bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioactivity of Volatile Alcohols on the Germination and Growth of Radish Seedlings
Authors: Stutte G.W. , Eraso I. , Anderson S. , Hickey R.D.
Published: February 2019

A series of experiments were conducted to determine the sensitivity of radish to four light alcohols (ethanol, methanol, 2-propanol, and t-butanol) identified as atmospheric contaminants on manned spacecraft. Radish (Raphanus sativus L. `Cherry Bomb' Hybrid II) seedlings were exposed for 5 days to concentrations of 0, 50, 100, 175, 250, and 500 ppm of each alcohol and the effect on seedling growth was used to establish preliminary threshold response values. Results show a general response-pattern for the four alcohol exposures at threshold responses of 10% (T10), 50% (T50) and 90% (T90) reduction in seedling length. There were differences in the response of seedlings to the four alcohols, with the T10 for t-butanol and ethanol (25 to 40 ppm) being 3 to 5× lower than for methanol or 2-propanol (110 to 120 ppm). Ethanol and t-butanol exhibited similar T50 values (150 to 160 ppm). In contrast, T50 for methanol (285 ppm) and 2-propanol (260 ppm) were about 100 ppm higher than for ethanol or t-butanol. Chronic exposures to 400 ppm t-butanol, ethanol or 2-propanol were highly toxic to the plants. Radish was more tolerant of methanol, with T90 of 465 ppm. Seeds did not germinate at the 500 ppm treatment of t-butanol, 2-propanol, or ethanol. There were significant differences in projected performance of plants in different environments, dependent upon the regulatory guidelines used. The use of exposure guidelines for humans is not applicable to plant systems.
Plant Mass and Yield of Broccoli as Affected by Soil Moisture
Authors: Gutezeit Bodo
Published: February 2019

The effect of water supply on total mass and yield of broccoli (Brassica oleracea L. var. italica, `Emperor') was examined in an experiment carried out in a microplot field installation on three soil types: Gleyic Cambisol (sand) and Eutric Fluvisol (flood-plain loam) in spring and fall and on a Haplic Phaeosem (loessal loam) in fall. Soil moisture levels were established by irrigation under the following replacement protocols: 14 mm whenever the limit of 75% vol of the available soil water (ASW), 14 and 28 mm whenever the limit of 55% vol of ASW, and 14, 28, and 42 mm whenever the limit of 35% vol of ASW were reached. The highest total plant mass was achieved by irrigation at 75% vol of ASW on the sandy soil in spring cultivation, and at 55% vol of ASW (in doses of 28 mm) on the flood-plain loam in fall cultivation. The highest marketable yield (head mass) was obtained on the sandy soil at 55% vol of ASW (in doses of 14 mm) for both spring and fall production. The total plant mass and head mass was only significantly affected by reduced soil moisture at 35% vol of ASW in spring. At 75% vol of ASW, irrigation with 14 mm always resulted in reduced headmass. In fall, yield was not affected by soil moisture depletion or soil type. For the production of broccoli, it is recommended that irrigation be started when soil moisture falls below 55% vol of ASW, followed by a water application rates of either 14 or 28 mm.
Dynamic and Traditional Greenhouse Climate Regimes: Influx of Thrips (Thysanoptera)
Authors: Jakobsen Lene , Brogaard Michael , Enkegaard Annie , Brødsgaard Henrik F. , Aaslyng Jesper M.
Published: February 2019

Dynamic climate regimes have been developed mainly to reduce energy consumption in the greenhouse, and this has been the main reason for their adoption by growers. During recent years, Danish growers have observed that problems with pests have diminished since they changed from the traditional rigid climate regime to a dynamic regime. The trend has also been observed in scientific experiments testing different dynamic climate regimes. The present experiment shows that the influx of thrips from outside into the greenhouse was reduced by 40% under a dynamic climate regime compared to a traditional rigid regime, and that this was related to the opening degree of the vents. Vents were open on average 7% under the dynamic regime and 33% in the traditional climate. The influx of thrips was linearly correlated with density outside the greenhouse (P < 0.0001) and with opening degree of the vents (P = 0.0001).
Improvement of In Vitro Culturing of Habanero Pepper by Inhibition of Ethylene Effects
Authors: Santana-Buzzy Nancy , Canto-Flick Adriana , Iglesias-Andreu Lourdes G. , del C. Montalvo-Peniche María , López-Puc Guadalupe , Barahona-Pérez Felipe
Published: February 2019

The in vitro production of ethylene and its effects on the development of Habanero pepper (Capsicum chinense Jacq.) plantlets were evaluated using nonventilated containers (NVCs) and ventilated containers (VCs). Shoots of Habanero pepper between 0.5 and 1.0 cm of height were cultivated in Magenta culture boxes and samples of the headspace atmosphere were taken every four days during the previously established culturing time of 40 days. The presence of ethylene was detected in the NVCs and produced a negative effect on the development of plantlets. In a second phase of this work, the effect of silver nitrate (AgNO3) and cobalt chloride (CoCl2) on ethylene production was evaluated during in vitro development of Habanero pepper plantlets. Concentrations of 50, 300, and 500 μm of each ethylene inhibitor were used in the culture medium. Although cobalt chloride partially inhibited the production of ethylene during in vitro culture of this species, at low concentrations the plantlets presented some degree of vitrification and the highest concentration proved to be toxic for the plantlets. Silver nitrate added to the culture medium did not inhibit ethylene production, however, it did inhibit the effect of this hormone on the plantlets. In fact, when high concentrations of silver nitrate were used (300 μm), high amounts of ethylene were detected in the headspace of the vessels and plantlets were actually healthier.
EFFECTS OF GA4+7 AND BA APPLICATION ON POSTPRODUCTION QUALITY IN `SEADOV' POT TULIP FLOWERS
Authors: Kim Hye-Ji , Miller William B.
Published: February 2019

