bluuebunny/crossref_metadata_2025 huggingface dataset:
Net Photosynthetic and Evapotranspiration Rates in Situ of Tomato and Lettuce Plug Sheets in the Greenhouse
Authors: Shibuya Toshio , Kitaya Yoshiaki , Kozai Toyoki , Nakahara Masaichi
Published: February 2019

Net photosynthetic and evapotranspiration rates of tomato (LAI = 2.3) and lettuce (LAI = 6.6) plug sheets were estimated based on measurements of the weight of plug sheets and vertical profiles of CO2 concentration above the plug sheets. The measurements were continued in situ for several days in a greenhouse when plugs were at transplant stage. The maximum net photosynthetic rates of tomato and lettuce plug sheets were 0.8 and 2.0 mg CO2/m2 per sec on a plug sheet area basis, respectively. The maximum evapotranspiration rates of those sheets were 100 mg·m–2·s–1. Net photosynthetic and evapotranspiration rates of tomato and lettuce plug sheets increased linearly with an increase in solar radiation flux, with a correlation coefficient of 0.9.
Timing of Transplanting Affects Survival of Prairie Perennial Forb Seedlings
Authors: Kemery Ricky D. , Dana Michael N.
Published: February 2019

Seedlings of six species of native prairie perennial forbs were installed monthly from Oct. 1993 to Nov. 1994 on two highway sites near West Lafayette, Ind. Survival varied significantly among species. Overall, 85% of Aster novae-angliae seedlings survived compared to 15% survival of Liatris pycnostachya seedlings. Survival also varied significantly with time of installation. Three species (Aster novae-angliae, Ratibida pinnata, and Veronicastrum virginicum) exhibited 95% survival when planted in mid-October, compared to 50% survival when planted in March. Fifty-seven percent survival of Echinacea pallida seedlings was observed with April plantings, compared to 9% survival of September plantings. Results of this study indicate that transplant survival rates of particular prairie species may be enhanced by precise timing of planting in late fall or early spring.
Adventitious Regeneration Studies in Hibiscus Species
Authors: Reichert Nancy A. , Oakley Nathan R. , Baldwin Brian S.
Published: February 2019

An adventitious regeneration protocol developed for Hibiscus cannabinus L. (kenaf) was attempted on various ornamental hibiscus species. Hibiscus syriacus (Althea, Rose of Sharon) has been successfully regenerated using the kenaf protocol. Leaf tissue from two cultivars (`Double Pink' and `Diana'—a triploid) was placed on kenaf regeneration media. Adventitious shoots emerged from both cultivars within 8 to 10 weeks. Shoots were then excised and placed on a medium for rooting. Additional hibiscus species have been evaluated for regeneration ability. Previous studies with kenaf determined the adventitious regeneration protocol could induce mutations (somaclonal variation) in the regenerants. Variations in kenaf stem color and flower shape were noted. Since many ornamental hibiscus are asexually propagated, once a desired mutant is identified, it could be maintained and propagated without loss of the unique trait(s).
Scanning Electron Microscope Studies of the Development from Germination to Mature Plant of Some Hardy Terrestrial Orchids
Authors: Szendrák Erika , Read Paul E. , Eszéki Eszter R. , Jámbor-Benczúi Elizabeth , Csillag Aniko
Published: February 2019

Cultures of several orchid species [Barlia robertiana (Loisel.), Dactylorhiza fúchsii Soó, D. incarnata (L.) Soó, D. maculata (L.) Soó, D. majalis (Rchb.), D. saccifera (Brong) Soó, D. sambucina (L.) Soó, Gymnadenia conopsea (L.) R.Br., Himantoglossurn hircinum (L.) Spreng., Ophris sphegodes Mill., Orchis coriophora ssp. fragrans L., Orchis laxiflora ssp. palustris Lam., Orchis mascula L., Orchis morio L., Platanthera bifolia (L.) Rich., Spiranthes aestivalis (Poir.) Rich.] were initiated with fresh ripe seeds from desiccated fruit and 4-month-old in vitro seedlings. The medium used for both germination and seedling culture was a modified FAST medium. Samples for the scanning electron microscope (SEM) surveys were taken from the in vitro cultures and some plant materials were collected from their native habit. Samples were observed with a Tesla BS 300 SEM. Seeds ranged from 300 to 450 μm in length and were flask-shaped. The first germination step is opening of the seedcoat, when the first few white cells will be visible. After a few weeks, the apical meristem appears. The young protocorm is covered with numerous translucent rhizoids. In the last stage of germination, the first root and the first true leaf start to develop. After 2 years, they are suitable for transfer ex vitro. Structure of the mature organs and tissues can be examined at this stage.
A Comparative Study on Plant Regeneration from Protoplasts of Two Genotypes of Asparagus officinalis L.
Authors: Mukhopadhyay Sandip , Desjardins Yves
Published: February 2019

The effects of culture media, culture modes, and carbon sources on plating efficiencies of protoplasts of two genotypes of Asparagus officinalis L. were investigated. Protoplasts grew best in a semisolid culture system containing half-strength MS medium with 1 mg NAA/liter, 0.5 mg zeatin/liter, 0.6 M glucose, and 0.1% Gelrite. The plating efficiencies were 12.5% and 8.1% for genotypes G 203 and G 171, respectively. Embryogenic calli were produced from protoplast-derived microcalli after culturing on MS medium with 1 mg 2,4-D, 3% sucrose, and 0.2% Gelrite. The somatic embryos were initiated, matured, and then germinated to plantlets in MS medium containing 0.1 mg NAA/liter, 0.3 mg 2-iP/liter (EMM), and different levels of carbohydrates. Transfer of somatic embryos from EMM with 10% glucose to EMM containing 2% sucrose produced the highest number of bipolar embryos and plantlets. The plantlets regenerated shoots and roots in MS medium with 3% sucrose, 0.1 mg NAA/liter, 0.1 mg kinetin/liter, and 1.28 mg ancymidol/liter. Cytological analysis of these plants revealed 2n = 20 chromosomes.
Influence of Boron and Salt Concentration on Calcium-45 Uptake by Micropropagated Potato Plantlets
Authors: Abdulnour Jihad , Donnelly Danielle , Barthakur Nayana N.
Published: February 2019

