bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vitro Response of Strawberry Cultivars and Somaclones to Colletotrichum acutatum
Authors: Hammerschlag* Freddi A. , Garces Sandra , Koch-Dean Margery , Ray Stephanie , Lewers Kim S. , Maas John L. , Smith Barbara J.
Published: February 2019

Diseases affecting strawberries have been of major concern in recent years because of their widespread occurrence and potential for yield loss. Anthracnose caused by the fungus Colletotrichum acutatum is one of the most serious disases of strawberry worldwide. Although chemical controls are being used to treat anthracnose, generating disease resistant plants is a more attractive solution to the problem because chemicals can pose a health hazard, have a negative impact on the environment and may only be moderately effective. Tissue culture-induced (somaclonal) variation provides us with one strategy for generating disease-resistant genotypes. An in vitro screening system was used to evaluate several commercially important cultivars, Chandler, Delmarvel, Honeoye, Latestar, Pelican and Sweet Charlie, and shoots regenerated from leaf explants of these cultivars for resistance to C. acutatum isolate Goff (highly virulent). Somaclones with increased levels of anthracnose resistance were identified for all the cultivars. The greatest increases in disease resistance were observed for somaclones of cultivars Chandler, Pelican and Sweet Charlie that exhibited 6.8-, 12-, and 4.2-fold increases in resistance, respectively. These studies provide evidence that: 1) in vitro screening can be used to evaluate strawberry germplasm for anthracnose resistance, 2) soma-clonal variation is influenced by stawberry genotype, and 3) generating somaclonal variants may be a feasible approach to obtaining strawberry plants with increased levels of anthracnose resistance.
Phloem Loading of Sorbitol in Apple (Malus domestica Borkh.): Cloning and Sequence Analysis of Potential H+/Sorbitol Symporters from a Mature Leaf cDNA Library
Authors: Reidel* Edwin J. , Ayre Brian G. , Turgeon E. Robert , Cheng Lailiang
Published: February 2019

Sorbitol (d-glucitol) is the major end product of photosynthesis in apple (Malus domestica Borkh.), as well as the predominant phloem-translocated carbohydrate. The mechanism by which sorbitol is phloem-loaded for transport to heterotrophic sink tissues is unknown. We hypothesized that a plasma membrane-bound H+/sorbitol symporter mediates apoplastic phloem-loading of sorbitol. To discover genes potentially encoding sorbitol transporters, a cDNA library was constructed from mature `Gala' apple leaves. A homologous probe was synthesized via PCR with primers were designed against the cherry fruit sorbitol transporter, PcSot1, and using library lysate as template. From an initial plating of approximately 5 × 105 clones, twelve positives were identified after three rounds of hybridization screening. Following single-pass, 5' end sequencing, the clones were sorted into four contiguous sequences. One clone was chosen from each contig for complete sequencing. The four clones, provisionally named MdSOT1-4 (Malus domesitca Sorbitol Transporter), potentially encode full-length cDNAs for sorbitol transporters: Translated-BLAST searching (blastx) revealed that the open reading frames encode the complete Pfam sugar transporter domain, and the most significant alignments are with sequences encoding known- and putative polyol and sugar transporters.
Preliminary Pathogenesis-relative Pathways Network Analysis and Relative Putative Genes Annotation In Vitis shuttleworthii Grape through EST Analysis
Authors: Lu* Jiang , Huang Hong , Hunter Wayne , Dang Phat , Leong Stephen
Published: February 2019

Vitis shuttleworthii is one of the most disease and pest resistant grape species originated and distributed in the southeast United States. It is highly resistant to Pierce's disease, anthracnose, black rot and downy mildew diseases, which are the limited factors to grow Vitis vinifera grapes in this region. A V. shuttleworthii cDNA library was constructed with mRNA isolated from leaves and flowers harvested during anthesis. 12,008 clean EST sequences were obtained and assembled. and generated 5776 unigenes 2106 contigs and 3670 singletons). ESTs distribution based on protein function using a modified MIPS MATDB Arabidopsis Scheme revealed that 7% of the V. shuttleworthii ESTs were related to disease/pest defense or stress tolerance genes. Over 300 contigs containing complete or 90% open coding region of known functional genes were obtained. The ESTs that were annotated as pathogenesis-related proteins, enzymes in salicylic acid, jasmonic acid, and ethylene signaling, were selected for further study in order to elucidate the role and interaction of them in the signal transduction cascade that leads to grape defense gene activation upon treatment of bacterial pathogen. We report the identification of novel disease resistant genes based on preliminary pathogenesis-relative pathways network analysis.
Producing Double-stemmed Tomato Seedlings by Cutting Propagation, Pinching, and Plant Bioregulators Application
Authors: Jung* Ki-Yun , Kang Bong-Hwa , Park Yu-Jin , Lee Jung-Myung
Published: February 2019

Double-stemmed seedlings (DSS) will be favored by the growers because they can save the expense needed to purchase commercial seedlings. This is also true with grafted tomatoes since the price of grafted tomato seedlings is about 2 times higher than non-grafted ones. The plug seedling growers will also benefit from the increased demand for DSS if the production cost for DSS can be maintained at appropriate level. Two stem cuttings having two expanded leaves were taken from a seedling when the seedling had four expanded leaves and rooted in 32-cell trays filled with commercial soil mix. Lower stem cuttings having first and second leaves produced well-balanced DSS even without any plant bioregulator treatment whereas up upper stem cuttings having third and fourth leaves resulted in single-stem seedlings with very limited outgrowth of axillary shoot from the third node. DSS can be obtained from the decapitated seedling stump by outgrowth of axillary shoots from the cotyledonary nodes, but the quality and uniformity were inferior to other seedlings. Pinching off the tips of seedlings thus leaving three expanded leaves per seedling and application of plant bioregulators to the decapitated seedlings were also effective for producing DDS. Application of thidiazuron (TDZ) in lanolin paste to the second node was most effective even though whole plant spray with TDZ or BA was also partially effective. Subsequent growth characteristics of these seedlings will be further discussed.
Ethylene Biosynthesis and Fruit Color Development in `Pink Lady' Apples during Growth and Maturation
Authors: Whale* Suparna , Singh Zora , Janes John
Published: February 2019

