bluuebunny/crossref_metadata_2025 huggingface dataset:
218A FURTHER STUDIES EXPLORING IRON NUTRITIONAL QUALITY FROM AMARANTHUS SPECIES
Authors: Rangarajan Anusuya , Kelly John F.
Published: February 2019

Over the past few years, studies have been conducted exploring the variability in iron nutritional quality from a tropical vegetable, Amaranthus. In order to confirm previous iron bioavailability data, A. cruentus, A. hypochondriacus and A. tricolor lines were grown at the MSU Horticulture Research Center and then analyzed for total and in vitro bioavailable iron. Leaves were harvested 39 days after transplanting, washed, lyophilized and ground. Total iron levels were determined using atomic absorption spectroscopy and bioavailable iron estimates derived using an in vitro assay simulating gastrointestinal digestion. Among the lines tested, total iron concentrations ranged from 145 to 506 ppm. Bioavailable iron ranged from 44 to 70 ppm. Both the total and bioavailable iron measured were highest in A. tricolor, similar to results of previous years. Total iron values were lower for all of the lines than detected previously, but the range of bioavailable iron was similar to earlier work. Bioavailable iron estimated using the in vitro procedure does not appear to be greatly influenced by fluctuations in total iron content. Amaranth could provide between 44 and 70 mg Fe/100 gm fresh weight, equal to 20-35% of the daily Fe requirement for women, and 40-70% for men. Future experiments will utilize an animal bioassay to verify differences detected in bioavailable iron.
220 USING A RESEARCH FACILITY FOR AN EXTENSION OUTREACH PROGRAM FESTIVAL OF COLOR
Authors: Steinegger Donald H.
Published: February 2019

Most of Nebraska's population resides in the urban centers of eastern Nebraska. Traditionally, how ever, the Cooperative Extension Service has catered to the rural populations of the state. Now, it is imperative that the public and the legislative representatives from these urban areas learn that the research and outreach programs of the University also serve them. A Festival of Color was the vehicle for delivering this information to the urban audience, as well as to Agent Educators and Aides, Natural Resource District personnel, and other professionals, including government officials. Both professionals and the general public responded enthusiastically to the Festival's innovative use of the research site.

The educational objective was to answer the public's questions on the environment, including water quality and conservation in the landscape, and reduction of fertilizers and pesticides. Information was presented by Extension Specialists and Assistants, Master Gardeners, Natural Resource- District personnel, Department of Environmental Quality, State Energy Office, and Nebraska Association of Nurserymen.
224 HORTICULTURAL MANAGERS' SEMINAR: UTILIZING EXTENSION RESOURCES IN RESIDENT INSTRUCTION
Authors: Ferguson J.J.
Published: February 2019

The experience and resources of extension specialists can be utilized in resident instruction within a horticultural managers' seminar for advanced undergraduate students, drawing on application of horticultural principles in work situations and other complex issues facing agricultural managers. Guest speakers present an overview of their background, work responsibilities, management philosophy and management practices. Students interact with speakers in this informal seminar and complete written evaluations of speakers and topics for discussion in later classes. This horticultural managers' seminar exposes students to the medley of problems and opportunities facing agricultural managers, utilizes the resources of extension faculty in resident instruction and reinforces ties between commodity departments and their respective industries.
227 HYBRIDIZATION OF THE BRASSICA SELF-INCOMPATIBILITY GENE WITH HAZELNUT
Authors: Hampson Cheryl R. , Azarenko Anita N.
Published: February 2019

Self-incompatibility, a genetic mechanism enforcing out crossing, is most commonly controlled by a single, multi-allelic gene, designated the S-gene. Sporophytic self-incompatibility (SSI), a form of incompatibility determined by the parent plant rather than the gametes, is present in the Brassicaceae, Compositae and other families, and also in hazelnut (Corylus avellana L.). Little is known about the molecular basis of SSI in plants other than crucifers. An S-gene cloned from Brassica oleracea (donated by Dr. June Nasrallah, Cornell University) was used to probe genomic DNA obtained from seven hazelnut genotypes. DNA hybridization was observed in cultivars `Hall's Giant' and `Willamette'. Gene similarity was estimated to be 70-80%.
228 DIVERSITY AND PHYLOGENETIC RELATIONSHIPS OF JUGLANS SPECIES DETERMINED FROM NUCLEAR DNA RFLP ANALYSIS
Authors: Fjellstrom Robert G. , Parfitt Dan E.
Published: February 2019

RFLPs were studied in 41 populations of 13 Juglans species to study genetic diversity and phylogenetic relationships. 19 single locus nuclear RFLP loci were used to generate genetic distance/identity matrices based on allele frequencies. 21 probes were used to generate genetic distances and phylograms using shared-fragments with parsimony analysis. Parsimony analysis on fragment data produced a minimal length tree in general agreement with distance data trees, but with additional phylogenetic resolution resembling previous systematic studies. All analyses indicate an ancient origin of J. regia, which has been considered a recently derived species. A 10x difference in heterozygosity was seen among species. Genetic differentiation among conspecific east Asian populations was larger than among east Asian species. The opposite was true for American species. J. hindsii is classified as a distinct species and J. cinerea was included in section Cardiocaryon rather than Trachycaryon, from the diversity analysis.
232 LINKAGE RELATIONSHIPS OF ISOZYME AND MORPHOLOGICAL MARKERS IN INTERSPECIFIC CROSSES OF CHESTNUT
Authors: Huang Hongwen , Dane Fenny , Norton Joseph D.
Published: February 2019