Calcium45 uptake by in vitro-grown `Bintje' potato plantlets increased linearly as the salt concentration of the nutrient medium was decreased from 2 to 0.5 MS. The increase in Ca45 absorption was significant for shoot tips and stems (P ≤ 0.05), but not for foliage. In shoot tips and stems, Ca45 uptake increased linearly as medium Ca increased, independent of boron (B) medium concentrations. However, in leaves, this increase was linear at low B concentrations (0.05 mM) and parabolic at relatively higher B concentrations (0.1 and 0.2 mM). When medium Ca was 9 mM, Ca45 absorption was reduced significantly (P ≤ 0.01) by increasing B concentration in the medium.
Long-term in Vitro Regeneration of Hamelia patens
Authors: Sankhla D. , Davis T.D. , Sankhla N. , Upadhyaya A.
Published: February 2019

This report describes an efficient in vitro regeneration protocol for H. patens (firebush), a heat-tolerant ornamental shrub native to tropical and subtropical America. Shoot cultures were initially established using shoot tips placed on MS-revised medium containing 2.3 μM 2,4-D, 2.3 μM kinetin, and 0.25% polyvinylpyrrolidone. Other types of explants (nodal and internodal segments, leaf pieces, floral buds) did not regenerate shoots when placed on this medium. Two-month-old plantlets derived from the shoot tips were subcultured on MS medium supplemented with 0.5 μM thidiazuron (TDZ), and within 3 to 4 weeks, some callus was produced at the root–shoot junction. When this callus, with a small portion of the root and shoots, was placed on MS medium with 0.05 μM TDZ and 0.01 μM ABA, prolific shoot formation occurred within 3 to 4 weeks followed by root formation. By regular subculturing every 5 to 6 weeks, hundreds of plantlets have been obtained over the past 3 years with no apparent decline in regeneration potential. Addition of activated charcoal (0.5%) to the culture medium has greatly improved growth of the plantlets.
The Effects of Some Antioxidants on the Growth of Excised Date Palm (Phoenix dactylifera L.) Roots Cultured in Vitro
Authors: Dlaigan Yousef I. , Said A.E. , El-Hamady M.A.
Published: February 2019

The objective of this investigation was to study the effects of some antioxidants on the growth and elongation of in vitro-cultured date palm roots. Several trials were conducted to determine the antioxidant and the concentration of antioxidants used in date palm tissue culture. Three types of antioxidants were tested—activated charcoal, polyvinylpyrrolidone (PVP), and sodium metabisulfite (NA2S2O5)—in various concentrations, singly, or in combinations. The medium used for root culture consisted of MS salts mixture, 1/2 modified White's organics, 60% sucrose, 0.004% inositol, 240 mg adenine sulfate/liter, 1.0 mg 2,4-D/liter, and 2.0 mg kinetin/liter. pH was adjusted at 5.7 ± 0.1. Concentrations of activated charcoal tested (in g–liter–1) were: 0.0, 1, 2, 3, 4, 6, 8, 10, and those of PVP (in g–liter–1) were: 0.0, 5, 10, 20, 40 (with or without 4 g activated charcoal/liter). NA2S2O5 concentrations (in mM) tested were: 0.0, 0.2, 0.4, 0.8, 1.6 (with 4 g activated charcoal/liter). The addition of activated charcoal to the culture medium of date palm roots is of vital importance. Four grams per liter gave the best growth and elongation, and there was no significant difference between it and 10 g–liter–1. No growth or elongation occurred in the control. PVP, however, significantly inhibited growth and elongation of cultured roots at all concentrations tested. NA2S2O5, however, stimulated growth and elongation at 0.2 mM. Higher concentrations inhibited growth and elongation.
Genetic Diversity in Muscadine and Bunch Grapes Based on RAPD Analysis
Authors: Lu Jiang , Qu Xianping , Lamikanra Olusola
Published: February 2019

Two morphologically very distinct grapevines belonging to the subgenera Euvitis and Muscadinia of the genus Vitis are cultivated in the United States. The former is commonly called “bunch” grape, while the latter is usually called “muscadine.” Genetic diversity among these grapes was investigated based on random amplified polymorphic DNAs (RAPDs). Sixteen grape cultivars, with their parentage including V. rotundifolia, V. vinifera, and several American Vitis species, were used for the RAPD analysis. More than 200 RAPDs were produced from 20 random primers. More than 90% of which were polymorphic between the muscadine and the bunch grapes, while polymorphism was considerably low within the muscadine and the bunch grapes. The relationships of grapes between these two subgenera were estimated based on bandsharing and cluster analysis. The result based on the DNA analysis agrees with the isozyme data obtained from a separate study, which demonstrated that the muscadine grape shares very low common alleles with the American bunch grapes and the European grapes.
Pest and Disease Control for Vesicular–Arbuscular Mycorrhiza (VAM) Pot-grown Plants
Authors: Parent Susan , Duval Annie
Published: February 2019