Growth and maturation of `Pink Lady' (Malus domestica Borkh.) apples with special emphasis on ethylene biosynthesis and color development were monitored in Western Australia during 2002-2003. Changes in fruit growth, respiration rate, ethylene production, anthocyanin accumulation and development of red blush were evaluated between 60 days after full bloom (DAFB) and commercial harvest (191DAFB). Fruit diameter, length and fresh weight showed the typical single sigmoid growth curve, with linear increases until 158 DAFB. High respiration rate and ethylene production were recorded 60 DAFB followed by rapid decrease until 144 DAFB and then a steady increase, which peaked between 172 and 179 DAFB. Red blush on the fruit surface showed steady increase from 167 DAFB and corresponded to concomitant decrease in hue angle. Total anthocyanin increased from 167 DAFB till harvest and synchronized with increasing ethylene and maturity of apples. There were significant (P ≤ 0.001), direct linear relationships between ethylene production and total anthocyanin (r = 0.63, y = 7.6032x + 2.4756), total anthocyanin and red blush (r = 0.74, y = 0.5082x -1.54). Significant (P ≤ 0.001) negative direct linear relationships between total anthocyanin and hue angle (r = -0.89, y = -0.5973x + 110.14), and ethylene and hue angle (r = -0.69, y = -5.37x + 109.60) were recorded. Increasing anthocyanin content and red blush also coincided with decreasing daily temperatures in the orchard. Reduction in fruit firmness and acidity and increase in TSS from 167DAFB were good indicators of advancing maturity of apples. Our experimental results indicate that red blush in `Pink Lady' apples develops a few weeks before harvest and is regulated by ethylene biosynthesis and temperature.
Mycorrhiza-induced Changes in Partitioning and Composition Alters Flower and Vegetative Production of Floral Geophytes
Authors: Scagel* Carolyn
Published: February 2019

Resource partitioning and plant storage components are important factors that influence the productivity and profitability of geophyte species produced as floral crops. We determined that inoculation with arbuscular mycorrhizal fungi (AMF) can alter different plant characteristics affecting productivity and quality of bulb and cut flower production of several floral geophytes including Brodiaea laxa, Zephyranthes sp., Sparaxis tricolor, Freesia × hybrida, Zantedeschia sp., and Canna sp. Plant growth, flower production, bulb/corm/tuber (bulb) production and composition were measured for two growth cycles after inoculation with Glomus intraradices. In general, shoots and flowers on plants inoculated with AMF emerged earlier than shoots and flowers on non-inoculated plants for species that produced most of their leaf area prior to flower emergence. However for species that produced leaves throughout the growth cycle or large flowers early in the growth cycle, AMF inoculation delayed shoot emergence and flower emergence. Many species that exhibited an earlier flower emergence or produced more flowers in response to AMF inoculation also produced smaller daughter bulbs and more offsets than non-inoculated plants. Across all species, the concentrations and contents of several storage components (Zn, S, and N, amino acids, and carbohydrates) that influence bulb quality were increased by AMF inoculation. Changes in partitioning between bulb and flower production resulting from AMF inoculation altered important aspects of commercial geophyte production for flowers or bulbs. AMF-induced increases in mineral uptake and resource storage are also related to aspects of quality important in the production of vegetative propagates.
Absorption of Nutrient Elements on Single-node Cutting Rose `Versillia' as Affected by Mineral Nutrient Control in a Closed Hydroponic System
Authors: Yang* Eun Young , Lee Hye Jin , Lee Yong-Beom
Published: February 2019

The application of a closed hydroponic system for rose poses some horticultural problems. The nutrient uptake by the plants changes constantly depending upon environmental conditions and growing stages, which results in the imbalanced composition of the drained solution and aggravates root environmental conditions. This research was aimed to observe the effect of mineral nutrient control method on the nutrient solution management in a closed hydroponic system. Single-node cutting rose `Versillia' was grown in aeroponics and DFT system and was irrigated with the nutrient solution of the Univ. of Seoul (NO3 -N 8.8, NH4 -N 0.67, P 2.0, K 4.8, Ca 4.0, and Mg 2.0 me·L-1). Recirculated nutrient solution was managed by five different control method: macro- and micro-element control in aeroponic system (M&M); macroelement control in aeroponic system (M); nutrient solution supplement in aeroponic system (S); electrical conductivity (EC) control in aeroponic system (EC-A); EC control in deep flow technique system (EC-D). In the EC control method, the concentration of NO3 -N exceeds optimal range whereas P and Mg decreased at the later stage of plant growth. The overall mineral nutrient content increased with S. On the other hand, the nutrient content of root environment was maintained optimally with M&M and M.
The Assessment of Ozone Treatment for Control of Fungal Diseases of Floriculture Crops in Greenhouses and Cold Storages
Authors: Skog* Lisa J. , Blom Theo , Brown Wayne , Murr Dennis , Chu George
Published: February 2019