Linkage relations among eight isozyme genes, Acp-3, Est-1, Est-5, Prx-1, Prx-2, Prx-3, Me and Adh, and two morphological markers, Inh, and Twh, were investigated in one F2 and two BC1 families of interspecific crosses between the American chestnut (Castanea dentata) and the Chinese chestnut (C. mollissima). Inh was found to be consistently linked with Prx-1 and Est-5 in all families. The order of these three genes was determined to be-Ihn--Prx1--Est5. In addition, four other gene pairs, Acp3--Inh, Acp3--Prx1, Me--Inh and Twh--Inh were found to be linked in one of the three families investigated. The four isozyme genes and two morphological marker genes were tentatively integrated into one linkage group with the following gene order Acp3--Me--Twh--Inh--Prx1-Est5. This study demonstrated that isozyme genes can be integrated with morphological marker genes into a single linkage map without the need for additional crosses.
233 USING RAPDs TO INVESTIGATE GENE INTROGRESSION IN APPLE
Authors: Durham Richard E. , Korban Schuyler S.
Published: February 2019

DNA was extracted from leaves of various Malus genotypes and used to screen synthetic decamer oligonucleotide primers. Samples from the following two groups were bulked: 1) seven scab-susceptible apple cultivars, and 2) 15 scab-resistant apple genotypes derived by introgressive hybridization from the previous group of cultivars. A third sample consisted of DNA extracted from Malus floribunda Sieb. clone 821, the original source of apple scab resistance for all genotypes in the second group. A total of 59 primers from kits A, L, and R (Operon Technologies) were screened. Amplified fragments were obtained for 93% of the primers tested, while random amplified polymorphic DNA (RAPD) fragments were detected among samples for 76% of the primers. One primer, A15, amplified a unique band in both M. floribunda clone 821 and the bulked scab-resistant sample. This RAPD marker, designated OA15900, identifies an amplified, introgressed fragment that likely corresponds to a region of the genome that may serve as a modifier for the scab resistance gene block V, derived from M. floribunda clone 821.
247 SOMATIC HYBRIDIZATION BETWEEN SOLANUM OCHRANTHUM AND LYCOPERSICON ESCULENTUM
Authors: Kobayashi Ruth S. , Sinden Stephen L. , Stommel John R.
Published: February 2019

Incorporation of genes from wild species has been a major contributor to tomato improvement in recent years. Solanum ochranthum, a woody non-tuber bearing species, is a potential source of resistance against tomato diseases and insect pests but is genetically isolated from tomato. Somatic hybridization methods were developed to facilitate the use of S. ochranthum for tomato germplasm improvement. Leaf mesophyll protoplasts of S. ochranthum and a Lycopersicon esculentum hybrid were chemically fused with polyethylene glycol. The protoplasts were initially cultured in Shepard's CL, a MS based medium, containing 1 mg·1-1 NAA, 0.5 mg·1-1 BAP and 0.5 mg·1-1 2,4-D. Hybrid regenerants and regenerants of the L. esculentum parent were recovered; S. ochranthum did not regenerate. Hybridity was established by morphological characters, peroxidase isozyme and RAPD markers. Use of these somatic hybrids for tomato improvement was evaluated.
250 INDUCTION AND AVOIDANCE OF VITRIFICATION OF MICROPROPAGATED ONION (ALLIUM CEPA L.)
Authors: Schloupt Renee M. , Splittstoesser Walter E. , Skirvin Robert M.
Published: February 2019

The objective of this research was to induce vitrification in onion (Allium cepa L. cv. `White Ebeneezer'); then use this information to make suggestions on how to avoid vitrification of micropropagated plants. There were no differences in vitrification percentage when shoot tip explants were isolated, sterilized and placed on MS medium (8 g.L-1 agar) supplemented with 0.16 uM NAA and varying (0.0 to 70.0 uM) levels of BA. When agar was replaced by gelrite (MS medium with 4.4 uM BA and 0.16 uM NAA), vitrification increased when gelrite concentrations decreased from 2.0 to 1.0 g.L-1. More vitrification occurred when shoot tips were supported on a synthetic cosmetic puff in liquid medium or when agar was reduced to 4.0 g.L-1 than when supported on a cosmetic puff in 8 g.L-1 agar or on 8 g.L-1 agar alone.
256 THE EFFECT OF VARYING THE N:S BALANCE IN POINSETTIA ON PLANT COLOR RESPONSE AND CONSUMER APPEAL
Authors: Adams Stacy A. , Paparozzi Ellen T.
Published: February 2019

Nitrogen and sulfur are macronutrients required by plants to form amino acids used in protein synthesis and other metabolic processes. Commercial poinsettia nutrient recommendations suggest N levels of 350-400 ppm later reduced to 200-250 ppm N. Previous hydroponic research determined that N may be reduced by half if supplied S levels are adequate. The purpose of this study was to look at multiple N and S levels and gauge the effects these combinations had on plant quality.

Poinsettia cv. `Dark Red Hegg' plants, grown in a soilless mix, were fertilized with 56 N and S combinations. N was supplied from 100-275 ppm and S from 0-75 ppm. Plants were evaluated quantitatively by chroma meter readings every three weeks and qualitatively by marketability evaluations from commercial producers, retailers, and consumers.