The effect of GA4+7 plus benzyladenine (BA) on postproduction quality was investigated in `Seadov' tulips (Tulipa gesneriana). Potted tulips at half-colored bud stage or full-bloom stage were sprayed with a range of GA4+7 plus BA, and placed in a simulated consumer environment (SCE) in order to determine effectiveness of the compound at each stage. Regardless of plant stage, treatment with GA4+7 plus BA effectively improved individual flower longevity and whole plant longevity in the range of concentrations tested. GA4+7 plus BA had a strong effect on enhancing flower longevity when sprayed to mature (fully colored) buds, and a lesser effect on immature (green) buds, and whole plant longevity increased with higher doses of GA4+7 plus BA. When applied to open flowers, however, concentrations over 50 mg·L–1 reduced individual flower and whole plant longevities relative to lower concentrations resulting from unwanted full-opening of older flowers and exaggerated gynoecium growth. Concentrations as low as 10 mg·L–1 significantly increased longevity of tulip flowers of all age classes. The effects of enhancing postproduction quality of `Seadov' pot tulips were primarily derived from the BA component of the compound.
MICRONUTRIENT AND HEAVY METAL CONCENTRATIONS IN FIELD-GROWN LETTUCE
Authors: Jiang Zhongchun
Published: February 2019

Information about micronutrient concentrations of plants in general can be found in botany and plant physiology textbooks, but micronutrient concentrations in field-grown lettuce is hard to find and so are concentrations of heavy metals. Lettuce consumers may be concerned with heavy metal concentrations and information about heavy metal concentrations may help consumers make a choice. This study examined the concentrations of eight micronutrients and five heavy metals in field-grown lettuce with different fertilization programs. Under the field conditions, different NPK fertilizers and fertilization rates did not differ in the leaf concentrations of micronutrients and heavy metals. The overall means of Fe, Na, Mo, and Ni concentrations in the lettuce were 663, 710, 0.9, and 1.9 μg·g–1 of dry leaves, respectively. These values were significantly higher (over 500% greater) than the values found in textbooks for plants in general. Mean Mn, Cu, B, and Zn concentrations were 55.5, 7.3, 23.7, and 28.4 μg·g–1 of dry leaves, respectively, which are in general agreement with textbook values. Mean concentrations of heavy metals Cd, Co, Cr, and Pb were 1.5, 1.0, 2.9, and 4.5 μg·g–1 of dry leaves, respectively, whereas mean Al concentration was 498.5 micrograms per gram of dry leaves. These results indicate that concentrations of some elements in lettuce leaves can be high under certain field conditions. It would be beneficial for lettuce growers and consumers to have this information.
TRANSPLANTING AND ORGANIC MULCH AFFECT GAS EXCHANGE AND GROWTH OF FIELD GROWN RED OAK (QUERCUS SHUMARDII BUCKLI.)
Authors: Bonds Amber , Montague Thayne
Published: February 2019

Balled in burlaped is a common method for moving large trees into landscapes and affects of transplanting on tree gas exchange and growth has been documented. Organic mulch provides many benefits and is often recommended for landscapes. Because little research has been conducted on affects organic mulch has on gas exchange and growth of transplanted and non-transplanted trees, this research investigated the effects transplanting and organic mulch have on gas exchange and growth of field grown red oak (Quercus shumardii) trees. In March 2003, 12 multi-trunked trees were selected from a tree farm near Lubbock, Texas, and six trees were dug using a tree spade and placed in their original location. Mulch at a depth of 10 cm was placed around the rootball of 3 transplanted and 3 nontransplanted trees and maintained at this depth the remainder of the experiment. Over the next three growing seasons predawn leaf water potential and midday stomatal conductance were measured on each tree every 1 to 3 weeks. At the end of every growing season shoot elongation, stem caliper and subsample leaf area were recorded. Our data indicates transplanting has a negative affect on gas exchange and growth of red oak. Each growing season gas exchange, shoot growth, and subsample leaf area were less for transplanted trees when compared to nontransplanted trees. Mulch also influenced gas exchange and growth of these trees. For nontransplanted trees with mulch, gas exchange and growth were reduced when compared to nonmulched, nontransplanted trees. For transplanted trees with mulch, predawn leaf water potential was less negative and subsample leaf area was greater when compared to transplanted trees with out mulch.
INFLUENCES OF SUBSTRATES ON ROOTING CLEMATIS SOCIALIS STEM CUTTINGS
Authors: Johnson C.N. , Eakes D.J. , Wright A. N. , Sibley J.L , Bruner L.L.
Published: February 2019

