Dennis R. , Linvill Dale E.
Published: February 2019

A polyethylene mulch system that changes its predominant surface color from black to white in the field has been developed and used to grow tomatoes (Lycopersicon esculentum Mill. cv. Mountain Pride) and squash [Cucurbita pepo var. melopepo (L.) Alef. cv. Dixie Hybrid]. The system uses a black photodegradable polyethylene mulch placed on top of a white nondegradable polyethylene mulch (photodegradable mulch overlay system). As the black photodegradable mulch degrades with increasing exposure to radiation, the white mulch surface is exposed. Differences among plastic systems in the percentage that breaks down may be explained by differential shading of the mulch by the vegetative growth of the crops. None of the formulations of the Plastigone brand photodegradable mulches in the photodegradable mulch overlay system had an effect on tomato or squash production. As the color of the system changed from black to white, soil temperatures under the mulch decreased. Tomato production remained unaffected in one of the two years as long as the mulch remained black for at least the first 20 days during that season. In year 2, the controlled mulch system color change affected neither tomato nor squash production relative to nondegradable white and black mulches used as controls.
Quality of `Sharpblue' Blueberries after Electron Beam Irradiation
Authors: Miller W.R. , McDonald R.E. , Smittle B.J.
Published: February 2019

Freshly harvested `Sharpblue' blueberries (Vaccinium spp.), a hybrid of complex parentage (Sharpe and Sherman, 1976), were irradiated by electron beam at 0, 0.25, 0.5, 0.75, or 1.0 kGy to determine its effects on condition and quality after treatment and subsequent storage. Berry firmness was not affected by increased doses following 1 or 3 days of storage at 1C, but it declined with higher doses when stored for 7 days at 1C. In general, berry flavor and texture declined as dosage increased; however, neither flavor nor texture were rated unacceptable by a sensory panel. Weight loss, decay, soluble solids concentration, acidity, pH, skin color, or waxy bloom were not affected by dosage or storage.
`Eureka' Lemon Chilling Injury
Authors: Underhill Steven J.R. , McLauchlan Richard L. , Eaks Irving L.
Published: February 2019

In accordance with the currently approved Australian citrus disinfestation protocol for export to Japan, degreened `Eureka' lemons [Citrus limon (L.) Burm.] were cold-stored for 2 weeks at 1C. Following cold treatment, fruit were stored at 5C for 3 weeks, then transferred to 20C for an additional week to simulate transportation and handling. Fruit harvested early in the season were more susceptible to chilling injury than fruit harvested later, with 62% having lesions >1 cm2 after 2 weeks at 1C. Most of the chilling injury occurred after subsequent storage (at 5C) rather than immediately after the 1C treatment. Injury was different from surface pitting or oleocellosis, manifesting as large uniform surface lesions 2 to 3 cm in diameter that rapidly discolored following storage at 20C. Although the oil glands were flattened, the collenchyma layer immediately above the oil gland remained intact. Cellular discoloration was localized around the oil gland, possibly indicating a lateral release of oil gland contents. Nondegreened late-season fruit developed substantially lower levels of chilling injury.
Culling Tomatoes with External Symptoms of Irregular Ripening Is of Limited Benefit
Authors: Powell Charles A. , Stoffella Peter J.
Published: February 2019

Mature-green and mature-red tomato (Lycopersicon esculentum Mill.) fruit were harvested from spring- and fall-grown plants infested with sweet potato whitefly (SPWF; Bemisia tabaci Gennadins). The mature-green fruit were either ripened at 20 to 22C or cold-stored at 10 to 13C for 3 weeks and then were allowed to ripen at 20 to 22C. There was no significant difference in the appearance of either external or internal tomato irregular ripening (TIR) symptoms between the two storage–ripening regimes or in the appearance of internal TIR symptoms among the two storage regimes and vine-ripened tomatoes. Thus, removing the tomatoes from the SPWF during ripening does not reduce TIR symptoms. About half of the mature-green tomatoes, ripened with or without cold storage (10 to 13C), developed no external TIR symptoms, but about half of these tomatoes had internal TIR symptoms. About one-third of the tomatoes developed external symptoms during ripening, but these symptoms disappeared after ripening was complete. A high percentage (71%) of these tomatoes with external symptoms also had internal symptoms. The remaining tomatoes developed external TIR that did not disappear, and almost all of these tomatoes had internal symptoms. These data suggest that culling tomatoes that develop external TIR during ripening will reduce but not eliminate tomatoes with internal TIR from the fresh-fruit market.
Inheritance of Resistance to Zucchini Yellow Fleck Virus in Cucumis sativus L.
Authors: Gilbert-Albertini F. , Pitrat M. , Lecoq H.
Published: February 2019