Increased use of VAM for pot-grown cultures has sustained certain inquiries as to the compatibility of pesticides and biocontrol agents with this novel practice. Asparagus, Boston fern, geranium, and poinsettia were cultivated in a peat-based medium (SB-Mix) with various fungicides, insecticides, and insect predators. Each plant consisted of an individual trial. All treatments were randomly set up in a complete block experimental design consisting of a noninoculated control and pre-inoculated with Glomus intraradices, in combination with the different pesticides used for a given plant species. Commonly used pesticides in greenhouses were chosen, and the concentration applied was as recommended by the manufacturer. A control, consisting of water, was included with the pesticides tested. The effect of a given pesticide varied from one plant species to another concerning root colonization by the VAM and plant growth. The poinsettia growth results were significantly superior with the water-treated plants than with those that received insecticidal soap, dienochlor, and dicofol on a regular basis. Colonization rates, however, were low with all treatments, but significantly lower with oxine benzoate. Growth parameters and colonization rates of geranium, Boston fern, and asparagus showed no significant differences between water and pesticide treatments, even those treated with benomyl, which has been reported in the past to reduce colonization rates. These results show that a good pesticide and insect predator integration control program will not alter the VAM colonization rates.
Transfer of Lycopersicon chilense Chitinase Gene to Cultivated Tomato (L. esculentum)
Authors: Agharbaoui Zahra , Yu Long Xi , Poysa Viano , Tabaeizadeh Zohreh
Published: February 2019

We have isolated a drought-induced chitinase gene from L. chilense, a wild tomato species. Owing to our interests in genetic improvement of cultivated tomato, we have transferred the L. chilense chitinase gene to this species. The transformation plasmid constructed contained the coding sequence of L. chilense chitinase gene linked to CaMVS35 promoter as well as the NPT II gene linked to nopaline synthetase promoter. The leaf disk transformation regeneration technique was applied to one commercial tomato cultivar and four inbred lines. Shoots were produced on the selection medium through direct or indirect organogenesis. Plantlets that have been rooted on kanamycin-containing medium were transferred to soil where they grew to maturity and produced flowers and fruit. The transgenic nature of some of the analyzed plants was confirmed by polymerase chain reaction. Research is continuing to evaluate transgenic plants with regard to their level of tolerance to phytogenic fungi.
Heavy Metals in Fruit and Berries in Kaunas District (Central Lithuania)
Authors: Svagzdys Stanislovas
Published: February 2019

During the expeditions of 1989–92, samples of soil, fruit, and berries were picked up in Kaunas District (central Lithuania) and experimental orchards to determine the content of heavy metals (Cr, Pb, Ni, Zn). They were established by the atomic absorption meter AAS-30. Within in the limits of the industrial center (Kaunas), the content of heavy metals in soil exceeds the background: cadmium, 6 times; lead, 3, 6 times; zinc, 5 times. When fruit trees grow within the city limits, chromium and lead accumulates in the fruit skin and pith. There is probability that increased amounts of heavy metals can accumulate in the flesh. Fruit grown by roads with intensive traffic, as in town zones, accumulate chromium in the pith and lead in the skin. Fruit from trees grown at a distance of 50 to 100 m from the road contained high amounts of chromium and lead in the pith. In all investigated cases, nickel and zinc accumulated in the pith. When fruit trees grow by roads with intensive traffic or within city limits, fruit are contaminated more with chromium than with lead. Consumers should use only the flesh and remove the skin and pith of such fruit. In experimental orchards, different crops accumulated different amounts of diverse heavy metals. In an irrigated area, strawberries accumulated more heavy metals than currants. Heavy metals (Cr, Pb, Ni, Zn) were found in small quantities in the flesh of sour cherries and plums. Microfertilizers (0.1% boric acid applied after flowering) reduced the absorption of heavy metals (especially Cr and Pb) to the plant's reproductive organs.
Foliar Spray at Spring Flush Enhances Zinc Status of Pistachio and Walnut Trees
Authors: Zhang Qinglong , Brown Patrick H.
Published: February 2019

In this study, we investigated the effectiveness of several Zn formulations applied at various times of the year in increasing Zn status of pistachio and walnut leaves. Formulations included inorganic and organic forms of Zn. Fall sprays was ineffective at supplying Zn to developing leaves even when very high rates (5000 ppm) were used. Late dormant and budbreak sprays were effective at supplying Zn to developing leaves and nuts only when extremely high rates (5000 ppm) were applied. Spring flush sprays were the most effective, while late spring and summer sprays were ineffective. The majority of the Zn applied remained in the epidermis of the sprayed leaves, which resulted in high Zn content of leaves but poor correction of Zn deficiency and little or no translocation of Zn to other plant parts. Many of the Zn formulations sprayed at spring flush at a rate of 1000 ppm effectively increased leaf Zn values by at least 10 μg–g–1. Addition of an appropriate organic acid to the spray solution and adjustment of pH to ≈4.5 improves leaf uptake and translocation of Zn. Addition of specific surfactants into the spray solution is also recommended. Use of N- and P-containing Zn spray formulations is less effective than sulfur-based sprays (i.e., ZnSO4). Significantly, there is little residual effect of foliar sprays (even at spring flush), indicating that consecutive sprays for several years are needed to maintain productivity in Zn-deficient regions.
Fruit Tree Light Interception, Simulated Carbon Assimilation, and Carbon Partitioning
Authors: Grossman Yaffa L. , DeJong Theodore M.
Published: February 2019