Results indicate 0 ppm S plant color was more yellow-green than all others. Plants were greener as N increased from 100-150 ppm with no difference above 175 ppm. Evaluators identified plants receiving 0 ppm S and 100 or 125 ppm N as unmarketable. N may be reduced to 175 ppm with no effect on plant quality if adequate S is applied.
265 SPRING NITROGEN UPTAKE, ALLOCATION, AND LEACHING LOSS OF CITRUS IN A SANDY SOIL
Authors: Lea-Cox John D. , Syvertsen James P.
Published: February 2019

Eighteen, 4-year-old Grapefruit (Citrus paradisi) cv. `Redblush' trees on either Volkamer lemon (C. volkameriana = VL) or Sour orange (C. aurantium = SO) rootstocks were grown in 7.6 kiloliter drainage lysimeters in a Candler fine sand (Typic Quartzipsamments), and fertilized with nitrogen (N) in 40 split applications at 76, 140 and 336 g N year-1 (= 0.2, 0.4 and 0.9 x the recommended annual rate). Labelled 15N was substituted for the N in a single fertigation at each rate at the time of fruit set the following year, to determine N uptake, allocation and leaching losses. “Nitrogen-uptake and allocation were primarily determined by the sink demand of fruit and vegetative growth, which in turn were strongly influenced by rootstock species. Larger trees on VL required at least 336 g N yr-1 to maintain high growth rates whereas smaller trees on SO of the same age only required 140 g N year-1. Of the 15N applied at the 336 g N rate to the SO trees, 39% still remained in the soil profile after 29 days. With optimally scheduled irrigations, 15N leached below the root zone was less than 3% of that applied after 29 days, regardless of rate. However, 17% of the applied 15N was recovered from a blank (no tree) lysimeter tank. Total 15N recovery ranged from 55-84% of that applied, indicating that a sizeable fraction of the 15N applied may have been lost through denitrification.
277 ANTICOAGULANT ACTIVITY OF ALLIUM ACCESSIONS
Authors: Goldman I.L. , Schwartz B.R
Published: February 2019

In the past twenty years, the presence of blood anticoagulants in plants has been confirmed by a range of clinical and in vitro investigations. The presence of anti-clotting factors in plants presents a unique opportunity for dietary enhancement of circularion and fibrinolysis. Experiments were conducted to assess variability in anticoagulant activity of a range of Allium wild species and cultivated accessions. Anticoagulant activity was determined via a platelet aggregation assay with human plasma. Extracts were prepared from 19 Allium species accessions and 24 cultivated accessions of Allium cepa, including standard inbred lines and open-pollinated popularions. Relative inhibition of platelet aggregation was measured for each accession and inhibition constants (IC50) were calculated. Data from this investigation dcmonstrate large IC50 variability among accessions. Larger IC50 differences (up to 45-fold) were measured among A. cepa accessions than among Allium species accessions (up to 16-fold). Yellow storagc-type A. cepa accessions exhibited the strongest inhibitory activity. Implications of these findings to onion breeding and platelet function will be presented.
278 GENETIC VARIABILITY FOR PRECOCIOUS PALM HEART YIELD OF PEJIBAYE IN HAWAII
Authors: Clement Charles R. , Manshardt Richard M.
Published: February 2019

The pejibaye (Bactris gasipaes, Palmae) is being evaluated in Hawaii as a source of fresh hearts of palm. Nine open-pollinated progenies from the Benjamin Constant population of the Putumayo landrace are planted at three sites in a RCB. The best site started yielding at 15 months after planting, the intermediate at 16 months, the poorest at 18 months. During the first four months of harvest at the best site, 25% of the plants were cut; during three months at the intermediate site, 15% were cut; during the first cut at the poor site, 1% were cut. Progeny harvest percentages ranged from 7 to 53% at the best site, with only three progenies above average (33, 47, 53%). These are considered to be precocious. These three progenies produced average size hearts (172±36, 204±57, 203±44 g/plant, respectively; experimental mean±SD = 205±53 g), but yielded above average at 5000 plants/ha (275, 480, 524 kg/ha, respectively; exp. mean = 272 kg; corrected for % cut). Potential yields of these progenies were near the mean (871±198, 1018±280, 983±197 kg/ha, respectively; exp. mean = 986±381 kg/ha), but their precocity provides early returns to the farmer.
288 STUDY OF THE ALLELOPATHIC PROPERTIES OF LYCOPERSICON HIRSUTUM
Authors: Bish Eric B. , Bewick Thomas A. , Shilling Donn G.
Published: February 2019

Laboratory experiments were conducted to evaluate the relationship between leaf area, leaf number, dry weight, and mg extract of Lycopersicon hirsutum (LA 1777) leaf washes and germination or root growth of common purslane (Portulaca oleracea) seeds. Additional experiments were conducted to determine the relationship between L. hirsutum (accessions 1777 and 1625) leaf washes and germination or root growth of common purslane seeds. Activity of separated sesquiterpenes from trichomes were compared to crude leaf washes. Results from the leaf washes of the L. hirsutum accessions (1777 and 1625) indicated that there was no significant difference between hexane leaf washes, methanol leaf washes, or crude leaf extracts when common purslane was used as the assay species. The accession 1777 was greater than 800 x more inhibitory to germination and greater than 300x more inhibitory to root growth of purslane seeds than accession 1625.
292 WAX PLATELET ARRANGEMENT, GA4+7 APPLICATIONS, AND THEIR RELATIONSHIPS TO RUSSET IN `HARALSON' APPLES
Authors: Foulk Doug S. , Hoover Emily E.
Published: February 2019

