bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature and Seed Moisture Govern Germination and Storage of Gerbera Seed
Authors: Carpenter William J. , Ostmark Eric R. , Cornell John A.
Published: February 2019

Temperature, relative humidity (RH), desiccation, and hydration affect gerbera (Gerbera jamesonii H Bolus ex Hook.f.) seed storage and germination. Germination percentages (G) were maximal and about equal at constant 15, 20, or 25C in darkness or light but lower at alternating temperatures having the same mean temperature. The number of days to 50% final germination (T50) and between 10% and 90% germination (T90 – T10) required the fewest days at constant 25 or 30C; longer germination periods resulted with alternating temperatures. Reducing seed moisture from 7.1% to 3.5% had no effect on G, T50, or T90 – T10 values, but at seed moisture levels <3.5%, G was lower and T50 and T90 – T10 longer. Germination percentages were similar after seed storage from 5 to –5C, but G was lower after storage at –10C or lower. Low-temperature seed storage had no effect on T50 or T90 – T10 values. Seeds had highest G and lowest T50 and T90 – T10 values when germinated at 52% seed moisture, with large declines and delays in germination at lower and higher moisture levels. Seed storage for 12 months without reduction in germination was possible at 5C and 11% or 32% RH. Seeds stored at 52% RH lost G at all temperatures, and no seed germinated after storage at 75% RH and 15 or 25C. Seed stored at 5 or 15C and 11% to 32% RH had the fewest days to T50 and T90 – T10.
MICROPROPAGATION OF ACONZTUM UNCINATUM: GROWTH REGULATOR AND ANTIOXIDANT SCREENING USING THE SURFACE-RESPONSE ANALYSIS METHOD
Authors: Lim CC. , Kitto S.L.
Published: February 2019

Aconitum uncinatum L., a herbaceous native, is not widely available for the public because of difficulties in producing plants via conventional methods. The initial objective was to find a growth regulator combination and an antioxidant concentration that provided increased proliferation rates. Growth regulator combinations examined were BA (0, 11.1, 22.2, 44.4 μm), 2iP (0, 24.6, 49.2 μm), kinetin (0, 23.2, 46.5 μm), IAA (0, 28.5, 57.1 μm), and NAA (0, 26.9, 53.71μm). Antioxidants examined were ascorbic acid (0, 150, 500 ppm), citric acid (0, 150, 500 ppm), PVP (0, 250, 500 ppm), PVPP (0, 250, 500 ppm), and MPP (0, 0.5,1 ppm). Surface response analysis was used to select 30 (of more than 3000 possible) combinations of growth regulator or antioxidant concentrations. Experiments were subcultured every 4 weeks and terminated at 8 weeks. Total-shoot proliferation was significantly greater on media containing 44.4 μm BA + 46.5 pm kinetin. There were six antioxidant combinations that were no different from the control (150 ppm each ascorbic acid and citric acid). Further experiments looking at various BA + kinetin and antioxidant concentrations are needed to refine the media for maximal proliferation.
OPTIMAL CONDITIONS FOR CELL SUSPENSION CULTURES OF THLASPI CAERULESCENS AND BRASSICA NAPUS
Authors: Bundithya W. , Kitto S.L.
Published: February 2019

Thlaspi caerulescens (Brassicaceae), known as a Zn hyper accumulator, is able to accumulate and tolerate Zn, Ni, Cu, and Cd at high concentrations in its biomass. We are examining the feasibility of using cell suspensions of T. caerulescens and B. napus to study the effect of selected heavy metals on growth and nutrient uptake. Callus was initiated by culturing seedlings on basal medium containing MS salts supplemented with MS or B5 vitamins, 1, 2, 5, or 10 mg 2,4-D/liter, and 0.7% Phytagar. Cell suspensions were initiated by transferring calli to liquid basal medium containing MS or B5 vitamins, and 1 or 2 mg 2,4-D/liter, and were incubated on a gyratory shaker at 120 rpm. Growth of suspensions inoculated at 0.2, 0.4, or 0.6 g/25 ml was monitored for 13 days. Optimal conditions required to initiate and maintain suspension cultures of T. caerulescens and B. napus include MS medium supplemented with B5 vitamins and 1 mg 2,4-D/liter, an inoculation density of 0.4 g/25 ml, and a 2-week subculture schedule.
SURVIVAL OF LISTERIA MONOCYTOGENES ON LIGHTLY PROCESSED SPINACH
Authors: Babic Isabelle , Watada Alley E.
Published: February 2019

The population of Listeria monocytogenes inoculated on lightly processed spinach held at 5C or 10C remained constant for 9 days, whereas the populations of mesophilic aerobic flora, pseudomonas, and enterobacteria increased sharply. We studied the cause of the bacteriostatic activity of spinach leaves against L. monocytogenes. Listeria monocytogenes were inoculated at the concentration of 2 × 104 cells/ml in raw, autoclaved and vacuum filtration sterilized spinach macerates as well as in tryptic soy broth used as control. The concentrations after 24 hat 28C were 2 × 104, 4 × 107, and 4 × 105 cells/ml in respective spinach macerates and 4 × 108 cells/ml in tryptic soy broth. The anti-listeria activity was still present in spinach macerates sterilized by vacuum filtration but not in autoclaved macerates. In conclusion, the bacteriostatic activity against L. monocytogenes might be due to antimicrobial compounds present in spinach leaves or produced by the other microorganisms. Studies are being continued to identify the compounds involved in the anti-listeria activity.
EFFECTS OF LOW OXYGEN CONCENTRATIONS ON GLYCOLYSIS IN LIGHTLY PROCESSED CARROTS
Authors: Kato-Novuchi Hisashi , Watada Alley E.
Published: February 2019