Clematis socialis Kral, commonly known as the Alabama Leatherflower, is an endangered species with only six known populations in northeast Alabama and northwest Georgia. Cutting propagation of the species will aid in establishing additional self-sustaining populations and provide genetic material for future hybridization and genetic preservation. Such research would also benefit growers, especially native nurseries, who wish to produce this species commercially for its ornamental value. Several experiments were performed to determine the effects of four non-amended substrates on root initiation, root growth, and survival of C. socialis stem cuttings. The four substrates tested included sand, perlite, vermiculite, and a 1 peat (P): 1 pine bark (PB): 1 sand (S) mix (by volume). Some of the best results in the preliminary experiments in 2000 were observed when 2 to 3 node cuttings kept under shade and treated with higher IBA/NAA concentrations were used. In 2004, there was a correlation between root growth and cutting survival and particle size of the substrates. Cuttings rooted in the finer-particle substrates sand and vermiculite had higher cutting survival, root growth, root number, and root quality than those rooted in perlite and the 1 P: 1 PB: 1 S mix. Sand, perlite and vermiculite consistently outperformed the 1 P: 1 PB: 1 S mix which had some of the lowest growth data means. Sand was among the highest performing substrates in all years and it is the most inexpensive and readily available making it the most logical substrate for rooting C. socialis stem cuttings.
FATE AND MOVEMENT OF NO3– N AS A RESULT OF STAGED LEACHING IRRIGATION EVENTS AND FERTILIZER SOURCE DURING POTATO PRODUCTION IN NORTHEAST FLORIDA
Authors: Worthington Christine M. , Hutchinson Chad M.
Published: February 2019

The St. Johns River has been identified by the state of Florida as a priority water body in need of restoration. Best Management Practices were evaluated for potato (Solanum tuberosum L. `Atlantic') production in the Tri-County Agricultural Area to reduce nitrate run-off from about 9,300 ha in production. Objectives of this study were 1) determine the influence of soluble and controlled release fertilizer (CRF) and timing of leaching irrigation on nitrate leaching and 2) compare yield and quality of the potato crop fertilized with either a soluble or controlled release nitrogen fertilizer in a seepage irrigated production system. The experiment was a split-split plot with four replications. Main plots were irrigation events (0, 2, 4, 8, and 12 weeks after planting, (WAP)), nitrogen source and rates included (ammonium nitrate (AN) 224 kg·ha–1 or controlled release fertilizer (CRF) 196 kg·ha–1). About 7.6 cm of water was applied at each irrigation event and surface water runoff collected. CRF decreased NO3-N loading by an average of 35%, 28%, and 32% compared to AN fertilizer during the 2, 8, and 12 WAP irrigation events, respectively, compared to AN. Plants in CRF treatments had significantly higher total and marketable tuber yields (30 and 25 t·ha–1) compared to plants in AN treatments (27 and 23 t·ha–1), respectively. Plants in the CRF treatments also had significantly higher total and marketable yields in 2005 (28 and 23 t·ha–1) compared to plants in AN treatments (25 and 21 t·ha–1), respectively. CRF was an effective alternative to conventional soluble forms of fertilizer maintaining yields and protecting natural resources from nonpoint source pollution.
LYCOPENE CONTENT OF ORGANICALLY GROWN TOMATOES
Authors: Perkins-Veazie P. , Collins J.K. , Roberts W.
Published: February 2019

Reports on the lycopene content of tomatoes vary widely with country and source of fruit (field, greenhouse, retail). This study was done to compare the lycopene content of organically grown tomatoes, and to compare fully red fruit to those ripened after harvest. Thirteen tomato cultivars (12 beefsteak and one Roma type) were planted in land designated as transitional organic and fertilized with organic poultry litter. No additional fertilizer was applied. Pesticides approved for organic use were applied as necessary. Fruit at the turning to firm red stages were harvested and held at 20 to 28 °C until the soft red stage was reached (about 2 to 8 days). Day 0 fruit at pink to soft red stages was harvested at the same time. Multiple harvests were made for 6 weeks, until 10 fruit per cultivar and ripeness stage and storage treatment were obtained. Lycopene content of firm red and soft red fruit were similar, and was 50 to 65 mg·kg–1 for all the round fruit types, and 115 mg·kg–1 for the Roma type. Fruit ripened after harvest without ethylene were able to obtain similar levels of lycopene, even in those fruit harvested with just a trace of color. `Sunmaster' and `Solar Set' tomatoes grown organically were similar in lycopene content to those grown in previous years in a conventional production system. These results show that organically grown tomatoes can achieve normal to high levels of lycopene. Tomatoes ripened after harvest without ethylene can achieve the lycopene content of fruit harvested fully ripe.
OKRA IN-ROW SPACING ALTERS PLANT GROWTH AND YIELD IN SOUTHERN FLORIDA
Authors: Olczyk Teresa , Cushman Kent , Klassen Waldemar
Published: February 2019

Okra (Abelmoschus esculentus) is grown as a direct-seeded cash crop at high plant populations (>87,000 plants/acre) on calcareous soils in Homestead, south Florida. A study was established in a commercial field in May 2005 to evaluate if high populations translated to higher yields. Seedlings were thinned to within-row spacings of 2, 4, 6, 8, and 10 inches in rows set 3 ft apart (87120, 43560, 29040, 21780, and 17420 plants/acre). Harvest data was collected from 29 July to 30 Sept. 2005 (26 harvests) from 10 ft of the center row within plots 15 ft long and 3 rows wide. Decreasing plant density resulted in decreasing plant height early in the season and increasing height late in the season. Density affected stem caliper with a clear trend of decreasing density and increasing caliper. Early, mid-, and total yields by weight (boxes/acre) were not affected by density, but plants at the lowest density produced 55% more late yield than plants at the highest density. Plants at the lowest density produced 30% fewer early pods and 31% more late pods than plants at the highest density. Decreasing plant density resulted in increasing average pod weight for early, late, and total harvests by as much as 14% to 18%. With inexpensive open pollinated cultivars such as `Clemson Spineless 80', there seems little economic incentive to reduce plant populations below what is commonly used in the Homestead area. Growers should not be alarmed, however, if plant stands are reduced to some extent after seeding.
DEPTH AND WIDTH OF THE WETTED ZONE AFTER LEACHING IRRIGATIONS ON A SANDY SOIL
Authors: Farneselli Michela , Studstill David W. , Simonne Eric H. , Hochmuth Bob
Published: February 2019

