bluuebunny/crossref_metadata_2025 huggingface dataset:
CALLUS FORMATION IN BUD UNIONS OF `JONAGOLD' ON `MARK' ROOTSTOCK
Authors: Warmund Michele , Barritt Bruce , Schaffer Karen
Published: February 2019

`Mark' rootstock is a relatively new dwarfing rootstock that induces precocity in apple trees. While `Mark' has desirable horticultural characteristics, it has been difficult to propagate in some areas of the United States. To determine the optimum budding date at two climatically diverse locations, `Jonagold' buds were chip-budded onto `Mark' rootstock on 20 July, 10 Aug., 31 Aug. and 21 Sept. 1989 at Atlas, Illinois and Wenatchee, Washington. Prior to budbreak, unions were sampled from each budding date and the callus, bud plate and rootstock were measured and photographed. Trees budded and grown in Illinois had more callus growth than those budded in Washington. In Illinois, the callus of trees budded on 20 July averaged 3.2 mm., whereas those budded on 21 Sept. averaged 1.0 mm. Trees grown in Washington had 0.4 mm of callus at both budding dates. Callus growth will be correlated with union compatibility and strength in Nov. 1990.
NITROGEN RATES FOR POTATOES-YIELDS AND TISSUE TESTS
Authors: Minotti Peter L. , Halseth Donald E. , Sieczka Joseph B.
Published: February 2019

Experiments were conducted at Freeville, NY and Riverhead, NY with 0-280 kg/ha of N banded. Tissue samples (both petioles and whole leaves) were taken 5 times starting 32 days from planting. There was a marked increase in yield and specific gravity from the first 112 kg/ha of N and in most cases from an additional 56 kg/ha of N. Both petiole and whole leaf nitrate were sensitive to changes in fertilizer rate that resulted in yield changes. We were encouraged by results obtained with “quick” tests on fresh sap since the pattern paralleled that obtained with traditional lab analysis of dried ground petioles. Although nitrate concentrations did not vary markedly across the varieties used there were substantial differences due to location even when the yield response curve was similar. Rate of N for rate of N, the Freeville samples were substantially higher in nitrate than those from Long Island, except at the 0 N rate, suggesting that the difference is not due to soil residual N.
NUTRIENT CONCENTRATIONS IN SOIL SOLUTIONS FOR MUSKMELONS AS INFLUENCED BY FERTILIZER TREATMENT
Authors: Wilcox Gerald E. , Adler Paul R. , Errebhi Mohamad
Published: February 2019

A study was made to investigate the effects of liming and N source fertilization on soil acidity, nutrient uptake an yield of muskmelon on a Princeton loamy-sand (fine sandy, mixed, mesic, type Hapludalf) at Southwest Purdue Agricultural Center, Vincennes, IN. The experiment consisted of lime and no lime treatments with five N treatments of 0 N, 50 kg·ha-1 N as urea and 100 kg·ha-1 N as urea, NH4NO3, and (NH4) SO4. The unlimed soil tested pH 4.6, 4.2 and 4.1 and the limed soil was pH 5.5, 5.6 and 5.2 with 100 kg N·ha-1 as urea, NH4NO3 and (NH4) SO4, respectively. With NH4NO3 the NO3-N declined from 268 ppm on 6/1 to 64 ppm on 7/7 in the saturation extract (SE). Highest NH4-N was from (NH4)2SO4 followed by NH3NO4 and urea. The NH4-N concentration from (NH4)2SO4 in the SE decreased from 152 ppm to 19 ppm during the season on unlimited soil and from 56 ppm to 8 in the SE decreased from 152 ppm on limed soil. Symptoms of Mn toxicity in the leaves became apparent on unlimed plots 7 weeks after transplanting. As the rate of N increased in the range of 0, 50 and 100 kg·ha-1 from urea the Mn contents were 372,459 and 607 ppm respectively. The muskmelon fruit yield increase due to 100 kg N·ha-1 was 13279 kg·ha-1, 12161 kg·ha-1 and 8502 kg·ha-1 for ureas, NH4NO3 and (NH4)2SO4 respectively.
WATERMELON RESPONSES TO MEHLICH-I-PREDICTED PHOSPHORUS FERTILIZER PROGRAMS
Authors: Hochmuth George , Hanlon Ed
Published: February 2019

Vegetable P fertilization recommendations in Florida are based on a soil test using the Mehlich-I (double-acid) extractant. For several Florida vegetables, including watermelon, there is a lack of crop correlation and extractant calibration data. Phosphorus fertilizer studies were conducted on sites with soils ranging in Mehlich-I P indices from 4 to 30 mg·kg-1. There was a quadratic yield response on soils testing 4 mg·kg-1 P with yield maximizing at about 70 kg·ha-1 fertilizer P. Watermelon did not respond to P additions on soils testing greater than 30 mg·kg-1 of Mehlich-I P.
GENETIC ENGINEERING OF THE ZUCCHINI YELLOW MOSAIC VIRUS COAT PROTEIN GENE FOR EXPRESSION IN PLANTS.
Authors: Fang Guowei , Grumet Rebecca
Published: February 2019

Zucchini yellow mosaic virus (ZYMV), a potyvirus, can cause major losses in cucurbit crops. With the goal of genetically engineering resistance to this disease we have engineered the ZYMV coat protein gene into a plant expression vector. The complete coat protein coding sequence, or the conserved core portion of the capsid gene, was attached to the 5' untranslated region of tobacco etch virus (TEV) in the pTL37 vector (Carrington et al., 1987, Nucl. Acid Res. 15:10066) The capsid constructs were successfully expressed by in vitro transcription and translation systems as verified by SDS-PAGE and ZYMV coat protein antibody. The constructs were then subcloned using polymerase chain reaction and attached to the CaMV 35 S transcriptional promoter on the CIBA-GEIGY pCIB710 plasmid. The constructs containing the CaMV 35S promoter, the 5' untranslated leader of TEV, and ZYMV coat protein sequences were then put between the Agrobacterium tumefaciens left and right borders in the pCIB10 vector and transferred to A. tumefaciens strain LBA4404 by triparental mating. These vectors are now being used to transform muskmelon and cucumber; resultant transgenic plants will be tested for ZYMV coat protein expression.
NITROGUANIDINES, A NEW FAMILY OF PGRs, INHIBIT SENESCENCE OF LEAVES AND VEGETABLES
Authors: Pavlista Alexander D.
Published: February 2019