Carrot (Daucus carota L.) shreds were stored under a continuous flow of 0.5% O2 (balance N2), 2% O2 (balance N2), or air for 9 days at 5C and 15C. The resulting changes in respiration and levels of the glycolytic intermediates were monitored. Low-oxygen atmosphere reduced respiration rate, but the RQ increased. The RQ was higher at 0.5% O2 than at 2% O2 atmosphere at both 5C and 15C. The most significant change in the levels of glycolytic intermediates was the accumulation of fructose 1,6-biphosphate. The level of fructose 1,6-biphosphate at 0.5% O2 was about 2-fold greater than at 2% O2 atmosphere at both 5C and 15C. The level of the other glycolytic intermediates at low-oxygen atmosphere was similar to that held in air atmosphere. These results suggest that phosphofructokinase activity in the tissue of carrots may increase under low-oxygen condition and it may be one of the controlling points in the glycolytic pathway affected by low oxygen concentrations.
COLD ACCLIMATION IN THE LEAVES OF SIBLING DECIDUOUS AND EVERGREEN PEACH: ALTERATIONS IN DEHYDRIN AND BARK STORAGE PROTEINS
Authors: Arora Rajeev , Wisniewski Michael , Rowland Lisa J.
Published: February 2019

Seasonal pattern of cold tolerance and proteins were studied in the leaves of sibling deciduous and evergreen peach (Prunus persica). In contrast to deciduous peach that undergoes endodormancy in fall, evergreen peach does not (leaves are retained and shoot tips elongate under favorable conditions) (Arora et al., Plant Physiol. 99:1562-1568). Cold tolerance (LT50) was assessed using electrolyte leakage method. Proteins were separated by SDS-PAGE. Electroblots were probed with anti-dehydrin (Dr. T. Close) and anti-19 kD, peach bark storage protein (BSP) antibodies. LT50 of leaves successively increased from about -7C (18 Aug.) to -15C and -11.5C (23 Oct.) in deciduous and evergreen genotypes, respectively. The most apparent change in the protein profiles was the accumulation of a 60-kD protein during cold acclimation in the leaves of deciduous trees; however, it did not change significantly in evergreen peach. Immunoblots indicate that 60-kD protein is a dehydrin protein. PAGE and immunoblots indicated that 19-kD BSP disappeared progressively during summer through fall in the leaves of deciduous peach, but accumulated to large amounts in bark tissues. Similar inverse relationship for its accumulation in leaf vs. bark tissue was not evident in evergreen peach. Results indicate that BSP expression may be regulated by altered source/sink relationship.
Effect of Sod Competition and Root Pruning on `Stayman' Apple Tree Growth and Fruit Cracking
Authors: Baugher Tara Auxt , Elliott Kendall C. , Glenn D. Michael
Published: February 2019

Three growth suppression treatments were compared during 1991 to 1993 on `Stayman' apple (Malus domestica Borkh.) trees grown in the T-trellis and the MIA trellis systems. All treatments—root pruning, K-31 fescue (Festuca arundinacea Schreb.), and K-31 fescue plus root pruning—suppressed tree growth compared to the nontreated control, but results were inconsistent between years and systems. Sod or sod plus root pruning reduced terminal shoot length in both systems in 2 out of 3 years. Root pruning decreased shoot length in the T-trellis in 1992. Sod decreased trunk cross-sectional area in the T-trellis in 1993. Treatments did not affect 3-year average yield efficiency but did appear to increase biennial bearing. Sod, with or without root pruning, decreased fruit cracking in the T-trellis 69% and 42%, respectively, in 1992, and sod plus root pruning decreased cracking in the MIA trellis 50%. Sod reduced fruit diameter in the T-trellis in 1992. Secondary effects of growth suppression treatments included increased light penetration and improved fruit color. Sod decreased leaf N and Mg and increased leaf P, K, and Cu. The Oct. 1993 stem water potential gradient from root to canopy was more negative in the sod plus root pruning treatment, and the osmotic potential of rootsucker leaves in the combination treatment was greater than in the control, indicating that sod plus root pruning alters the distribution of water within a fruit tree.
Root Cell Volume in the Planter Flat Affects Watermelon Seedling Development and Fruit Yield
Authors: Liu Aimin , Latimer Joyce G.
Published: February 2019

The growth of `Mirage' and `StarBrite' watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] transplants were evaluated in TODD 125, 100A, 150, 175, and 200 flats with root cell volumes of 18, 26, 36, 46, and 80 cm3, respectively. The effects of rooting volume restriction (RVR) on the number of leaves developed, leaf expansion, and shoot and root dry weight gain increased with time measured at 5, 10, 15, or 20 days after seedling emergence (DAE) for `Mirage' or 4, 8, 12, or 16 DAE for `StarBrite'. Generally, the greatest effect of RVR occurred between 10 and 15 DAE for `Mirage' and 8 and 12 DAE for `StarBrite' for most measurements. Root: shoot dry weight ratios generally were similar among the cell volumes. In a 1993 field test with `StarBrite' grown in the previously described flats, transplants from the TODD 125s produced the least growth and the poorest yield in terms of fruit per plant, total number of marketable fruit, and total yield. Transplants from TODD 200s produced a higher total yield than plants from other cell volumes.
Water Status of Sphagnum Peat and a Peat–Perlite Mixture in Containers Subjected to Irrigation Regimes
Authors: Heiskanen Juha
Published: February 2019

