bluuebunny/crossref_metadata_2025 huggingface dataset:
Lime and Micronutrient Additions to Pine Bark Affect Growth of Nine Landscape Tree Species
Authors: Wright Amy N. , Fanelli Jody K. , Niemiera Alex X. , Harris J. Roger , Wright Robert D.
Published: February 2019

Although the practice of amending a pine bark substrate with lime and micronutrients is common in the nursery industry, the effect of these amendments on the growth of container-grown landscape trees has not been documented. The objective of this study was to determine the lime and micronutrient preferences for a wide range of landscape trees grown in pine bark. Approximately 10 seedlings per pot for each of nine species of trees were greenhouse-grown in pine bark-filled 3-gal containers. Initial pH of the bark was 4.7. Preplant bark treatments were: unamended (control), dolomitic lime only (3.57 kgμm–3), micronutrients only (Micromax™, 0.89 kgμm–3), or lime plus micronutrients (previously stated rates). All seedlings except one per pot were harvested at week 12, and shoot height was determined. Remaining seedlings were grown until week 19, at which time final shoot height was determined. Bark solutions were extracted (pour-through method) at week 7. Adding micronutrients increased height for all species by week 19. Adding lime either had no effect on height or supressed height. Micronutrient additions increased solution concentrations of Ca, Fe, Mn, Cu, and Zn, but in the presence of lime these increases were diminished. Under the conditions of this experiment, amending pine bark with micronutrients is essential for maximum height of these tree species, while a lime amendment is unnecessary.
The Effect of Mild Water Deficit on Basil Yield and Quality
Authors: Warner Jennifer , Markhart Albert H.
Published: February 2019

Secondary compounds, essential oils, and flavor components of leaf tissue often increase in response to environmental stress. The objective of this study is to determine if a simple measure of soil matric potential could be used to generate mild plant water stress in sweet basil, which would improve the flavor components of the foliage. Sweet basil was grown in Universal Soil Mix with adequate water and fertilization in greenhouses supplied with 18 h of high-pressure sodium supplemental lighting until the third pair of leaves was fully expanded. Aquaprobe matric potential sensors were installed in the center of the pot and soil matric potentials recorded daily. Water was withheld from stressed plants until the soil water potential reached –4 bars. Treatments consisted of one or two stress cycles. Plants were harvested 24 h after rewatering and fresh and dry weights determined. The youngest two fully expanded leaves were placed in zip log bags and used in a taste test. The two water stress treatments decreased leaf fresh weight by 10% and 16%, respectively, decreased total plant dry weight by 6% and 10%, respectively, and had moderate effect on flavor intensity as rated by our taste test panel. The substantial decrease in yield suggests that –4 bars was too severe a stress to be used commercially. The Aquaprobe sensor was an easy to use economical way to monitor soil water and could be useful in regulating watering in a greenhouse environment.
Hydrothermic Treatment Effects on Some Ripening Changes on Mango Fruits (Mangifera indica L) `Crillo de Bocado' during Storage: II. Chemical Parameters
Authors: Manzano Juan E , Valor Oswaldo
Published: February 2019

Mango fruits `Criollo de Bocado' harvested at the mature-green stage were treated with a hydrothermic treatment of 55 °C for 3 min and stored for 20 days at temperatures of 10 ± 2, 15 ± 2 and 28 ± 2 °C. A randomized design 2 × 3 × 4 with three replications was used. Some chemical parameters were analyzed, such as total soluble solids content (% TSS), pH, tritatable acidity, and TSS/tritatable acidity ratio. TSS content increased with storage time at low temperature. The pH increased measurably with storage temperature, while tritatable acidity values results had inconsistent data.
Chemical Growth Retardant Application to Scaevola
Authors: Starman Terri Woods , Williams Millie S.
Published: February 2019

Fan flower (Scaevola aemula L.) has become a popular specialty bedding and hanging basket plant in the United States. The genus contains several species from Australia and the Indo-Pacific region and there exists a wide diversity of growth habits and flower colors, including blue, violet, pink and white. Our objective was to measure the effect of type of growth retardant, method of application, and chemical concentration on S. aemula `New Wonder', `Mini Pink Fan', 'Purple Fan', and `Royal Fan', S. albida 'White Fan', and S. striata `Colonial Fan'. Variables measured included days to flower, plant width, flower stem number, flower stem length, and flower number per stem. Uniconazole applied as a media drench to S. aemula `New Wonder' at 1.0 and 2.0 mg·L–1 decreased plant width and flower stem length without affecting time to flower or flower number. Therefore, number of flowers per cm of stem length on S. aemula `New Wonder' was increased, resulting in attractive, compact clusters of flowers on pendulus stems. Paclobutrazol drench (4.0 and 8.0 mg·L–1) was also effective. Daminozide spray (5000 mg·L–1) reduced plant width but flower number was reduced. Ancymidol foliar sprays and media drenches (all rates) had no effect on the parameters measured. Ethephon (500 and 1000 mg·L–1) reduced plant width, but delayed flowering and reduced flower number. Uniconazole drenches were beneficial in improving the quality of S. aemula. `New Wonder' grown in hanging baskets, but the growth control was not long-lived. The effect of uniconzole on plant growth varied with Scaevola species and cultivars.
Application of Processed Fiber for Nursery Crop Production
Authors: Shirazi A.M. , Fuchigami L.H.
Published: February 2019