Nitroguanidines are a new family of synthetic plant growth regulators (Speltz, Walworth, and Pavlista 1986. US Patent #4, 594, 092) These compounds have cytokinin-like activity such as delaying senescence. Three compounds are AC239, 604, AC243, 419 and AC132, 654 The first two are phenyl and the latter is a benzyl nitroguanidine. Examples of anti-senescence activity of these compounds are: 1. sunflower leaves, 2. tobacco leaves, 3. leafy lettuce, 4. kale, 5. collards, and 6. Swiss chard. The senescence of cut ornamental flowers is also inhibited. Examples are gladiolus and daffodils. Along with delaying senescence, AC239, 604, for example, increased leaf size, thereby, increasing yield of leaf crops such as tobacco (Pavlista and Templeton. 1987. PGRSA Proc.) and lettuce.
ELEVATED MICROSPRINKLER BENEFITS CITRUS TREES IN A SEVERE ADVECTIVE FREEZE
Authors: Parsons Larry R. , Wheaton T. Adair
Published: February 2019

Undertree microsprinkler irrigation has protected 1 or 2 year old trees to a height of 1 meter during severe advective freezes. During the severe December 1989 freeze, microsprinklers elevated to 0.9 meter protected 5 year old citrus trees to a height of 2 meters. Limb breakage due to ice loading was negligible. Protection was achieved with water application rates less than half that required by some overhead sprinkler models. Survival is attributed to 1) continuous spray from the microsprinkler rather than periodic spray from a rotating overhead sprinkler, and 2) effective localized application rate on branches intercepting spray is more than average overall spray application rate. Elevated microsprinklers provide freeze protection to a greater height and allow for more rapid post-freeze recovery.
GROWTH STUDIES WITH SNAP BEANS TO PREDICT HARVEST
Authors: Daningsih Entin , Coffey D. L. , Logan J. , Mullins C. A.
Published: February 2019

Studies were initiated in 1989 to characterize phonological events with corresponding growth and development phenomena of `Eagle' and `Provider' snap beans (Phaseolus vulgaris L.) Ten plantings at approximately 15 day intervals were made at Knoxville, TN from April 17 through July 27. Days to reach growth stages V0 thru R7 were recorded for each cultivar for each planting date. Air temperature, total radiant energy, wind speed and relative humidity were recorded hourly throughout the 171 day test period. Growing degree days (GDD) computed by 8 methods and growing degree hours (GDH) computed by 2 methods were regressed against plant developmental stages. GDD and GDH, along with pod size and pod fiber content, will be discussed as possible indices for predicting harvest maturity. With the methods used to calculate heat summation in this study, GDD and GDH from planting to pod maturity ranged from approximately 550 to 975 and 9,700 to 20,000, respectively.
SUGAR ACCUMULATION IN FRUIT OF CULTIVATED AND WILD SPECIES OF TOMATO
Authors: Stommel John R.
Published: February 2019

Sugar accumulation throughout fruit development in the cultivated tomato (Lycopersicon esculentum) and a wild green-fruited species (L. peruvianum) are being examined. Results obtained using HPLC demonstrate that the fruit of L. peruvianum accessions accumulate the disaccharide, sucrose, in addition to the monosaccharides, glucose and fructose, common to L. esculentum. When detectable, sucrose in the L. esculentum cultivar FM6203 was present at very low levels throughout development. Analysis of mature fruit of L. esculentum var. cerasiforme, L. pimpinellifolium, and L. cheesmanii accessions indicate glucose and fructose as the primary storage sugars. Similar to L. peruvianum, mature fruit of the green-fruited species, L. hirsutum f. typicum and L. hirsutum f. glabratum, accumulate sucrose in addition to glucose and fructose.
COMPARISON OF GROWTH REGULATOR SPRAYS FOR POINSETTIA HEIGHT CONTROL
Authors: Sanderson Kenneth C.
Published: February 2019

Cuttings (3 per 1.5-liter pot) of `Annette Hegg Lady' and `V-14 Glory' poinsettias were directly rooted under mist and subsequently grown for treatment with various growth regulator sprays. Sprays of 40 ppm and 61 ppm paclobutrazol, 2,500 ppm daminozide plus 1,500 chlormequat, 20 ppm and 40 ppm ethephon, 150 ppm ancymidol, 5,000 ppm daminozide, 20 ppm and 40 ppm uniconazole, and 25 ppm and 50 ppm flurprimidol were applied to the plants with a low pressure, high volume sprayer on October 23. Sprays of 40 ppm uniconezole caused the most height retardation with both cultivers, however 4000 ppm ethephon, 20 ppm uniconazole and 61 ppm paclobutrazol often gave comparable height retardation. Bract area of both cultivars was most severely retarded by 40 ppm uniconazole and 4,000 ppm ethephon.
APPLICATION OF DORMANT OIL TO PEACH TREES MODIFIES INTERNAL BUD-TWIG ATMOSPHERE
Authors: Deyton Dennis E. , Sams Carl E. , Cummins John C.
Published: February 2019