Various irrigation treatments were studied to determine their effects on the water and aeration conditions of peat-based growth media and evaporation from these media. Low-humified sphagnum peat and a mixture of this peat and perlite (in containers) were subjected to three contrasting irrigation treatments in which the container capacity was used as a target water content. The more frequent the reirrigations and the lower the vertical position within containers, the higher the matric potential of the growth medium averaged. Furthermore, the higher the water content of the growth medium, the higher the mean evaporation was from the containers. Within each irrigation treatment, slightly more water (on average) evaporated from the peat than from the peat–perlite mixture. Due to higher water retention and shrinkage during drying, a pure peat growth medium may increase the risk of waterlogging and, hence, O2 deficiency for containerized plants if plants are irrigated frequently to container capacity. To prevent waterlogging and high water loss by evaporation, low-humified sphagnum peat can be irrigated relatively infrequently (especially at low evaporation rates) and thoroughly within a short time (especially at high evaporation rates).
Safety and Efficacy of Halosulfuron-methyl for Yellow Nutsedge Topkill in Cool-season Turf
Authors: Fry J.D. , Dernoeden P.H. , Upham W.S. , Qian Y.L.
Published: February 2019

Field studies were conducted in Kansas and Maryland to compare the safety and efficacy of halosulfuron-methyl (HM) and bentazon for topkill of yellow nutsedge (Cyperus esculentus L.). Kentucky bluegrass (Poa pratensis L.) and creeping bentgrass (Agrostis palustris Huds.) treated with single (in Kansas) or sequential (in Maryland) HM (35 to 140 g·ha–1) or bentazon (1120 or 1680 g·ha–1) applications exhibited little injury, and treated turf had acceptable quality in all studies. Bentazon caused an unacceptable reduction in perennial ryegrass (Lolium perenne L.) quality at ≥5 weeks after treatment in four of five tests. Perennial ryegrass quality declined linearly with increasing HM rates (between 35 and 140 g·ha–1). In Maryland, HM (≥70 g·ha–1) elicited unacceptable perennial ryegrass quality for 2 or 3 weeks; however, in Kansas, quality was unacceptable for ≈1 week. In Kansas, yellow nutsedge topkill by HM (70 kg·ha–1) ranged from 52% to 97%. A single HM application (35, 70, or 140 kg·ha–1) provided > 97% topkill in Maryland. Yellow nutsedge topkill by bentazon (1680 g·ha–1) generally was inferior to that by HM (70 g·ha–1). Chemical names used: 3-(1-methylethyl)-1H-2,1,3-benzothiadiazin-4 (3H)-one 2,2-dioxide (bentazon), methyl 3-chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4-carboxylate (halosulfuron-methyl).
Coating Guavas with Cellulose- or Carnauba-based Emulsions Interferes with Postharvest Ripening
Authors: McGuire Raymond G. , Hallman Guy J.
Published: February 2019

Harvested, mature-green guava (Psidium guajava L.) fruit were coated with cellulose- or carnauba-based emulsions to compare the effect on fruit ripening and quality of ripened fruit. Coatings containing 2% or 4% hydroxypropylcellulose significantly slowed softening an average of 35% or 45%, respectively, compared to uncoated fruit (a delay of 1 to 2 days in September and 4 to 5 days by January). A 5% carnauba formulation slowed softening by 10% to 30% and was most effective at reducing weight loss. Neither of the cellulose- nor the carnauba-based coatings affected the decay susceptibility of softened fruit, but coated fruit did not develop as much color, had a lower soluble solids concentration, and were more prone to surface blackening in storage than uncoated fruit.
Characterization of Some Self-compatible Almonds. I. Pollen Tube Growth
Authors: Ben-Njima Nachida , _ _
Published: February 2019

Pollen tube growth was studied in 10 almond [Prunus amygdalus Batsch, syn. P. dulcis (Mill.) D.A. Webb] selections of the Zaragoza breeding program, whose main objective is the development of self-compatible cultivars. Self-compatibility was evident in eight of the selections, as indicated by the fact that pollen tube growth was similar following self- and cross-pollination. In the other two selections, pollen tube growth differed following self- and cross-pollination, one showing self-incompatibility and the other an irregular progression of crossed pollen tubes. The importance of the style in sustaining pollen tube growth was evident, and pollen tube growth was influenced by style type.
Variation in Horticultural Traits of `Bing' Sweet Cherry Associated with Ilarvirus Infection
Authors: Proebsting Edward L. , Ophardt David , Howell William E. , Mink Gaylord I. , Patten Kim D.
Published: February 2019

Thirty-five `Bing' sweet cherry (Prunus avium L.) clones were collected, primarily from old commercial orchards in central Washington; propagated on P. mahaleb L. rootstock; and their horticultural performance was evaluated. Nine of the 35 clones were not infected with the common pollen-borne ilarviruses prunus necrotic ringspot virus and prune dwarf virus—four of the clones after decades of exposure in commercial orchards. As a group, the nine virus-free clones produced larger trees with earlier fruit maturity and less rain cracking, but softer fruit, than did the 26 infected clones. These data challenge the general assumption that the presence of one or both of these ilarviruses is always detrimental. This assumption has driven development of many valuable virus certification programs and the adoption of virus-free trees as the standard for commercial fruit growing in most states.
Recognition of Brassica oleracea L. Resistance against the Silverleaf Whitefly
Authors: Farnham Mark W. , Elsey Kent D.
Published: February 2019