Composted Tillamook Methane-digested dairy manure (processed fiber) plus woodwaste from landfills at Tillamook, Ore., was compared with Langerwerf, Calif., processed fiber amended with woodwaste from Tillamook, a mixture of peatmoss and pumice, and two commercial mixes from Black Gold Inc., Hubbard, Ore. Electrical conductivity, water-holding capacity, pH, cation exchange capacity, and mineral contents of Tillamook processed fiber with a mixture of wood waste were within the acceptable range for production of some nursery crops. Tillamook processed fiber with a mixture of wood waste media were favorable for the germination and growth of the lettuce and radish cultivars. The performance for seed germination was comparable to the performance of both Black Gold media and better than the other media. The growth of marigold `Bonanza Yellow', petunia `Plum Maddness', and salvia `Purple Sizzler' in Tillamook processed fiber wood media, supplemented with weekly feeding of fertilizer, was comparable to their growth in Black Gold media and better than the other media. The growth of `Double Delight' rose plants in Tillamook processed fiber wood media was similar to their performance in Black Gold media.
Evaluation of Tillage Methods and Cover Crops for Sweetpotato Production
Authors: Jett Lewis W.
Published: February 2019

The marketable yield of the sweetpotato [Ipomoea batatas (L.) Lam.] can be limited by environmental variation. Cover crops may ameliorate water and temperature stress encountered during the growing season while reducing soil erosion and weed competition. The objective of this research was to investigate the commercial production of sweetpotatoes with cover crops in a conventional or conservation tillage system. Rye, ryegrass, wheat, and triticale were broadcast-seeded in Fall 1995 and 1996. Three weeks before transplanting, the cover crops were plowed-in or retained as an in situ mulch. Uniform slips of `Beauregard' sweetpotato were transplanted in May and June of each year, and standard cultural practices (with the exception of cultivation) were performed. In 1996 and 1997, conservation tillage increased marketable yield of sweetpotato 15% with a noticeable improvement in quality. Ryegrass produced the largest quantity of biomass and was effective in reducing soil temperature during storage root initiation and development. Conservation tillage resulted in a significantly higher root set relative to the control. Conservation tillage seems to have advantages as an alternative tillage method for sweetpotato production.
Use of the Biological Compound Ret-flo Px357 to Increase Yield and Improve Fruit Quality of Tomato and Banana Grown in a Greenhouse
Authors: Ait-Oubahou A. , El-Otmani M.
Published: February 2019

In the past few years, there has been a high demand for the use of new generations of biological products in modern agriculture. Several of these products are friendly to the environment and guarantee good yield and quality of many horticultural products. Pesticide residues resulting from heavy applications of a wide range of chemicals to control various pests is becoming a serious problem for exports, as well as for local consumption, of many products. This study was initiated to examine the effect of Ret-flo Px-357 a biological compound from EIBOL Co., Spain, developed to induce resistance to nematode infestation on several plants. `Daniella' tomato and `Grande naine' banana grown in plastic greenhouses were used to evaluate these effects. Two ground applications of Px357 at the rate of 20 L·ha–1 were used at 4-month intervals in Oct. 1996 and Feb. 1997. These treatments have stimulated root formation, stem diameter, and plant height. In tomato plants, the number of flowers and fruits per cluster was greater in treated than in non-treated plants. After harvesting eight clusters from the tomatoes, the number, size, individual fruit weight and total production of fruits from treated plants were greater than for the control plants. Similar results were observed in banana plants, which showed larger pseudo-stem and heavier fruit bunches at harvest. Variation in nematode population as well as plant nutrition during plant growth will be discussed, and results related to fruit quality will be presented and commented upon.
Final Results of Propagation Experiments to Show Distribution of Noninfectious Bud-failure in `Carmel' Almond
Authors: Kester D.E. , Shackel K.A. , Gradziel T.M. , Micke W.C. , Viveros M.
Published: February 2019

The distribution of the potential for noninfectious bud-failure (BFpot) was shown for the entire `Carmel' almond cultivar by propagating from single buds on single budsticks on individual trees of separate source blocks of commercial nurseries. Approximately 2700 progeny trees were grown at the same test site. The gradual increase in the expression of BF (Bfexp) in progeny trees from individual source trees shows a continuous range of latent BFpot among individual source trees directly correlated to five (or six) consecutive generations of vegetatively propagated source orchards. This pattern shows a continuous gradient in expression (vertical variation). A continuous gradient in expression also exists among progeny trees originating from the same source tree (horizontal variation). Individual source trees were identified whose progeny produced little or no BFexp when grown for 5 or more years in a high temperature test site. These studies confirm that noninfectious bud-failure (and probably other genetic disorders) represent persistent variants of a specific gene(s) whose genepot changes during vegetative growth sequences to bring about differential expression over time (“age”) and developmental patterns. These represent a class of clonal variants which are “age-related” and include “phase changes”, “juvenility–maturity” phenomena, and can affect morphology, thorniness, ease of rooting, etc. BF is related to a gene that affects environmental adaptation of the almond. Control is through the selection, maintenance and management of foundation clones.
Identification of Flavonoids from the Seedcoats of Phaseolus vulgaris L. Beans of Known Genotype for Seedcoat Color
Authors: Beninger C.W. , Hosfield G.L.
Published: February 2019