`Haralson,' the most widely-grown cultivar in Minnesota, is highly susceptible to russetting and cracking in many orchards. Because wax platelet arrangement has been proposed as a cause for russettting in `Golden Delicious' apples, we examined the wax platelet arrangement of `Haralson' apples. When compared to the wax platelet arrangement found on the russet-susceptible `Golden Delicious,' and on `McIntosh,' a cultivar which does not russet in our region, `Haralson' platelets were large and upright in orientation, more numerous than found on `Golden Delicious,' but unlike the smaller, more granular platelets found on `McIntosh.' In a concurrent study, we made four GA,,, (Provide) applications, at petal fall and at p.f. +10, 20, and 30 days. At harvest, the treated and untreated blocks of trees were examined for incidence of russet, 25-ct. wt., and total yield per tree. Treated trees produced a greater number of fruit of slightly larger size and with reduced incidence of russet than untreated trees in the study.
308 IMMUNOLOCALIZATION AND GENE CLONING OF ZEATIN OXYLOSYLTRANSFERASE
Authors: Martin Ruth C. , Mok Machteld C. , Mok David W.S.
Published: February 2019

Cytokinins are widely used in tissue culture and transformation systems; however, little is known of their mode of action or the mechanisms regulating their levels in plant tissues. We are studying enzymes responsible for the metabolism of zeatin in immature seeds of Phaseolus. Selective expression of genes encoding such enzymes may regulate the level of active cytokinins during seed development as well as in in vitro systems. A zeatin O-xylosyltransferase, which mediates the formation of O-xylosylzeatin from trans-zeatin and UDP-xylose, has been isolated and monoclonal antibodies specific to the enzyme have been produced. Tissue print analyses demonstrated that the enzyme is primarily localized in the endosperm. ln situ localization and EM studies indicated that the enzyme is present in the cytoplasm and the nucleus. cDNA libraries were constructed from immature seed mRNA and immunopositive clones were selected. The products of these clones are being analyzed in E. coli and baculovirus expression systems.
326 IMBIBITION IN SUGARS AND DEHYDRATION ALLOW STRAWBERRY PLANTLETS TO SURVIVE CRYOPRESERVATION
Authors: Seufferheld Manfredo J. , Stushnoff Cecil
Published: February 2019

Strawberry plantlets, regenerated from leaf disks, were used as a model system to study the effect of high concentrations of sugars and dehydration on survival during cryopreservation. After cold acclimation, plantlets imbibed for 3 days (one day each) in 0.5, 0.7 and 1.2 M sucrose and (1.0M sucrose + 0.2M raffinose) and desiccated to 25 % moisture (fwb) in alginate capsules consistently survived cryopreservation. Differential scanning calorimetry revealed only a very small exotherm between -20C and -28C during freezing; a glass transition at -50C and a small melting event at -10C during warming. Conversely, samples with the lowest survival rate, had a large nucleation exotherm at -30C and a devitrification exotherm between -70 and -40C. We conclude that imbibition with sugars, coupled with desiccation treatments, may be used to manipulate freeze tender tissues of strawberry to permit successful cryopreservation.
338 CONSTRUCTION OF A GENETIC LINKAGE MAP AND LOCATIONS OF COMMON BLIGHT RESISTANCE LOCI AND RUST ADULT RESISTANCE IN PHASEOLUS VULGARIS L USING RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) MARKERS
Authors: Jung Geunhwa , Coyne Dermot P. , Arnaud-Santana E. , Bokosi James , Kaeppler Shawn M. , Skroch Paul W. , Nienhuis James
Published: February 2019

Common bacterial blight(CBB) and rust diseases, incited by the bacterial pathogen Xanthomonas campestris pv. phaseoli (Smith) Dye (Xcp) and Uromyces appendiculatus, respectively, are important diseases of common beans (Phaseolus vulgaris L.). The objectives were to construct a molecular linkage map, to locate CBB resistances, rust resistances and leaf pubescence using RAPDs. Sixteen linkage groups with 22 unassigned markers were identified. 178 RAPD markers and 8 morphological markers were mapped in a Population of 70 RI lines. Regression analysis and interval mapping using MAPMAKER/QTL were used to identify genomic regions involved in the genetic control of the traits. One, two, and three putative QTLs were identified for seed, pod and leaf reactions. These regions accounted for 18%, 25%, and 35% of the phenotypic variation in CBB resistance. A chromosome region on linkage group 1 carried factors influencing all three traits. Rust resistance genes controlling the reactions on the primary and on the 4th trifoliolate leaves (adult plant resistance) were located in linkage group 16. The genes for abaxial leaf pubescence was located on linkage group 9.
344 PRETRANSPLANT NUTRIENT CONDITIONING: NITROGEN REGIMES FOR FLORIDA TOMATO TRANSPLANTS
Authors: Vavrina Charles S. , Hochmuth George
Published: February 2019

`Allstar” tomatoes raised from seed in Todd™ containerized transplant trays were treated with 1/4 strength Hoagland's solution modified to supply 0, 15, 30, 45, 60, or 75 mg·l-1 N daily. Nutrient application was achieved via ebb and flow irrigation. N was supplied as ammonium nitrate. Tissue sample values for elements tested, excluding N, were essentially adequate for all treatments at transplanting (6 weeks after seeding). Visible transplant differences in the plant house did not translate to significant yield differences in the field when rates of 30 mg·l-1 or greater were used in either spring or fall plantings in FL. A similar trial shipped to PA showed that 75 mg·l-1 in the plant house resulted in the greatest early field yields, but 45 mg·l-1 produced the greatest overall yield.
345 DIFFERENTIAL GROWTH INHIBITION OF BRASSICA SPECIES BY BROCCOLI RESIDUES
Authors: Santos Jose R.A. , Leskovar Daniel I.
Published: February 2019