Ozone treatment has many advantages for control of fungal diseases. There are no residue concerns, no registration is required, and it is non-specific, therefore potentially effective against a broad spectrum of pathogens. However, ozone is known to cause plant damage. There is little information available on either the ozone tolerance of floriculture crops or the levels required to kill plant pathogens under commercial conditions. Nine floriculture crops (begonia, petunia, Impatiens, Kalanchoe, pot roses, pot chrysanthemums, lilies, snapdragons and Alstroemeria) were subjected to increasing levels of ozone. Trials were conducted at 5 and 20 °C (90% to 95% RH) and ozone exposure was for 4 days for either 10 hours per day (simulating night treatment) or for 10 minutes every hour. Damage was assessed immediately after treatment and after an additional 3 days at room temperature in ozone-free air. Trials were terminated for the crop when an unacceptable level of damage was observed. Trials to determine the lethal dose for actively growing pathogens (Alternaria alternata, Alternaria zinniae and Botrytis cinerea) and fungal spores were conducted under identical conditions. Ozone tolerance varied with plant type and ranged between <0.2 and 3ppm. Generally, the crops surveyed were more susceptible to ozone damage at the low temperature. As a group, the bedding plants were the least tolerant. Fungal spores were killed at treatment levels between 0.8 and 2 ppm ozone. The actively growing fungal mycelium was still viable at 3 ppm ozone when the trial had to be terminated due to ozone-induced structural damage in the treatment chambers. Under the trial conditions, only the Kalanchoe would be able to tolerate the high levels of ozone required to kill the fungal spores.
Influence of Water-soluble and Slow-release Fertilizers on Growth of Pot Carnation in C-Channel Mat Irrigation System
Authors: Pak* Chun Ho , Kang Seung Won , Lee Chiwon W.
Published: February 2019

The influence of water-soluble fertilizer (WSF, 3 different formulations) and slow-release fertilizer (SRF, Osmocote, 14N-6.2P-11.6K) on the growth and quality of potted carnation (Dianthus caryophyllus cv. Invitation) in a C-channel mat irrigation system was investigated. When fertilized with 0.4, 0.8, or 2.0 g·L-1 of WSF (20N-7.9P-16.6K for weeks 1-4, 13K-0.1P-18.8K for weeks 5-11, and 15N-0P-12.5K for weeks 12-15), the 0.8 g·L-1 solution produced the highest quality plants as determined by total shoot fresh and dry weights, leaf area and number, plant height, and number of branches per pot. The quality of plants grown with 0.4 g·L-1 or 2.0 g·L-1 WSF solution was also commercially acceptable. The growth rate of all plants began to accelerate at around 60 days after treatment started, with some variation with the fertilizer treatments. Plants began to show a reduced growth rate at around 90 days from the treatment when they underwent a phase change from vegetative growth to reproductive growth. Plants grown with SRF alone were less vigorous than those grown with WSF, especially when temperature was lower. Results of this study indicate that high quality pot carnations can be produced, using a reduced amount of fertilizer applied to the C-channel mat irrigation system.
Detection of QTL Controlling Fruit Size and Shape in Cucumis melo L.
Authors: Park* Soon O. , Crosby Kevin M.
Published: February 2019

Mature fruit size and shape are important traits of most melon types. Our objective was to identify RAPD markers associated with major QTL affecting fruit weight, length, diameter and shape by means of bulked segregant analysis in an F2 population from the ananas melon cross of Deltex (larger fruit size) × TGR1551 (smaller fruit size). Clear separations for fruit weight, length, diameter, and shape between Deltex and TGR1551 were observed. Continuous distributions for fruit weight, length, diameter and shape were found in the F2 population indicating quantitative inheritance for the fruit traits. Significant positive correlations were detected between fruit weight and shape traits (r = 0.73 to 0.80). A significant positive correlation was observed between fruit weight and glucose (r = 0.35) or fructose (r = 0.25), whereas no correlation was noted between fruit weight and sucrose or total soluble solids. Two small and large bulks for fruit weight and shape were developed from F2 plants. A total of 240 primers were used to simultaneously screen between the small and large bulks, and between Deltex and TGR1551. Twenty-six RAPD markers were polymorphic for the small and large bulks. Ten markers were found to be significantly and consistently associated with fruit size and shape traits on the basis of simple linear regression. Of the 10 markers associated, four displayed an amplified DNA fragment in the small bulk, while six showed an amplified DNA fragment in the large bulk. The associated marker OJ07.350 explained 15% to 27% of the phenotypic variation for the fruit traits. These markers associated with QTL for melon fruit size and shape are expected to be useful in melon breeding programs for modifying fruit size.
Tolerance to Rust (Puccinia allii) in Seed Derived Garlic Progenies
Authors: Jenderek* Maria M. , Hannan Richard
Published: February 2019