A number of pure flavonoid compounds have been isolated and identified from seedcoats of bean (Phaseolus vulgaris) with known genotypes for seedcoat color. Kaempferol-3-O- -D-glucopyranoside was found to be the major seedcoat flavonol of the “brown” genotypes yellow brown (P C J G b v), mineral brown (P C J G B v), mat mineral brown (PC j G B v), buffy citrine (P C J g B v). This kaempferol glycoside was also found in a yellow bean (`prim' P C j G b v) of the manteca market class, but the diglycoside kaempferol-3-O- -D-glucopyranoside-(2 1)- -D-xylopyranoside was another major flavonol found in manteca. The “brown” genotypes also contained proanthocyanidins that are currently being characterized, but no tannins or proanthocyanidins were found in the manteca bean. Three main anthocyanins have been found in the three “black” genotypes, mat black, 5-593 and dark brown violet. Preliminary identification of the anthocyanins indicates the presence of delphinidin, petunidin and malvidin. Further work on identification of the minor anthocyanins is underway.
The rp Allele Alters Carotenoid Accumulation and Composition in Carrot Roots
Authors: Poon W.Y.L. , Goldman I.L.
Published: February 2019

Previous studies have shown the lack of pigmentation in carrot root is dominant to the production of pigment. However, the rp allele causes a 92% reduction in total carotenoid pigmentation in roots of W266rprp. When homozygous recessive, the rp allele also appears to alter the carotenoid quality of carrot roots. The primary focus of this study was to investigate the effect of rp on the composition of carotenoids in two near-isolines of carrot, W266RPRP and W266rprp. Field experiments during 1996 and 1997 revealed that accumulation of total carotenoid concentration in W266RPRP and in W266rprp was 12.7 and 1.3 μg/g dry weight, respectively. HPLC analyses showed W266rprp contained no α-carotene, whereas W266RPRP contained both α- and β-carotene. HPLC analyses of W266rprp also showed no accumulation of phytoene nor lycopene and due to the absence of α-carotene in W266rprp, thus it was hypothesized that the rp gene may cause a lesion in the β and/or ϵ cyclases. HPLC analyses also provided evidence that the rp gene is associated with a greater synthesis of a product that has a high absorbance at 296 nm and an elution time ≈28.6 min in W266rprp. MALDI mass spectroscopy of HPLC-generated fractions eluting at 28.6 min revealed differences between W266rprp and W266RPRP, suggesting differential carotenoid composition between the two near-isolines.
Source–Sink Relations in Non-dormant and Dormant Blueberry Production Systems
Authors: Swain Peter A.W. , Darnell Rebecca L.
Published: February 2019

Two cultivars of southern highbush blueberry (Vaccinium corymbosum interspecific hybrid) were grown in containers under the traditional dormant production system or the non-dormant production system. Plants in the non-dormant production system were maintained by continuous N fertilization throughout the year. The first objective was to determine when source limitations to reproductive development in blueberry occurred. The second objective was to determine if source limitations could be alleviated by the non-dormant production system, since photosynthesis and therefore carbohydrate accumulation continue later into the season. In order to determine when source limitations occurred, reproductive manipulations were applied to three groups of plants, either after flower bud differentiation in the fall, or after fruit set in the spring. After flower bud differentiation, 80% of the flower buds were removed from one plant group. After fruit set, 80% of individual fruits or 80% of fruit clusters were removed from two other plant groups. Average fruit dry weight was higher in the flower bud removal treatment than in the fruit removal or control treatments in the dormant production system, indicating a source limitation occurs prior to anthesis. No pre-anthesis source limitation was found in the non-dormant system; this is probably due to insufficient fruit and flower removal, and/or continued flower bud initiation prior to anthesis in this system. However, both fruit number and total yield were significantly higher in the non-dormant than the dormant production system.
Consumer Perceptions of Plant Quality
Authors: Bilderback T.E. , Glasgow T.E. , Johnson T. , Perry K.B. , Safley C.D.
Published: February 2019

Plant quality has been identified as one of the most important factors in determining where retail customers shop and which plants they buy. A better understanding of what customers actually mean by “plant quality” can enhance the industry's ability to give customers what they want, and improve the competitive position of individual nursery/garden center businesses. Five common woody ornamentals—flowering dogwood (Cornus florida), red maple (Acer rubrum), azalea (Rhododendron spp.), nandina (Nandina domestica) and `Compacta' holly (Ilex crenata `Compacta')—were selected for a three-part study of consumer perceptions of plant quality. The first component of the study was comprised of three focus groups, conducted during Summer 1995 in New Bern, N.C., and Fall 1996 in Raleigh, N.C. The purpose of the focus groups was to learn more about the specific quality attributes customers use in evaluating trees and shrubs in the garden center. The second component consisted of five different intercept surveys conducted in 1997 and 1998 in Virginia, North Carolina, South Carolina, Florida, Georgia, Alabama, and Tennessee. Purchase intent, rank order, paired comparison, dollar metric and constant sum scales, accompanied by photographs of plant material, were used to interview retail customers in independently-owned garden centers. These studies focused primarily on azaleas and dogwoods. The third component was a hedonic study focusing on azaleas and `Compacta' holly, conducted in the Raleigh, N.C., area in Apr. 1998. Using standard regression analysis techniques, hedonics examines prices and levels of selected attributes to provide an estimate of the marginal implicit price a consumer is willing to pay for an additional unit of a particular attribute.
Resistance to Lettuce Infectious Yellows Virus in Melon
Authors: McCreight James D.
Published: February 2019