Poor seedling emergence and stunted growth were observed in cauliflower (Brassica oleracea L., Botrytis group) and cabbage (Brassica oleracea L., Capitata group) crops when planted after three consecutive monocrops of broccoli (Brassica oleracea L., Italica group). This study was conducted to assess seed, seedling, and plant growth responses of broccoli, cabbage, and cauliflower to broccoli residue (leaves, stem + roots, and whole plant) extracts, broccoli residue incorporation, or soil previously cropped to broccoli. Osmotic potential, electrical conductivity, and pH of extracts were measured, rate (T50) and total germination were determined. Filter-sterilized leaf extract delayed T50(7.5 d) and reduced total germination (22%) of cauliflower compared to broccoli or cabbage. Similarly, plant height, shoot dry weight, and leaf area of cauliflower were significantly reduced when grown on broccoli soil in the greenhouse. Cabbage and cauliflower had low total marketable yields with more culled heads when grown in the field previously cropped to broccoli. Therefore, a potential growth inhibition of cabbage and cauliflower exists when following a continous cropping of broccoli.
349 PROTEINS IN CHRYSANTHEMUM AS AN INDICATOR OF FLOWER LONGEVITY
Authors: Williams Michelle H. , Nell Terril A. , Barrett James E.
Published: February 2019

It is generally accepted that ethylene production is centrally located in petal senescence, however, non-climacteric flowers senesce irrespective of the presence of ethylene. The regulation of flower senescence may well be linked to protein synthesis. Our objective was to develop a simple tool which can be used in breeding programmes and\or the market place to determine potential longevity of a flower. Here, SDS-PAGE protein profiles of both potted and cut chrysanthemum flowers were determined from flowering to senescence. Generally, only minor changes in both protein content and the proportion of the major polypeptides were observed in the potted flowers. However, polypeptides at 40, 45 and 65 kDa increased during flower senescence and are of particular interest because they could be linked to flower longevity. The apparent stability of the proteins may contribute to the long postharvest life of the potted chrysanthemum.
356 ROOT AND SHOOT GROWTH PERIODICITY OF GREEN ASH, SCARLET OAK, TURKISH HAZELNUT AND TREE LILAC
Authors: Harris J. Roger , Bassuk Nina L. , Zobel Richard W. , Whitlow Thomas H.
Published: February 2019

Root and shoot growth periodicity were determined for Fraxinus pennsylvanica Marsh. (green ash), Quercus coccinea Muenchh.,Corylus colurna L. (Turkish hazehut) and Syriaga reticulara (Blume) Hara `Ivory Silk' (tree lilac) trees. Two methods for determining root growth periodicity using a rhizotron were evaluated. One method measured the extension rate of individual roots, and the second method measured change in root length density. A third method, using periodic counts of new roots present on minirhizotrons, was also evaluated. The root extension method showed the least variability among individual trees. Shoot growth began before or simultaneously with the beginning of root growth for all species with all root growth measurement methods. Species with similar shoot phenologies had similar root phenologies when root growth was measured by the root extension method, but not when root growth was measured by the other methods. All species had concurrent shoot and root growth, and no distinct alternating growth patterns were evident when root growth was measured with the root extension method. Alternating root and shoot growth was evident, however, when root growth was measured by the other methods.
357 PHOTOSYNTHETIC RESPONSE OF SELECT RED MAPLE CULTIVARS TO LIGHT INTENSITY
Authors: Sibley Jeff L. , Eakes D. Joseph , Gilliam Charles H. , Dozier William A.
Published: February 2019

Net photosynthesis (Pn), stomatal conductance (Cs), transpiration (Ts), and water use efficiency (WUE) were determined with a LICOR 6250 Portable Photosynthesis System for four cultivars of Acer rubrum L. under light intensities ranging from 300 to 1950 μmol·m-2·sec-1 photosynthetically active radiation (PAR). As PAR increased, there was a linear relationship for Pn, Cs, and Ts for the cultivars `Franksred' (Red Sunset TM) and `October Glory'. In contrast, the cultivars `Schlesingeri' and `Northwood' had quadratic relationships for Pn and Cs as PAR increased. Ts was quadratic for `Schlesingeri' and had a linear relationship for `Northwood.' WUE was quadratic for each of the four cultivars.
377 EVOLUTION OF GREENHOUSE MANAGEMENT COURSES
Authors: Stack Lois Berg
Published: February 2019

Information presented in greenhouse management courses has changed in response to several factors. Increasingly, students must learn about:

new technologies such as the use of computers in crop management, and new techniques such as implementation of biological pest management;

regulations like the EPA/OSHA chemical safety laws;

experimental procedures, to be able to assess future technologies and techniques during their careers; and

professionalism (industry leadership, ability to work with the media, knowledge of how to impact law).

Changes in course content and procedures over time, and methods of teaching increased types and amounts of information, are discussed through results of a survey of current instructors of greenhouse management courses.
381 THE SFASU ARBORETUM: A CONSERVATION STRATEGY FOR THE ENDANGERED PLANTS OF EAST TEXAS
Authors: Creech D. L. , Singhurst J.
Published: February 2019

The Stephen F. Austin State University Arboretum occupies ten acres of campus property on the banks of LaNana creek, the stream that bisects the campus and the city of Nacogdoches, the oldest town in Texas. The mission statement of the Arboretum is to promote the conservation, selection and use of the native plants of east Texas. There are 19 species in east Texas that are either federally endangered, state endangered, or in danger of extirpation from the state. Many others face a serious decline in numbers as appropriate habitats diminish. A long-term project of ex situ and in situ conservation was initiated in 1992. Goals include: 1) acquire global position and vegetative analyses of endangered plant communities, 2) utilize ArcCAD® (a PC-GIS software) to archive a collection of maps, photographs, plant community data, and text, 3) maintain an ex situ collection of endangered plants from known provenances in the arboretum, and 4) reintroduction of species into appropriate protected habitats. The project involves the cooperation of several state and federal agencies and integrates the resources of a university horticulture program with the needs of endangered plant conservation.
393 ONE COOLER, SINGLE TEMPERATURE COOLING OF POTTED TULIPS
Authors: Dole John M.
Published: February 2019