In California, rust (Puccinia allii) on garlic (Allium sativum) was not considered an economic problem until 1998, when a severe infection of the disease caused an average 51% reduction in yield throughout the state. The weight of harvested bulbs was 25% to 60% smaller than the average weight in the previous year, and soluble solids were reduced by an average of 15%. Until recently, garlic varieties that are resistant or highly tolerant to rust have not been grown in garlic production fields in California. Open pollinated progenies derived from 3 Plant Introduction accessions of the U.S. Dept. of Agriculture-Agricultural Research Service germplasm collection (PI 493099, PI 540315 and W6 12820) were inoculated with a suspension of urediniospores (1, 2 × 105/mL) isolated from rust infected garlic leaves obtained from production fields in Kings, Fresno and Yolo counties. Inoculations were carried out in a replicated experiment in the field under plastic covers, where 12 hours of misting was applied. The disease symptoms were scored on all leaves of the inoculated plants. The size of observed lesions varied from <1 to 280 mm2. Of the 118 plants evaluated, 9.3% had an average leaf area with rust symptoms of less than 1%. The majority of the plants (83.1%) had 1 to 5% of leaf area infected, and over 6% of plants had symptoms on 5 to 25% of their leaf surface. The highest number of plants with a low percent of rust symptoms on leaves was observed on progenies produced from PI 493099. While all maternal plants used to produce the seeds showed rust symptoms, the presence of progenies with ≤0.5% of leaf area infected indicated that a tolerance source to P. allii may exist in the A. sativum NPGS, germplasm collection.
Nitrogen and Phosphorous Absorption and Leaching from Anthurium Plants Grown in Municipal Solid Waste Compost
Authors: Gonzalez* Lizzette , Vazquez Juan C. , del C. Libran Maria
Published: February 2019

Municipal solid waste compost (MSW) can be used as an effective substrate for ornamental plant production as an alternative to peat. In a previous study a mix with peat, perlite, and vermiculite (1:1:1 per volume) was used along MSW compost at 1:1 per volume ratio as a growing substrate for Catharanthus roseus, providing nitrogen (N) for adequate plant growth. This study will focus in determining if MSW provides adequate amounts of N and Phosphorous (P) for Anthurium pot plant production, reducing the use of fertilizers and nutrient loss to the environment. Plants were fertilized at 0, 100, 150, and 200 ppm N using a 20-10-20 soluble fertilizer. Chemical characterization of leachates collected from plants grown in substrates with or without MSW, to determine possible nutrient run off. Tissue analysis for N and P content was conducted to determine absorption. Our results shows an increase in NH4 -N, NO3 -N and soluble P in leachates as the fertilizer level increased. Higher NO3 -N content in leachates was observed in treatments with MSW. Higher P concentrations were observed in leachates from substrate without MSW. Weeks after, 62% of the plants grown in MSW were dead; the surviving plants had less biomass, but similar N content in leaf and root tissues than plants grown without MSW. Higher P content in tissues was observed in fertilized plants grown without MSW. The MSW was a nutrient source for the plants, but further studies should be conducted for optimum use of MSW as a component of growing substrate.
The Effect of Calcium Sprays and Crop Load on Bitter Pit Incidence in `Honeycrisp' Apple
Authors: Telias* Adriana , Hoover Emily , Rosen Carl , Bedford David
Published: February 2019

`Honeycrisp', a relatively new apple cultivar, is susceptible to bitter pit, a physiological disorder that develops mainly during storage. Although the cause of bitter pit is unknown, calcium (Ca) content of the fruit is known to be involved. A field experiment was conducted in Chanhassen, Minn. to refine recommendations for use of Ca sprays for reduction of bitter pit in `Honeycrisp' apple. Specific objectives were to determine: 1) Ca concentration and content throughout the fruit growing season; and 2) the association of bitter pit incidence with Ca concentration, crop load, vegetative growth and fruit size. Six treatments tested included: control; Ca(NO3)2 sprays all season; Ca(NO3)2 sprays early in the season; Ca(NO3)2 sprays late in the season; hand-thinning combined with Ca(NO3)2 sprays all season and hand-thinning. Ca concentration in fruits was measured bi-weekly using three different sampling methods: segments, cores and plugs. A randomized block design with four trees as experimental unit and five replications was used. Results suggest lower crop loads increase bitter pit incidence. While fruit from the thinned treatments was larger in size by the end of the experiment, no bitter pit was present at harvest. After 4 months of storage, the hand thinning treatment had 7.4% bitter pit, while thinning plus Ca reduced bitter pit to 2.4%. The other treatments had less than 1% bitter pit. Fruit analyses at the end of the growing season indicate that early and full season sprays resulted in the highest Ca concentration in fruit segments and cores. The lowest values were found for the thinning treatment. No association was found between vegetative growth and bitter pit incidence.
Revision Process of Master Gardener Training Curriculum into a More User-friendly Lesson Plan Format
Authors: Kelly* Lelia S.
Published: February 2019

State specialists and agents developed a Master Gardener training curriculum that consisted of a collection of powerpoint presentations in the year 2000. After three years of use this curriculum was in need of revision and updating. The revision process that utilized volunteers, agents, subject matter specialists as well as curriculum specialists will be presented. Suggestions for improvement were gleaned from three years of class evaluations. In addition to obvious updating of material, formatting the curriculum into a lesson plan with complete step-by-step instructions for teachers was required to enable the curriculum to be more easily taught by non-extension personnel such as Master Gardener Educators. Removal of all questionable copyrighted pictures, graphs, drawings, etc. from the original curriculum was accomplished. This process will allow Mississippi State to share this curriculum with other universities if requested without fear of legal repercussions. Aligning the student's training notebook to more accurately reflect the material presented in class was done also. Resource material lists were added and standardized tests for the new material were included. The incorporation of hands-on activities or demonstrations to more actively engage the student in the learning process was included as well. The entire revised training curriculum was contained on a compact disc that was made available to instructors.
Improved Regeneration of Wild Strawberry (Fragaria vesca) Using TDZ and 2,4-D
Authors: Wadl* Phillip A. , Veilleux Richard E.
Published: February 2019