Yellowing of melon (Cucumis melo L.) incited by lettuce infectious yellows virus (LIYV) reduces yield and fruit quality of infected plants. LIYV is transmitted only by the sweetpotato whitefly (Bemisia tabaci Genn.). Two naturally infected field tests indicated several potential sources of resistance to LIYV. PI 124112 and `Snake Melon' had mild symptoms in both field tests whereas PI 313970 was asymptomatic in the test in which it was included. In greenhouse tests using controlled inoculation, PI 313970 was asymptomatic, had negative ELISA assays for LIYV, and was negative for LIYV in serial transfers to Chenopodium. `Top Mark' and `PMR 5' were symptomatic, had positive ELISA assays for LIYV, and were positive for LIYV in serial transfers to Chenopodium in these greenhouse tests. Limited data indicate that resistance in PI 313970 is conditioned by a single, dominant gene.
Floral Ontogeny of Pelargonium × domesticum
Authors: Loehrlein Marietta M. , Craig Richard
Published: February 2019

Floral ontogeny of Pelargonium xdomesticum was examined for two cultivars grown under identical environmental conditions. Apical meristems of `Duchess' and `Jennifer' were vegetative at the commencement of the experiment. Meristems were examined every five days over an experimental period lasting 85 days. Floral ontogeny was the same for both cultivars, although the timing of floral initiation of the meristem, floral organ initiation, and floral organ development differed. The vegetative meristem was convex with leaf primordia initiated on either side in an alternate pattern. Early floral initiation was characterized by formation of a cleft towards one side of the meristem, followed quickly by a second cleft on the other side. Between the clefts new meristems developed. New meristems lacked leaf primordia. Proliferation of meristems continued until numerous meristems were organized in a cluster arrangement at the apex of the shoot. Proliferation of meristems at the apex continued until multiple inflorescences had developed. Inflorescences were subtended by bracts. Floral organ primordia were initiated in a succession of four whorls: sepals, petals, androecia and gynoecium. Petals and androecia appeared to develop simultaneously soon after sepal primordia were visible. Petal primordia remained small while the androecia continued to grow. The gynoecium first formed a conical shape, with carpels protruding from the base in a bulbous fashion. At the distal end of the gynoecium, divisions appeared which developed into stigmatic lobes. As the gynoecium elongated, stigmatic lobes became more pronounced. Petal elongation concurred in synchrony with elongation of the gynoecium. On one experimental unit of `Duchess' two florets had opened at 750 total cumulative moles. No `Jennifer' florets had opened by termination of the experiment.
Factors Influencing Strawberry Plug Plant Performance
Authors: Crawford T.D. , Himelrick D.G. , Sibley J.L.
Published: February 2019

Three studies evaluating production of strawberry (Fragaria × ananassa Duch.) plug plants were conducted. The influence of runner tip plantlet size, container size, and chilling on the field performance of `Chandler' plug plants were evaluated over a 2-year period in central and southern Alabama. Plantlet size did not significantly influence yield following transplanting; therefore, grading of plantlets prior to propagation appears to be an unnecessary expense for successful yields from plug plants. There were no significant differences in yields of plug plants from 60-cell vs. 72-cell packs; therefore, growers could produce more plug plants in the same area without compromising total yield, early yield, or berry size when propagating plug plants in 72-cell packs. The influence of 1, 2 or 3 months of runner tip cold storage prior to rooting in cell packs was also investigated.
Soil Moisture and Soil Salinity Distribution in Strawberry Beds
Authors: Bendixen W.E. , Hanson B.R.
Published: February 2019

Strawberries in the Santa Maria Valley are grown on beds 25.2 cm wide with four rows of strawberries and two lateral drip tapes. Previous strawberry production was on beds 15.7 cm wide with two rows of strawberries and one lateral drip tape. The two strawberry production systems were evaluated on several grower fields for water emission uniformity, soil moisture, and soil salinity. The salinity was evaluated for placement in the bed, type of salts, and nitrate concentration. At one side, the effect of banded slow-release nitrogen fertilizers as a source of nitrogen in addition to that applied through fertigation was investigated. Results showed that the EUs ranged between 80% and 96%, with an average of 89%. A variety of distributions were found for soil moisture, soil salinity, and soil nitrate, depending on the water and fertilizer management and time of sampling with respect to irrigation and fertigation. Distributions of soil moisture content made 3 to 4 days after an irrigation indicated excessive drying of the soil between irrigations. Distributions of soil salinity revealed high salt concentrations near the drip tape, where leaching was insufficient, and relatively low concentrations near the tape, where leaching was adequate. Nitrate concentrations in and below the rootzone were smaller where no slow-release fertilizers were used.
Transplanting Shock and Water Relations in Urban Tree Species
Authors: Barton Amy J. , Walsh Christopher S.
Published: February 2019