`Blenda', `Leen v.d. Mark', `Monte Carlo', `Negritta' and `Paul Richter' tulip (Tulipa gesneriana) bulbs received a total of 15 weeks of cold (5°C) with 0, 2, 4, 6, 8, 10, or 12 weeks applied to dry, unpotted bulbs. The bulbs were then planted, watered, and exposed to cold for the remainder of the 15 weeks. Bulbs receiving up to 10 weeks dry, unpotted cold showed no decrease in flowering percentage and plant quality when compared to bulbs receiving 15 weeks of moist, potted cold. For bulbs receiving 12 weeks of dry cold, flowering percentage was generally lower when compared with 0-10 weeks of dry cold and varied with the cultivar and the year, i.e. 63% of `Paul Richter' and 100% of `Negritta' bulbs receiving 12 weeks of dry cold flowered in year one: whereas, 95% of `Paul Richter' and 70% of `Negritta' bulbs flowered in year two. For all cultivars, bulbs receiving 12 weeks of dry cold had the shortest shoots at the end of the cooling treatment compared with the other treatments. While final height varied significantly with the cultivar in year two, differences were not commercially noticeable. Final height was not influenced in year one.
404 PB 013 JOB ANALYSIS OF THE LANDSCAPE INDUSTRY IN ARIZONA
Authors: Tipton Jimmy L.
Published: February 2019

The Arizona Certified Landscape Professional conducts educational programs and certification exams to increase the knowledge and skills of landscapers. To ensure that the program accurately reflects industry needs, we conducted a job analysis survey. Over 100 individuals in 48 landscape organizations responded. Two-thirds of the organizations were `for profit' as opposed to municipal parks departments, school districts, and resorts. Half the `for profit' organizations were small with gross receipts of less than $100,000 annually. Forty percent of the `for profit' organizations were devoted exclusively to landscape maintenance, 28 percent were restricted to installation, and the remainder did both installation and maintenance. Size and nature (`for profit' or `in house') of the organization had a significant impact on tasks and responsibilities of employees. These data will be used to modify the educational programs and certification exams to more closely resemble day-to-day activities among landscapers in Arizona.
406 PB 019 DEVELOPMENT OF AN INTEGRATED LOCATION AND INFORMATION DATABASE FOR TEACHING CAMPUS PLANT MATERIALS
Authors: Beyl Caula A. , Sabota Cathy , Ghale Gokul
Published: February 2019

In teaching a course in landscape plant materials, the landscape plants which exist on campus are an important and accessible resource. Management of location, health. and cultivar information is critical to optimizing this resource. As a classroom assignment, campus plant materials were inventoried, entered into FileMaker Pro 2.1, a database manager, characterized and assigned locations. The campus map was scanned using a Microtek ScanMaker IIXE and the image imported into MacDraw II. A symbol library, which included symbols for trees, shrubs, and groundcovers, was developed by scanning hand drawn images and then importing them into MacPain. These bit-mapped images could then be duplicated as often as necessary and placed in appropriate locations on the campus map in MacDraw II. In this way, students are exposed not only to landscape plant materials but also to database managers and computer graphics capabilities. This approach also has the advantage that database information can be easily coordinated with physical location. plant materials can be sorted based on their characteristics, and information can be routinely and easily revised and updated.
410 PB 051 SUPPORTING THE FARMER'S BOOKSHELF™ CROP INFORMATION SYSTEM ON TWO COMPUTER PLATFORMS
Authors: Kobayashi Kent D. , Bittenbender H.C.
Published: February 2019

Extension personnel and growers need up-to-date information on crops to make sound management decisions. The Farmer's Bookshelf™, a hypermedia information system based on the software HyperCard®, was developed for Macintosh® computers. Since clientele who use IBM-compatible computers could not use the Macintosh version of the Farmer's Bookshelf, we looked into several DOS/Windows™ hypermedia software. Spinnaker PLUS™ (Spinnaker Software Corp.) suited our needs, primarily because it required a minimum of reprogramming. PLUS (Macintosh) converted HyperCard files into PLUS (Macintosh) files. Some programming, fonts, and icons required modifications. PLUS (Macintosh) files were then edited using PLUS (widows). Again, minor editing was necessary. Currently, the PLUS (Windows) files and a runtime version of PLUS (Windows) are distributed to clientele who use IBM-compatible computers. PLUS enables our supporting the Fanner's Bookshelf without having to develop a DOS or Windows version that requires completely new programming and extensive modifications. HyperCard files are readily converted to run under Windows, thus helping us to serve clientele who use either platform.
418 PB 095 WHOLE FARM CASE STUDIES OF HORTICULTURAL PRODUCERS IN WESTERN OREGON AND WASHINGTON
Authors: Murray Helene , Dick Richard P. , Green-McGrath Daniel , Lev Larry S.
Published: February 2019

Calls for increased farmer involvement in research and extension programs have been numerous and well supported. One approach to integrate the collective knowledge and experience of scientists and farmers is through whole farm case studies (WFCS). An interdisciplinary team of 34 research and extension personnel at Oregon and Washington State Universities conducted WFCS of 16 vegetable and small fruit farms.