In order to facilitate the high throughput transformation required to use Fragaria vesca (wild strawberry) as a tool in genomic research, functional genomics, and gene discovery not only for strawberry but for fruit crops in general, we need to increase its regeneration frequency and transformation efficiency using Agrobacterium. Ten accessions of F. vesca representing a range of germplasm with worldwide distribution were obtained from the USDA National Germplasm Repository, Corvallis, Ore. for use in shoot regeneration experiments. Seed germination with or without vernalization ranged from 0% to 90%. In vitro growth varied for the accessions with five accessions eliminated from further experiments due to poor growth. In preliminary experiments with 125 leaf explants and 40 petiole explants combined representing PI 551573, PI 602923, and F. vesca `Alpine'; 100% of the uncontaminated explants regenerated at least one shoot after 8 weeks on medium supplemented with 1 mg·L-1 1-phenyl-3-(1,2,3-thiadiazol-5-yl) urea (thidiazuron or TDZ) and 0.2 mg·L-1 2,4-dichlorophenoxyacetic acid (2,4-D). In a replicated study of `Alpine' comparing regeneration on the above TDZ/2,4-D medium with control medium [0.25 mg·L-1 indole-3-butyric acid (IBA)/3 mg·L-1 benzyladenine (BA)], regeneration frequency at 6 weeks for leaf or petiole explants on control medium was 8% (n = 180) compared to 27% (n = 210) on the TDZ/2,4-D medium. This optimized shoot regeneration protocol for F. vesca `Alpine' is currently under investigation in transformation experiments with several other accessions and Agrobacterium constructs.
Mapping QTL for Day-neutrality in Strawberry
Authors: Weebadde* Cholani K. , Hancock James F.
Published: February 2019

While it is important for strawberry breeders to know the genetics of day-neutrality, evidence for inheritance of the trait is still contradictory. It is not known how many genes govern the trait, to what extent each gene affects phenotype and how the environment influences gene expression. Several recent studies point toward a polygenic threshold model and a rejection of the single gene model. A linkage mapping approach is being used to determine if day neutrality can be mapped to several different quantitative trait loci (QTL) that may represent different genes. To confirm that a linkage mapping approach is the method of choice for QTL detection, a small population of the cross `Honeoye' x `Tribute' consisting of 57 progeny segregating for the trait was genotyped with single dose restriction fragment (SDRF) markers and a preliminary genetic map was created using Join Map 3.0. Results separated the molecular markers into at least 24 linkage groups and several putative QTL for day neutrality were identified indicating that the technique will be successful. However, due to the complexity of the octoploid genome of strawberry, over 200 progeny need to be genotyped to build a complete map that includes the 56 linkage groups of the genome. Furthermore, for determining QTL, an accurate phenotypic evaluation is critical. Individuals of the population above were phenotyped under field conditions (East Lansing, Mich.) in 2002 and 2003, and are now being analyzed under controlled temperature and photoperiod conditions for confirmation of the QTL detected for the trait. A larger population of the same cross with over 200 progeny has also been generated and will be mapped using molecular markers after determining their phenotype under the same environmental conditions.
Seed Recalcitrance of Carolina Buckthorn: Implications for Ecology and Horticulture
Authors: Stewart* J. Ryan , Graves William R.
Published: February 2019

Carolina buckthorn (Rhamnus caroliniana Walt.) is ornamental and could be promoted as a stress-resistant shrub for horticultural landscapes. Its status as a relative of invasive species, including common buckthorn (Rhamnus cathartica L.), raises concerns regarding the environmental consequences of planting Carolina buckthorn outside of its natural habitat. To assess the ease of propagating Carolina buckthorn from seed, and to gather data relevant to assessments of invasiveness, we compared seed-germination characteristics between the two species. Seeds of Carolina buckthorn were collected from native populations in Missouri, Oklahoma, and Texas. Seeds of common buckthorn were collected from populations in Iowa. We stratified seeds of both species for up to 112 days at 4 °C. Germination at 20 °C then was evaluated for 56 days. Over stratification durations, 40% and 71% of seeds of Carolina buckthorn and common buckthorn germinated, respectively. Stratification for 112 days optimized germination value for Carolina buckthorn, but stratification for 42, 56, 84, and 112 days evoked similar germination percentages. Seeds of Carolina buckthorn from Oklahoma germinated at a higher percentage (56%) than did seeds from Missouri (25%). Neither germination value nor germination percentage of common buckthorn was influenced by stratification. We conclude that seeds of Carolina buckthorn are more recalcitrant than are seeds of common buckthorn. This suggests that Carolina buckthorn, particularly those from Missouri with low reproductive success, may be less invasive than their Eurasian kin. Horticulturists can optimize germination percentage of Carolina buckthorn by cold-stratifying seeds for as little as 42 days, but 112 days optimizes germination value.
Biostimulants Improve Post-winter Performance of Residential St. Augustinegrass
Authors: Morales-Payan* J. Pablo , Stall William M.
Published: February 2019

A glycine-rich mixture of amino acids and short-chain peptides (Siapton) (3 g a.i. per L), two citokinin-rich seaweed (Ascophyllum nodosum) extracts (Stimplex and Triggrr) [50 mg·L-1, active ingredient (a.i.)], a mixture of cysteine and folic acid (Ergostim) (300 mg·L-1 a.i.), and a terpenic acid-rich Siberian fir (Abies sibirica) extract (Silk) (50 mg·L-1 a.i.) were sprayed on St. Augustinegrass residential turf at the beginning of the post-winter regrowth in Gainesville, North-Central Florida, to determine their effect on the growth and aesthetics of the lawn. Above- and belowground biomass, leaf color, and density in St. Augustinegrass were enhanced by all the biostimulants, as compared to untreated St. Augustinegrass plots. The best results were obtained, in descending order, with the cytokinin-rich seaweed extracts, the glycine-rich mixture of amino acids and short-chain peptides, the mixture of cysteine and folic acid, and the terpenic acid-rich Siberian fir extract.
The Response of Four Anthurium (Anthurium andraeanum) Cultivars to Five Sequential Applications of Four Preemergence Herbicides
Authors: DeFrank* Joe , Leary James J.K.
Published: February 2019

