bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and Fertilizer Consumption of Single-node Cutting Rose `Versillia' by Mineral Nutrient Control in a Closed Hydroponic System
Authors: Yang* Eun Young , Park Keum Soon , Lee Dong Soo , Lee Yong-Beom
Published: February 2019

This study was conducted to understand the effect of different nutrient control method on the growth, cut-flower quality, root activity and fertilizer consumption. 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, 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). The mineral nutrient control method had significantly effected on the cut-flower quality. In the M&M and M, flower length, fresh weight and root activity were higher than those with other mineral nutrients control method. Although EC-A and EC-D could save total amount of fertilizer compared to M&M and M, the growth and quality of the rose with EC control system were lower than those with mineral nutrient control system. Therefore, these result suggest that EC control system is not economic method in a closed hydroponic system.
Fertility Affects Susceptibility of Chrysanthemum to Western Flower Thrips: Influence on Plant Growth, Photosynthesis, and Ethylene Evolution
Authors: Davies* Fred , He Chuanjiu , Chau Amanda , Heinz Kevin , Spiers Jay
Published: February 2019

This research details the influence of fertility on plant growth, photosynthesis and ethylene evolution of chrysanthemum (Dendranthema grandiflora Tzvelev var. Charm) inoculated with western flower thrips (Frankliniella occidentalis (Pergande). We tested the hypothesis that moderate levels of nitrogen would better control western flower thrips on chrysanthemum. While thrips are known to reduce plant quality, there have been few comprehensive studies on plant response to thrips population dynamics—analyzing changes in plant growth and development, plant gas exchange and ethylene evolution. Plants were exposed to four fertility levels that consisted of 0%, 10%, 20% and 100% (375 ppm N) of recommended nitrogen levels. Thrips abundance was greatest at high fertility. Thrips depressed plant vegetative and reproductive growth and altered carbohydrate partitioning. Thrips-inoculated (TI) plants also had reduced leaf area and lower leaf mass than thrips-free (NonTI) plants, but did not differ in specific leaf area [(SLA) leaf area (cm2)/leaf DM (g)]. However, high fertility plants had greater biomass and higher SLA, i.e., thinner leaves than low fertility treatments. Thrips reduced photosynthesis (Pn) and stomatal conductance (gs) in young, mature and older basal leaves, with gs showing greater sensitivity than Pn. Ethylene and chlorophyll levels in thrips damaged leaves did not differ from Non-TI plants.
Off-season Strawberry Production under High Tunnel Compared to Open Field in Kansas
Authors: Kadir* Sorkel , Carey Edward
Published: February 2019

High tunnel strawberry (Fragaria × ananassa) production experiment was conducted in south central Kansas, which consisted of two cultivars and four tunnels. The same experimental design was conducted under field conditions. The objectives of this study were to compare strawberry production and quality under high tunnels to those grown in the field and to assess the potential for high tunnels for early-season strawberry production. Plug plants of `Sweet Charlie' and `Chandler' were planted October 18. Plants were spaced at 12” × 12 “in double rows on raised beds covered with black plastic mulch. Protected plants under high tunnels had 100% winter survival rate compared to 60% of the field plants. Yield and berry quality of the high tunnel plants were by far better than those of field grown plants. Plant growth under high tunnels was about three to four fold higher than the unprotected field plants. `Sweet Charlie' flowered in early February and produced berries one week earlier than `Chandler'. Both cultivars were harvest from early April through late May at weekly interval. `Sweet Charlie' in early April produced an average berry weight of 14 g, soluble solids of 8 °Brix, and the largest average berry weight was 15 g. `Chandler' harvested late April produced larger berries than `Sweet Charlie' with the largest average berry weight of 35 g compared to 31 g for `Sweet Charlie'. In mid May, `Chandler' produced 72% higher yield than `Sweet Charlie'. High tunnel not only produced higher yield and better quality berries than field strawberries but it has a potential to produce early crop and extend the season production of strawberry in Kansas.
Photosynthesis and Rubber Production in Transgenic Guayule (Parthenium argentatum, Gray) in Response to Cold Night Temperatures
Authors: Veatch* Maren E. , Ray Dennis T.
Published: February 2019

Rubber production in guayule (Parthenium argentatum, Gray) is highest in the winter months. It has been suggested that lower nighttime temperatures stimulate rubber production. Higher rubber production could be the result of up regulation of the enzymes involved in rubber synthesis, or acclimation of the photosynthetic apparatus to cold temperatures, making photosynthates available for rubber production when the plants are not actively growing, or a combination of the two factors. The effect of low night temperatures on photosynthesis and rubber production was examined in greenhouse grown plants. The experiment was set up as a split plot with different sub plots enclosed in heated or non-heated containers during the night. Those placed in non-heated containers were exposed to the ambient night temperatures of the greenhouse. During the growing season, growth was measured as change in height, and midday and diurnal photosynthetic measurements were collected. At harvest fresh and dry weight of both roots and shoots were taken. Resin and rubber were then extracted with acetone and cyclohexane respectively. Midday photosynthesis was as high or higher in cold night plants than in the warm night plants. In addition, the cold night treatment had lower growth than the warm night treatment. Percent resin and rubber were significantly higher in both shoots and roots of cold night plants, as was the overall yield of rubber. An increase in photosynthetic rate in the cold night treatment, without the concomitant increase in growth seen in the warm night treatment, could account for the increase in rubber production during the winter months.
Application of Reflectance Spectroscopy in `Fuji' Apple Sunburn Early Detection
Authors: Ding* Pinghai , Fuchigami Leslie H.
Published: February 2019