The WFCS process proved useful in developing an interdisciplinary team, and the vast majority of team members stated they would consider using the WFCS approach again; but the primary constraint cited was the amount of time required. Team members gained a better understanding of the complexity of farms and identified areas requiring further research. Farmers stated they enjoyed participating and discovered new information that will assist them in managing their fanning systems. Farmer-developed innovations were identified that are useful to other farmers and to the research process.
420A PB 135 A COMPARISON OF INTERACTIVE MULTIMEDIA INSTRUCTION WITH TRADITIONAL INSTRUCTION IN POST-SECONDARY PLANT MATERIALS COURSES
Authors: Zampardo Mark , Kling Gary , Lindsey Christopher
Published: February 2019

An integrated teaching system was developed to enhance retention of course material covered in a woody landscape plants identification course. A Toolbook-based software program which incorporates high quality digital images and text in an interactive computer environment was tested on groups of randomly selected plant materials students. The objectives of the project were to: increase use of visual study techniques, facilitate individualized instruction, increase student access to information that is often not available in the classroom or from standard references, and enhance retention of course material. In alternating 4-week periods of time, one half of the students in the class had password access to the software. All students continued to receive traditional lecture and laboratory presentations of the material. This study was conducted with a pretest-posttest control group experimental design. Students' written test scores, performance on identification exams and student opinions were compared between the two groups.
421 PB 124 GROWTH AND NUTRIENT DYNAMICS IN ILEX CRENATA THUNB. `HELLERI' ACROSS AN ALUMINUM GRADIENT
Authors: Lasseigne F. Todd , Smalley Timothy J. , Mills Harry A. , Miller William P.
Published: February 2019

Ilex crenata `Helleri' (Helleri holly) can experience landscape establishment problems in the Southeast. Since aluminum toxicity is a major problem in acid soils of the Southeast, this experiment studied the effects of aluminum on Helleri holly grown in solution culture. A modified Hoagland's solution contained low phosphorus concentrations (32 μM), a 1:1 NH4+:NO3- nitrogen ratio, and aluminum treatments consisting of 0, 222, 444, 889, and 1332 μM Al supplied at equal ratios from AlCl3·6H2O and Al2(SO4)3·18H2O. The MINTEQA2 (version 3.11) chemical speciation model was used to predict activity of ions in solution. Shoot growth and root length were not affected by aluminum after 12 weeks in solution culture. Total plant nutrient uptake was monitored weekly. Results indicate that Helleri holly does not take up aluminum ions even though NH4+ is the preferred nitrogen source. Other studies have shown increased aluminum toxicity effects when NH4+ is the preferred nitrogen source.
426 PB 139 NITROGEN UPTAKE AND DISTRIBUTION IN RED OAKS AND RED MAPLES
Authors: Larimer Jill C. , Struve Dan
Published: February 2019

In the spring of 1993, red oaks (Quercus rubra) and `Red Sunset' red maples (Acer rubrum cv. `Red Sunset') were propagated from seed and microcuttings, respectfully. From June through October, plants were fertilized twice daily with 1.4 liters of fertilizer solution at concentrations of 0, 25, 50, 100, 200, or 400 ppm nitrogen from a 20-10-20 water soluble fertilizer. Destructive harvests were conducted six times at intervals from June through December. Leaf area, stem height, root length, root area, and dry weights of roots, stem, and leaves of harvested plants were measured and tissue nutrient concentration analyzed. Nutrient analyses of roots, stems, and leaves show seasonal distribution patterns of nitrogen. Dose- response patterns of fertilizer rate and growth were identified throughout the growing season.
430 PB 171 LEAF NITRATE AND AMMONIUM CONCENTRATIONS ARE MORE SENSITIVE INDICATORS OF SOIL N AVAILABILITY THAN TOTAL N IN NECTARINE
Authors: Rubio Oswaldo A. , Brown Patrick H. , Weinbaum Steven A.
Published: February 2019

Leaf N concentrations (% dry wt) appear relatively insensitive to high levels of applied fertilizer N (Weinbaum et al, HortTechnology 1992). This insensitivity may be attributable to growth dilation, lack of additional tree N uptake, a finite capacity of leaves to accumulate additional N or our inhability to resolve a limited increment. Our objective was to asses the relative accumulation of mobile forms of N (NO3, NH4 and amino acids) relative to a total N over a range of fertilizer N application rates in 3 year old, field-grown “Fantasia” nectarine trees. Between 0 and 136 Kg N/Ha/Yr we observed a linear relationship between N supply and all N fractions. Above 136 Kg N/Ha/Yr leaf concentrations of amino acids and total N remined constant, but NO3 and NH4 accumulation continued. These results suggest that leaf concentration of NO3 and NH4 are more sensitive indicators of soil N availability and tree N uptake than was total leaf N concentration.
437 PB 212 EFFECT OF SOIL FUMIGATION WITH METHYL BROMIDE ON MINERAL NUTRITION OF STRAWBERRY
Authors: Ragab M.E. , Okasha Kh. A.
Published: February 2019

This study was earned out on strawberry (Fragana × ananassa, Duch.) during the tow successive season of 1988/1989 and 1989/1990, at the strawberry Improvement Center Experimental Farm at Omm saber, south Tahreer, El Behira Governorate. The objective of this work was to study the effect of strawberry cultivar Douglas A split-plot design with four replicates was adopted. The results indicated a substantial increase in the content of the available macro and micro nutrients in the fumigated soils compared to the non fumigated ones. A significant increase in the number of leaves per plant, fresh and dry weight, early and total yield per plant was recorded. Fumigation accompanied by fertilization increased the available content (N,P and K and (Fe, Mn, Zn, and Cu) in the soil in the both growing seasons compared to fumigated only or the control. Plants grown in the fumigated fertilized plots contained the highest amount of macro and macro nutrients in both the growing seasons. Fumigated non fertilized plots had the highest amount of available P and K than all other treatment The maximum early and total yield per plant was obtained from the fumigated non fertilized plots.
438 PB 215 RISK OF GENE MUTATION IN MAJOR CROPS
Authors: Pollock Bruce M.
Published: February 2019