Resistance of a Brassica oleracea germplasm collection (broccoli, Italica Group; cauliflower, Botrytis Group; and collard and kale, Acephala Group) to silverleaf whitefly (SLW; Bemisia argentifolii Bellows and Perring) infestation was evaluated using several measures of insect infestation (including adult vs. nymph counts) taken at plant growth stages ranging from seedling to mature plant. An initial study was conducted in an outdoor screen cage artificially infested with the SLW adults; subsequent field trials relied on natural infestations. The glossy-leaved lines (`Broc3' broccoli, `Green Glaze' collard, and `SC Glaze' collard) had low SLW infestations in cage and field tests. SLW adult counts were less variable than similar comparisons using nymphal counts, although adult and nymph counts were positively and significantly correlated at late plant stages. Based on this study, comparing relative SLW adult populations would be a preferred criterion for identifying B. oleracea resistance to this insect.
Estimation of Genetic Variance of Starch Digestibility in Sweetpotato
Authors: Zhang Dapeng , Collins Wanda W. , Andrade Maria
Published: February 2019

Two experiments that included 25 sweetpotato [Ipomoea batatas (L.) Lam] genotypes were planted in various environments across North Carolina, and an in vitro screening method was used to investigate genotypic and environmental variance and genotype × environment (G × E) interactions of starch digestibility in sweetpotato. Significant genotypic variation of starch digestibility was found in both experiments. Some clones have starch digestibility equivalent to that of corn. Variance analysis from both experiments indicated that genotypic variance was the dominant component in starch digestibility. G × E interaction only accounted for 6.8% of the phenotypic variance in one experiment and for 5.9% in the other one. These results suggested that starch digestibility of sweetpotato could be improved to a level as that of corn through conventional breeding.
Flower Pigments within Hemerocallis fulva L. fm. fulva, fm. rosea, and fm. disticha
Authors: Griesbach R.J. , Batdorf L.
Published: February 2019

Various forms of Hemerocallis fulva differed in their relative anthocyanin: carotenoid ratios and the type of anthocyanin present. Hemerocallis fulva fm. fulva contained a single anthocyanin (cyanidin-3-rutinoside) and two carotenoids (zeaxanthin and lutein). Hemerocallis fulva fm. rosea contained a single anthocyanin (cyanidin-3-rutinoside) and traces of carotenoids. Hemerocallis fulva fm. disticha contained a single anthocyanin (delphinidin-3-rutinoside) and two carotenoids (zeaxanthin and lutein).
Automobile Radiator Antifreeze and Windshield Washer Fluid as IBA Carriers for Rooting Woody Cuttings
Authors: Chong Calvin , Hamersma Bob
Published: February 2019

Terminal stem cuttings of four evergreens [arborvitae (Thuja occidentalis L.), `Calgary Carpet' juniper (Juniperus sabina L.), `Hetzii' juniper (Juniperus virginiana L.), and Tamarix juniper (Juniperus sabina L.)] and four deciduous {Amur maple (Acer ginnala Maxim.), common lilac (Syringa vulgaris L.), ninebark [Physocarpus opulifolius (L.) Maxim.], and viburnum (Viburnum farreri Stearn)} woody landscape shrubs were treated with 0%, 0.1%, 0.3%, or 0.8% IBA mixed in talc or with 0%, 0.25%, 0.5%, 1.0%, or 1.5% IBA dissolved in 95% ethanol, radiator antifreeze (95% ethylene glycol), or windshield washer fluid (47.5% methanol). None of the carriers were phytotoxic to the cuttings. Cuttings treated with IBA in radiator antifreeze or windshield washer fluid produced rooting in most taxa similar to those treated with IBA in ethanol. Cuttings of the evergreen taxa produced more roots with liquid than with talc IBA at similar concentration ranges. There were some differences in rooting performance (expressed in terms of percent rooting, mean root count per rooted cutting, and length of the longest root per cutting) of taxa to solvents and IBA concentrations. However, such differences, if any, were generally small or commercially insignificant, except for ninebark, which rooted optimally with no IBA and exhibited a large reduction in percent rooting with increasing IBA concentrations in windshield washer fluid. Chemical name used: indolebutyric acid (IBA).
DNA AMPLIFICATION FINGERPRINTING (DAF) IDENTIFIES CLOSELY RELATED CULTIVARS IN THREE SERIES OF CHRYSANTHEMUMS
Authors: Scott M.C. , Caetano-Anollés G. , Trigiano R.N.
Published: February 2019

The genetic distance of closely related cultivars of Dendranthema grandiflora (chrysanthemum) was assessed using DAF. Thirteen cultivars of chrysanthemum included in the study were members of the following series: Charm (five), Davis (four), and Pomona (four). The genetic variability within and between series were evaluated using 11 arbitrary octamer primers. A few polymorphic loci were evident that uniquely identified closely related cultivars within a series. In contrast, there were many polymorphisms between members of different series. Genetic distances between cultivars within and between series were calculated using marker comparison and UPGMA (cluster analysis). The average distance between series was 10-fold greater than between cultivars within a series. DNA from all cultivars belonging to a series also were bulked to generate DNA profiles containing unique amplified products for each series. Polymorphic loci that were generated by the DAF technique possibly could be used for patent protection and phylogenetic studies and may be useful in breeding for chrysanthemums.
INCIDENCE AND SEVERITY OF WATERMELON (CITRULLUS LANATUS) HOLLOWHEART
Authors: Elmstrom G.W. , McCuistion F. , Maynard D. N.
Published: February 2019