Sunburn can be caused either by heat stress or by UV-B radiation. Under natural conditions fruit sunburn is usually caused by the combination of both heat stress and UV-B radiation. To evaluate the use of reflectance spectroscopy in early detection of fruit sunburn, 5-year-old `Fuji' apple bearing trees growing in pot-in-pot system at the Lewis-Brown Horticulture Farm of Oregon State Univ. were used in the experiment. Fruit sunburn was monitored either under natural conditions or treated with UV-B, heat or both under controlled conditions after detached from the tree. Under natural conditions, the sun-exposed side of Fuji fruit has much higher anthocyanins than the shaded side. The increase in anthocyanins at the sun-exposed side is to protect the fruit from sunburn. When the temperature higher than 40 °C the sunburn symptom initiated first by change the color of the sun-exposed side from red to tan, then to yellow patches, and finally turn to brown and dark brown patches. The peel pigments analysis results indicated that anthocyanins decreased earlier than chlorophyll in the symptom development. The results of detached fruit exposure to 30,000μW/cm2 UV-B lights or to 40 °C at control conditions for 2, 4, 6, 8, 10, and 12 hours indicated that high intensity UV-B lights or high temperature alone can cause sunburn respectively. The UV-B and temperature combination treatment enhanced the sunburn processes. The apples with sunburn caused under natural conditions or under UV-B and temperature controlled conditions were scanned by using reflectance spectroscopy of FOSS NIR system at different stage of the sunburn. The results indicted that Fuji apple sunburn can be efficiently detected at the early stage of sunburn in both natural and controlled conditions.
The Identity of the African Firebush (Hamelia) in the Ornamental Nursery Trade
Authors: Pooler* Margaret R. , Elias Thomas S.
Published: February 2019

The neotropical shrub Hamelia patens Jacq. has been cultivated as an ornamental in the United States, Great Britain, and South Africa for many years, although only in limited numbers and as a minor element in the trade. In recent years, other taxa of Hamelia have been grown and evaluated as new flowering shrubs. The relatively recent introduction of a superior ornamental species of Hamelia called the “African firebush” has propelled this genus to greater prominence as an excellent small flowering shrub or container plant, especially throughout the southeastern United States and in other countries such as South Africa. Initially, this firebush was sold as an African plant. Data from field studies, herbarium specimens, and from DNA analysis of several taxa and populations of Hamelia show that the African firebush in southern Florida may have originated from populations of Hamelia patens var. glabra native to southern Mexico. The original plants were taken to Europe, southern Africa, and southeastern Asia probably in the mid to late 1800s and then recently re-introduced to New World markets as a new African ornamental plant.
Latest Developments in Crapemyrtle Breeding at the U.S. National Arboretum
Authors: Pooler* Margaret R.
Published: February 2019

The crapemyrtle (Lagerstroemia) is one of the most widely planted and beloved woody ornamental landscape plant in the Southern United States. With hundreds of named cultivars that offer the grower and gardener diverse combinations of flower color, growth habit, and bark characteristics, crapemyrtles are planted primarily for their spectacular bloom in mid to late summer. The crapemyrtle breeding program at the U.S. National Arboretum was started in the early 1960s, and has resulted in the release of 31 improved cultivars of L. indica, L. indica × L. fauriei, and most recently, hybrids between L. indica, L. fauriei, and L. limii. The development of these cultivars, with a focus on the newly released red-flowering cultivars `Arapaho' and `Cheyenne', will be the focus of this poster. Information on Lagerstroemia germplasm, historical perspective, and breeding methodology and goals will be presented.
Evaluation of Caladium Cultivars for Resistance to Pythium Root Rot
Authors: Deng* Zhanao , Harbaugh Brent K. , Kelly Rick , Seijo Teresa , McGovern Robert J.
Published: February 2019

Caladiums (Caladium × hortulanum) are widely grown for their bright colorful leaves. Pythium root rot, caused primarily by P. myriotylum, is one of the most important diseases in caladiums. This disease can dramatically reduce plant growth, impact plant aesthetical value, and lower tuber yield. Pythium infection in the roots may also lead to subsequent entry of Fusarium into tubers resulting in tuber rot. There has been a strong interest in the tuber production and greenhouse plant production industries to identify cultivars that are resistant or tolerant to Pythium. However, few studies have been conducted since the pathogen was identified, and little information is available regarding the existence of any possible resistance in commercial cultivars. Pythium isolates were made from diseased plants collected from different sites; their pathogenicity was confirmed using tissue culture-derived plants. Procedures were developed for oogonia spore production, inoculation, and disease severity assessment. Nineteen major commercial cultivars were inoculated at two spore densities and then maintained in greenhouses under growing conditions favorable for root rotting. Plant appearance, leaf characteristics and severity of root rotting were evaluated 2-3 times after inoculation. Observations indicated that the isolates were highly virulent. They induced visible root rot within 3-5 days, and caused a complete loss of the root system and plant death for some cultivars within 2-3 weeks after inoculation. Several cultivars, including `Candidum' and `Frieda Hemple' which are widely grown cultivars, had much less root rot, higher plant survival, and seemed to have moderate levels of resistance.
Comparison of Morphological and Genetic Characteristics of 15 Sweetpotato [Ipomoea batatas (L.) Lam] Accessions Grown on Guam
Authors: Pama* Rozalyn , Doronila Jay , Marutani Mari
Published: February 2019