Plant dry matter production is proportional to light interception, but fruit production does not always increase with increased light interception. Seasonal daily patterns of light interception by cling peach trees planted in four different planting density/training systems were obtained using a Decagon ceptometer. The High Density V system (1196 trees/ha) intercepted significantly more light than the KAC V and Cordon systems (918 trees/ha). The Vase system (299 trees/ha) intercepted significantly less light than the other systems. Response surfaces using a quadratic model with interactions for time of day and day of year explained 84% to 91% of the variance in the data sets for each training system. Crop yields per acre were greatest for the High Density V, followed by KAC V, Cordon, and Vase, corresponding to the light interception data. A carbon budget model, which incorporated canopy photosynthesis, respiration, and carbon partitioning based on organ growth potentials, was used to simulate seasonal patterns of carbon assimilation, crop dry weights, and individual fruit dry weights.
Gas Exchange Responses of Papaya Leaves to Light Variation as Influenced by Drought
Authors: Clemente Hiphil S. , Marler Thomas E.
Published: February 2019

Container-grown papaya plants were subjected to a slow drying cycle by replenishing a portion of the mean daily water loss. When light-saturated net CO2 assimilation (A) of stressed plants was ≈70% of well-watered plants, sun–cloud transitions were simulated by placing shadecloth between a lamp and the leaf cuvette. The cuvette was initially positioned to receive photosynthetic photon flux (PPF) of ≈1600 μmol–m–2–s–1. The shadecloth was placed over the cuvette for a 3-min period (250 μmol–m–2–s–1), then removed. Gas-exchange responses were recorded for another 3 min of high light. Within 20 sec of initiating low light on well-watered plants, A was <50% of the high-light value. Stomatal conductance (gs) of these plants began to decline by 60 sec and slowly declined to <90% of the high-light value. Both A and gs recovered to the original values by ≈2 min following return to the high-light conditions. For stressed plants, the decline of gs under low light began earlier and was of greater magnitude, and gs and A recovery following the return to high light was delayed. These results indicate that papaya has suntracking capabilities, and mild drought stress enhances the tracking response.
Early Growth Model of Muskmelon (Cucumis melo L. cv. Hiline) Using Accumulative Windspeed Frequency
Authors: Daningsih Entin , Hodges Laurie , Brandle James R.
Published: February 2019

Experiments were conducted during summer seasons from 1991 to 1994 to find out the effect of winds on early growth of muskmelon. A randomized complete-block design with sheltered and exposed areas as treatments was used. Sensors for air temperature and relative humidity (model HMP35C or model XN217, Campbell Scientific) were placed at canopy height and 3-cup anemometers (model 12102, R.M. Young, Traverse City, Mich.) were 50 cm aboveground. All sensors were connected to CR10 automatic data loggers and recorded hourly average data. Using regression analysis, we found that the accumulative windspeed frequency below threshold (<4 m–s–1) can be used to predict both accumulative hourly heat units of air temperature (GDHT) with R2's more than 0.85 and total muskmelon fresh and dry weight and leaf area index at early growth. Predicted models using accumulative hourly windspeed frequency have R2's >0.80 in sheltered areas. Adding vapor pressure deficit to the model improves the prediction of muskmelon early growth, especially in exposed areas.
Effects of Supplementary Lighting on Growth and Primary Nitrogen Metabolism of Greenhouse Lamb's Lettuce and Spinach.
Authors: Chadjaa Hassan , Vézina Louis-Phillipe , Dubé Sylvain , Gosselin André
Published: February 2019

Two cultivars of lamb's lettuce (Valerianella sp L. cvs. Valgros et Vit) and one cultivar of spinach (Spinacea oleracea L. cv. Martine RZ Fl) were subjected to supplemental lighting treatments provided by high-pressure sodium lamps (HPS, PL 90, P.L. Lighting Systems). The PAR level was 50 μmol– m–2· s–1. Seedlings were subjected to three photoperiods (natural, 12, and 16 h). The experiment was conducted from Jan. until Apr. 1994. The fresh weight of plants grown under supplemental light was higher than plants grown under natural light. Nitrate concentration was lower in the leaves of plants grown under supplemental light while nitrate reductase activity (NRA) was increased. The cultivar Valgros was more productive than Vit, but accumulated more nitrates. At harvest, the fresh weight of Valgros plants grown under 12- and 16-h photoperiods were 30% and 50% higher, respectively, than those grown under natural photoperiod. The fresh weight of Vit grown under 16 h of supplemental light was 30% higher than under natural photoperiod. The lowest nitrate concentrations in plants were obtained under a 16-h photoperiod and the highest NRA were obtained with the same treatment. Compared to that obtained under natural photoperiod, the fresh weight of spinach shoots was 40% higher when seedlings were lighted for 12 h and almost 100% under 16 h. The lowest nitrate accumulation in spinach was found for plants grown under 16 h supplemental lighting.
Development of Micropipette Method for Collecting Vacuolar Contents from Intact Tannin Cells in Persimmon (Diospyros kaki) Fruit and Preliminary Analysis of its Constituents
Authors: Yonemori K. , Oshida M. , Sugiura A.
Published: February 2019