An experiment to determine the response of four potted anthurium cultivars to sequential preemergence herbicide applications was conducted at a commercial nursery located in Mt. View on the Island of Hawaii. The four cultivars tested were: Lady Ann, Sundial, Tropic Fire, and Nicoya. Herbicides were applied at two rates, the anticipated labeled use rate (1X) and two times the anticipated labeled use rate (2X). The herbicides evaluated in this experiment were diuron, isoxaben, sulfentrazone and oryzalin. Herbicide applications were directed to the base of plants to avoid direct contact with leaves and flowers. Applications were made at 64-, 69-, 70-, and 98-day intervals for a total of 5 sprays. At 71 days after the last spray application, each plant was collected to determine the number of flowers and dry weight accumulation of leaves, shoots and roots. There was a significant interaction between the chemical treatments and the cultivar for leaf dry weight accumulation. Sulfentrazone 1X and 2X significantly reduced the dry weight in all four cultivars compared to the untreated controls. Leaf weights for the isoxaben (1X) treatments were not significantly reduced for all cultivars. However, `Lady Anne' was significantly reduced at the 2X rate of isoxaben. Leaf weights for diuron and oryzalin at both 1X and 2X treatments were not significantly different from the untreated control. Only sulfentrazone reduced shoot dry weight and flower number. Diuron was the only herbicide that did not reduced root dry weight.
Effects of Grape Berry Developmental Stages on Ammonium Nitrate-enhanced Penetration of Gibberellin A3
Authors: Ohara* Hitoshi , Ungsa Marom , Ohkawa Katsuya , Matsui Hiroyuki , Bukovac Martin J.
Published: February 2019

The effects of ammonium nitrate (AMN) on the penetration of Gibberellin A3 (GA3) into berries of `Kyoho' (Vitis labruscana Bailey) grape during berry development were studied. Treatment solutions of GA3 (100 ng·μL-1) and GA3 + AMN (20 millimolar concentration) were applied to the surface of grape berries under field conditions. The amount of GA3 penetrated was assayed using dwarf rice (Oryza sativa L., cv. Tan-ginbozu). At full bloom, the addition of AMN significantly enhanced GA3 penetration 24, 48 ad 72 hours after application by 13%, 16% and 21% of the applied GA3, respectively, representing a 1.7- to 2.4-fold increase over GA3 alone. At 4 weeks after full bloom (WAFB) at 24 hours after application, 20% of the applied GA3 penetrated in the presence of AMN compared to 15% in the absence of AMN. From varaison (7 WAFB) to maturity (10 WAFB), GA3 penetration decreased, from 6% to 2%, respectively, in the presence of AMN, and from 3% to 1% in the absence of AMN. The addition of AMN to the GA3 solution increased GA3 penetration relative to GA3 alone at all berry developmental stages. On the other hand, Cuticular wax density on the berry surface at 4 WAFB was 1.10 μg·mm-2, 5.8-fold greater than at full bloom (0.19 μg·mm-2). The thickness of the epidermal tissue doubled during the first 2 WAFB, but was maintained almost constant over the next 6 weeks. GA3 penetration was more closely related to the cuticular wax levels than the epidermal tissue thickness.
Studies on the Nitrogen Absorption Rule
Authors: Xu* Kun , Wang Xiufeng , Wang Fang
Published: February 2019

The rate of fertilizer-N utilization by ginger was quite different in different applying stages. The results indicated that the rate of fertilizer-N utilization increased with the delay of application. The highest utilization rate was the fertilizer dressed at middle period of vigorous growth, which was 45.24%; while the basal manure utilization rate was only 27.67%. It was also shown that the nitrogen uptake from basal manure was distributed in highest level in main shoots and leaves, the nitrogen derived from fertilizer dressed at middle period of vigorous growth was mostly distributed into rhizomes, and nitrogen absorbed from fertilizer dressed at early period of vigorous growth was distributed evenly into all organs. The reclamation rate from fertilizer dressed at middle period of growth was the highest and lowest reclamation rate was the basal manure. The content of fertilizer-N and soil-N in ginger plant was determined, it was shown 56.57% plant-N was derived from soil-N, the remaining 43.43% was from fertilizer-N. The nitrogen from soil played a very important role in ginger production, therefore the problem of how to maintain high soil fertilizer must be paid more attention.
Utilizing Aboveground Rhizotrons to Study Root Growth and Pathogen Movement in Simulated Orchard Conditions
Authors: Watson* Wesley T. , Appel David N. , Arnold Michael A. , Kenerley Charles M. , Starr James L.
Published: February 2019