Large-caliper trees transplanted into urban settings show low survivability. A 1-year transplanting experiment was conducted using Acer ginnala and Acer truncatum. Trees were blocked by species and size, with three blocks of four trees per species. Three trees of each species were left in their original location for purpose of comparison. A 2 × 2 factorial was used to assign treatments (water, water and top prune, top prune, and transplanted control). Using a Schollander Pressure Bomb, predawn and midday water potential measurements were recorded biweekly from early May through September. The first 8 weeks following transplant, all transplanted trees of both species had significantly (P ≥ 0.05) more negative midday water potentials than those not transplanted. During periods of stress, predawn water potentials of transplanted trees did not recover overnight. By September, irrigated trees had water potentials not significantly different from those of trees not transplanted. Canopy closure was measured on the same schedule using a Li-Cor Canopy Analyzer. Leaf area index of transplanted trees was nearly half that of non-transplanted trees. Trees treated with water did have slight, but significantly greater leaf area indexes than those of other treatments. It appears that the most notable effect of transplanting is the inhibition of leaf expansion resulting from early spring water stress. This leads to an open canopy for the whole season following transplant.
Leaf Gas Exchange and Growth Responses of Young, Container-grown Annona Trees to Flooding
Authors: Núñez-Elisea Roberto , Schaffer Bruce , Crane Jonathan H. , Colls Angel M.
Published: February 2019

Commercial Annona species such as sugar apple and atemoya, are sensitive to flooding. Annona glabra (pond apple) is a non-commercial species that grows well in flooded soils and may have potential as a flood-tolerant rootstock for commercial Annonas. The effects of flooding on net CO2 assimilation (A), stomatal conductance (gs), and vegetative growth of 2-year-old, container-grown Annona trees were studied under glasshouse conditions. Seedlings of A. glabra, A. muricata, and A. squamosa, and plants of `49-11' [a cross between atemoya (Annona. spp. hybrid cv. Gefner) × A. reticulata] grafted onto A. glabra or A. reticulata rootstock (`49-11'/A. glabra; `49-11'/A. reticulata) were exposed to 50 days of continuous flooding. Non-flooded (control) plants were irrigated daily. Flooded soil became anaerobic from day 3 of initiating the flooding treatment. Seedlings of A. glabra and A. muricata, and trees of `49-11'/A. glabra, produced more vegetative growth during flooding than A. squamosa and `49-11'/A. reticulata. Flooding decreased A and gs of A. squamosa and `49-11'/A. reticulata, and caused tree mortality (80%) of A. squamosa. Morphological adaptations of A. glabra (seedlings and rootstock) to flooding included adventitious root formation into flood water, development of hypertrophied (swollen) lenticels on trunk and adventitious roots, and development of trunk aerenchyma. All seedling trees of A. glabra and A. muricata, and all grafted trees of `49-11'/A. glabra survived 120 days of continuous flooding. A. glabra rootstock imparted flood tolerance to the `49-11' scion and may therefore impart flood tolerance to other Annona species. A. muricata seedlings may withstand extended periods of waterlogging under field conditions.
Flower Development and Yield of Cucurbita in Four Locations Differing in Temperature
Authors: Wien H.C. , Cady S. , Maynard D.N. , McClurg C. , Riggs D.
Published: February 2019

Preliminary greenhouse experiments indicated that Cucurbita pepo, when grown at high temperatures, shows a high incidence of female flower bud necrosis, preventing those flowers from reaching anthesis and thus delaying fruit set. This can lead to reduced yield in areas with short growing seasons. To determine if delayed fruit set also occurred under field conditions, replicated cultivar trials were conducted during the summer seasons of 1996 and 1997 in Ithaca and Albany, N.Y.; Wye, Md., and Bradenton, Fla. Mean growing season air temperatures were 20, 21, 24, and 28 °C, respectively, at the four locations. Delay in fruit set was indicated by the main stem node number at which the first fruit formed. In Ithaca and Albany, the six cultivars grown in both years formed their first fruit at node 17, while this was shifted to node 24 at Wye, and to node 26 or more at Bradenton. Fruit yields among the C. pepo cultivars ranged from 45 to 85 mt·ha–1 in all locations except Bradenton, where they ranged from 7 to 35 tons. Among C. pepo cultivars, `Appalachian' showed least yield decrease at Bradenton, and `Howden' and `Baby Bear' the most, in the hotter 1996 season. The C. maxima `Prize Winner' yielded well in all locations. The results indicate that delayed fruit set occurred most often in the highest temperature locations. There is scope for selecting for improved high temperature female flower development among C. pepo cultivars.
Distribution of Glucosinolates and Myrosinase Activity in Cruciferous Vegetables
Authors: Kushad M. , Brown A. , Baik H.-Y. , Kurilich A. , Juvik J. , Wallig M. , Klein B. , Jeffery E.
Published: February 2019