Fifteen sweetpotato [Ipomoea batatas (L.) Lam] accessions grown on Guam were studied for morphological and genetic characteristics. Accessions, obtained from AVRDC (Asian Vegetable Research and Development Center) in Taiwan, Saipan, Rota, and Guam, were investigated for marketable yield, growth habit and characteristics of tuberous roots (color, shape, sugar content and moisture content). Results of this study were used to determine the morphological relationship of the accessions of sweetpotato. Phenetic analysis revealed four major clusters according to tuberous root characteristics. The genetic relationship of these sweetpotato accessions was also evaluated for genetic differences among accessions. DNA was extracted and went through polymerase chain reaction (PCR). PCR products were analyzed by random amplified polymorphic DNA (RAPD) fingerprinting. Result of the genetic relationship among the sweetpotatoes was compared with the morphology of accessions using UPGMA cluster analysis and principal compounds analysis.
Identification of QTL Affecting Sugars in Ananas Melon
Authors: Park* Soon O. , Crosby Kevin M. , Sinclair Jonathan W. , Yoo Kilsun , Pike Leonard M.
Published: February 2019

Sucrose, fructose, total sugars and soluble solids are major factors in determining mature melon fruit sweetness. Bulked segregant analysis was utilized to detect RAPD markers associated with QTL for sucrose, total sugars and soluble solids in an F2 population from the ananas melon cross of Deltex (high sugars) × TGR1551 (low sugars). Sucrose, glucose, fructose and total sugar data were obtained from 108 F2 plants by means of HPLC. Clear separations for sucrose, total sugars and soluble solids between Deltex and TGR1551 were observed, whereas slight differences for glucose and fructose were found. Continuous distributions for sucrose, total sugars and soluble solids were observed in the F2 population indicating quantitative inheritance for the sweetness traits. A significant negative correlation was observed between sucrose and glucose (r = -25) or fructose (r = -0.31). A significant positive correlation was noted between sucrose and total sugars (r = 0.80) or soluble solids (r = 0.64). Three low and high DNA bulk pairs for sucrose, total sugars and soluble solids were developed. A total of 360 primers were used to simultaneously screen between the low and high bulks, and between Deltex and TGR1551. Sixty-eight RAPD markers were polymorphic for the low and high bulks. Of the 68 markers, 24 were found to be significantly associated with sucrose, total sugars or soluble solids on the basis of single-factor ANOVA. Marker OM15.550 was consistently associated with QTL affecting sucrose, glucose, fructose, total sugars and soluble solids, and accounted for 7% to 25% of the phenotypic variation for the traits. These markers associated with the sugar synthesis QTL could be useful to transfer these genes into a low sugar cultivar to enhance the fruit sweetness.
Effects of Fertigation with Nitrogen on Growth and Cropping of `Elstar' Apple Trees
Authors: Cmelik* Zlatko , Tojnko Stanislav
Published: February 2019

The trial was conducted in a `Elstar'/M9 orchard (2500 trees/ha) and the experiment was designed as a split-block comprising five treatments (fertigation with 45 kg·ha-1 N, 60 kg·ha-1 N, 120 kg·ha-1 N, irrigation without fertilizers, and control—without irrigation and without fertilizers), and two timing variants (treatments during vegetation period from 1 May to 20 June—variant A, and treatments from 1 May to 1 Aug.—variant B). The treatments were imposed beginning in the second year after planting and lasted five years. Fertigation with different amounts of nitrogen had no consistent effect on tree growth, cumulative yield and yield efficiency, however, treatments had a significant influence on regularity of bearing. The index of alternate bearing varied with treatment, but in both variant was significantly higher in control and in treatment with irrigation without application of fertilizer. These results demonstrated that the natural tendency of `Elstar' to alternate bearing could be broken by the different rates of nitrogen applied by fertigation.
Determination of Optimal Nitrogen Requirements for Ratibida columnifera Biomass Production and Flowering
Authors: Kincaid* Rebecca , Dougher Tracy
Published: February 2019