Watermelon varieties were evaluated for hollowheart (HH) at Bradenton, Leesburg, and Quincy, Fla. HH varied with location, variety, and season. Among icebox varieties, `Sugar Baby', `Baby Gray', and SSDL had less HH than `Tiger Baby', `Minilee', and `Mickylee'. Among standard varieties, `Sangria' and `Jubilee II' had less HH than `Crimson Sweet' and `Royal Sweet'. In 1990, HH was more severe at Quincy than at Bradenton or Leesburg, but the ranking of seedless entries was similar among the locations. HMX 7928, `Nova', `Tycoon', and `Millionaire' had least HH, and `Jack of Hearts', `Ssupersweet 4073', `Ssupersweet 5344', and `King of Hearts' had the most HH. `Jack of Hearts' and `Crimson Sweet' fruit were cut and evaluated in Spring 1993 at 5, 12, 19, 26, and 33 days after anthesis. Incidence of HH was low in 5- and 12-day-old fruit, increased in fruit that were 19 or 26 days old, and did not increase in older fruit. About one-third of fruit from both varieties had some HH. Among the seven entries in another test in Spring 1993, `Tri-X-313' had the least HH and `Crimson Sweet', `Jack of Hearts', and `Jubilee II' had the most.
EFFECTS OF ROWCOVER AND TRANSPLANT METHODS ON SUMMER SQUASH PRODUCTION
Authors: Brown J.E. , Yates R.P , Stevens C. , Khan V.A.
Published: February 2019

Effects of planting methods and rowcover on the production of yellow crookneck squash, Cucurbita pepo L. var. melopepo Alef., were evaluated over 2 years at the E.V. Smith Research Center, Shorter, Ala. Summer squash was direct-seeded or transplanted in the field with or without black plastic mulch and grown with or without rowcover. Yield of transplanted squash was significantly increased over the same squash direct-seeded. Neither plastic mulch nor rowcover had an effect on summer squash production. Transplants matured 8 to 10 days earlier than the direct-seeded plants.
HORTICULTURAL YOUTH EDUCATION: THE MISSING LINK
Authors: Ruppert Kathleen C.
Published: February 2019

Most college professors spend little time helping youth (kindergarten to 12th grade) learn about horticulture, and the elementary and secondary schools seem to have created a dividing line between scientific concepts and practical life-long skills. Biology classes continue to emphasize the chemical processes of photosynthesis and deemphasize the nurturing, caring, dependability, responsibility, sense of accomplishment, and other life-long skills that can be obtained from growing plants. However, retail garden centers and chain stores are increasingly offering books and supplies on gardening and related activities for children. Seed companies market and package seeds just for children. Botanical gardens and arboretums are including youth horticultural activities as part of their on-going educational programs. The involvement of university educators in horticultural youth education can assist the “trickle up” theory to the parents of children along with affecting future voters. Take the first step to see what classroom horticultural materials are available in your state. Currently many teachers have an interest in learning more about horticulture but need educational materials. In addition, there is a large number of volunteers interested in this endeavor. Do your part and help develop accurate horticultural materials for these instructors to use in formal and informal educational settings.
THE SFASU ARBORETUM WOODY AND HERBACEOUS PLANT EVALUATION PROGRAM: PLANTS WITH PROMISE
Authors: Creech David
Published: February 2019

The mission of the SFASU Arboretum is to promote the conservation, selection, and use of the native plants of Texas and to encourage diversity in the urban landscape philosophy of the region. A decade since its inception, the 10-acre arboretum features many uncommon, unusual, and difficult-to-find species and cultivars, many deserving greater use in the region. The living collection has been acquired through botanical gardens, arboretums, private collections, the nursery industry, and expeditions. The list of promising plants that have surfaced includes many that are not easily available in the trade. The issues involved in woody and herbaceous plant evaluation include computer mapping and record keeping constraints, the long-time frame for evaluation with many woody plants, and difficulties in propagation. The arboretums's plant acquisition policy and record keeping and computer mapping system is currently tracking more than 2500 taxa in the living collection. An overview of the first decade of plant performance and a strategic plan for acquisition, propagation, evaluation, distribution, and promotion are presented.
USE OF SPANISH MOSS (TILLANDSIA USNEOIDES L.) AS AN INDICATOR OF TRACE ELEMENTS IN URBAN AREAS
Authors: McWilliams Ed , Harp Derald A.
Published: February 2019

Spanish moss (Tillandsia usneoides) samples were deployed at 36 locations in a 6 × 6-grid system in northeastern Texas during the summer months of 1989 and again in the winter months of 1990. Analytical methods, including inductively coupled plasma emission spectrometry (ICP) and neutron activation analysis (NAA), were used in analyzing samples for sulfur, selenium, arsenic, sodium, and aluminum. Concentrations of most elements in Spanish moss samples were much higher in summer than winter. The highest concentrations of sulfur were found in Van Zandt, Wood, Titus, and Bowie counties. These results suggest that on average sulfur stays in the region in which it was generated. Potassium and sodium were highly correlated with latitude and seem to originate from the Gulf of Mexico.
COMBINING SHRINKAGE CURVES FOR SEVERAL CUCUMBERS RECEIVING SAME-STORAGE TREATMENT WHEN SLOPES ARE NOT EQUAL AND VARIANCES ARE HETEROGENEOUS
Authors: Mullinix Benjamin , Purvis Albert
Published: February 2019

Five `Poinsett' cucumbers were selected at random for each treatment in a postharvest storage experiment. Each cucumber was weighed initially, covered by wax “E”, and weighed each day afterwards for 9 days. Percentage loss was computed for each day. Quadratic regression curves were fit for each cucumber and for all in a single analysis. In most cases, variances were not homogeneous among the five cucumbers. Using the regression coefficients for each cucumber, an average of the five was made and appropriate standard errors were computed. Percent loss data was transformed using SQRT. The number of cases where homogeneity of variances were found increased. Mixture of large and small cucumbers by weight tended not to be homogeneous, whereas mixing of cucumbers of similar weights were improved with square-root transformation.
TRANSFORMATION OF ONION CALLUS VIA PARTICLE BOMBARDMENT
Authors: Peffley Ellen B. , Hart Melanie A.
Published: February 2019