A diet rich in curciferous vegetables has been associated with inhibition of chemically induced carcinogenesis in laboratory animals and humans. The underlying mechanism(s) for this inhibition is not completely clear; however, cruciferous vegetables are rich in sulfur-containing glucosides called gluco-sinolates. Myrosinase-mediated breakdown of glucosinolates has been shown to produce compounds with anti-cancer activity. About 100 forms of glucosinolates have been identified, mostly in the Cruciferae family. In this study, we have developed a unique data set of glucosinolate types and amounts in 51 broccoli, three cauliflower, five Brussels sprouts, five cabbage, and two kale lines. The types of glucosinolates and their concentrations were variable among the different genotypes and within each genotype. The dominant glucosinolates in broccoli were glucoraphanin, gluconapin, and glucobrassicin. Glucoraphanin concentration in broccoli ranged from 0.1 μmol·g–1 dry weight in EV6-1 to 21.7 μmol·g–1 dry weight in Brigadier. Concentrations of the other types of glucosinolates in broccoli also showed wide range of variability. In cabbage, Brussels sprouts, cauliflower, and kale, the dominant glucosinolates were sinigrin (7.8, 8.9, 9.3, and 10.3 μmol·g–1 dry weight, respectively) and glucobrassicin (0.9, 3.2, 1.3, and 1.2 μmol·g–1 dry weight, respectively). Brussels sprouts also has significant amounts of gluconapin (6.8 μmol·g–1 dry weight). Myrosinase activity, using sinigrin as substrate, was significantly higher in cabbage, Brussels sprouts, cauliflower, and kale than in broccoli. Wide variations in glucosinolates, glucosinolates content, and myrosinase activity among cruciferous genotypes and within each genotype suggest differences in the health-promoting properties of these vegetables.
Germination Response of `Genesis' Triploid Watermelon [Citrullus lantaus (Thunb.) Matsum & Nakai] to Hydrogen Peroxide and Seed Coat Alteration
Authors: Duval John R. , NeSmith D. Scott
Published: February 2019

Triploid watermelons are fast becoming a highly desirable specialty crop. Poor germination and nonuniform emergence of the relatively expensive seed prohibits to many potential growers. Improvement of germination and emergence of triploid watermelons would reduce overall risk to a grower, thus increasing the crops market prominence. Seeds of `Genesis' triploid watermelon were subjected to three treatments: 1) seed coat removal; 2) clipping the seed coat opposite the radicle end, and 3) no seed coat alteration. Seeds from each treatment were germinated on agar alone or in the presence of 5 ml of a 1%, 2%, 4%, or 8% solution of H2O2. Test were conducted in a constant temperature (28 °C) growth chamber in the dark. Seed coat removal, clipping, and all levels of H2O2 increased final germination percentages relative to the control. Germination differences as great as 70% occurred. Hydrogen peroxide levels greater than 2% resulted in severe injury to germinating seeds.
Detection and Mapping of RAPD Markers Associated with QTL Affecting Seed Size and Shape in Common Bean
Authors: Park Soon O. , Coyne Dermot P. , Jung Geunhwa , Arnaud-Santana E. , Ariyarathne H.
Published: February 2019

Seed size is an important trait in common bean. The objective was to identify RAPD markers associated with QTL for seed weight, seed length, and seed height in a molecular marker-based linkage map in a recombinant inbred (RI) population from the common bean cross of the larger seeded (100 seed/39 to 47 g) PC-50 (ovate seed shape) × smaller seeded (100 seed/26 to 35 g) XAN-159 (flat rhomboidal seed shape). The parents and RI lines were grown in two separate greenhouse and two field (Wisconsin, Dominican Republic) experiments using a RCBD. Continuous distributions for seed weight, seed length, and seed height were observed for RI lines indicating quantitative inheritance. One to three QTLs affecting seed weight explained 17% to 41% of the phenotypic variation. Two to three QTLs for seed length explained 23% to 45% of the phenotypic variation. One to four QTL associated with seed height explained 17% to 39% of the phenotypic variation. A RAPD marker M5.850 in linkage group 3 was consistently associated with seed weight, seed length, and seed height in all experiments and explained 7% to 13% of the phenotypic variation for these traits. A seedcoat pattern morphological marker (C) in linkage group 1 was associated with seed weight and seed height in two greenhouse experiments.
Long-term Performance of Asian Pear Trees in Maryland
Authors: Walsh C.S. , Barton A.J. , Newell M. , Welsh G.R.
Published: February 2019

Three Asian pear plantings were set during the past decade. Plantings included an initial cultivar planting on OH × F rootstock, the SE Zonal planting, and a rootstock by cultivar factorial. Fireblight susceptibility and survival were assessed in the first two plantings following a summer hailstorm. Trees were compared to Magness, a blight-tolerant buttery pear. Shin Li, Daisu Li, Shinsui, and Olympic were more resistant than Magness, while Chojuro and Niitaka were nearly as tolerant. Eleven other cultivars showed greater field-susceptibility. The most-susceptible cultivars were Ya Li and Ts'e Li. The third planting, which was managed “organically,” was set at a different University farm. Trees there were precocious and productive. A high percentage of marketable fruit was picked from that planting over a 4-year period. Fireblight damage in this planting was low, despite its “organic” production. Limited damage was attributed to early bloom date, ground cover management, and a lack of insect vectors to transmit the bacteria. Hosui, Seuri and Ts'e Li produced large-sized fruit. Shinko, 20th Century, Ya Li and Shinseiki fruit were too small to be marketable without heavy hand-thinning. Asian pears are an interesting alternative crop which are suited to direct-market enterprises or to specialty growers interested in producing organic fruit in the mid-Atlantic region.
Picking Regimes Affect Yield, Grade Distribution and Retail Value of Colored Bell Pepper
Authors: Simonne Eric H. , Owen John T.
Published: February 2019