There has been an increasing interest in drought tolerant native flower species for Montana residential landscapes and roadsides. Ratibida columnifera is a drought tolerant, perennial wildflower that can be used in home gardens as well as on roadsides. However, there is no knowledge of how R. columnifera will respond to typical nitrogen fertilization in residential landscapes. Our objective was to determine the correct nitrogen application required for R. columnifera to acquire optimal growth and development. After germinating and transplanting R. columnifera seedlings, nitrogen treatments began with five groups containing six pots in each group. Pots were fertilized with 100 ml of ammonium nitrate at 0ppm N, 25 ppm N, 50 ppm N, 75 ppm N, or 100 ppm N at weekly intervals. All pots were fertilized with 100 mL of 50 ppm potassium phosphate. Three plants from each treatment were harvested 30 days after the start of fertilization treatments and underwent biomass evaluations of their fresh and dry weights. The remaining three pots from each treatment were evaluated at blooming for time to flowering, flower number, and flower quality. R. columnifera biomass at 30 days benefited from 25-50 ppm nitrogen, but did not increase biomass above 50 ppm. Flowering was affected at different levels than biomass and was delayed by high nitrogen.
Nitrogen Source and Concentration Affect Growth and Performance of Bedding-plant Impatiens
Authors: Romero* Fredy R. , Gladon Richard J. , Taber Henry G.
Published: February 2019

Impatiens (Impatiens wallerana Hook. f.) is the most important annual bedding plant in the US, based on wholesale dollar volume. Production of high-quality plants requires optimization of the nutrition regimen during growth, especially the total nitrogen (N) concentration and the ratio of N sources. Our objective was to determine the N concentration and ratio of N sources that optimize bedding-plant impatiens growth and development. We used four N concentrations (3.5, 7, 10.5, and 14 mmol·L-1 of N) in factorial combination with four ratios of nitrate-N (NO3--N) to ammonium-N (NH4+-N) (4:0, 3:1, 1:1, and 1:3). Application of treatments began at day 30, and every-other-day applications were conducted until day 60. From day 60 to day 70 only deionized water was applied. N concentration and source displayed interation for most growth parameters. When N was supplied at a concentration ≤7 mmol·L-1, the NO3--N to NH4+-N ratio did not affect growth. When N was supplied at a concentration ≥10.5 mmol·L-1, a 1:3 NO3--N to NH4+-N ratio yielded the greatest shoot dry weight, shoot fresh weight, plant diameter, and number of flower buds per plant. With a NO3--N to NH4+-N ratio of 4:0, these growth parameters decreased. To produce high-quality, bedding-plant impatiens, N should be applied at NO3--N to NH4+-N ratios between 1:1 and 1:3 in combination with an N concentration of 10.5 mmol·L<-1 at each fertigation from day 30 to day 60 of the production cycle.
Antimicrobial Effect of Guava Products against Foodborne Pathogens
Authors: Yang* Guochen , Ibrahim Salam A. , Niedziela Carl E.
Published: February 2019

This study investigated antimicrobial effects of guava products on the survival and growth of Escherichia coli O157:H7 in liquid medium. Seven strains of E. coli O157:H7 (944, 380, E0019, F4546, H1730, Cider, 9727) were tested. These strains were maintained in BHI broth. Guava fruits were sliced into small pieces and blended using a blender. Guava juice and leaves were then extracted using three solvents: water, methanol and hexane. Fruit extracts were dissolved in 10 ml BHI broth tubes to make a fruit solution of 5% (w/v). E. coli O157:H7 was inoculated into fruit solutions at 2 log cfu/mL. After incubation at 37 °C for 24 h, samples were serially diluted 10 folds. The proper diluent was spread-plated on TSA in duplicate. After incubation at 35 °C for 24 h, viable cell counts were obtained. The experiment was replicated three times in a randomized complete-block design. Results demonstrated that guava products (fruit, juice, and leaf extracts) significantly reduced survival and growth of the tested foodborne pathogen strains. Water extract showed the highest antimicrobial activity, followed by methanol and hexane. These results indicate guava extracts are a potential antimicrobial agent to ensure food safety.
Influence of Physical Parameters on the Growth, Morphogenesis and Volatile Monoterpene Production in Mentha spicata L. Cultures In Vitro
Authors: Tisseret* Brent , Vaughn Steven
Published: February 2019

The influence of altering the physical environment on the growth (fresh weight), morphogenesis (leaf, root, and shoot numbers) and secondary metabolism (i.e., volatile monoterpene, and carvone) of Mentha spicata L. (spearmint) shoots cultured on MS medium was studied. The type of physical support (e.g., agar, liquid, platforms, or glass supports) using Magenta vessels altered growth and morphogenesis. Mint shoots grown on liquid produced 4-x fold more fresh weight than on agar. Carvone levels were unaffected physical supports. Increasing the frequency of media replacement significantly increased growth without altering carvone. Vessel size influence was tested by culturing shoots on culture tubes, Magenta vessels and ½-gal. jars. Positive correlations occurred between vessel capacity and culture growth, morphogenesis and carvone levels. A comparative study testing several spearmint cultivars on either culture tubes or an automated plant culture system (APCS, a sterile hydroponics system) was conducted. The APCS produced more biomass (e.g., ≈15-x fold increase in fresh weight), morphogenesis and carvone than employing culture tubes. Carvone was only produced from shoots and was absent in either roots or callus. Carvone levels decreased proportionally in shoots as the distance from the shoot terminus increased. Altering the number of media culture immersions (4, 8, 12, or 16 immersions/day) with the APCS was tested. Twelve immersions of media/day was optimum. Higher culture growth rates resulted in lower carvone levels/culture; however, overall carvone levels/vessel increased due to greater biomass production.
Morphological Variation in Black Cohosh—A Threatened Medicinal Plant
Authors: Gardner Zoë E. , Lueck Lorna , Craker* Lyle E.
Published: February 2019