The quantitative assessment of nitrate-nitrogen (NO3-N) leaching below the root zone of vegetable crops grown with plasticulture (called load) may be done using deep (150-cm) soil samples divided into five 30-cm long subsamples. The load is then calculated by multiplying the NO3-N concentration in each subsample by the volume of soil (width × length × depth, W × L × D) wetted by the drip tape. Length (total length of mulched bed per unit surface) and depth (length of the soil subsample) are well known, but W is not. In order to determine W at different depths, two dye tests were conducted on a 7-m deep Lakeland fine sand using standard plasticulture beds. Dye tests consisted in irrigating for up to 38 and 60 hours (11,756 and 18,562 L/100 m of irrigation, respectively), digging transverse sections of the raised beds at set times and taking measurements of D and W at every 30-cm. Most dye patterns were elliptic elongated. Maximum average depths were similar (118 and 119 cm) for both tests despite differences in irrigation duration and physical proximity of both tests (100 m apart in the same field). Overall, D response (cm, both tests combined) to irrigation volume (V) was quadratic (Dcomb.avg = –2 × 10–7V2 + 0.008V + 34), and W responses (applying maximum and average values, Wmax and Wmean) to D (cm) were linear (Wmax = –0.65D+114: Wmean = –0.42D + 79). Predicted Wmax were 104, 84, 64, 44, and 25 cm at 30-cm depth increments. These preliminary values may be use for load calculations, but are likely to over-estimate load as they were determined without transpiring plants and may need to be adjusted for different soil types.
Taxonomic Relationships of A Rare Cucumis Species (C. hystrix Chakr.) and Its Interspecific Hybrid with Cucumber
Authors: Zhuang Fei-Yun , Chen Jin-Feng , Staub Jack E. , Qian Chun-Tao
Published: February 2019

The current Cucumis taxonomic classification places C. hystrix Chakr. in subgen. Cucumis based on its morphological similarities to cucumber (C. sativus L., 2n = 14). However, the chromosome number of C. hystrix was identified as 2n = 24, the same number as in subgen. Melo. Cucumis hystrix is therefore considered the first wild Cucumis species of Asiatic origin possessing 12 basic chromosomes. Thus, any research regarding its biosystematics would challenge the basic chromosome number and geographic location theories that govern the current taxonomic system. The production of the amphidiploid species (Cucumis ×hytivus Chen and Kirkbride, 2n = 38) obtained from the cross between C. hystrix and C. sativus and subsequent chromosome doubling would provide an effective means of investigating the relationship between Cucumis species with two different basic chromosome numbers. Thus, RAPD markers were used to study the taxonomic placement of C. hystrix and its interspecific hybrid with cucumber. Of the 220 arbitrary primers screened, 31 were used for analysis where 402 (96.3%) fragments were polymorphic among the germplasm examined. A UPGMA-based cluster analysis partitioned 31 accessions into two main groups [C. sativus (CS) and C. melo (CM)]. Under the similarity coefficient threshold of 0.23, these two groups can be further divided into five clusters with C. hystrix, C. ×hytivus, and C. sativus as separate clusters in the CS group. A modified taxonomic system is proposed based on these results and findings of a previous chloroplast DNA analysis with the genus Cucumis containing subgen. Cucumis with three species and subgen. Melo with six series.
Anatomical Observations of Anthocyanin Rich Cells in Apple Skins
Authors: Bae Ro-Na , Kim Ki-Woo , Kim Tae-Choon , Lee Seung-Koo
Published: February 2019

Anatomical observations of anthocyanin rich cells in `Fuji' apple skins were carried out by light microscopy and electron microscopy. Apple skins with fully developed red color had more layers of anthocyanin-containing epidermal cells than those of green skins. The density of anthocyanin was high in cells of the outer layer of the fruit skins and gradually decreased inward to the flesh. Anthocyanins were frequently found in clusters or in agglomerations that were round in the epidermal cells of the red skins. They accumulated in the inner side of developed vacuoles. Transmission and scanning electron microscopy revealed that the shapes of anthocyanins were cluster style, indeterminable forms, or complete spheres. Anthocyanin seemed to be synthesized around the tonoplast and condensed on the inward side of the vacuole. There was no distinct envelope membrane on the anthocyanin granule in the vacuoles of apple skin cells.
Four Cultivars of Japanese Barberry Demonstrate Differential Reproductive Potential under Landscape Conditions
Authors: Lehrer Jonathan M. , Brand Mark H. , Lubell Jessica D.
Published: February 2019