The retail value of yellow and red bell peppers is usually three to five times higher than that of the green ones. However, colored bell pepper production in Alabama is presently limited because most growers do not wait the additional 3 to 6 days needed for marketable green pepper to develop color. Hence, drip-irrigated yellow `Admiral' and `Goldcoast' and red `Bell Star' and `Capsitrano' bell peppers were grown in single row and bare-ground, and harvested as needed between July and October 1997 at the 0/3 (green), 1/3 or 2/3 colored stages. The interaction variety × picking method was not signficant (P > 0.50). Early (9,136 kg/ha) and total (32,363 kg/ha) yields of green (0/3) peppers were significantly (P < 0.05) higher than those of the 1/3 and 2/3 colored ones (5,166 and 27,235 kg/ha, respectively). Higher green yields were mainly due to increased numbers of marketable fruits rather than increased fruit size. The longer the pods stayed on the plants, the more likely was sunscald to occur. Retail values (/ha) for the early fancy grade were $10,800 and $20,500 for the green and colored peppers, respectively (using $2 and $6/kg, respectively). These results suggest that the present higher retail value of the colored bell peppers off-sets the lower expected yields.
Enhancing Early Maturity in Processing Tomatoes with the Use of Ethephon
Authors: Murray Mike
Published: February 2019

Ethephon is a tool that has been widely used to advance maturity in processing tomatoes. However, it's use has largely been restricted to mid- or late-season applications, due to concerns about the chemical's stability and resultant phytotoxicity if hot ambient air temperatures occur during or immediately following applications. Four years of tests evaluating decreased rates of ethephon have been conducted in commercial processing tomato fields. Each test included 10–15 early season cultivars. Fruit quality, maturity and yield were evaluated. In all cases, ethephon rates of 1–1.5 pints of product per acre resulted in maturity enhancements of 8–15 days, compared to paired untreated control plots. There were no adverse effects on fruit soluble solids, color or yield. Industry adoption of this technology has provided a tool to increase acreage by spreading production over a longer period of time and maintain harvest schedules that are adversely impacted by cool weather or replanting.
The Development of ASHS HortBase—A Global Information System
Authors: Green James L.
Published: February 2019

In 1997, the ASHS Board of Directors established ASHS HortBase as a Standing Committee of the Society. The ASHS HortBase Committee, a six-member Standing Committee and Chair, is charged to implement and maintain ASHS HortBase. The members of the ASHS HortBase Committee will be chair and chair-elect of the three HortBase Task Forces: 1) Finance and Marketing; 2) Standards—authoring, reviewing, and publishing; and 3) Technology. ASHS HortBase is a dispersed, dynamic horticultural information system (network) on the WWW comprised of peer—reviewed, concise, interlinked information modules to meet the information needs of instructors and students, gardeners and growers. A strong advantage and distinguishing characteristic of ASHS HortBase is our dynamic pool of potential authors, reviewers, and users (ASHS Extension, Industry, and Teaching membership) to continually evolve and update the peer-reviewed information in HortBase. We have the scholastic international standing to provide peer review and validation of the information and to recognition to the authors, coupled with the marketing to stimulate wide use of their information modules. ASHS HortBase is a dispersed system (dispersed development and server costs). The “dispersed cost” for information file development and updating and delivery on the respective authors' dispersed servers disperses the major costs of the HortBase information system. Additional information on ASHS HortBase and the papers presented at the 4-h Colloquium on HortBase at ASHS-97 can be found at http://hortbase@ashs.org or contact me (greenjl@bcc.orst.edu, phone 541.737.5452, fax 541.737.3479).
Pedigree and Pedigree Import Wizard
Authors: Khandizadeh Shahrokh
Published: February 2019

Pedigree for Windows is a user-friendly program that allows the user to trace agronomic characteristics, draw pedigrees, and view images of several fruit crops, including more than 1400 apple, 800 strawberry, 800 almond, 100 blackberry, 80 blueberry, 790 pear, 200 raspberry examples. Pedigree Import Wizard®© for Windows is an add-on software for users who are interested in importing their research or breeding data records of fruit, flower, and plant characteristics and any related images into Pedigree for Windows. Pedigree for Windows and Pedigree Import Wizard have been designed so that a user familiar with the Windows operating environment should have little need to refer to the documentation provided with the program. Pedigree Import Wizard uses a comma-separated value (csv) file format under the MS Excel environment. This option allows the user to add or import additional data to the existing database that are already stored in other software such as Lotus, Excel, Access, QuattroPro, WordPerfect, and MS Word tables, etc., as long as they work under the Windows environment. A free demo version of Pedigree and Pedigree Import Wizard for Windows is available from http://www.pgris.com.
Spray Volume, Canopy Density, and Other Factors Involved in Thinner Efficacy
Authors: Unrath C.R.
Published: February 2019

Historically, most airblast chemical applications to apple orchards used a single “average” water volume, resulting in variability of coverage with tree size and also the greatest variable in chemical thinning. This coverage variability can be eliminated by properly quantifying the tree canopy, as tree row volume (TRV), and relating that volume to airblast water rate for adequate coverge. Maximum typical tree height, cross-row limb spread, and between-row spacing are used to quantify the TRV. Further refinement is achieved by adjusting the water volume for tree canopy density. The North Carolina TRV model allows a density adjustment from 0.7 gal/1000 ft3 of TRV for young, very open tree canopies to 1.0 gal/1000 ft3 of TRV for large, thick tree canopies to deliver a full dilute application for maximum water application (to the point of run-off). Most dilute pesticide applications use 70% of full dilute to approach the point of drip (pesticide dilute) to not waste chemicals and reduce non-target environmental exposure. From the “chemical load” (i.e., lb/acre) calculated for the pesticide dilute application, the proper chemical load for lower (concentrate) water volumes can be accurately determined. Another significant source of variability is thinner application response is spray distribution to various areas of the tree. This variability is related to tree configuration, light, levels, fruit set, and natural thinning vs. the need for chemical thinning. Required water delivery patterns are a function of tree size, form, spacing, and density, as well as sprayer design (no. of nozzles and fan size). The TRV model, density adjustments, and nozzle patterns to effectively hit the target for uniform crop load will be addressed.
Effects of Nutritional Factors on Regular Cropping of Apple
Authors: Stiles Warren C.
Published: February 2019