Treatments of dormant oil, at rates of 0, 3, 6, 9, or 12 % (v/v), were sprayed until drip on four year old `Biscoe' peach trees on February 6, 1990. Another treatment was applied as a split application with 6 % applied on the previous application date and a second application of 6% solution applied on February 12. The internal atmosphere of bud and twig was modified by the oil treatment. The internal concentration of CO2 was elevated the morning following treatment and continued higher than the control for seven days. A second application Of 6% oil resulted in additional elevation of internal CO2. External evolution of CO2 of all oil treated twigs was 6 to 18% lower than the control 8 days after treatment. Bud phenology and bloom date of trees receiving higher rates of oil were slightly delayed.
SPRAY DROPLET/CHEMICAL DEPOSIT INTERACTION WITH LEAF SURFACES
Authors: Bukovac M.J. , Reichard D.L.
Published: February 2019

Most growth regulators and crop protection chemicals are delivered to the plant as aqueous sprays. Spray droplet:plant surface interaction is central to establishing spray and, hence, dose retention by the plant. Further, the nature of chemical deposition from spray droplets plays an important role in determining the efficiency of the active ingredient (a.i.). Using scanning electron microscopy and dispersive x-ray analysis, we investigated chemical deposit formation of selected growth regulators (e.g. ethephon, 2,4, 5-TP, TIBA) on leaf surfaces differing in wettability and surface fine-structure. The a.i. frequently deposited in the form of an annulus on droplet drying, and the degree of spreading was related to surface tension of the spray solution, and wettability, fine-structure and morphology of the leaf surface. Marked differences were observed in spreading following impaction on veins vs. interveinal areas of leaves of Prunus and Pyrus sp. The epidermis over veins was more readily wetted leading to rapid lateral diffusion along veins. Surfactants (e.g. Tween 20, Regulaid) altered the deposition pattern, expanding the annulus and increasing spreading on the leaf surface.
INTERACTION BETWEEN OXYGEN LEVEL AND THE RIPENING OF `GALA' APPLES
Authors: Solomos T. , Kannellis A. , Walsh C.S.
Published: February 2019

In the past three years we have studied the effects of oxygen on the maturation and ripening of `Gala' apples. Fruit-respiration, the onset of the climacteric rise in ethylene evolution and the rate of increase in ethylene production were measured. The effects of oxygen on softening and titrable acidity were also assessed. The delay in the onset of the climacteric rise in ethylene evolution shows enzymatic-type kinetics, with saturation levels of about 8-10% oxygen. Treatment with pure oxygen was highly detrimental; it induced visual symptoms of low-oxygen damage and high levels of ethanol. The slope of the rise in ethylene evolution is also a function of oxygen concentration, with an apparent Km for oxygen lower than that which delays the climacteric onset. The effect of oxygen on respiration is dependent on the physiological state of the fruit. In preclimacteric fruits, levels of oxygen between 2 and 8% eventually decrease respiration. Calculations of internal oxygen levels indicate that the diminution of respiration results from decreased metabolic activity in response to hypoxia.
ESTABLISHING CULTURES FROM MATURE PECAN EMBRYO EXPLANTS ON MEDIA WITH LOW WATER AVAILABILITY
Authors: Obeidy Ahmed , Smith M. A. L.
Published: February 2019

Endophytic fungi associated with mature pecan nuts (cultivars `Smart', `Desirable' and `Owens') prevented successful, contaminant-free. in vitro culture of embryo explants, even after rigorous surface disinfestation of the nuts and careful aseptic shelling. Disinfestation with sodium hypochlorite after removing the shells was also unsuccessful, because even dilute concentrations which were ineffective against the fungal contaminants destroyed embryo viability. An alternative disinfestation technique is required to establish in vitro cultures from mature pecan explants. Explanting media with low water availability were developed to capitalize on the relatively stringent requirement of most fungal contaminants for free water. The explanting media were supplemented with 0.9-1.5% agar. Other media components were selectively included or omitted to test their influence on water activity and fungal growth. After four weeks of culture, the incidence of contamination was reduced to 30% or less on modified explanting media, compared to 100% loss to contamination on control medium (0.5% agar). The brief initial culture period effectively eliminated fungal contamination from cultures by plasmolyzing fungal hyphae or denaturing fungal protein, without effecting pecan embryo viability. Cultures remained contaminant-free after transfer to control medium. Axillary and adventitious bud development from disinfested embryo axes was subsequently induced in a medium with 18 μM BAP and 5 μM IBA, and regeneration from cotyledon explants was accomplished in a medium with 50 μM NAA. This disinfestation technique allows mature pecan embryo explants to be used in biotechnology.
ENHANCED REGENERATION OF SHOOTS FROM PEACH CELLS INFECTED WITH A SHOOTY MUTANT STRAIN OF AGROBACTERIUM.
Authors: Smigocki A. , Hammerschlag F.
Published: February 2019

Immature `Redhaven' peach (Prunus persica L. Batsch) embryos were infected with Agrobacterium tumefaciens strain tms328::Tn5 carrying the functional cytokinin gene. Shoots were regenerated from callus grown on MS medium without added phytohormones and subsequently rooted on half-strength MS medium with 2.8 -naphthaleneacetic acid. These plants exhibited an increased frequency of branching in vitro. Low levels of cytokinin gene transcripts were detected in these cells by Northern analysis, and using an ELISA assay, the cytokinins zeatin and zeatinriboside were determined to be on the average 30-fold higher. From these results, the expression of the cytokinin gene appears to promote growth of cells in the absence of phytohormones thus serving as a marker for transformation and a promoter of morphogenesis without a 2,4-dichlorophenoxyacetic acid inductive step.
GAS EXCHANGE RATES BY A STAND OF SOYBEANS GROWN IN A TIGHTLY SEALED CHAMBER
Authors: Wheeler R.M. , Corey K.A. , Sager J.C. , Mackowiak C. L. , Knott W.M.
Published: February 2019