Several techniques have been used to study root growth and pathogen movement along roots between trees, including profile walls, micro-rhizotrons, and soil cores. These assessments can be very time consuming, cost prohibitive, and ineffective when studying soilborne pathogen movement across overlapping roots between adjacent trees in an orchard. Three aboveground rhizotrons were designed and constructed to study the movement of Phymatotrichopsis omnivora (Duggar) Hennebert (syn. Phymatotrichum omnivorum Duggar) along overlapping apple roots [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf. (syn. M. domestica Borkh. non Poir.)] in simulated orchard conditions. Two experiments involved boxes using either observation windows or micro-rhizotron observation tubes between trees. A third experiment utilized 45-gallon containers (171,457 cm3) joined by innovative observation windows. The container rhizotrons reduced labor and material costs, were more effective at monitoring roots, were more convenient than field measurements, and more closely simulated orchard growing conditions. This method provides several advantages to better study and manipulate the rooting environment of orchard-grown trees.
Early Performance of `Fuji' Apple Trees on Several Dwarf Rootstocks in the 1999 NC-140 Rootstock Trial
Authors: Autio* Wesley , Anderson LaMar , Barritt Bruce , Crass-weller Robert , Ferree David , Greene George , Johnson Scott , Masabni Joseph , Parker Michael , Reighard Gregory
Published: February 2019

`Fuji' apple trees [Malus ×sylvestris (L.) Mill. Var domestica (Borkh.)] on nine dwarfing rootstocks (CG.4013, CG.5179, G.16N, G.16T, M.9 NAKBT337, M.26 EMLA, Supporter 1, Supporter 2, and Supporter 3) were planted at 10 locations (CA, KY MO NC OH 2 in PA SC UT and WA) under the direction of the NC-140 Multistate Research Project. After four growing seasons (through 2002), largest trees were on CG.4013. Smallest trees were on M.9 NAKBT337, Supporter 1, Supporter 2, and Supporter 3. Trees on CG.5179, G.16 N, G.16T, and M.26 EMLA were intermediate. Cumulative root suckering was greatest from trees on CG.4013 and similar from the other rootstocks. CG.4013, CG.5179, and G.16T resulted in the greatest yields per tree in 2002, and M.26 EMLA, M.9 NAKBT337, Supporter 2, and Supporter 1 resulted in the lowest. Cumulatively, CG.4013 resulted in the greatest yields per tree, and M.26 EMLA resulted in the lowest. Rootstock did not affect yield efficiency in 2002, but cumulatively, Supporter 1, Supporter 2, and Supporter 3 resulted in the most efficient trees, and M.26 EMLA the least. Fruit weight in 2002 or on average was not affected by rootstock. Limited data will be presented on CG.3041, CG.5202, and CG.5935, which are planted only at some locations. Data for the fifth season (2003) will be presented.
Early Performance of `McIntosh' Apple Trees on Several Dwarf Rootstocks in the 1999 NC-140 Rootstock Trial
Authors: Autio* Wesley , Cline John , Crassweller Robert , Embree Charles , Garcia Elena , Hoover Emily , Kosola Kevin , Perry Ronald , Robinson Terence
Published: February 2019

`McIntosh' apple trees [Malus ×sylvestris (L.) Mill. Var domestica (Borkh.)] on 10 dwarfing rootstocks (CG.3041, CG.4013, CG.5179, CG.5202, G.16N, G.16T, M.9 NAKBT337, Supporter 1, Supporter 2, and Supporter 3) were planted at 10 locations (MA, MI MN NS 2 in NY ON PA VT and WI) under the direction of the NC-140 Multistate Research Project. After four growing seasons (through 2002), trees on CG.5202 and CG.4013 were significantly larger than those on all other rootstocks. Smallest trees were on M.9 NAKBT337. Trees on other rootstocks were intermediate. Rootstock did not influence cumulative root suckering. Yield per tree in 2002 was greatest from trees on CG.4013 and lowest from trees on M.9 NAKBT337; however, cumulatively, trees on M.9 NAKBT337 and CG.4013 yielded the most. Yield efficiency in 2002 was not affected by rootstock. Cumulatively, rootstock had very little effect, but trees on CG.5202 were the least efficient. In 2002, M.9 NAKBT337, CG.3041, and Supporter 2 resulted in the largest fruit, and CG.5179 resulted in the smallest. On average, M.9 NAKBT337 resulted in the largest fruit, and G.16T resulted in the smallest. Limited data will be presented on CG.5935 and M.26 EMLA, which are planted only at some locations. Data for the fifth season (2003) will be presented.
Carotenoids and Quality of Watermelon as Affected by Deficit Irrigation and Growing Season
Authors: Bang* Haejeen , Leskovar Daniel I. , Yoo Kilsun
Published: February 2019

This experiment was conducted to determine the effects of deficit irrigation and growing season on fruit quality, carotenoid content and yield of red-, orange-, and yellow-fleshed diploid and triploid watermelon. Irrigation rates were 1.0 evapotranspiration (ET) and 0.5 ET. Diploid cultivars were Summer Flavor 710 (red), Tendersweet (orange), and Summer Gold (yellow). Triploid cultivars were Summer Sweet 5244 (red), Sunshine (orange), and Amarillo (yellow). Four-week old containerized transplants were planted in the field at TAES-Uvalde on 27 Mar. and 21 May 2003. Deficit irrigation imposed after plants were fully established reduced the individual fruit weight and size in the early planting. Soluble solids content (SSC) and firmness was not affected by irrigation rate in both plantings. SSC varied across cultivars and increased with maturity, particularly for the triploid cultivar Amarillo. In general, triploids were firmer than diploid cultivars. Total carotenoid content was not affected by irrigation during early planting. Diploid and triploid red-fleshed watermelon cultivars had significantly higher carotenoid content than orange- and yellow-fleshed cultivars. The major carotenoid was lycopene (more than 65%), followed by prolycopene (20%) and B-carotene (7%).
Qualitative and Quantitative Measures of Onion Bulb Firmness
Authors: Larsen* Troy A. , Cramer Christopher S.
Published: February 2019