While japanese barberry (Berberis thunbergii DC.) is an acknowledged invasive plant naturalized throughout the eastern and northern U.S., the danger posed by its popular horticultural forms is unknown and controversial. This work analyzed the reproductive potential and seedling growth of four ornamental genotypes important to the nursery industry. Fruit and seed production was quantified in 2001, 2002, and 2003 for multiple landscape plants of B.t. var. atropurpurea, `Aurea', `Crimson Pygmy', and `Rose Glow'. The average number of seeds produced per landscape specimen ranged from lows of 75 and 90 for `Aurea' and `Crimson Pygmy' to 2968 for var. atropurpurea and 762 for `Rose Glow'. Seed production relative to canopy surface area for `Rose Glow' was similar to `Aurea' and `Crimson Pygmy' and all three cultivars were less prolific than var. atropurpurea in this regard. Cleaned and stratified seeds from var. atropurpurea, `Crimson Pygmy' and `Rose Glow' showed an average greenhouse germination rate of 70% to 75%, while `Aurea' yielded 46% germination. A subpopulation of seedlings from each genotype accession was grown further outdoors in containers for a full season to ascertain seedling vigor and development. The vigor of 1-year-old seedlings, as measured by dry weight of canopy growth, for progeny derived from `Aurea' (0.70 g) and `Crimson Pygmy' (0.93 g) was significantly less than var. atropurpurea (1.20 g) and `Rose Glow' (1.33 g). These results demonstrate that popular japanese barberry cultivars express disparate reproductive potential that, after further study, may be correlated with invasive potential. Some popular commercial cultivars may pose significantly less ecological risk than others.
Utility of Alumina-buffered Phosphorus Fertilizer for Vegetable Production
Authors: Tanaka Mayuki , Snyder Robert , Boateng John K. , Lamont William J. , Orzolek Michael D. , Brown Kathleen M. , Lynch Jonathan P.
Published: February 2019

The utility of alumina-buffered phosphorus (Al-P) fertilizers for supplying phosphorus (P) to bell pepper (Capsicum annuum L.) in soils with low-P availability was evaluated. Plants were grown at low-P fertility (about 100 kg·ha–1, low-P control; LPC), with conventional P fertilization (205-300 kg·ha–1 annually, fertilizer control; FC), or with one of two Al-P sources (Martenswerke or Alcoa) in 2001–03. The two Al-P fertilizers were applied in 2001; no additional material was applied in 2002-03. Plants grown with Martenswerke Al-P had similar shoot dry weight, root dry weight, root length, leaf P concentration, and fruit yield compared with plants grown with conventional P fertilizer in both 2002 and 2003 seasons. Bell pepper grown with Alcoa Al-P had similar shoot dry weight, root dry weight, root length, leaf P concentration, and fruit yield compared with plants grown without P fertilizer in both seasons. Alcoa Al-P continuously released bioavailable P for 2 years between 2001 and 2002, while Martenswerke Al-P continuously released bioavailable P at least 3 years between 2001 and 2003. These results indicate that some formulations of Al-P can serve as long-term P sources for field vegetable production.
Recovery of 15N Fertilizer Applied at Different Stages of Pecan Kernel Fill
Authors: Rey Alejandro , Lindemann William C. , Remmenga Marta D.
Published: February 2019

Previous research on late-season N fertilization of pecans [Carya illinoinensis (Wangehn) K. Koch] has shown significant uptake and storage of N in perennial tissues (roots, trunk, and shoots) that was used in subsequent years. The objectives of this study were to follow the fate of 15N applied at three different stages during pecan kernel fill in both the soil and tree components. In August and September 2002, 15N-labeled ammonium sulfate (9.94% 15N atom excess) was applied (56 kg N/ha) to nine pecan research trees during the early [3 days into kernel fill (DIK)], middle (25 DIK), and late (38 DIK) stages of pecan kernel fill near Las Cruces, N.M. In November 2002, about 67% of applied 15N was recovered from the soil and 13% from tree components. More 15N was recovered in nuts from the early treatment than middle or late treatments. Recoveries for May 2003 were 27% and 60% for tissues and soils, respectively. Leaf recovery increased an average of 14% in May 2003 over November 2002 leaves. More 15N was recovered from the late treatment in all tree components for May 2003 than early or middle treatments. The primary source of N for spring growth was 15N stored in perennial tissues. Fifteen months after 15N fertilizer was applied during kernel fill in 2002 about 24% remained in the soil, 28% had been used by the tree, and 48% was lost to the environment.
Horticultural Problem-solving Using Interactive Compressed Video
Authors: Panter Karen L.
Published: February 2019

Interest in horticulture in Wyoming increases each year. The vast size of the state, coupled with its low population, make travel to individual sites around the state difficult. Distance education and communication are keys to a successful horticulture Extension education program. Every summer since 2000, the University of Wyoming Cooperative Extension Service has sponsored a series of horticulture question and answer sessions. These sessions are carried out using the Wyoming compressed video system, linking campus-based specialists with Extension educators, Master Gardeners, industry, and occasionally the public, around the state. The number of sites linked with campus has varied from six to 11, depending on the year. The number of sessions held each summer has also varied, from the current six to a high of nine in 2000. Each session is 50 minutes long. The objective of these sessions is to allow personnel off-campus to show samples, ask questions, and get assistance from campus-based specialists in diagnosing various plant problems. Evaluations are done annually to determine several things: if the programs should be run again the next year, which days of the week and time of the day are best, if attendees are utilizing the information learned in the sessions, and if they feel more comfortable with their own diagnoses after the sessions. Responses vary with year, but typically 100% say the programs should continue, and greater than 75% use the information they learn and are more comfortable with their responses and their abilities to solve plant problems.
Herbicide Drift Study on White Oak Seedlings
Authors: Samtani Jayesh B. , Masiunas John B. , Appleby James E.
Published: February 2019