Soybean plants [Glycine max (L.) Merr. cv. McCall] were grown from seed to harvest (90 days) in NASA's Biomass Production Chamber. The chamber provides approximately 20 m2 of growing area with an atmospheric volume of 113 m3. Photosynthesis and respiration rates of the stand were tracked by monitoring CO2 increase during the 12-h dark period and the subsequent drawdown to controlled set point (1000 ppm) when the lamps were turned on each day. Stand photosynthesis [under 875 μmol m-2 s-1 photosynthetic photon flux (PPF)] peaked at 35 μmol m-2 s-1 at 30 to 35 days after planting (DAP) and averaged 22 μmol m-2 s-1 throughout the life cycle. Dark period respiration peaked near 8 μmol m-2 s-1 at 30 to 35 DAP and averaged nearly 5 μmol m-2 s-1 throughout the life cycle. Prior to full canopy closure near 30 DAP, the light compensation point (LCP) for stand photosynthesis was lass than 100 μmol m-2 s-1 PPF; by 54 DAP the LCP had increasad to 175 μmol m-2 s-1. Stand transpiration rates peaked at 8.2 L m-2 day-1 at 40 to 45 DAP and averaged 4.3 L m-2 day-1 throughout growth.
COWPEA HARVEST SCENARIOS AND EDIBLE BIOMASS PRODUCTION UNDER CONTROLLED ENVIRONMENTS
Authors: Schönfeld Manette , Mitchell Cary A.
Published: February 2019

CowPea (Vigna unguiculata (L.) Walp.) is a candidate species for inclusion in a space-deployed Controlled Ecological Life Support System (CELSS) because it contributes to a balanced diet with its moderate protein content, high complex carbohydrate content, and low fat content, and because leaves and unripe pods as well as dry seeds are edible. Pour harvest scenarios were compared in the experimental line IT84S-2246 under controlled conditions with and without CO2 enrichment. Plants kept vegetative by removal of flowers and periodically stripped of fully expanded leaves yielded as much as either mixed-harvest scenario in which leaves were stripped at either 1- or 2-week intervals until pods started forming. The 2-week harvest scenario outyielded the 1-week scenario by 15 to 25%. The seed-only control produced the same amount of seeds as the 2-week leaf harvest scenario, but had lower total edible biomass because leaves were not harvested. Under 1000 ppm CO2, all treatments yielded from 30 to 70% more edible biomass than under non-CO2-enriched conditions. Research sponsored by NASA Cooperative Agreement NCC 2-100.
DIVERSITY, INHERITANCE, AND LINKAGE RELATIONSHIPS OF ALLOZYME CODING LOCI IN CUCUMBER (Cucumis sativus L.).
Authors: Knerr Larry D. , Staub Jack E.
Published: February 2019

The available U. S. Cucumis sativus germplasm collection (754 Plant Introductions) was electrophoretically screened for genetic diversity using 39 enzymes representing a total of 57 loci. Polymorphisms were observed at 18 loci which included g2dh, gpi1, gpi2, gr1, gr2, idh, mdh1, mdh2, mdh3, mpi2, pep-la2, pep-pap2, per4, pgd1, pgd2, pgm1, pgm3, and skdh. Appropriate crosses were set up to verify the inheritance of and test linkages among these loci. Four allozyme linkage groups have currently been identified. Representative linkages and their genetic distances include: gpi1 - mdh3 (20); pgm1 - pgd1 (25); and g2dh - pgd2 (19). Additionally, crosses were made to marker stocks to test for linkages between some allozyme loci and loci coding for resistance to downy mildew and anthracnose, long hypocotyl, divided leaf, short petiole, glabrous, compact plant, determinate, little leaf, and bitter free (bi).
TEMPERATURE, TRANSPLANT TIME, AND PLUG SIZE EFFECTS ON GROWTH AND DEVELOPMENT OF PANSY, PETUNIA, VINCA, AND IMPATIENS
Authors: Al-hemaid Abdulrhman I. , Koranski David S.
Published: February 2019

Petunia `Red Flash', Vinca `Little Blanch', Pansy `Magestic Giant Purple', and Impatien `Super Elfin Red' plugs were held in the greenhouse after they reached the saleable size in 200, 406, 512, and 800 for 1 to 3 weeks Pansy plugs were held in coolers at 40, 50, or 60F under fluorescent light for 16 hrs photoperiod for 1 to 3 weeks in 200, 406, 512, or 800 plug trays. All plants ware transplanted weekly and were grown in the greenhouse until flowering and data were collected. For plants bald in the greenhouse, plants were affected by transplanting time. As the holding time increased the final height, diameter, flower number, and fresh and dry weight of plants decreased. The flowering time was delayed by increase the holding time, regardless of plant variety, As cell size decreased, plant height, diameter, flower number, and fresh and dry weight decreased. For plants held in the coolers, the flowering time was delayed by the transplant time, regardless of cooler temperatures Plant quality was not affected by the treatment. The height, diameter, flowers number, and fresh and dry weight of plants showed a little effects by temperatures, cell size, and transplanting time.
GENETIC VARIATION FOR ANTHOCYANIN AND CAROTENE PIGMENTATION OF CARROT ROOTS
Authors: Simon P.W.
Published: February 2019

Genes for reduced carotene content (white, yellow, and pale orange) and for anthocyanin pigmentation were identified in Daucus carota PI 173687 and in progeny derived from crosses of this Plant Introduction with orange-rooted inbred lines. Monogenic inheritance for each of these root color variants was examined. Mixed cell cultures of callus derived from white and orange roots indicated autonomy of carotene gene expression in carrot cell cultures. Strategies for incorporation of carrot genes conditioning pigment content will depend upon gene combinations sought.
CHARACTERISTICS OF OLIVE FLOWER AND FRUIT ABSCISSION: SOURCES OF VARIATION IN A NATURAL POPULATION.
Authors: Martin George C. , Nishijima Chic , Early Jack D.
Published: February 2019

Olive fruit persistence is a crucial component of yield and an important factor in estimating alternate bearing potential.