Black cohosh [Actaea racemosa L.; syn. Cimicifuga racemosa (L.) Nutt], a plant native to the eastern United States, is believed to have been used as a medicinal by Native Americans for thousands of years. Currently, the root of the species is popular as a herbal remedy for the relief of menopausal symptoms. Recent estimates suggest that over 90% of the black cohosh sold is collected from the wild, resulting in an unsustainable harvest of ≈9 million individual plants per year. This study investigated the morphological variation of the plant at the population and species levels to assist plant breeders working on domestication and government agencies responsible for conservation of the species. Examination of leaves and flowers suggest morphological of the species is relatively low, but that several populations have unique morphological characteristics.
Synthesis of n-Benzylhexadecanamide as a Standard for Quantifying Macamides in Maca
Authors: McCollom* Megan , Gafner Stefan , Craker Lyle E.
Published: February 2019

Maca (Lepidium meyenii Walp.), a root crop similar to radish, has been consumed in Peru for thousands of years as a food and medicine. Medicinally, the plant is used to increase human and livestock stamina and to ameliorate fertility problems associated with living at the high elevations in which the plant grows. The reputation of maca as a fertility and libido enhancer has increased the popularity of the plant in the United States and other Western countries. Constituents of interest in maca include fatty acids and macamides, but to evaluate the quality of maca products and raw material, fatty acid and macamide standards are required. While fatty acid standards are obtainable, macamide standards are not commercially available. In this study, one major macamide, n-benzylhexadecanamide, was synthesized with high yields using benzylamine and palmitoyl chloride as starting materials. The process, which was a relatively easy, one-step synthesis, could be used also to obtain other macamides without going through a time-consuming isolation. The major macamides in extracts of dried, ground maca sourced from vendors in the United States and Peru were identified and quantified by LC-UV/MS using n-benzylhexadecanamide as a standard compound.
Growth and Yield of Six Medicinal Herbs in Response to Mulch Type
Authors: Davis* Jeanine M. , Cox George B.
Published: February 2019

Weeds are a major concern in the production of many medicinal herbs. Weeds can interfere with the growth of the herb, reducing yields of foliage, flowers, and roots. The presence of weeds in the harvested herb can lessen the value of the herb or render it unmarketable. Weed control on medicinal herbs is difficult because there are few herbicides cleared for use and many herbs are organically grown. In this study, we examined the use of white and black plastic mulches to control weeds in the production of six medicinal herbs in the northern piedmont region of North Carolina. The herbs were grown for 2 years on raised beds with drip-irrigation. The beds were left bare or covered with black plastic mulch or white plastic mulch. The herbs grown were Arnica chamissonis, Echinacea angustifolia, Echinacea purpurea, Leonurus cardiaca, Scutellaria lateriflora, and Spilanthes oleracea. Transplants were field set in May and June. Depending on the particular herb, foliage, and flowers were harvested during both growing seasons and roots were harvested at the end of the second season. Both plastic mulches provided excellent weed control compared to the bare ground treatment. A. chamissonis flower yields were reduced when plants were grown with either plastic mulch. Growth and yield of E. angustifolia, L. cardiaca, and S. lateriflora were unaffected by any mulch treatment. In contrast, total season yields of E. purpurea tops (stems, leaves, and flowers) and roots were higher with both plastic mulches than with the bare ground treatment. Root yields of S. oleracea were higher with the bare ground treatment than with either mulch, but top yields were unaffected by treatment.
Propagule Type and Planting Time Affect Subsequent Growth of American Mayapple
Authors: Cushman* Kent , Maqbool Muhammad
Published: February 2019

The American mayapple (Podophyllum peltatum L.) is native to eastern North America and its leaves contain the pharmaceutical compound podophyllotoxin. Podophyllotoxin is used in the manufacture of several types of drugs used in the treatment of cancer, arthritis, and various skin conditions. With leaves being a renewable resource, the plant is a candidate for cultivation by growers of specialty crops. We are investigating strategies of establishing mayapple in field plantings. Rhizome segments were harvested from the wild and immediately transplanted to raised beds in northern Mississippi. There were three planting times, Fall 2000, Spring 2001, or Summer 2001, and three propagule types: (1) two-node rhizome segments with a terminal node and its adjacent one-year-old node, referred to as Nt+N1, (2) one-node segments with a single node, other than Nt, of unknown age, referred to as Nx, or (3) one-node segments with a single terminal node, referred to as Nt. Each spring, shoots emerged from the ground in March, grew during April, and senesced throughout May. Shoot emergence, leaf area, leaf dry mass, and shoot height were recorded each spring. Plant growth and performance can be ranked as follows. EXCELLENT: Spring-planted Nt+N1. GOOD: Fall- and summer-planted Nt+N1; fall-, spring-, and summer-planted Nx; and spring-planted Nt. FAIR: Fall-planted Nt. POOR: Summer-planted Nt. We can now recommend all three planting dates, but in the following order of preference: spring > fall > summer. We can also recommend two of the three propagule types, also in the following order of preference: Nt+N1 > Nx. The Nt propagules performed adequately when planted during fall or spring, but they did not perform well when planted during summer.
Crop Diversification in Ontario: Adaptation of Chives
Authors: McKeown* Alan W. , McDonald Mary Ruth , Bakker Cathy J. , Kooi Kevin Vander
Published: February 2019