Any mineral nutrient deficiency or toxicity that adversely influences the normal biochemical and physiological processes in the tree can be expected to impact regularity of cropping. Deficiency of N limits growth and flowering of young trees and increases potential for biennial bearing in mature trees while excess N may stimulate excessive vegetative growth that results in shading of spurs and development of weak flowers with reduced set potential. B, Zn, and Cu shortages influence regularity of cropping through effects on flower development, pollination and/or fertilization. Effects of K, Mg, Mn, Fe, or S appear to be indirect, principally as consequences of limited carbohydrate production/availability. Crop load/vegetative growth relationships in one season can exert significant influences on nutrient status within the tree that may influence potential for cropping in the next season. Environmental stress may limit nutrient availability of various nutrient elements at critical times during the flower development and fruit setting sequence. Effects of nutritional factors on regularity of cropping must be considered in relation to their interaction with all other components of the fruit production system. Maintaining appropriate essential mineral nutrient supply and availability to avoid potential deficiencies or toxicities is critical to regular cropping of apple trees.
Hazelnut Pollination
Authors: Olsen J.L. , Mehlenbacher S.A. , Azarenko A.N.
Published: February 2019

Hazelnuts are wind-pollinated, monoecious, mostly dichogamous, and self-incompatible of the sporophytic type. About 90% of the cultivars studied are protandrous. Anthesis of the pistillate flower is temperature-dependent and occurs from December through February, with its peak in January. Stigmatic surfaces may remain receptive for up to 3 months. Four to 5 months separate pollination and fertilization of the ovule, which usually occurs between mid-May and the end of June in Oregon. A 10% pollinizer density has been the standard, with a recommended distance of <20 m between the main cultivar and the nearest pollinizer. Two or three different pollinizer varieties with different times of pollen shed are recommended. The Oregon hazelnut industry is presently combating the fungal disease, Eastern Filbert Blight, Anisogramma anomala. Part of the current management recommendations are to reduce the susceptible pollinizer varieties to a density of around 5%, and then gradually replace those left with immune or more-resistant genotypes. Recent research by S.A. Mehlenbacher refined methods of using fluorescense microscopy to quickly determine genotype compatibility. The self-incompatiblity is controlled by a single gene with multiple alleles. The biochemical, physiological, and molecular aspects of sporophytic self-incompatiblity are being research by A.N. Azarenko.
Effects of Polyethylene Glycol on Development of Grape (Vitis vinifera L. `Thompson Seedless') Somatic Embryos
Authors: Westphal Fred K. , Compton Michael E.
Published: February 2019

Torpedo-stage somatic embryos were selected from actively growing cultures and trasferred to embryo maintenance medium [MS with (per liter) 412.5 mg NH4NO3, 475 mg KNO3, 1 g myo-inositol, 90 g sucrose, 2 g activated charcoal, and 7 g TC agar] supplemented with either 0%, 2.5%, 5%, 7.5%, or 10% polyethylene glycol (PEG) for 4, 8, or 12 weeks. Embryos placed on treatment media were transferred directly to grape somatic embryo germination medium [MS with (per liter) 1 g myo-inositol, 30 g sucrose, 1 M benzyladenine, and 7 g TC agar] once their PEG treatment was terminated. The number of embryos that germinated was recorded 4 weeks after transfer to somatic embryo germination medium. The number of germinated embryos that differentiated into plants was recorded at 8 weeks. There was no difference in germination rates and embryo differentiation among embryos incubated on medium with or without PEG for 4 weeks. A difference in embryo growth rate was observed after 8 weeks on medium with PEG. Embryo grew fastest on media containing 5% or 7.5% PEG. In addition, embryos grown on medium with 5% or 7.5% PEG were morphologically similar to zygotic embryos.
Coordinating Sustainable Landscapes for a Low-income Community
Authors: Reed Joshua H. , Haque Mary T.
Published: February 2019

The City of Clemson, along with the National Wildlife Federation, Habitat for Humanity, and Clemson Univ., recently formed a strategic alliance to incorporate ideas for the landscaping of low-income homes. Their goal was to create an aesthetically pleasing, environmentally responsible design that catered to the future development of the families involved. The low-income housing project was selected as an independent study for Spring 1998. As student project manager I coordinated and documented the project. Objectives of the project were: 1) to promote knowledge and research on environmental issues and culturally diverse populations; 2) to create backyard wildlife habitats and sustainable community environments for low income families; 3) to provide students with the opportunity to learn and mature by participating in a long-term project involving a measurable impact. Project steps included analysis, research, design, planning, scheduling, implementation, and reflection on the impact made by those involved. The City of Clemson, along with the others involved, was delighted to be the first to address the issue of enhancing open space around low-income buildings in addition to landscaping the properties surrounding the homes.