In order to study the nature of tannins in vivo, we developed a method for collecting the vacuolar contents from intact tannin cells in persimmon fruit. We used a micropipette controlled with a MMS-77 micromanipulator system (Shimadzu Co., Kyoto, Japan) under an inverted microscope. Fruit flesh of mature persimmon fruit (cv. Miyazakimukaku) was cut into 300-μm-thick sections with a DSK-100 miaoslicer (Dosaka EM, Kyoto, Japan). The sections were then put on a glass slide, and a micropipette was inserted into a tannin cell to withdraw its contents. After determination of the sap volume collected, the sample was injected into a 25-μl drop of water on a glass slide. Then, the water-drop containing the tannin sample was transferred to a small microfuge tube and stored in a freezer until analysis. Based on calculations, we could collect approximately 7 to 12 nl of vacuolar contents per tannin cell. When tannin and sugar contents per tannin cell were determined, we found that tannin cells contain tannins at 10% to 15% as catechin equivalents (w/v) and 8% to 10% total sugars (w/v), while a whole fruit contains tannins at 1% to 1.5% as catechin equivalents and 10% to 13% total sugars on fresh weight basis. We are currently continuing more detailed analysis of tannin cell constituents.
Effects of Selected Fungicides on Pollen Germination, Tube Growth, and Distribution of the Cytoskeleton in Tradescantia virginiana
Authors: He Yi , Wetzstein Hazel Y. , Palevitz Barrv A.
Published: February 2019

Fungicides have been shown to negatively affect pollen germination, tube growth, and fruit set in important crops. However, little is known regarding possible modes of action in higher plant cells. To address this, the effects of propiconazole or benomyl on pollen germination and tube growth were evaluated in Tradescantia virginiana using light microscopy and immunocytochemistry. Concentrations were selected at levels that had inhibitory effects, but did not totally arrest germination and tube elongation, i.e., propiconazole and benomyl were added at 0, 102, 136, or 170 μl·liter–1, and 0, 480, 600, or 720 mg·liter–1, respectively. Both fungicides inhibited germination, cytoplasmic streaming, tube elongation, and induced abnormal tube morphology and cytoskeletal distribution. Propiconazole-treated tubes had weaker microfilament signals, with amorphous staining. Microtubule (Mt) distribution was severely affected. In benomyl-treated tubes, Mts were fewer in number, fragmented, sinuous, and increasingly disorganized. Possible mechanism(s) will be discussed.
Proteins Associated with Germination of Cucumber at Various Temperatures
Authors: Russo V.M. , Biles C.
Published: February 2019

Cucumber (Cucumis sativus L.) seed require soil temperature to be around 20C for efficient germination. This hinders early planting in cool soils. This study was conducted to determine how germinating seed of cucumber cultivars Earlipik 14 and Arkansas Little Leaf at 13.9, 15.6, and 20C in the dark affected protein formation. Seed were removed from moist chambers at 0, 12, 24, 48, 72, 84, 96, 120, and 168 h. Germination, defined as the radicle being at least 5 mm long, was determined at each time. Germinated and ungerminated seed was prepared for polyacrylamide gel electrophoresis. At 20C, 90% to 100% of seed had germinated by 48 h. At 15.6C, 20% to 50% of seed germinated by 168 h, and at 13.9C, ≈2% of seed had germinated by 168 h. For seed incubated at 20C, concentrations of proteins at 70.1 kDa decreased, while those at 37.4, 43.4, and 50 kDa increased after 24 h, which corresponded to formation and elongation of the majority of radicles. These changes were expressed later for seed germinated at 15.6 and 13.9C. Identification of the proteins is being attempted. The importance of these proteins in germination and early development will be discussed.
Nuclear Magnetic Resonance for Monitoring Carbon Metabolism in Sweet Corn
Authors: Russo Vincent M. , Wright John
Published: February 2019

Understanding carbon metabolism can provide insight into physiological processes regulating yield, senescence, and resistance to pathogens in sweet corn (Zea mays L.). This study was conducted to determine if nuclear magnetic resonance (NMR) spectroscopy could be used to monitor changes in carbon metabolism at various growth stages in the shrunken-2 sweet corn cultivar Illini Gold. The 7th, 9th, and 11th stalk internodes were excised at midwhorl (V9), tassel emergence, 50% silking, and fresh-market harvest stages. The rind was removed and the sap expressed. Carbon-NMR spectroscopy was conducted with a 200.7 MHz machine on the expressed sap. From V9 through 50% silking, peaks in spectra were uniformly grouped from ≈61 to ≈104 ppm. At fresh-market stage, additional peaks were found in the spectra at ≈17 to ≈20 ppm, with the majority of peaks found from ≈57 to ≈104 ppm. The biological importance of these changes in carbon metabolism in sweet corn are not clear. Efforts are under way to identify the carbon-based compounds associated with the peaks.
Reduced Atmosphere Storage of Chinese Chestnuts
Authors: Smith Durward , Norton Joseph D.
Published: February 2019

Stored Chinese chestnuts (Castanea molissima Blume) are extremely susceptible to spoilage by molds. This research was initiated to determine if storage at reduced atmospheres in conjunction with vacuum-infused mycostatic chemicals could reduce mold growth and enhance the quality of stored nuts. Nuts were treated with two levels of buffered sodium propionate and two levels of buffered sodium benzoate and stored either at atmospheric pressure or at 0.17 atmosphere (4.0% O2) and minimal gas circulation. Relative humidity was maintained at 88%. Mold counts, weight, texture, and moisture content were recorded every 20 days. Mold counts of the chemically treated nuts stored at atmospheric pressure did not differ from untreated nuts. Storage at reduced atmosphere in conjunction with chemical treatment inhibited mold growth, reduced weight loss, and preserved fresh quality and viability of the nuts.
Expedition for Cucurbit Germplasm Exchange with China
Authors: Wehner Todd C. , McCreight James D. , Rhodes Bill B. , Zhang Xingping
Published: February 2019