Zucchini yellow fleck virus (ZYFV) is a potyvirus that occurs in cucurbits grown in some Mediterranean countries. `Marketer' cucumber responded to ZYFV infection with a severe mosaic, stunting, and leaf and fruit deformation. A high level of resistance to this virus was found in a single plant selection of `Taichung Mou Gua' (TMG) cucumber from Taiwan. In F2 and backcross populations involving TMG × `Marketer', the resistance to ZYFV was determined to be conferred by a single recessive gene, to which the symbol zyf is assigned.
Evaluation of Capsicum Germplasm for Sources of Resistance to Rhizoctonia solani
Authors: Muhyi Rejah , Bosland Paul W.
Published: February 2019

A reliable screening method to detect Rhizoctonia solani Kuhn resistance in chiles (Capsicum annuum L.) was developed using infested corn (Zea mays Bonaf.) kernels as inoculum. The most aggressive New Mexican isolate of R. solani (PWB-25) was used to screen 74 Capsicum accessions for resistance to root rot caused by the fungus. The accessions differed in resistance, with disease ratings ranging from 2.9 to 8.6 on a 0 (no disease) to 9 (seedling dead) scale. The percentage of resistant plants, those in the interaction phenotype index class 0, 1, 2, and 3, ranged from 2.4% to 77.1%. Nineteen accessions representing four species had ≥50% resistant individuals and would be useful in breeding programs.
Adaptation of Pigeonpea (Cajanus cajan Millsp.) to a Loamy Sand Site in Minnesota
Authors: Sauter K.J. , Gingera G.R. , Davis D.W.
Published: February 2019

Pigeonpea, a subtropical legume, was successfully grown in a high-latitude (≈45°N) environment. Four short-season pigeonpea accessions from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) were subjected to three cycles of pedigree selection. Performance trials (175,000 plants/ha) were conducted on loamy sand with dryland and irrigated sites in 1991 and 1992. Thirty-eight S3-derived lines from ICRISAT ICPL 83004 were used in both years and seven S3-derived lines from ICRISAT P 2125 and ICRISAT ICPL 85010 were added the second year. Differences (P ≤ 0.05) in seed yield (kg·ha–1) were observed among the S3 lines, with a maximum yield of 1468 kg·ha–1. The lines also differed (P ≤ 0.05) for harvest index (HI), calculated as the ratio of seed yield to shoot total dry matter (TDM) with a maximum of 0.48 (line MF-26). Dryland seed yield was strongly correlated with TDM (r2 = 0.98), HI (r2 = 0.92), and early bloom (r2 = 0.76). In a time-of-planting comparison of seven lines in 1992, seed yield was highest (754 kg·ha–1) at the earliest (29 Apr.) planting date and declined progressively to 178 kg·ha–1 at the latest (2 June) planting date, while HI decreased from 0.42 to 0.12. Plants were shorter at maturity in the earliest planting date.
COMPARATIVE YIELD OF FIVE SWEETPOTATO CULTIVARS PLANTED IN SINGLE AND DOUBLE ROWS
Authors: Khan V.A. , Stevens C. , Wilson M.A. , Lu J.Y. , Rhoden E.G. , Collins D.J. , Brown J.E.
Published: February 2019

In 1994, a study was conducted in split-plot design to determine the effect single- and double-row plantings would have on the yield of five sweetpotato cultivars. `TU-1892', `Carver', `Jewel', `TU-82-155', and `Georgia Jet' were planted on a raised shaped bed 2 feet wide. All recommended fertilizers were banded in the center of the bed and plants then were placed 6 inches away on both sides of this band for the double rows; single rows consisted of plants placed only on one side of the fertilizer band. Plants were spaced 12 inches apart within rows, and the rate of fertilizer used for single and double rows was the recommended rate for single rows. All plots were sidedressed with an additional 80 lbs/acre of K at the time of flowering. Marketable yield data showed that double-row planting of `Jewel', `TU-82-155', and `TU-1892' resulted in 36%, 38%, and 33% significant increase in yield, respectively, compared to single-row plantings. Double-row planting also significantly increased the yield of U.S. no. 1 `TU-82-155', `Jewel', and `Carver' sweetpotatoes by 40%, 43%, and 19%, respectively. All cultivars used in the study showed a significant increase in canners yield when planted in double vs. single rows. The results also indicated that `TU-1892', `Jewel', and `TU-82-155' may be more efficient in fertilizer use because higher yields were obtained in double-row plantings at the single-row fertilizer rates without the additional application of fertilizers.