Chives, (Allium schoenoprasum) consumption and production are increasing in Ontario. Rust (Puccinia allii F. Rudolphi) has been a problem with some chive cultivars for some growers, and in Ontario, basic information on production is nonexistent. The objectives were to identify cultivars with high yields, disease resistance and winter survivability. Plantings of six cultivars of chives were established in 2002 and 2003 in two contrasting environments, on organic (Kettleby) and mineral (Simcoe) soils; and one cultivar of garlic chives (A. tuberosum) at Kettleby. Leaves were harvested to a length of 30 cm, weighed and assessed for visible signs of rust. In Spring 2003, the number of dead plants was recorded to determine the overwinter survivability of each cultivar. Performance varied among cultivars and between locations. In Simcoe, Staro produced the highest yield in 2002 while generic (unnamed) chives produced the highest yield in the second year. In Kettleby, yield was similar among cultivars in 2002 but in 2003 generic chives produced the highest yield. Overwinter survival also varied between locations and second season yields were much higher in Kettleby. Less snow cover and subsequent winter injury is a possible explanation for the lower yields and poorer winter survival in Simcoe. No symptoms of rust were found in either location. Chives are a viable crop in Ontario, and appear to have different adaptability to regional soils and climates.
Susceptibility of Five Apple Cultivars to Browning
Authors: Milani* Jafar
Published: February 2019

Phenolic compounds and polyphenol oxidase (ppo) activity in five apple cultivars were assessed in relation tobrowning susceptibility. The degree of browning was determined by measuring brown pigments in homogenised pulp. The analysis variance of the browning rate, polyphenol content and ppo activity showed that only the effect of cultivar was significant while the interaction of location and cultivar not significant. Comparison of means (Duncan) classified the cultivars in view of browning rate in three groups (P < 0.01): Strong (Red Delicious), weak (Arangeh and Granny Smith), and mid (Golden Delicious). Arangeh was the superior variety due to its highest total soluble solids and lowest browning rate.
Contamination of Apple Fruit with Diphenylamine During Storage
Authors: Forney* Charles F. , Song Jun , Jordan Michael A.
Published: February 2019

Apple fruit are treatmented with diphenylamine (DPA) in the form of a postharvest dip to prevent the development of storage scald. However, DPA residues have been detected on apples not treated with DPA, which is problematic in markets where DPA residues are not acceptable. The objective of this study was to identify sources of DPA contamination and evaluate the effectiveness of ozone to reduce contamination. Concentrations of DPA in the atmosphere of commercial storage rooms was monitored during the storage season and the adsorption of DPA onto wood and plastic bin material, plastic bin liners, foam insulation, and apple fruit was assessed. DPA was sampled from headspace with solid phase micro extraction using 65 μm polyacrylate micro fibers and analyzed using GC-MS. The effectiveness of gaseous treatments of 300 and 800 ppb ozone to reduce DPA contamination on apple fruit and bin material was also determined. DPA was found to volatilize from treated apples and bins into the storage room air, where it was adsorbed onto storage room walls, bins, bin liners and other fruit. DPA was found in the atmosphere of storage rooms containing apples that were not treated with DPA. Wood and plastic bin material, bin liners, and foam insulation all had a high affinity for DPA and were determined to be potential sources of contamination. Ozone reacted with DPA and following gaseous ozone treatments, off-gassing of DPA from wood and plastic bin material and bin liners was reduced. However, ozone was not effective in removing all DPA in contaminated materials and was ineffective in removing DPA from contaminated apples. Due to the pervasive and persistent nature of DPA, fruit should be handled and stored in facilities where DPA is not used to prevent contamination of fruit.
Purification and Characterization of a Glutathione S-Transferase from Pome Fruits
Authors: MacLean* Dan D. , Murr Dennis P. , DeEll Jennifer R.
Published: February 2019

Glutathione S-transferase (GST) is a ubiquitous and constitutive enzyme that is involved in numerous cellular activities including the amelioration of oxidative stresses caused by the presence of xenobiotics and reactive oxygen species. In the present study, a glutathione S-transferase was extracted, purified, and partially characterized from two types of pome fruits. Pear (Pyrus × communis L., cultivar D'Anjou) and apple (Malus × domestica Borkh., cultivar Delicious) fruit were tested. The glutathione S-transferase was extracted using traditional methods, and purified using a combination of ammonium sulfate precipitation, dialysis, and GST-specific affinity chromatography. The GST enzyme was subsequently eluted from the column and concentrated prior to characterization studies. A purified fraction from the column was loaded onto an SDS-PAGE gel, and resulted in a single band with an apparent molecular weight of ≈26 kDa. This band was excised and used for MALDI-TOF/MS peptide mass fingerprint studies, and also served to confirm the apparent mass of the protein (25969 Da). The ExPASy software was used for the peptide mass fingerprint study, where the digest of the GST using trypsin was compared to a theoretical digest of an Arabidopsis GST, and resulted in two peptides of significant mass homology. The purified GST was also tested for enzyme activity using the standard assay substrate of 1-chloro-2,4-dinitrobenzene and reduced glutathione. Total GST protein extracted from `D'Anjou' pear was 0.532 mg·mL-1, while `Delicious' apple contained 0.127 mg·mL-1. The activity of GST enzymes may play a role in minimizing oxidative stress injury in stored pear and apple tissues.
The Relationship Between the Production of Volatile Aromas and the Induction of Ethylene in Apple Fruits
Authors: Niu* Zimian , Zhang Dapeng , Zhao Hongyu , Rom Curt
Published: February 2019