Cucumber (Cucumis sativus L.), melon (Cucumis melo L.), watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai], and luffa (Luffa aegyptiaca Mill) accessions were exchanged between scientists of the United States and the People's Republic of China. Exchanges were made during a July 1994 visit of cucurbit research institutions in Shanghai, ZhengZhou, Yangling, Urumqi, Turpan, ChiangJi City, Tianjin, and Beijing. The trip was coordinated by the Office of International Cooperation and Development, USDA. Chinese scientists received elite American accessions with useful traits, and the American scientists received classic accessions that will be preserved for use in the future by interested researchers. Accessions to be included in the USDA germplasm collection were 50 cucumbers, 30 melons, 51 watermelons, and 15 luffas. As a result of the visit, cucurbit scientists in the two countries learned about the programs of their counterparts, and are planning cooperative research for the future.
A Survey of Chinese Plants of Potential Ornamental Value for the Southeastern United States
Authors: Zhang Donglin , Lasseigne F. Todd , Dirr Michael A.
Published: February 2019

China, E.H. Wilson's “Mother of Gardens”, is a large untouched resource of ornamental plants to this day. Southeastern gardens and arboreta teem with plants from China, which boasts the most diverse temperate flora in the world with more than 30,000 species described. Because of China's unique geography, climate, and floristic similarities to the southeastern United States, many of these ornamental plants should be adaptable. Based on studies of the phytogeography, floristics, history of plan; hunting, and performance of plants already introduced into cultivation from central and southeastern China, ≈500 potentially “new” species of Chinese woody plants are presented for ornamental evaluation. Characterization of the species' geography and climatic preferences in China will allow horticulturists to more accurately predict the species' performance throughout the Southeast. Zone maps exist for the United States and China that equate geographic areas on a temperature basis. However, these zone maps do not reflect the wide microclimatic differences (such as those contributed by elevation) that occur in the climatic zones. The results of this survey should enhance interest in the wonderful diversity of Chinese plants. Maps of areas already explored in the past (George Forrest, Ernest H. Wilson, and other contemporary explorers) as well as maps of suggested areas which have not been fully botanized are presented for review.
Nutritional Contribution of Home Gardens in Rural Areas of South Sumatra, Indonesia
Authors: Lakitan Benyamin
Published: February 2019

Based on their land physical conditions, house yards in rural areas of South Sumatra can be classified into six major types. Home garden models for each type of house yard had been developed. The objective of this study was to evaluate contributions of the applied models in fulfilling nutritional requirements of rural families in South Sumatra. Results of the study indicated that home gardens could contribute only <12% of protein, <10% of minerals, and <25% of vitamin B required by the families. However, of 40 villages studied, ≈20% and 34% of the families could fully received their vitamins A and C, respectively, by consuming crops produced at home gardens. Low contribution of home gardens on protein, minerals, and vitamin B was mainly related to small acreage, low fertility status of the land, and kind of crops grown. Major sources of vitamins A and C were fruits and vegetables.
Compost Mulch, Canola Cover Crops, and Herbicides affect soil Fertility, Apple Tree Yield, and Nutrition
Authors: Merwin Ian , Biltonen Michael , Ray John A.
Published: February 2019

Three orchard groundcover management systems (GMSs) were established in a newly planted apple (Malus domestica cvs. Liberty, Nova Easygro, and NY84828-12 on Malling 9 rootstock) orchard on a silty-clay loam soil (Aeric Ochraqualf). The GMSs were applied in 2-m-wide strips within tree rows as follows: 1) a 6-cm-thick mulch layer of composed manure, straw, sawdust, and vegetable plant wastes applied in May 1992 and 1994; 2) a “green manure” cover crop of canola (Brassica campestris cv. Humus) seeded in mid-August each year and tilled under the following May; and 3) Post-emergence applications of N-(phosphonomethyl) glycine (glyphosate) herbicide (2.0 kg a.i./ha) in mid-May and July each year. After 3 years of GMS treatments, apple tree growth and trunk cross-sectional area were similar in all three systems. Fruit yield and yield efficiency were greater in glyphosate and compost than in canola GMSs, and `Liberty' was the most productive cultivar. Topsoil N, P, K, Ca, Mg, Zn, and organic matter content were all substantially greater in the compost GMS. Leaf N, K, and P concentrations were consistently greater in trees in compost plots; leaf Ca, Mg, Cu, and Zn concentrations were lower in compost GMS. Weed growth was rank and difficult to control in the compost mulch, but this GMS substantially enhanced orchard soil fertility.
Comparison of Near-infrared Reflectance Spectroscopy and Standard Laboratory Analysis of Turf Soil Profile
Authors: Couillard Andree-Ann , Turgeon A.J. , Shenk J.S. , Westerhaus M.O.
Published: February 2019

The ability to predict moisture and organic matter contents as well as soil particle size distribution of a golf course turf media with the use of near infrared reflectance spectroscopy (NIRS) was investigated. This study compared a new quick test, NIRS, with the use of wet chemical analysis for the evaluation of different soil characteristics. Samples were taken from greens and fairways of central Pennsylvania golf courses and from two turfgrass research centers at The Pennsylvania State Univ. Fresh samples were vertically scanned by 1.27-cm increments, from 400 to 2500 nm, with a near infrared monochromator. Moisture and organic matter contents were evaluated in the laboratory. The pipette method was used to determine the particle size distribution. Correlations of 84% and higher were obtained for the sand, silt, and clay values as well as for the moisture and organic matter contents. NIRS analysis of soil characteristics could become a convenient, rapid, and inexpensive alternative to wet chemical analysis for golf course management.
Soil Water, NH4, and NO3 Retention in Low-maintenance Annual Landscape Beds Amended with a Hydophilic Polymer
Authors: Boatright Jennifer L. , Zajicek J.M. , Mackay W.A.
Published: February 2019