Current onion varieties that are grown in New Mexico were developed for hand harvesting and not for mechanical harvesting. In order for onion production in New Mexico to remain a viable commodity, firmer onion varieties need to be developed for mechanical harvesting. In this study, bulb firmness of onions was examined in short and intermediate-day onion entries comparing a qualitative `finger pressure' method with a digital FFF-series durometer. After harvesting and curing of the onion bulbs, dry outer scales were removed before durometer measurements were taken at two perpendicular points on the vertical center axis of the bulb. Following the durometer measurements, bulb firmness was rated by `finger pressure' applied to multiple points on the vertical center axis. For intermediate and late-maturing entries, durometer measurements and firmness rating were positively correlated in a strong fashion (r = 0.77 to 0.87). Early maturing entries, NMSU 02-25 and NMSU 02-03 both had high durometer averages and firmness ratings. `NuMex Crimson' and `NuMex Crispy' had the highest durometer averages and firmness ratings among intermediate maturing entries while `NuMex Solano' and NMSU 01-06 had the highest among late maturing entries. From our results, the durometer can be useful in providing a quantifiable measure of bulb firmness.
Supercritical Fluid Extraction of Limonoids from Grapefruit Seeds
Authors: Yu* Jun , Toledo Romeo , Singh Rakesh , Pike Leonard , Patil Bhimanagouda
Published: February 2019

Grapefruit seeds were studied for the extraction of limonoids using supercritical CO2 extraction (SC-CO2) technique. Limonin aglycone was successfully extracted with SC-CO2 directly from grapefruit seeds; and the limonin glycoside was extracted using SC-CO2 and ethanol as co-solvent from the spent seeds after the extraction of limonin aglycone. In an effort to optimize the extraction conditions of limonin aglycone, pressure, temperature, time effects were investigated. Various times of extraction, CO2 flow rate and the feeding modes of CO2 were also employed to obtain the highest yield of limonin aglycone. Optimal conditions to achieve the highest limonin aglycone (0.63 mg/g seeds) were 48.3 MPa, 50°C and 60 min with CO2 bottom feeding, flow rate about 5 L/min. The extraction conditions for limonin glycoside to achieve highest yield were further optimized. The highest extraction yield (0.62 mg limonin glycoside/g seeds) were at 48.3 MPa, 50°C, 30% molar fraction of ethanol (XEth =0.30) and 40 min with CO2 top feeding, flow rate about 5 L/min. The results demonstrated that supercritical CO2 extraction of limonoids from grapefruit seeds, a citrus juice industry byproduct, has practical significance for commercial production.
Glycoalkaloid and Chlorophyll Changes in Eight Potato Varieties Exposed to Light
Authors: Dickie Francine , Voss* Ron , Hong Gyunghoon , Cantwell Marita
Published: February 2019

Red and white skin potatoes (`Cal Red', `Cal White', `Durango', VC1015, `Yukon Gold', `Latona', A94381, and `Satina') were harvested from plots in commercial fields in Kern and San Joaquin Counties and at the Univ. California Research Center at Tulelake. After washing and sorting, potatoes were held in plastic trays in the dark (black plastic bags) or exposed to light (90 cm below cool-white fluorescent GE Watt-Miser 34W bulbs, ≈1300 lux) at 20 °C. After 0, 3, 6 and 9 days, potatoes were scored for appearance of greening (1 to 5 scale), evaluated for external color (L*a*b* color values), skin chlorophyll concentration, and glycoalkaloid concentrations. For the latter, freeze-dried slices of tuber were extracted and analyzed by colorimetry and HPLC for alpha-solanine and alpha-chaconine. Initial glycoalkaloid concentrations varied among cultivars, with `Cal Red' consistently having the highest concentrations. Tubers stored in the dark had no or a slight increase in glycoalkaloid concentrations. Light exposure resulted in increased glycoalkaloid concentrations in all cultivars, but to varying degrees. Some varieties had negligible changes while others increased as much as eightfold. The average increase was 300%. Generally, `Cal White' had the largest light-induced increases in glycoalkaloids.
The Inheritance of Several Traits in Three Diploid Interspecific Rose Populations
Authors: Shupert* David , Anderson Natalie , Byrne David
Published: February 2019

Seedlings from three interspecific backcross rose populations derived from a F1 population were used to study inheritance of several traits in roses. Three F1 plants (WOB13, WOB21, and WOB26) from the hybridization of the diploid parents Rosa wichuraiana and `Old Blush' were backcrossed to `Old Blush' to produced three populations to observe the segregation of several morphological and disease resistance traits. The segregating rose traits in the backcrosses are no prickles on stems, non-recurrent blooming habit, white single flowers, black spot resistance, and powdery mildew resistance present in the Rosa wichuraiana parent compared to prickles on stems, recurrent blooming habit, pink double flowers, black spot susceptible, and powdery mildew susceptible present in the `Old Blush' parent. Visual data was collected for the segregating traits using color standards and rating scales as appropriate. The three populations expressed the segregating traits to varying degrees. Under the environmental conditions at College Station, Texas the population `Old Blush' × WOB26 had a greater expression of the traits for no prickles on stems, recurrent blooming habit, disease resistance to black spot, and disease resistance to powdery mildew, which are traits desired in breeding programs. The segregation of flower color (white/pink), and flower type (single, semi double, and double) were similar in all three populations.