The volatile aromas from the fruits of `Naganofuji No.2' apple (Malus domestica Mill.) were determined by gas chromatography (GC) and combined GC-mass spectrometry (GC-MS) after different temperature conditions. The fruits from CA storage were sealed in glass and the volatiles in the headspace were determined. Eleven compounds of four chemical classes from active carbon absorbed samples were measured and three of them—tormic acid pentyl ester, butanoic acid-1-methyl ethylester and 4-hydroxy-3-methyl-2-butanone, were identified at 20 °C, but not at °C. Under 20 °C condition, the contents of three volatiles increased from 1 hour and reached to their peaks at the 4th to 7th hour. The content of ethylene reached its peak at 4 hours and changed synchronically with the other volatiles during the experiment. The content of ethylene was significantly positively correlated with the contents of volatile aromas (r = 0.96-0.98, P ≤ 0.01). Under °C condition, the content of ethylene was significant lower than that of at 20°C and there was no ethylene peak produced during experiment. When the fruits were treated with ethephon (0.1 mg·L-1) at 5°C, the content of ethylene increased greatly. The highest level of ethylene was found at 4 to 7 hours and the peaks of volatiles also appeared at 7 hours or 10 hours after the treatment. It was suggested that the production of ethylene in fruits could be thought as an indicator of some volatile aromas.
Preliminary Examination of the Impact of a Gardening Program on Confidence, Physical Activity, Fruit and Vegetable Consumption, and Quality of Life
Authors: Lin Mu-Chuan , Shoemaker* Candice , Gyurcsik Nancy
Published: February 2019

Older adults are not sufficiently physically active and do not consume sufficient fruits and vegetables to achieve health benefits, such as an improved health-related quality of life (HRQL). As a result, an innovative gardening intervention, comprised of stretching exercises, the teaching of home garden knowledge and skills, and the preparation and taste testing of fruits and vegetables, was developed to target increased: (a) confidence to garden and to consume fruits and vegetables, (b) physical activity, (c) fruit and vegetable consumption, and (d) HRQL. Seven older adults, aged 60 years or older, participated in the gardening intervention and 10 older adults participated in the control group during the fall. Measures of confidence, physical activity (i.e., gardening), fruit and vegetable consumption, and HRQL were obtained at baseline and at the end of the 10-week program. Findings revealed that, at baseline, intervention participants had significantly higher confidence to garden compared to control participants but at end-program intervention and control participants did not significantly differ in any of the outcome variables. Bivariate findings also revealed that intervention participants who had higher confidence to garden or to consume fruits and vegetables at baseline also gardened more at end-program. Thus, interventions targeting confidence to garden and to consume fruits and vegetables may be effective in improving gardening (i.e., physical activity) behavior. Findings also suggest that seasonal change may be one influential moderator of the gardening program on confidence and gardening and fruit and vegetable consumption behavior change. Future research should examine the impact of the program in different seasons to clarify the effects.
Expanding Outreach via Colorado Master Gardener Clinics
Authors: O'Meara* Carol A. , Badertscher Kerrie B.
Published: February 2019

Data supports the success of Colorado Master Gardener sm (MG) of Boulder County outreach beyond the Cooperative Extension office at outlying clinic sites. Initially unique in Colorado, MG plant clinics at area nurseries and garden centers has gained acceptance in other counties of Colorado. Exploration of benefits and investments for programs interested in expanding outreach to the public are discussed to provide a blueprint for clinics start-up. MG clinics are set up to provide answers to questions from the public on Friday through Sundays from April through mid-July. This schedule, coupled with the Monday through Friday MG desk hours, provides seven day per week access to the public during the busiest part of the growing season. Clinics are conveniently located in all county communities at Green Industry locations. Participating businesses consider the clinics a benefit worth investing IN and justification of sites is uniform. Additional single-day clinics have spun off as an addition to fixed clinic schedule. High requirement of staff time, increased sample load and resource investment is offset by the benefits of increased visibility of program in the community leading to increased recruitment of volunteers. Knowledge gained by the public has brought about measurable positive changes in pesticide use and responsible cultural practices. Volunteer retention is favorably affected with increased flexibility of scheduling opportunities and communications. Information on setting up clinic sites, what the sites receive, staff time and services requirements, and refinements as a result of clinic survey will be given.
Assessing Penn State Master Gardener Use of Teaching Tools
Authors: Wehry* Rebecca H. , Kelley Kathleen M. , Bilik Antoinette
Published: February 2019