Unfortunately, measurement of fruit persistence exhibit considerable variation, with coefficients of variation greater than 100. Such a high degree of variation makes field studies on questions regarding flowering and fruiting unmanageable due to the large number of experimental units necessary. To determine the source of this variation and how it might be reduced, comparisons of flower and fruit number per node were made within branches and trees over the course of two seasons. Results show that while the largest population of flowers are most distal on the branch, the central portion of the branch contains the majority of the final fruit population and has the lowest coefficient of variation. Furthermore, variation in the number of flowers and fruits is greater between branches than between nodes or trees. The implications of these data on experimental design are discussed and a design is proposed for reducing variation and labor needs.
QUANTITIES AND FORMS OF NITROGEN UPTAKE THROUGHOUT DEVELOPMENT IN CHRYSANTHEMUM.
Authors: King Joseph J. , Stimat Dennis P.
Published: February 2019

Changes in quantity and form of nitrogen used were evaluated during development of Dendranthema × grandiflora `Iridon', `Sequoia' and `Sequest' grown in hydroponic solutions containing 28 ppm NO 3- (as Ca(NO3)2) and 28 ppm NH4+ (as(NH4)2SO4). Four plants of each cultivar were harvested every ten days over ninety days. Data were collected on plant height, leaf number, flower bud diameter, and root and shoot dry weights. Nutrient solutions were changed every ten days and sampled at days 1, 5, and 10 of each cycle. Concentrations of NO3- and NH 4+ of nutrient solutions and dried plant tissues were determined by micro-Kjeldahl. Total tissue nitrogen was determined for `Sequoia' by macro-Kjeldahl. Depletion of nitrogen from solutions approximated a 1:1 ratio for NH4+:NO3- throughout the crop cycle (r = 0.96). Although the sample date × cultivar interaction was significant for both forms of nitrogen, overall patterns of nitrogen uptake were similar among cultivars. Nitrogen uptake expressed per gram of tissue dry weight was greatest in the first month of development. However, total nitrogen uptake was greatest from days 40 to 60. Developmental stages corresponding to this period are a cessation of new leaf development and flower bud diameters of approximately 1.0 cm. Nitrogen uptake decreased rapidly as flowers expanded. Correlations between morphological changes and nitrogen demands could maximize the efficiency of nitrogen applications.
SENSORY ANALYSES OF NETTED MUSKMELON FRUIT QUALITY AND PREFERENCE
Authors: Lester Gene E.
Published: February 2019

Analyses of sensory attributes from 19 netted muskmelon (Cucumis melo L.) cultivars and breeding lines showed that flavor, (r= .92) had the highest significant correlation with overall fruit acceptance, while appearance (r = .72), color (r = .71) and internal color (r = .68) were secondary, and texture (r = .41) was not significantly correlated with overall fruit acceptance. Chemical attributes of soluble solids, fresh weight, dry weight, beta-carotene, firmness, fructose, glucose, sucrose, and total sugars shoved that total sugars per g fresh weight had the highest significant correlation (r = .68) with overall fruit acceptance. Total sugars per g fresh weight was significantly correlated with flavor (r = .65). Although, sugars were correlated with flavor, sugars when compared to flavor were less important in determination of overall muskmelon fruit preference.
EFFECT OF O2 ON NORMAL AND C2H4-STIMULATED SWEET POTATO RESPIRATION
Authors: Zhou Dingbo , Solomos Theophanes
Published: February 2019

It is known that pure O2 enhances in sweet potato roots the respiratory increment produced by C2H4 (Theologis and Laties, 1982, Plant Physiol.). Our experimental results indicates that the decrease in respiration with decreasing O2 concentration is due to the restriction of an “oxidase” whose apparent Km for O2 is 5-6 fold higher than that of cytochrome oxidase. The magnitude of the apparent Km for O2 is affected by the diffusion of O2 and experiment conditions. The effect of O2 on respiratory rise produced by C2H4 is due to the curtailment of C2H4 action rather than to respiration as such. The apparent Km for O2 of this system is larger than that of respiration.
DEVELOPMENT AND IMPLEMENTATION OF SIMULATION MODELS
Authors: Kobayashi Kent D.
Published: February 2019

A simulation model consists of equations that represent the important relationships between components in a system, e.g., a plant or plant part. One of the purposes of simulation models is to simulate plant growth or plant growth processes to help further our understanding of plant growth and development. Simulation models are mechanistic or process based models that account for the physiological processes occurring in the system.

Model development involves several steps. We define the problem and defuse the system, its entities, their attributes, and important relationships. A conceptual model is often expressed visually in a relational diagram showing the components and their relationships. This diagram is formally expressed as a simulation model through the use of equations repenting the relationships in the system. We often make assumptions regarding the components and their relationships to simply the model or because of a lack of knowledge. Simulation models are generally written using a simulation language such as CSMP or STELLA® or with a programming language such as FORTRAN or BASIC. The model is verified through checking the appropriateness of the relationships and the integrity of the computer program. The model is then validated through seeing bow well it simulates the behavior of the system. Simulation models provide additional insights by enabling us to ask “What if” questions by changing of the conditions of the model and seeing the resulting changes in plant growth.
LILACS AND OTHER WOODY ORNAMENTAL FOR ALL SEASONS
Authors: Rogers Owen M.
Published: February 2019

Current lilac breeding programs at the University of New Hampshire focus on the later (June) blooming species of Syringa with goals of extending the season of bloom selecting slower growing forms and developing lines with double flowers. Progress toward these goals and others, e.g., true dwarfs, will be discussed and illustrated.