In 2004 and 2005, potted white oak seedlings 0.6 m in height were treated with six herbicide treatments at three concentrations, 1/4, 1/10, and 1/100× of the standard field use rate. These herbicides and their standard field use rate of active ingredient (a.i.) included 2,4-D at 1.5 kg/ha, 2,4-D + glyphosate at 0.8 kg/ha + 1 kg/ha, acetochlor + atrazine at 3.5 kg/ha, dicamba at 0.7 kg/ha, glyphosate at 1.1 kg/ha and metolachlor at 2.0 kg/ha. The seedlings were treated at three growth stages: swollen buds, leaves unfolding, and expanded leaves. A compressed air spraying chamber delivering 187 L/ha was used to apply the herbicides. After treatment, the containers were placed in an open field plot in a completely randomized design. Oak seedlings were most susceptible to herbicide injury at all concentrations, at the leaves unfolding stage. Symptoms on seedlings treated with 2,4-D and dicamba at the leaves unfolding stage included leaf cupping and rolling, leaf curling, leaf rolling downward from leaf margin, and unusual elongation at leaf tip. Glyphosate + 2,4-D applications resulted in leaf cupping, yellowing, leaf rolling downward from leaf margin and abnormal leaf tips. Glyphosate symptoms ranged from leaf yellowing and browning, to slight browning of interveinal leaf tissues. Acetochlor + atrazine, or metolachlor alone caused the abnormality referred to as “leaf tatters” where in severe cases, only the main veins are present with limited amounts of interveinal tissues. Detailed description of the injury symptoms, supplemented with photographs are posted on a web site: http://www.nres.uiuc.edu/research/herbicide_research/index.htm
Can Sunn Hemp Decrease Nitrogen Fertilizer Requirements of Vegetable Crops in the Southeastern United States?
Authors: Avila Laura , Scholberg Johannes , Roe Nancy , Cherr Corey
Published: February 2019

Increased dependency of conventional agriculture on inorganic fertilizers and fossil fuels may hamper long-term sustainability of agricultural production. Sunn hemp (Crotalaria juncea) was tested during summer in a Community Supported Agriculture vegetable crop operation located in Southeast Florida, from 2003 to 2005. Farm system components included sunn hemp (SH) vs. a conventional fallow during summer, tomato (Lycopersicon esculentus) and pepper (Capsicum annum) during winter and spring sweet corn (Zea mays). Tomato and pepper were fertilized with 0, 67, 133, 200 kg N/ha (2003) vs. 0,100, 200 kg N/ha (2004/05). Sweet corn received 133 or 200 kg N ha (2003) vs. 100 kg N/ha (2004/05). Average SH biomass was 3.7 Mg/ha. In 2003 tomato yields following SH without supplemental N were similar to fallow, with 200 kg N/ha. By the third year, tomato and pepper yields in SH plots were 25% and 26% higher, respectively. Conventional pepper amended with 200 kg N/ha had only 8% higher yields than treatments amended with 100 kg N ha and CC. Overall, sweet corn had low yields, but yields increased if the preceding tomato/pepper crop received higher N rates. In 2003, sweet corn fertilized with 200 kg N/ha following a SH-fall vegetable crop produced 17% higher marketable yields compared to the fallow treatment. During 2004 and 2005, sweet corn within the SH-non-fertilized tomato system produced 29% higher yields compared to a similar conventional system. Results show that, in this rotation, both fall vegetable crops and sweet corn yield benefit from residual N fertilizer. Mineralization of SH may thus not only benefit the immediately following crop, but its effects can be seen later during the year.
Citrus Bioactive Limonoid Extraction using Environment-friendly Hydrotropy
Authors: Dandekar Deepak , Jayaprakasha G. K. , Patil Bhimanagouda
Published: February 2019

Citrus consumption has been shown to promote human health due to presence of several bioactive compounds. In the process of understanding the health benefits of citrus, we need to isolate and characterize these compounds. Limonoids are one of such prominent, but lesser-known phytonutrients that have been shown to prevent cancers of the mouth, skin, lung, breast, and colon. With the growing interest in the health-promoting properties of citrus limonoids, the demand for these bioactives has significantly increased. It has been critical to explore environment-friendly extraction methods rather than using hazardous organic solvents. A water-based hydrotropic extraction of limonoid aglycones from sour orange (Citrus aurantium L.) seeds was developed. Two hydrotropes, sodium salicylate (Na-Sal) and sodium cumene sulfonate (Na-CuS), were studied for extraction efficiency using the Box Behnken experiment design method. The extraction efficiency of prominent aglycone limonin was observed depending on hydrotrope concentration, extraction temperature, and percentage of raw material loading. Response Surface Analysis (RSA) of data predicted the optimum conditions for maximum yield. Recovery of aglycones from filtered extract is also easily achieved by mere dilution using water at pH 3 or 7 or by partitioning the extract with dichloromethane. At optimum conditions, limonin yield of 0.46 mg/g seeds in the case of Na-Sal extraction and 0.65 mg/g seeds in the case of Na-CuS extraction was achieved. The results demonstrated that the hydrotropic extraction process of limonoid aglycones has practical commercial importance. This project is based upon work supported by the USDA–CSREES IFAFS #2001 52102 02294 and USDA–CSREES #2005-34402-14401 “Designing Foods for Health” through the Vegetable and Fruit Improvement Center.
(1) Influence of Storage Temperature and Time in Storage on Pigment Content of Potato (Solanum tuberosum L.)
Authors: Alenazi Mekhled M. , Hughes Harrison G. , Stushnoff Cecil , Holm David G.
Published: February 2019