The book, Agricultural Biotechnology: Issues and Choices Information for decision Makers, from USDA and Land Grant Colleges discusses risk evaluation for the use of legislators concerned with public policy. However, that discussion is entirely theoretical. The 1970 epidemic of Southern Corn Leaf Blight caused by the pleiotropic gene for Cytoplasmic Male Sterility provides material to use in real-world risk evaluation for biotechnology. Approximately 1×1012 corn seeds are planted annually in the US. Assuming a mutation rate of 1×10-6, then 1×106 mutations can be expected annually. The poster will evaluate the importance of this number using assumptions based on fold-increase during seed production. Unfortunately, it is not possible to evaluate the risk of incorporating another pleiotropic gene into commercial crops because insufficient data are available on the frequency of pleiotropy.
439 PB 218 CHROMOSOMAL VARIATION AMONG PROGENY OF FACULTATIVE APOMICTIC GUAYULE
Authors: Ray Dennis T. , Cho Youngkoo
Published: February 2019

Progress toward the domestication of guayule (Parrhenium argentatum Gray) as a domestic source of latex, has been slowed because of its complicated reproductive biology. This work was performed to help elucidate the facultative nature of apomictic reproduction in guayule. Ploidy level and six morphological characters were measured in one-hundred and eighty open-pollinated, half-sib progeny derived from twelve different apomictic tetraploid (4n=4x=72) female parents. The number of chromosomes observed among the half-sib progeny varied from 36 to 81, with the majority (77.3%) of the progeny with 72 chromosomes. All of the observed chromosome numbers could be explained either by meiotic reduction in the megaspore mother cells or fertilization of egg cells or both. The frequencies of meiotic reduction and fertilization resulting in these progeny were estimated to be 27.2 and 22.7%, respectively. Among the six measured morphological characters, significant correlations were found only between chromosome numbers and plant height (r=0.37) and leaf area (r=0.31).
441 PB 244 CULTURE OF ISOLATED EMBRYOS OF DETERIORATED MAIZE SEED: A STRATEGY FOR RESCUING GERMPLASM
Authors: Blackman Sheila A. , Roos Eric E.
Published: February 2019

The low quality of some seed lots received by germplasm repositories such as the National Seed Storage Laboratory can thwart efforts to regenerate seed for storage. This germplasm is in danger of irretrievable loss. The aim of this work is to promote the germination, and hence regeneration, of such low quality seeds through sterile culture of the isolated embryos. Hybrid (B73×LH51) maize seeds were aged 5 y at 32°C and 0.037 g H2O g-1 dry wt. Vigor - but not viability -declined under these conditions. The effects of four factors on growth and germination were systematically examined. These were: seed pretreatments; antibiotics and fungicides; nutrients; and growth substances. Amongst the pretreatments, none surpassed partial hydration of seeds for 24 hr to 0.55 g H2O g-1 dry wt at 25°C prior to embryo dissection. Thiram (2.4 mg mL-1) and kanamycin (50 ug ml1) effectively controlled bacterial and fungal growth with no deleterious effects on growth during culture of the isolated embryos. Exogenous sucrose (optimum 5 % wt/vol) significantly stimulated radicle growth in both deteriorated and non-deteriorated embryos. No other organic or inorganic nutrient stimulated growth. Naphthalene acetic acid did not affect growth while kinetin reduced radicle growth and stimulated coleoptile growth. Gibberellic acid (GA3 at 10-5M) significantly stimulated radicle growth in deteriorated embryos, whereas it promoted coleoptile growth in both deteriorated and non-deteriorated embryos. These data suggest GA or a GA-stimulated process may limit the growth of aged embryos.
465 PB 324 QTL MAPPING AND MARKER-ASSISTED SELECTIONUSING INDEPENDENTLY GENERATED INBRED BACKCROSS TOMATO POPULATIONS
Authors: Triano Steven R. , St. Clair Dina A.
Published: February 2019

The inbred backcross (IBC) breeding method is being used to introgress genes controlling high fruit soluble solids from a wild tomato species (Lycopersicon cheesmanii f. minor) into a California processing tomato cultivar (Lycopersicon esculentum cv. UC204B). One IBC tomato population (i.e. P1: 106 lines) is being used to map quantitative trail loci (QTL) for soluble solids and other traits. A genetically related but independently generated IBC population (i.e. P2: 96 lines) is being used to lest the efficiency of QTL-linked RPLPs for indirect marker-assisted selection (MAS) to improve soluble solids. P1 was analyzed for fruit quality traits in a replicated field design over 2 years. Twelve P1 lines were significantly greater than UC204B for soluble solids and also had acceptable fruit weights and horticultural traits. All twelve lines have been publicly released for further breeding efforts. In P1. we have identified RPLP markers that have significant correlations to QTL. Some of these markers map to regions previously reported by other researchers to contain QTL for the same traits. We will use 70-80 markers spaced approximately 10-20 cM apart across the genome to screen PI and map QTL. The RPLP analyses are currently in progress. P2 was replicated for one year using the same field design as P1. and analyzed for the same traits. P2 will be screened with QTL-linked RFLPs identified in P1 to test the consistency of QTL locations between independently derived populations. P2 lines selected using RFLP data will be compared to P2 lines identified by classical selection indices. This will indicate if MAS for QTL is effective in a population (P2) genetically independent from the mapping population (P1).