Every university in the northeast includes woody ornamentals in its program to some degree. The University of New Hampshire is an official test site for ornamental from NE-9 and NC-7 germplasm programs and the National Arboretum's new introduction program. The value of these programs and their future direction will be discussed.
BREEDING FOR RESISTANCE TO EUROPEAN CORN BORER IN SWEET CORN
Authors: Davis David W. , Lamb Elizabeth M. , Joyce Mary S.
Published: February 2019

Insect resistance in vegetable crops carries a new urgency as insecticide availability and usage become more restricted. The European corn borer (ECB) long has been the most costly sweet corn pest in the northern states, with corn earworm (CEW) and southwestern stalk borer most serious farther south. Resistance to ECB and CEW, as developed by classical methods, will be discussed. Newer methods (such as RFLPs) should speed transfer of this resistance to commercial stocks, and also facilitate transfer of resistance from other species. Gene modification and endophyte exploitation are longer-term possibilities. Resistance must be free from association with undesirable traits, such as long silk channel length (r = 0.3 to 0.4), unless consumer and processor specifications change.
POLARIZATION FOR LAND PREPARATION
Authors: Patten Kim
Published: February 2019

Soil polarization is a nonchemical pest management practice that can be used, under some circumstances, as an alternative to chemical fumigation for control of numerous weeds and soil pathogens. The efficacy of polarization is dependent on both biotic and abiotic factors. The uses and limitations of polarization for small fruit production will be discussed. Strategies for future research will be suggested.
AN ALTERNATIVE APPROACH TO GERMPLASM PRESERVATION
Authors: Whealy Kent
Published: February 2019

Seed Savers Exchange (SSE), founded in 1975, is a grassroots network of nearly 1,000 amateur growers who are working together to save heirloom vegetables and fruit varieties from extinction. In 1986 SSE purchased a 140-acre farm near Decorah, Iowa. Major projects either in place or under development at Heritage Farm include large Preservation Gardens where the seeds of 1,200 rare vegetables are multiplied each summer, Historic Apple Orchard of 600 old-time varieties, and endangered breeds of livestock and poultry. This talk will focus on the history and development of SSE, differences in the user groups serviced by the National Plant Germplasm System (NPGS) and SSE, the differing problems faced by both systems, and specific ways that NPGS and SSE can compliment each other's efforts.
PLANT GROWTH MODELS, THE FOUNDATION OF ENVIRONMENTAL CONTROL STRATEGIES.
Authors: Heins Royal D.
Published: February 2019

Environmental control computers allow regulation of greenhouse environments based on some model driven factor or factors other than fixed heating and cooling setpoints. A quantitative understanding of how environmental factors influence rate of plant development, flower initiation, and plant morphology is necessary to develop models for environmental control. The major limitation to the use of models for greenhouse climate and crop control is the lack of quantitative models. Examples of model development for environmental control will be discussed.
USING SCIENCE/TECHNOLOGY/SOCIETY ISSUES TO ACHIEVE SCIENTIFIC LITERACY
Authors: Johnson Gordon
Published: February 2019

Enabling citizens to have meaningful participation in public discussions of issues interfacing science/technology and society (STS) has long been a goal of science education. Involving students in investigating issues may be the most effective way of insuring continued involvement as adults. Global, national, and local horticultural issues can provide concepts for learning relevant science concepts, process skills, and other outcomes. Selecting and designing investigations of horticulture issues include input from both students and teacher. Questions that get at scientific concepts, technological implications, and societal concerns related to the issue give direction and scope to the study. The questions and responses can be student initiated with teacher guidance. Students gain experience in examining and discussing societal issues, recognizing interdependence of STS, and learning relevant science as well. As a result, students perceive horticulture as having relevance to their concerns rather than as an isolated discipline,
Growing Medium and Fertilization Regime Influence Growth and Essential Oil Content of Rosemary
Authors: Boyle Thomas H. , Craker Lyle E. , Simon James E.
Published: February 2019

Plants of rosemary [Rosmarinus officinalis L. (Lamiaceae)] were grown in pots containing a soilless (1 sphagnum peat:1 perlite) or soil-based (1 sphagnum peat: 1 perlite:1 field soil) growing medium and fertilized with either 12N-5.2P-12.5K controlled-release fertilizer (CRF) at 9.0 g/pot; constant liquid fertilization (LF) with 20N4.3P-16.7K at 150 mg N/liter; constant LF at 150 mg N/liter, plus CRF at 4.5 g/pot; weekly LF at 150 mg N/liter; or weekly LF at 150 mg N/liter, plus CRF at 4.5 g/pot. Constant LF plus CRF generally reduced plant height and depressed shoot fresh weight relative to other fertilizer regimes. Essential oil content was highest in plants receiving weekly LF. Plants grown in the soil-based mix were shorter, shoot fresh and dry weight tended to be lower, and essential oil yield was higher when compared to plants grown in the soilless mix. Satisfactory growth was obtained in both media when rosemary plants were fertilized with 12N-5.2P-12.5K CRF at 9.0 g/pot or weekly LF with 20N<.3P-16.7K at 150 mg N/liter.
A Rapid Method for Detection of Cold Hardiness in Roses
Authors: Karam Fadi H. , Sullivan J. Alan
Published: February 2019

Distinct differences in freezing tolerance among a cold-hardy wild rose species Rosa fedtschenkoana Regel., a garden rose, `Jack Frost', and their hybrid could be detected under laboratory conditions using 2-cm-long shoot segments with buds. The garden rose did not survive - SC, but the cold-hardy species survived freezing to -10C and the hybrid to –5C. One week of acclimation at 4C was adequate for R. fedtschenkoana; longer periods did not improve the rate of survival. Immersing tissue in 5%, 10%, or 20% sucrose during acclimation improved the rate of survival of R. fedtschenkoana but not of `Jack Frost'. Applications to rose breeding are discussed.
Use of Greenhouse Seedling Bioassays to Predict First Year Growth of Apple Trees Planted in Old Orchard Soil
Authors: Neilsen G.H. , Beulah J. , Hoguel E.J. , Utkhede R.S.
Published: February 2019