Two experiments were conducted in which a polyacrylamide gel (Hydrosource, Western Polyacrylamide) was incorporated into 56 × 38-cm, raised, concrete beds, 20 cm deep, with a drain pipe in the center of each bed. In Expt. 1, treatments included (in grams of i.a. N) 0, 186, 372, or 558 plus 0 or 366 g hydrogel/m2, for a total of eight treatments. Each treatment was replicated three times. Petunia plants were transplanted into each plot for a total of 30 plants per treatment. Plants were kept well watered. Polymer incorporation had no effect on soil water retention, soil NO3 or NH4 retention, or plant growth. Expt. 2 included treatments of 0 or 186 g of ai N and 0 or 366 g hydrogel/m2. Each treatment was replicated six times with 10 plants per replication, resulting in a total of 60 plants per treatment. Minimal irrigation was imposed on treatments. This study demonstrated that under suboptimal conditions of minimal irrigation and fertilization, polymer incorporation significantly increased soil moisture (17%), NH4 retention (83%), and NO3 retention where additional N was added (64%) compared to soils without polymer.
Effect of Composted Paper Sludges and Municipal Waste Compost Amendments on the Growth of Kentucky Bluegrass
Authors: Laganière M. , Lecomte P. , Desjardins Y.
Published: February 2019

In Quebec, commercial sod is produced on >3000 ha. Generally, ≈20 months are required to produce market-ready sod. When conditions are suitable, harvest of marketable sod is possible within a year. However, intensive management may result in soil compaction and a reduction of the organic matter content. Considering the increasing amount of amendment available, sod production fields could be interesting for their disposal. In this study, visual quality and sod root growth was examined following an application of an organic amendment at 50, 100, and 150 t·ha–1, incorporated to depth of 6 or 20 cm. Plots established on a sandy soil receiving organic amendments had higher visual quality ratings. Bulk density was significantly reduced following compost or paper sludge application to a heavy soil. The shearing strength required to tear sod amended with compost was significantly higher in comparison with control and paper sludge treatments.
Paclobutrazol Influences Salinity Responses of Peach and Olive
Authors: El-Kashab A. Abu , El-Sammak A.F. , Elaidy A.A. , Salama M.l. , Rieger M.
Published: February 2019

We studied the effect of a 200-mg·liter–1 foliar application of paclobutrazol (PBZ) on growth and physiological responses of Prunus persica `Nemaguard' (salt-sensitive) and Olea europea `Manzanillo' (salt-tolerant) to salt stress. One-year-old trees were grown in 3 sand: 3 field soil: 4 pine bark media in 20-cm pots in a greenhouse and were irrigated with nutrient solutions adjusted with 0, 9, 18, or 36 mmol NaCl for peach and 0, 36, 72, 108 mmol NaCI for olive. Dry weight, photosynthesis, and leaf conductance decreased with increasing salinity for both species. However, leaf expansion rate was unaffected by NaCl. PBZ reduced dry weight for peach only, but PBZ increased photosynthesis and reduced leaf expansion rate for both species. Relative water content was decreased by salt but increased by PBZ. PBZ reduced the foliar Na and Cl content in peach but not olive. Olive had less Na in leaves than peach at 36 mmol NaCI, accumulated less C in leaves in all salt treatments, and had higher foliar Na without symptom expression. PBZ may reduce salt stress in sensitive species like peach by reducing foliar Na and Cl accumulation but has less influence on the salinity response of the more salt-tolerant olive.
Nuclear Magnetic Resonance Imaging of Grape Buds during the Photoperiodic Induction of Dormancy
Authors: Fennell Anne , Line M.J. , Faust M.
Published: February 2019

Changes in water status have been associated with various stages of dormancy and freezing tolerance in woody perennials. Recent studies in apple indicate that changes in the state (bound vs. free) of bud water are strongly correlated with the end of dormancy. In this study nuclear magnetic resonance imaging (NMRI) was used to monitor changes in the state of bud water during the photoperiodic induction of endo-dormancy in Vitis riparia. Bud water status was monitored using proton relaxation times from T1 and T2 images determined at 2, 4, and 6 weeks of long (LD) or short (SD) photoperiod treatments. Bud dormancy was determined by monitoring budbreak in plants defoliated after photoperiod treatments. NMRI allowed nondestructive monitoring of changes in tissue water state. T1 and T2 maps indicated changes in the state of the water in bud and stem tissues during the 6 weeks of treatment. Differences in relaxation times for nondormant and dormancy-induced (reversible) buds were not clear. However, T2 relaxation times were lower in the dormant buds than in the nondormant buds.
Image Analysis Study of Aluminum Effects on Osmotic Behavior of Red Beet (Beta vulgaris L.) Protoplasts
Authors: Lee Young Sang , Mitiku G , Endress A.G.
Published: February 2019