Particle bombardment was investigated as a potential transformation method for onion. Seeds of Allium cepa `TG 1015' were planted onto BDS medium and placed in a dark incubator at 25C for germination. Two to 3 weeks after the seeds were germinated, meristems (1 to 2 mm) were excised and placed onto BDS medium containing 2 mg 2,4-D/liter for callus initiation. Callus was transferred monthly onto fresh BDS medium containing 2,4-D until bombardment. The reporter gene for B-glucuronidase (GUS) expression was used to assess efficiency of gene delivery in all particle bombardments. Characteristics examined were target distance and helium pressure (particle velocity). Tissues were subjected to the 5-bromo-4-chloro-3-indoyl-B-D-glucuronide (xgluc) test for detection of GUS activity. Measurements were taken on particle dispersion as affected by target distance and helium pressure. GUS expression was detected in putatively transformed tissues.
AUXIN TYPE DURING INDUCTION AFFECTS PECAN SOMATIC EMBRYO DEVELOPMENT AND MORPHOLOGY
Authors: Wetzstein Hazel Y. , Rodriguez Adriana P.M.
Published: February 2019

Somatic embryogenic cultures of pecan (Carya illinoinensis) were induced on medium with either naphthaleneacetic acid (NAA) or 2,4-dichlorophenoxyacetic acid (2,4-D). Percent embryogenesis, embryo development, and subsequent performance were assessed. Cultures induced on medium with NAA were more zygotic-like, with a higher frequency of embryos that had well-defined shoot apices. In contrast, cultures induced with 2,4-D exhibited more extensive callusing and more fused and/or abnormal embryos. Adjustment of the auxin used during induction may be a means of obtaining higher quality embryos, that have higher rates of conversion into plants.
GENETIC TRANSFORMATION AND REGENERATION OF TRANSGENIC SWEETPOTATO PLANTS.
Authors: Egnin Marceline , Prakash C.S.
Published: February 2019

This study aimed to optimize factors for the efficient delivery of foreign genes into sweetpotato using Agrobacterium tumefaciens and develop transgenic plants. Disarmed Agrobacterium C58 carrying a binary vector pBI 121C2H with gusA, nptll, and the nutritional protein asp-l genes was used to cocultivate (4 days) petiole explants of the sweetpotato genotype P1318846-3. Pre-incubation of petioles for 3 days on MS medium with 2,4-D (0.2 mg·liter–1) before infection resulted in higher transformation. Putative transgenic shoots were obtained by transfer of petioles to MS medium with TDZ (0.2 mg·liter–1) and kanamycin (80 to 140 mg·liter–1). The PCR amplification of gusA, nptll, and asp-1 genes in the 37 putative transgenic shoots showed that six plants contained the three genes. However, none of these plants showed histochemical expression of the gusA gene. The introduced gene may have been methylated resulting in the lack of its expression. DNA blot hybridization studies are underway to verify the presence and integration of the transgenes.
PHENOLIC VARIATION IN LEAF POSITION IN APPLE
Authors: Garcia M.E. , Rom R.C. , Murphy J.B. , Felton G.W.
Published: February 2019

The foliar phenolic content of 21 apple cultivars was evaluated. Ten leaves were sampled randomly from three positions on current-season terminal shoots. Shoots were divided as tip, middle, and basal positions. The phenolic content was determined by spectrophotometric method (390 nm) using diphenylboric acid 2-aminoethyl ester as the reagent and caffeic acid as standard. Cultivars varied significantly in phenolic content. `Stark Ultra Red' had the highest amount, and `Liberty' had the lowest amount. Significant variations in the phenolic content due to leaf position were observed. Phenolic content was highest in leaves from the tip position, and it decreased toward the basal portion of the shoot. Factors affecting the phenolic content of apple cultivars will be investigated to determine apple × insect interactions.
ROW SPACING AFFECTS YIELD OF MACHINE-HARVESTED GREEN-MATURE SOUTHERNPEAS
Authors: Buckley Blair , Pee Katharine
Published: February 2019

Yield of southernpeas machine-harvested at the green-mature stage generally have not been sufficient for machine-harvest to be profitable. Using narrow row spacings has been proposed to increase yield per hectare. A study was conducted in 1993 and 1994 to examine the effect of row spacing on yield of machine harvested green-mature southernpeas. `Texas Pinkeye' was planted at row spacings of 53, 89, and 107 cm single drilled (SD), and 107 cm double drilled (DD). Marketable yield from the 53-cm row spacing was greater than from the wider row spacings. The yield response was primarily linear. Marketable yield from the DD 107-cm row spacing did not differ significantly from that of the SD 107-cm row spacing. Marketable yield from the DD 107-cm row spacing was less than that from the 53-cm spacing. The plant population per hectare for the two treatments was the same. In 1993, there was a linear response for percentage of pods mature at harvest. The percentage of mature pods was greatest for the 53-cm row spacing.
CONSUMER PREFERENCE FOR ALTERNATE CHRISTMAS TREE SPECIES
Authors: Tilt Ken , Behe Bridget , Williams David , Potter Heath , Bunn Dwight
Published: February 2019

A survey was developed evaluating the preference of consumers for purchasing three alternative Christmas tree species. Trees included: Pinus virginiana, a traditional Alabama Christmas tree; a containerized Ilex × `Nellie R. Stevens'; and a cut × Cupressocyparis leylandii. Virginia pine and leyland cypress were rated higher than the holly. The average rating on a scale of 1 to 5 for the Virginia pine and the leyland cypress was 3.75 and 3.63, respectively. Consumers rated the holly an average of 3.29. A rating of 1 indicated a strong negative response and a rating of 5 offered a strong positive response for buying the tree. The median rating for all three species was 4, indicating that 50% of the participants rated them a 4 or higher. The mode, or most frequent rating, was 5 for all three species. Although the average rating for the holly was lower than the average for the Virginia pine and leyland cypress, the holly and the leyland cypress may have a market niche with >50% of the respondents indicating that they would purchase the trees.
DETERMINING COST OF PRODUCTION FOR THREE ALTERNATIVE NURSERY PRODUCTION METHODS
Authors: Montgomery C.C. , Behe B.K. , Adrian J.L. , Tilt K.M.
Published: February 2019