Apple seedling height after 7 weeks of growth in greenhouse pots was compared with total first year shoot growth of `McIntosh' or `Delicious' apple trees [Malus domestica (Borkh.)] on M.26 rootstock for eight orchards and five soil treatments. The apple trees were replanted in old orchard sites with the same treatments applied in the planting hole as were tested in the greenhouse. The pot test successfully predicted treatments that increased first year shoot growth in 23 of 30 opportunities. However, a less precise relationship (R2 = 0.38) existed between total first year shoot growth (Y) of `Summerland Red McIntosh' on M.26 rootstock and seedling height (X).
Market Quality of Grapefruit after Heat Quarantine Treatments
Authors: McGuire Raymond G.
Published: February 2019

The market quality and condition of grapefruit (Citrus paradisi Macf.) were compared after three heat treatments for quarantine control of Caribbean fruit flies [Anastrepha suspensa (Loew)]. Treatment by forced air at 48C for 3 hours was compared with immersions in water at either a constant 48C for 2 hours or with a gradual increase to 48C lasting 3 hours. The immersion at a constant 48C significantly increased weight loss and promoted injury and decay while reducing firmness and color intensity after 4 weeks of storage. By more slowly heating fruit in the gradient water immersion, weight, firmness, and natural color were retained, and injury was substantially reduced, but the incidence of decay remained high. No loss in quality resulted from treatment by forced hot air. These heat treatments had little effect on juice characteristics, although acidity was slightly reduced by each method of application. In taste tests, juice from fruit treated in water that was gradually raised to 48C was preferred over that of fruit treated at a constant 48C.
Ectomycorrhizae and Drought Acclimation Influence Water Relations and Growth of Loblolly Pine
Authors: Svenson Sven E. , Davies Fred T. , Meier Calvin E.
Published: February 2019

The influence of ectomycorrhizae on drought acclimation was studied in an open-pollinated family of loblolly pine (Pinus taeda L.). Seedlings inoculated with Pisolithus tinctorius (Pers.) Coker and Couch (Pt) maintained a higher shoot relative growth rate under high and low soil moisture regimes. However, fascicle area, shoot and root mass, and fascicle nutrient elemental content were similar for seedlings inoculated with Pt and noninoculated seedlings. Seedlings under low soil moisture were drought-acclimated by five 11-day drought cycles. During peak water deficit (cycle 6), drought-acclimated, Pt-inoculated seedlings had the lowest predawn fascicle water potential (ψ pd), conserved water with lowest bulk fascicle diffusive conductance (g), and maintained low g and transpiration (E) during recovery (cycle 6). Enhanced drought acclimation of Pt-inoculated seedlings was independent of plant size and fascicle nutrient content.
Ornamental Grass Tolerance to Postemergence Grass Herbicides
Authors: Hubbard Joanna , Whitwell Ted
Published: February 2019

Twelve ornamental grasses from the genera Calamagrostis, Cortaderia, Eragrostis, Erianthus, Miscanthus, Sorghastrum, Spartina, Panicum, and Pennisetum were evaluated for tolerance to the postemergence herbicides fenoxaprop-ethyl, fluazifop-P, and sethoxydim at 0.4 kg a.i./ha. Calamagrostis was uninjured by fenoxaprop-ethyl as measured by visual injury ratings, height, and foliage dry weight. Greenhouse studies evaluated the tolerance of three Calamagrostis cultivars to fenoxaprop-ethyl rates of 0.4 to 3.2 kg a.i./ha with no observed visual injury from any treatment. However, the expansion rate of the youngest Calamagrostis leaf was reduced linearly with increasing herbicide rates each day after application. The highest rate (3.2 kg a.i./ha) reduced the leaf expansion rate by 1 day and all other rates by 3 days after treatment. Leaf expansion rate differed between Calamagrostis cultivars at different times after herbicide treatment. Dry weight of Calamagrostis arundinacea `Karl Foerster' was reduced at 4 weeks after treatment but not at 10 weeks after treatment. Chemical names used: (±)-ethyl 2-[4-[(6-chloro-2-benzoxazolyl)oxy)phenoxy]propanoate (fenoxaprop-ethyl); (R)-2-[4-[[5-trifluoromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid (fluazifop-P); 2[1-(ethoxy imino)butyl]-5[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one (sethoxydim).
Pre-and Postharvest Changes in Sweetpotato Root Surface Chemicals Modulating Insect Resistance
Authors: Son Ki-Cheol , Severson Ray F. , Kays Stanley J.
Published: February 2019

Levels of major root surface components for two sweetpotato [Ipomoea batatas (L.) Lam.] cultivars that differ in susceptibility to the sweetpotato weevil [Cylas formicarius elegantulus (Summers)] were determined. Analyses were made 30 days before harvest, at harvest, after curing, and after 2 months of storage during two seasons. Significant variation in the amounts of individual components, especially boehmeryl acetate, which is known to be an ovipositional stimulant for the weevil, was found before and after harvest, with season, and between cultivars. These results suggest that variation in field susceptibility of cultivars displaying moderate levels of resistance may be due in part to seasonal variation in the level of ovipositional stimulants.
Growth Stage and Site of Application Affect Efficacy of Uniconazole and GA3 in Hibiscus
Authors: Wang Yin-Tung
Published: February 2019