The influence of storage temperature and length of time in storage on anthocyanin tuber concentration were investigated in seven potato genotypes. These genotypes were cultivars `All Blue' and `Yukon Gold' plus five selections that were various skin/flesh color types of red/red, purple/purple, white/yellow, and two red/yellow types. The red, blue, and purple colors are the result of various anthocyanin compounds. Tubers of the seven genotypes were stored at 4.4 or 10 °C for 0, 4, 6, 8, 10, 12, 16, 20, or 24 weeks. Both fresh and freeze-dried samples of the tubers were evaluated for each temperature and time treatment combination. Extractable anthocyanins were found in only the three pigmented genotypes red/red, purple/purple, and `All Blue'. Anthocyanin concentrations were estimated spectrophotometrically with a Molecular Devices Spectramax 384, based upon extinction coefficients reported in the literature for purple and red pigmented potatoes. Anthocyanin concentration increased in storage as time in storage increased for both fresh and freeze-dried samples. Tubers stored at the cooler temperature (4.4 °C) had higher levels of anthocyanin than those tubers stored at the higher temperature (10 °C). Increased levels of anthocyanins in cold-stored tubers may be linked to the conversion of starch to sugar (so called cold sweetening) known to occur at cold storage temperatures. Pigment extraction was more efficient from freeze-dried tuber samples compared to fresh tuber samples. There was, however, a similar increasing trend in both freeze-dried and fresh tuber sources with storage duration.
(85) Determination of D-Glucarate Content in Grapefruit Varieties
Authors: Perez Jose L. , Jayaprakasha G.K. , Patil Bhimanagouda S.
Published: February 2019

Grapefruit has potential health-promoting properties due to the presence of multitude bioactive compounds. Ongoing cell culture and animal studies in our lab using limonoids and flavonoids have provided strong evidence of their protective properties for preventing chronic diseases. Studies related to D-glucarate, a natural, nontoxic bioactive compound found in grapefruit, has not been explored. One of the derivatives, such as D-glucaro-1,4-lactone, is reported to be a potent ß-glucuronidase inhibitor. With the inhibition of ß-glucuronidase enzyme, glucuronidation will be favored. Glucuronidation is a conjugation process through which potentially carcinogenic environmental toxins can be neutralized. In this context, quantification of glucarate using HPLC was developed. Samples from grapefruits were prepared by heating fruit extract with distilled water. Further, the extract was homogenized and centrifuged. The supernatant was treated with petroleum ether to remove non-polar substances. Then the extract was subject to ion exchange chromatography. Fractions were collected and analyzed by analytical HPLC for the quantification of D-glucarate content and its lactone. This project was supported by the USDA-CSREES grant for Designing Foods for Health through the Vegetable and Fruit Improvement Center.
(89) Abiotic Factors Possibly Contributing to Reset Failure of Citrus Trees in a Commercial Grove in Florida
Authors: Albano Joseph , Sahi Shivendra , Wilson Chris , Bowman Kim
Published: February 2019

Reset/replant problems and/or failure are recognized as a problem in fruit tree production throughout the world. Problems in establishing or reestablishing fruit trees have been documented in apple, peach, grape, and citrus. Research to date has not identified a single casual agent responsible for reset failure, but rather there is evidence that such problems are related to a complex interaction of biotic and abiotic factors. In this study, we compared abiotic factors related to soil texture and soil nutrients in healthy and reset failure areas of a commercial citrus grove in Florida. A significant difference in soil texture was found in healthy sand, silt, and clay (94%, 4%, and 2%, respectively) vs. failed (99% sand and <1% silt and clay) reset areas in the citrus grove block. Mehlich III extractions were performed on soil samples and levels of Ca, Cu, Fe, K, Mg, Mn, P, and Zn in the extract solution were significantly higher in healthy compared to failed reset areas of the citrus grove block. These data are consistent with what has been observed in other fruit crops where soil texture, which directly relates to soil hydrologic conditions, and soil nutrient levels have been identified as contributing factors related reset/replant failure in fruit tree crops.
(300) Safety and Productivity of Cool-season Salad Greens Grown in Soils Amended with Composts
Authors: Marsh Lurline , Cotton Corrie , Philip Elizabeth , Parveen Salina , Hashem Fawzy
Published: February 2019

Excessive amounts of poultry waste on the Delmarva Peninsula of the United States, coupled with the availability of yard waste, may be potential inexpensive nutrient sources for growing vegetables. However, these composts may contain unsafe microorganisms. This study, therefore, was conducted to determine the presence and persistence of biological agents in soil treated with poultry compost and yard waste. Tatsoi [Brassica rapa (Narinosa Group)] and spinach (Spinacia oleracea L. `F415' and `Seven R') were planted under a high tunnel to extend their fall growing season. Samples of soil–compost mixture and original poultry compost were collected once a month for 4 months. Escherichia coli O157:H7 in the samples was determined by enrichment and immunomagnetic separation, and was not detected in any of the soil-mixtures. However, this bacterium was detected in the original poultry compost in very low numbers. Plant leaves were harvested periodically. Results showed that tatsoi plants significantly produced larger leaves and higher fresh weight in soils amended with organic compost with the tendency for yield to increase with the increase in harvest date. Generally, the organic amendments did not influence size and total fresh weight of spinach leaves, although earlier harvests tended to produce significantly larger leaves and higher fresh weight.
(225) Effects of Nutrient Salt Formulations and PGRs on Axillary Shoot Proliferation of Tropical Hibiscus
Authors: Scoville Rebecca E. , West Todd P.
Published: February 2019