Aboveground container production revolutionized woody plant production. In-ground pot-in-pot container production combines the benefits of container production with traditional field production. Our objective was to determine the specific costs of production for field-grown, aboveground container, and pot-in-pot production methods for Lagerstroemia indica. We found differences in production cost with varying levels of input required by each production method. Pot-in-pot production systems had higher fixed and variable costs and a higher initial capital investment compared to the other two production methods. However, per unit production costs were similar to aboveground container production due to lower labor and equipment requirements.
INTER- AND INTRA-SPECIFIC VARIATION AMONG FOUR IPOMOEA SPECIES AS DETECTED BY RAPD ANALYSIS
Authors: Zhang Dapeng , Collins Wanda
Published: February 2019

To understand the prospects of applying the RAPD technique to assay genetic diversity in Ipomoea, four species (I. batatas, I. trifida, I. triloba, and I. ×leucantha) were analyzed for RAPD molecular markers. Six accessions of each species were used. Significant RAPD polymorphisms were detected within each species. Of 20 primers used, nine produced clear scorable polymorphic bands. The number of polymorphic bands produced per primer ranged from two to nine. Pair-wide genetic distance was calculated based on “band sharing”. The SAS-CLUSTER procedure was used to build a hierarchical species dendrogram. The four species were clearly separated by the clustering, which agrees with their existing taxonomic relationship. This study shows that RAPD analysis can be a powerful tool for identifying duplicates of germplasm acessions and for assessing genetic diversity. The procedures are relatively inexpensive and easy to perform and could be valuable in preliminary assessment of field genebank collections to separate species and indicate duplications in collected material.
SELECTING VIGNA UNGUICULATA GERMPLASM FOR RESISTANCE TO COWPEA CURCULIO AND OTHER POD-DAMAGING INSECTS
Authors: Chambliss Oyette L. , Hunter A. Gene
Published: February 2019

Correlation analysis was used as an aid in developing a scoring system to determine superior lines among 288 entries evaluated for resistance to cowpea curculio, southern green stink bug, and leaffooted bug. The following selection criteria were used (min/max values): days to harvest (58 to 111); sound pods (17% to 100%); curculio larval weight (3.3 to 10.4 mg) and mortality (0% to 80%); larval exit holes per pod (0.0 to 2.2) in a random sample of 25 pods; larval exit holes per pod (0.0 to 8.6) in a 10-pod sample selected for presence of punctures; punctures per pod (one to 15); punctures per exit hole (one to 14); exit holes per puncture (zero to one); curculio damaged seed (0% to 93%); stinkbug damaged seed (0% to 71%); sound seed (0% to 98%); pod length (8 to 25 cm); pod weight (1.3 to 9.2 g); seed per pod (five to 19); and average seed weight (10 to 327 mg). Lines ranking best for pod insect resistance were UCR212 = BAMBEY-5, UCR306 = IT82D-713, UCR194 = BBR-42, PI-218122, UCR90 = T W-3046, UCR200 = 24-lA, PI-115679, PI-145198, AU9lP3 = CCR-20, UCR202 (BROWN SEED), and IT83S-911.
Suppressing Pecan Aphid Populations Using Potassium Nitrate Plus Surfactant Sprays
Authors: Wood Bruce W. , Payne Jerry A. , Smith Michael T.
Published: February 2019

A 4-year field study on pecan [Carya illinoinensis (Wangenh.) K. Koch] provided indirect support of the supposition held by some U.S. pecan growers that air-blast foliar sprays of potassium nitrate (KNO3) plus surfactant enhances nut yield. While these treatments did not measurably influence yield components, foliar K nutrition, or net photosynthesis, they did suppress “yellow-type” aphid populations. While air-blast sprays of water alone suppressed aphid populations, the inclusion of KNO3 plus surfactant provided an additional level of suppression.
Response of Diverse Lettuce Types to Fertilizer Phosphorus
Authors: Sanchez C.A. , El-Hout N.M.
Published: February 2019

Four field experiments were conducted from 1990 to 1992 on Histosols in southern Florida to compare the relative response of various types of lettuce (Lactuca sativa L.) (i.e., leaf, Boston, Bibb, romaine, and crisphead lettuce) to P fertilization. All lettuce types showed large yield and quality responses to P fertilization. Because environmental conditions affected yield potential, P rates required for optimal yield varied for lettuce types across experiments. However, with the exception of Boston, the P rates required for optimal yield were similar when averaged over all experiments. Furthermore, the relationship between relative yield and soil-test P across all seasons showed that a similar soil-test P index level was required for maximum yield of all lettuce types. Overall, the results of this study suggest that existing soil-test-based fertilizer recommendations for crisphead lettuce are adequate for other lettuce types currently grown.
Gro-Mate Soil Amendment Improves Growth of Greenhouse-grown `Chardonnay' Grapevines
Authors: Reynolds Andrew G. , Wardle Douglas A. , Drought Brian , Cantwell Robert
Published: February 2019