Leaf blades, axillary buds, shoot tips, green bark, suberized bark, or the whole plant of container-grown Hibiscus rosa-sinensis L. cv. Jane Cowl were treated with uniconazole. Applying uniconazole (50 mg·liter-1) to axillary buds or the green bark below a bud immediately after pruning limited elongation of the first three internodes. Length of the fourth internode was unaffected, regardless of the site of uniconazole application. When used on plants with 24-day-old shoots, uniconazole (40 mg·liter -1) applied to the whole plant provided the only satisfactory height control. Leaf size was reduced by nearly 50%, with a concomitant increase (12%) in fresh weight per unit area. GA3 (50 mg·liter-1, was more effective in promoting elongation of shoots previously retarded with a drench application of uniconazole (0.1 mg/2.6-liter pot) when applied to the whole shoot, leaf blades, or shoot tip. Application of GA, only to the stein surface, whether old or young, did not effectively encourage the growth of shoots of plants previously treated with uniconazole. Chemical names used: (E)-1-(p-chlorophenyl) -4,4-dimethyl-2-(1,2,4-triazole-1-yl)-1-penton-3-ol (uniconazole); analogue of (1α,2β,4 α,4bβ,10β)-2,4a,7-trihydroxy-1-methyl-8-methylenegibb-3-ene-1,10 dicarboxylic acid 1,4a-lactone (GA3).
Lisianthus Growth and Flowering Responses to Uniconazole
Authors: Starman Terri Woods
Published: February 2019

One and two foliar spray and single-drench applications of uniconazole were applied to Eustoma grandiflorum (Raf.) Shinn (lisianthus) `Yodel Blue' to determine optimal concentrations for potted plant height control. A single uniconazole spray at 10.0 mg·liter-1 applied 2 weeks after pinching, two uniconazole applications at 5.0 mg·liter -1 applied 2 and 3 weeks after pinching, or a drench at 1.60 mg a.i. per pot applied 2 weeks after pinching gave equally good height control. At these concentrations, uniconazole was similar in its effect on plant height to daminozide foliar sprays at 7500 and 2500 mg·liter-l applied once and twice, respectively. Drenching with uniconazole at 1.60 mg a.i. per pot did not increase days to flower (DTF), whereas foliar spray applications did. Drenching did not reduce flower size, but increased flower number at time of harvest. Chemical names used: α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono(2,2-dimethylhydrazide) (daminozide);(E)-(S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-01 (uniconazole).
Bed Covers Alter Temporal Distribution of Production of Sweetpotato Transplants
Authors: Porter Wayne C.
Published: February 2019

Four bed covers (black polyethylene, perforated clear polyethylene, double-slitted clear polyethylene, and spunbonded polyester) and a bare soil control were evaluated for their effect on the number, size, and harvest time of sweetpotato [Ipomoea batatas (L.) Lam. cv. Travis] transplants. The perforated and double-slitted bed covers increased the weight and number of sweetpotato transplants compared with the control or with black polyethylene at the first harvests in 1986 and 1987. Seed roots covered with the spunbonded polyester bed cover produced more plants of greater weight than seed roots covered with bare soil at the first harvest in 1986 only. Black polyethylene treatments produced the greatest weight and number of transplants at the second harvest (8 to 12 days later) in both years. There were no significant differences in total weight and numbers of transplants among black polyethylene, or perforated or double-slitted clear polyethylene treatments in 1986. Total transplant count and weights from plots covered with spunbonded polyester were lower than those from plots with any other bed covers.
Movement of Boron Out of Tree Fruit Leaves
Authors: Hanson Eric J.
Published: February 2019

Foliar B sprays (500 mg·liter-1) had increased the B content of apple (Malus domestics Borkh), pear (Pyrus communis L.), plum (Prunus domestics L.), and cherry (Prunus cerasus L.) leaves 90%) to 185% 3 days after treatment. Boron levels in treated apple, pear, and plum leaves decreased to levels similar to nontreated leaves by 9 days after application, whereas cherry leaves required 33 days to approach levels in nontreated leaves. Movement of applied B was also studied by treating cherry leaves with B solutions enriched in the stable isotope, 10B. Isotope analysis indicated that applied B moved out of leaves and into subtending tissues. The highest concentrations of applied B were found in buds, followed by bark and wood.
Growth, Fruiting, Flowering, and Fruit Quality of Sweet Cherries Treated with Paclobutrazol
Authors: Facteau T.J. , Chestnut N.E.
Published: February 2019

Five-year-old `Napoleon' sweet cherry (Prunus avium L.) trees were treated with single-application basal drenches of paclobutrazol (PBZ) in an attempt to regulate growth and flowering. Increasing concentrations of PBZ at 0.05 to 0.30 g·cm-1 trunk diameter reduced terminal extension the year of treatment and for at least the following 3 years. Fruit count increased on wood grown before treatment but decreased as annual growth declined following treatment. Fruit/cm growth generally increased, whereas fruit per flower bud decreased as PBZ concentration increased. No differences were found in fruit size, soluble solids concentration (SSC; 13% to 14%), or firmness of cherries harvested at brine maturity. Chemical name used: β-[(4-chlorophenyl) methyll-α- (l,l-dimethylethyl) -l-H-l,2,4-triazo1e-l-ethanol (paclobutrazol, PBZ).
Production and Quality of White Asparagus Grown under Opaque Rowcovers
Authors: Makus D.J. , Gonzalez A.R.
Published: February 2019

Black and white plastic rowcovers were established over field-grown `Jersey Giant' asparagus (Asparagus officinalis L.). Spears were cut for 7 weeks. Season soil temperatures were lowest under white plastic and highest without plastic covering. Night air temperature under plastic covers was ≈ 1.4C higher than without plastic covering (control), but day air temperature was typically 10C higher under black plastic, with temperatures under white plastic intermediate. Marketable yield (t·ha-1) was improved with the use of plastics as was total yield (P = 0.05), but spear number/ha was similar in all treatments. There was no consistent treatment effect on spear diameter. Average spear weight was higher when under plastic, whereas spear length was reduced compared with uncovered spears. There were no differences among treatments in spear fiber content, but spears grown under plastic covers were higher in soluble solids content, titratable acidity, and nitrate and lower in protein, ascorbic acid, and total phenolics than uncovered spears. Quantitative differences in these constituents were also a function of whether they were from the upper, middle, or lower spear segment. Very little chlorophyll and carotenoids were produced in the absence of light, but there was a chroma (color intensity) difference between spears grown under the two plastics.