The objective of this study was to investigate the effects of multiple nutrient salt formulations and different plant growth regulator concentrations on initiation and proliferation of axillary shoot culture of tropical hibiscus (Hibiscus rosa-sinensis L.). Combinations of five thidiazuron (TDZ) concentrations (0, 10-6, 10-7, 10-8, or 10-9 M) in conjunction with two 6-benzylaminopurine (BA) concentrations (0, 10-5 M) and two indole-3-butryic acid (IBA) concentrations (0, 10-5 M) were compared to determine which plant growth regulator combination(s) would stimulate the proliferation of the most viable axillary shoots. Also, five nutrient salt formulations (MS, 1/2 MS; Macro MS, WPM, LP, or DKW) ranging from high to low salt formulations were studied to determine a suitable nutrient medium formulation for axillary shoot proliferation. Nodal explants that were 2 cm in length were used to initiate cultures and were maintained on the various medium treatments plus 30 g·L-1 sucrose and 7 g·L-1 agar at a pH of 5.8. Explants were incubated about 30 cm beneath cool-white fluorescent lamps that provide a photon flux of about 40 μM·m-2·s-1 for a 16-hour photoperiod at 25 ± 3 °C. Nodal explants were transferred every 3 weeks for a total culture period of 12 weeks. At each transfer date data were collected on node number, axillary shoot number and length. Initial results indicate that high nutrient salt formulations coupled with low TDZ concentrations performed better at axillary shoot initiation. Poor shoot elongation was observed and further research needs to be performed to address this issue.
(92) Preplant Practices to Manage Armillaria Root Rot Disease and Other Soil Pathogens on a Commercial Peach Replant Site
Authors: Layne Desmond R. , Schnabel Guido
Published: February 2019

In 2003, a replicated long-term research trial was established on a commercial peach replant site with a history of Armillaria root rot and other soilborne diseases. The objectives of the trial were to determine the short- and long-term effects of preplant fumigation, rootstock, and preplant root dipping with mycorrhizal fungi and beneficial bacteria on tree growth, productivity, and survival. Preplant fumigants included none (control), methyl bromide, Telone II, or Enzone. Rootstocks tested included Guardian, Lovell, and Halford. Root dipping (or not) was with MycorTree. The scion cultivar was Big Red. There were a total of 24 experimental treatment combinations and the trial site comprised more than 1500 trees on 11.5 acres. By 2 years after planting, fumigation with Enzone was disadvantageous when compared with no treatment at all. Enzone-treated blocks had higher tree mortality or were significantly reduced in growth compared to other treatments. Preplant fumigation with Telone II or methyl bromide, however, resulted in reduced tree stunting and phytotoxicity and increased tree growth when compared to the untreated control. After 2 years, 10% of the total trees planted were dead. Half of these were from the Enzone treatment. Enzone does not appear to be a viable preplant fumigation product for South Carolina peach growers, based on this preliminary data. Both Guardian and Halford rootstocks had performance superior to Lovell during the first 2 years. Although Guardian trees were smaller than Halford at the time of planting, by the end of the second growing season, their TCA was not significantly different. There was no benefit to preplant root dipping with MycorTree. Experimental results were not influenced by the location of trees on the site.
(105) Variation in Cornelian Cherry Phytonutrient Capacity
Authors: Ozgen Mustafa , Tulio Artemio Z. , Chanon Ann M. , Janakiraman Nithya , Reese R. Neil , Miller A. Raymond , Scheerens Joseph C.
Published: February 2019

To investigate the variation in the phytonutrients of Cornelian cherry (Cornus mas L.), fruit was harvested at the blush (S1), red (S2), and ripe (S3) stages from five genotypes maintained at the Secrest Arboretum, Wooster, Ohio. The S1-S3 samples were characterized for color reflectance and then frozen at –28 °C. After storage, samples were analyzed for dry weight (DW), total soluble solids (TSS), sugars (FRU + GLU), organic acids (ORG), total phenols (PHE), total anthocyanins (ACY), individual anthocyanins (IA), hydroyzable tannins (HT), and antioxidant capacity (FRAP and ABTS). From S1 to S3, DW and TSS increased by 24% and 21%, respectively, and L, hue angle, and chroma values decreased. On a DW basis, all analytical parameters were significantly influenced by genotype and stage. The ACY levels rose 7-fold during ripening, but PHE contents declined by 10%. In ripe fruit, HT comprised the bulk of the PHE constituents, whereas ACY accounted for only 7.6% of PHE levels. Variability among genotypes was moderate for all ripe fruit parameters but ACY. Ripe fruit varied little in color parameters and ACY (fwb) and IA (fwb) were not significantly different among cultivars. The Cy 3-gal and pel 3-gal levels were negatively correlated. Antioxidant capacity declined 16% to 18% during ripening. Ripe fruit FRAP and ABTS values were higher than those reported for most fruits, averaging 596 ± 85 and 629 ± 85 μmol TE eq./gDW, respectively. ABTS and FRAP values were highly correlated with each other and with PHE and HT contents, but were loosely and negatively related to ACY levels. Considering our limited sample size, we concluded that the phytonutrient capacity of cornelian cherry is substantial, predominantly associated with tannins and moderately variable among genotypes.