The hypothesis that Al3+ interferes with membrane biophysical properties has been tested. Plasma membrane expansion/contraction in protoplasts isolated from red beet was induced by decreasing or increasing the osmolarity of extracellular solutions. The percentage of Iysed protoplasts was measured to characterize the effects of Al3+ on the ability of protoplasts to increase their plasma membrane surface area. In control solutions (800 mM sorbitol), 31.4% of protoplasts Iysed following osmotic dilution from 1200 mM. Al3+ treatment (5 mM) decreased the proportion of Iysed protoplasts by 7.7% and Ca2+ (5 mM) by 17% compared to control. Lanthanum (La3+), however, proved to be the most efficient ion for protection against Iysis (3.3%). Under hypertonic solutions, Al3+ treatment helped protoplasts maintain their roundness, diameter, and cross-sectional area compared to the control (1.5 M sorbitol), thus, altering the protoplasts “roundness” as determined by image analysis parameters. The results suggest that a decrease in the proportion of Iysed protoplasts in the presence of Al3+ may be induced due to changes in membrane permeability to water.
Growth Effects of Uniconazole, Gibberellin, and Calcium on Salt Injuries of Hibiscus syriacus and H. hamabo seedlings
Authors: Huh Moo R. , Kwack Beyoung H. , Perry Leonard P.
Published: February 2019

Shoot length, leaf length and width, root length, and crown diameter were affected by 0.0-, 0.5-, 1.0-, and 5.0-mg·liter–1 uniconazole drench and 25- or 50-mg·liter–1 GA3 spray but not significantly by 0.0%, 2.5%, and 5.0% NaCl. Leaf width of H. syriacus Sieb. & Zucc. was not affected and that of H. syriacus L. significantly decreased, as NaCl concentration increased. Effect of NaCl on H. syriacus leaf width was offset by treatment with uniconazole but not by GA3 treatment. With 2.5% NaCl, dry weight of H. hamabo treated with uniconazole or GA3 increased and that of treated H. syriacus decreased. With 5.0% NaCl, dry weight of both species decreased with uniconazole or GA3. Calcium at 13.35 or 133.5 mM decreased the reduction of dry weight by NaCl treatment. The dry: fresh weight ratio of H. hamabo and H. syriacus treated with NaCl plus uniconazole was higher than that only treated with NaCl. GA3 treatment with NaCl did not affect the dry: fresh weight ratio for either species
Providing Students with Tools to Increase Their Academic Success
Authors: Stearns Dan T. , Beattie David J. , Heuser Charles W. , Morgan Perry M.
Published: February 2019

In an elective course titled “Be A Master Student”, freshmen in The Pennsylvania State Univ.'s College of Agricultural Sciences were introduced to subjects ranging from university policies and procedures to skill enhancement in note-taking, test-taking, and time management techniques. A broad knowledge of agricultural sciences at local, state, national, and international levels was developed with the goal to relate agriculture to individual and societal needs. Mentoring relationships between students and faculty developed, not only with course instructors, but also with other faculty through required interviews and one-on-one discussions. Two volunteer faculty instructors taught 20 students per section. The number of sections has increased from four in 1990 to 13 in 1994. More than 70% of incoming freshmen opted to schedule the course in 1994. Student surveys indicated that >90% of those who enrolled would recommend the class to a close friend. Performance tracking shows that studentswho enrolled in the class maintained higher grade point averages than students who did not enroll. A higher rate of retention also has been documented for students who complete “Be A Master Student”!
Institutions of a Horticulture Curriculum at College of the Ozarks
Authors: Hubbard Mark A.
Published: February 2019

College of the Ozarks is a private, liberal arts college in southwestern Missouri, and the Agriculture Dept. has recently begun instituting a variety of horticulture courses in an effort to meet the increasing student interest in horticultural science. The objective is to educate and train students in the horticulture fundamentals and specific production areas (advanced courses). Also, the College is in the process of constructing teaching and demonstration gardens to be used in conjunction with classroom instruction. These gardens will include a plant materials collection and horticultural crop production areas. Additionally, as the College requires that students work part-time at any of several work “stations” on campus, students have the opportunity to gain experience in landscaping or in production greenhouses on campus. Currently, the college has 10,000 ft2 of greenhouse space that is operated for the purposes of producing plants for campus landscaping, maintaining a ≥6000 orchid collection, and producing plants for seasonal sales. The college intends to integrate the classroom instruction, experiences in the teaching gardens, and the required work experiences to provide students with a complete horticultural education. Comments and suggestions for this budding endeavor are highly sought after.
Fruit Teaching Garden as a Collaborative Project between Horticulture and Agriculture Education
Authors: Olien William C. , Harper Joe G. , Ashe Katherine
Published: February 2019

A Teaching Fruit-Garden Project was developed as a joint project between two classes in Horticulture and Agricultural Education to develop a teaching resource for college classes, area kindergarten to 12th grade (K–12) schools, and members of the community who were interested in fruit and edible landscaping. Our teaching goal was to develop a sense of involvement in course subject matter among students. The project was based on coordination of team activity, writing across the curriculum, and hands-on learning. Final product in the horticulture course was a proposal consistent with low maintenance; sustainable production principles, including choice of fruit species and cultivars; management plan; and a preliminary site plan. Final products in agriculture education were self-contained teaching modules for K–12 school teachers, including sample lesson plans, projects, and teaching materials. Students liked combining efforts between the two classes. They also liked the idea that their efforts contributed to an on-going service to the community.
Woody Plants for the Fresh-flower Market
Authors: Schnelle Mike , Whitworth Julia
Published: February 2019

Woody cut-flower plots were planted in Mar 1994 in Lane, Okla. Eight species with 10 replications each were chosen for their potential variety of fresh-cut stems and foliage, fruit, and flowers. Not only were the woody species planted for demonstrative purposes at field days and workshops, but they also were used for harvest and analysis of their vase life. Local florists also were exposed to new potential species and queried for their initial impression of the plants' aesthetic qualities and their likelihood of acceptance by the florists' patrons.