A direct-mail survey was administered to gain perspective of the audio/visual tools Penn State Master Gardeners currently use to teach their clientele and their comfort level with using computers and accessing the Internet. Of the 700 surveys that were distributed to active MG during the month of November 2002, 386 completed surveys were returned. Male MG were more likely to use slides (44%) and less likely to use posters (15%) than female MG to teach consumer clientele (29% and 26%, respectively). Participants from single-adult households (20%) were more likely to use PowerPoint than those from households with two or more adults (11%). A greater percentage of participants, 54 years of age and younger reported having Internet access at their home (90%) and at work (42%) compared to MG age 55 years and older (75% and 16%, respectively). Over half of the younger MG (53%) responded that they were “very comfortable” with using the Internet to search for information compared to 37% of their counterparts. Currently MG use computers as a teaching tool on a limited basis, with younger MG possessing a greater degree of comfort with both the computer and Internet. By teaching MG how to use this technology the ability to reach a large audience can increase, thus further extending the reach of this component of Cooperative Extension. Though use of high tech methods to deliver information is continually gaining momentum, the number of MG who use less technical teaching tools should also be considered and appropriate tools should remain available.
Master Gardener-led Projects in Southern Nevada
Authors: O'Callaghan* Angela , Brown Florence , McConnell Denise , Morris Robert
Published: February 2019

Southern Nevada Master Gardeners (MGs) donate 50 hours annually to educational and service projects. These volunteers respond to community needs by developing and staffing horticultural projects under UNCE supervision. In Las Vegas, 20 such projects exist. Some are more energy and information intensive than others. Mojave Guides are docents at the Desert Demonstration Garden, a part of the Las Vegas Springs Preserve, not Extension. They commit to a shift at the garden, providing information to visitors. While they are directly supervised by garden staff, the hours they contribute are Master Gardener hours. These volunteers receive training in desert flora from gardens staff and participate in seminars on selected topics. The MG Orchard Team operates a teaching orchard at the Center for Urban Water Conservation in North Las Vegas. These volunteers maintain hundreds of fruit trees and grape vines. They receive training on topics related to fruit trees and orchard management. This project began in 1996. Since 2002, they have been formalizing their organization using the logic model and SWOT analysis. Many members work weekly at the orchard and take the produce to a local farmers market. This raises funds for the orchard and is an opportunity to teach the community about desert horticulture. Project PLANT volunteers work at the Red Rock National Recreation Area visitor center and grounds. They are docents who also learn about and maintain the native plants there, and prevent infestations of invasive weeds which threaten the area. Their monthly meetings include training on topics related to the project. These projects are successful because of the MGs themselves. They grew out of interest and continue because the volunteers have drawn commitment from others.
Research on Transformation Conditions using Malus hupenensis var. `Pingyitiancha'
Authors: Shen* Xiang , Wei Zhenlin , Guo Ling
Published: February 2019

`Pingyitiancha' has good agricultural traits and is an important rootstock for apples. It was studied for Kam, Cef and Carb concentrations, precultural times, active medium of A.tum, Ca++ concentration, mixed inoculation times of AgNO3, and PVP delay selection times for getting transgenic `Pingyitiancha' stock with more resistance to drought and salt. It was demonstrated that the highest transformation frequency was obtained with 200 mg·L-1 Cef as an A.tum restraining antibiotic, 8 mg·L-1 Kam as a selection antibiotic, GCJ8 active medium, a precultural of 2 days, 5 Ca++ concentrations in preculture and coculture medium compared with standard MS medium, immersed in A. tum as OD600 for 0.5 to 1 min., 4 mg·L-1 AgNO3 and 0.7% PVP as an anti-oxidation compound to reduce hydroxybenzene oxidation and delay selection for 5 days by using `Pingyitiancha' apex shoots as explants. Using mediate of A. tum strain LBA4404 under conditions mentioned above and same explants, the HVA1 gene were transformed into `Pingyitiancha' under the control of CaMV35S promoter and obtained Kam resistance regeneration plants. Six transgenic plants were confirmed by PCR and subsequent dot blot methods.
Utilizing Tobacco Greenhouses for Producing Plants for Environmental Restoration
Authors: Bell Andrew C. , Peet* Mary M.
Published: February 2019

Environmental restoration of streams and wetlands in North Carolina is creating a growing demand for commercially available native plant material. Recent changes in the tobacco industry have resulted in decreased production leaving some tobacco greenhouses, once utilized for a few months, empty year-round. Identifying alternative crops that can be grown in tobacco greenhouses will provide valuable income to economically distressed tobacco growers. The floatation system (sub-irrigation) employed in the production of tobacco transplants in greenhouses is similar to that utilized by some native plant nurseries to produce wetland and riparian species. Local production of this plant material can enhance restoration project goals by increasing utilization of regional germplasm in this industry and reducing the risk of importing exotic pests with material shipped from out-of-state. To research these possibilities, we constructed a demonstration tobacco greenhouse with multiple float beds. Three commercially available media, including a tobacco seedling mixture, were tested. No differences were observed among the plants grown in different media. After one growing season, we have identified close to 20 species, woody and herbaceous, that can be successfully grown in a traditional tobacco greenhouse with minimal input or alternation to the structure or normal production practices. Additional research is needed, however, to address optimal production criteria.