Own-rooted, glasshouse-grown `Chardonnay' vines (Vitis vinifera L.) were planted in a sand medium to which was added one of five levels of granular Gro-Mate (GM), a commercial humate (0, 8, 16, 32, 64 g/pot; 0 to 35 g a.i./pot). Two other treatments consisted of weekly (1× W) or twice-weekly (2× W) applications of liquid GM, whose cumulative addition over the 28 weeks of the experiment totaled 6.7 and 13.4 g a.i., respectively. Shoot length responded to increasing level of GM in a predominantly cubic fashion, with 32 g/pot resulting in the longest shoots. Fresh and dry weights of leaves, shoots, and roots, as well as leaf count and area, exhibited increasing linear or quadratic trends in response to increased level of granular GM. GM increased soil organic matter, K, Ca, Mg, Fe, Mn, Cu, Na, and S and also increased petiole Fe and lamina P, K, and Fe. Liquid treatment resulted in lower soil pH, organic matter, bulk density, and Fe and higher soil conductivity, NO3, P, K, Mg, Cu, Zn, Na, and S than the granular treatments, as well as higher petiole and lamina N and K, lower petiole and lamina P, and lower petiole Zn. Compared to the 1× W treatment, the 2× W produced lower soil bulk density and higher P, lower lamina K, Mn, and Fe; lower petiole Mn; and higher petiole Cu. Plant tissues contained extremely high levels of Mn irrespective of treatment, whereas liquid treatments resulted in high soil NO3 levels. Although liquid GM cannot be recommended for young grapevines under an application regime such as described here, preplant applications of granular GM may have potential for improving growth of young vines in coarse-textured soils. High granular or excessive liquid applications may result in leaf necrosis and retarded growth.
`Fortune' Mandarin Quality following Prestorage Water Dips and Intermittent Warming during Cold Storage
Authors: Schirra Mario , Mulas Maurizio
Published: February 2019

Freshly harvested `Fortune' mandarins (Citrus reticulata Blanco) were dipped for 3 minutes in 25 or 52C water and then stored for 5 weeks at 2C. Then, the fruit were or were not intermittently warmed at 10C for 3 days after each 4-day storage period. All fruit then were held at 20C for 1 week to simulate retail marketing. Chilling injury was more severe in fruit dipped in 25C water and stored at 2C than in fruit dipped in 25C water and stored under intermittent warming. The hot dip treatment significantly reduced the extent of damage during storage and the subsequent 1 week of holding at 20C. The hot dip treatment reduced the incidence of fungal decay, especially during holding at 20C. Dip temperature and storage conditions slightly affected fruit physiological and quality characteristics. We conclude that prestorage hot dip treatments can be used to improve `Fortune' mandarin storing qualities. Also, this practice may be combined with intermittent warming during cold storage, and it could help limit fungicide use in postharvest treatments.
Ripening of Kiwifruit following Simulated Brushing with Commercial Brushes
Authors: Massantini R. , Lanzarotta L. , Botondi R. , Mencarelli F.
Published: February 2019

Brushing of `Hayward' kiwifruit [Actinidia deliciosa (A. Chev.) C.F. Liang et A. R. Ferguson var. deliciosa] to remove trichomes reduced their marketable life. Fruit were brushed with polypropylene brushes having bristles of 0.60, 0.50, 0.30, and 0.25 mm in diameter. The two smallest-diameter bristles removed about 0.1 g of trichomes per fruit. The larger diameter bristles removed 12% more material, including some surface tissue particles. Brushing accelerated ripening during subsequent storage of fruit for 4 days at 4C as indicated by increases in ethylene production and soluble solid concentration and a decrease in firmness. The larger the bristle diameter, the greater the acceleration of ripening. The largest diameter did not accelerate ripening as much as 0.50-mm bristles due to the lower resistance to bending (0.85 N and 2 N for 0.60- and 0.50-mm bristles, respectively) and their greater length. Small surface wounds, visible under the microscope, may have caused the higher ethylene evolution and the consequent ripening response.
Resistance to Twospotted Spider Mite and Strawberry Aphid in Fragaria chiloensis, F. virginiana, and F. ×ananassa Clones
Authors: Shanks Carl H. , Moore Patrick P.
Published: February 2019

More than 170 clones of Fragari ×ananassa Duch., F. chiloensis (L.) Duch., and F. virginiana Duch. were tested for resistance to the twospotted spider mite (Tetranychus urticae Koch). Twenty-seven clones had >75% fewer mites than did F. ×ananassa `Totem', a susceptible clone. About two-thirds of the clones also were tested for resistance to the strawberry aphid [Chaetosiphon fragaefolii (Cockerell)]. Survival and reproduction was significantly lower on two clones each of F. ×ananassa and F. virginiana than on `Totem'.
Flowering Responses of Easter Cactus Clones at Optimal and Supraoptimal Temperatures
Authors: Boyle Thomas H.
Published: February 2019

The effects of temperature and clonal genotype on flowering of Easter cactus (Rhipsalidopsis Britton & Rose) were investigated in two experiments. Plants of `Crimson Giant', `Evita', `Purple Pride', and `Red Pride' were exposed to 6 weeks of either 10C or 18C night temperature (NT) under 9- to 9.5-hour natural daylengths (ND), and afterwards were forced at 18C NT and long days (LD). All clones produced fewer flowers when exposed to 18C and ND as compared with 10C and ND; however, the clones varied significantly in their flowering responses. Relative to 10C NT and ND, exposure to 18C NT and ND resulted in an 84% to 95% decrease in the number of flower buds for `Evita', `Purple Pride', and `Red Pride', but only a 50% decrease in the number of flower buds for `Crimson Giant'. In another experiment, 23 clones were exposed to 18C NT and 8-hour short days for 6 weeks, then forced at 18C NT and LD. The clones exhibited differences in percentage of plants flowering, days to flowering, percentage of apical phylloclades flowering, and number of flower buds. `Crimson Giant' outperformed all other clones. Further breeding and selection may yield genotypes that flower more prolifically at 18C minimum than current cultivars.