bluuebunny/crossref_metadata_2025 huggingface dataset:
A COMPUTER SIMULATION MODEL FOR EVALUATING GREENHOUSE IRRIGATION SCHEDULING TECHNIQUES
Authors: Woerner Steven E. , Hopper Douglas A.
Published: February 2019

A computer simulation model was developed to be used in evaluating irrigation scheduling techniques and assisting irrigation scheduling decisions under greenhouse conditions in Colorado. The model simulates variable greenhouse conditions and shows how each of four irrigation scheduling techniques responds to these conditions. Reports from the model detail numbers of irrigation events, sensitivities to parameters, and forecasts water usage. The model was also used to determine appropriate accumulation triggers for Colorado conditions.

Four techniques evaluated here include: time clock control; accumulated radiation; accumulated vapor pressure deficit; combination method (radiation and vapor pressure deficit). The model has shown the combination method to be the most sensitive to changes in environmental conditions, while the time clock method proved to be least sensitive (and most wasteful of water).

The model may evaluate additional irrigation scheduling techniques by including additional parameters in the model, and may readily be adapted to different climatic regions.
IMAGE ANALYSIS, SPREADSHEETS, AND GEOGRAPHIC INFORMATION SYSTEMS: AN INTEGRATED APPROACH FOR FRUIT AND VEGETABLE MANAGEMENT?
Authors: Stutte Gary W.
Published: February 2019

Effective management of site variability has been shown to improve efficiency of chemical use, enhance of fruit quality, optimize irrigations and increase profits. Techniques for localizing and quantifying spatial variation through computer analysis of aerial imagery exist, but the detailed knowledge of soils, site history, and nutrition required for effective management of the variation often are not available in a readily accessible or timely fashion. As a consequence, the benefits of site-specific management have not been fully realized by horticultural managers. These limitations have been partially overcome by developing an information management system which integrates image analysis functions to identify crop stress, a geographic information system to relate stresses to resident and nonresident site factors, and custom spreadsheets that provide a cost/benefit analysis of various management decisions. The system allows a manager to visualize the probable impact of an intervention on variability, yield, and profits in a timely manner.
DIRECT SOMATIC EMBRYOGENESIS AND PLANT REGENERATION FROM IMMATURE OVULES IN YOOZA(CITRUS JUNOS SIEB. ET TANAKA)
Authors: Oh Sung-Do , Song Won-Seob , Lee Man-Sang
Published: February 2019

From one week through 7 weeks after artificial pollination, immature ovules of yooza(Citrus junos Sieb. et Tanaka) were excised and cultured in vitro on MT media. Even though there was only a little difference in percentage of somatic embryo formation depending upon the time of excision, immature ovules of 4-week-old showed the highest ratio of somatic embryo formation without callus outgrowth. Various growth regulators or other stimulators were added to the MT media to increase the somatic embryogenesis, In general, BAP was more effective than 2,4-D for somatic embryo formation and the combinations of 0.01mg/l 2,4-D and 0,01 or 0.1mg/l BAP were particularly effective in stimulating somatic embryo formation. When 500mg/l malt extract was added to the medium, the percentage of somatic embryo formation increased reaching as high as 86.7%. Plant regeneration from somatic embryos reached to 66.7% on the medium containing 1.0mg/l zeatin. Isozyme banding patterns were also analyzed to confirm the variations of characteristics of the plantlets derived from direct somatic embryos.
EFFECTS OF WALL EFFECT AND DISSOLVE OXYGEN ON SCALE-UP OF LETTUCE SUSPENSION CULTURE
Authors: Teng Whei-Lan , Lin Chiao. Po.
Published: February 2019

This study was initiated to solve the problem of wall effect and dissolved oxygen (DO) encountered during establishing a scale-up process of lettuce suspension culture in a fermentor. The wall effect could result in as high as 10% loss of inoculum within 24 hrs. The main reason causing wall effect was identified as foam formed from the interaction of air bubble and inoculum. Bubble isolation by a screen column could successfully solve the wall effect. The effect of dissolved oxygen was then investigated. The plantlet regeneration was increased as dissolved oxygen increased from 20% to 80%. The relationship among agitation and aeration rate as well as oxygen concentration in the air was discussed.
COLD STORAGE OF IN VITRO RUBUS GERMPLASM
Authors: Reed Barbara M.
Published: February 2019

In vitro cold storage of Rubus germplasm was investigated using several environmental conditons and types of storage containers. Shoot cultures of Rubus species and cultivars were grown in either tissue culture bags or 20 × 150 mm glass tubes and compared for plant condition and survival under various storage conditions. Cultures stored at 10 C in the dark were in poor condition after 6 months. Cultures kept at 4 C were in much better condition and had higher survival rates after 18 months when stored with a 12 h daylength rather than total darkness. Overall there were no differences in survival or condition between cultures in tubes and bags. Contamination rates were 15% in tubes and 0% in bags. Plants in tissue culture bags could be stored for 9 months at 25 C with 16 h light when the nitrogen level of the MS medium was reduced to 25% and the medium volume was increased from 10 to 20 ml per bag. Genotype differences were apparent under all conditions tested. The best storage condition for Rubus germplasm was 4 C with 12 h light. Plastic tissue culture bags were preferred over tubes due to lower contamination rates.
PLANT REGENERATION OF AVOCADO (PERSEA AMERICANA MILL) IN VITRO
Authors: Mohamed-Yaseen Yaseen , Schnell Raymond J. , Knight Robert J. , Davenport T.L.
Published: February 2019

A procedure was developed to regenerate plants via tissue culture from embryonic axes of mature avocado seeds. Explants were cultured in Murashige and Skoog (MS) medium supplemented with benzyladenine (BA) and naphthalene-acetic acid (NAA) or thidiazuron (TDZ) and NAA. Culture were kept in the dark for 7-10 days to reduce browning resulting from phenolic oxidation. Multiple shoots (5-8) were formed after transfer to light. Further multiplication were achieved using different combination of BA and NAA or TDZ and NAA. Shoots were cultured in MS supplemented with 2mg/l indolebutyric acid (IBA) for 2 weeks then transferred to MS supplemented with lg/l activated charcoal for root induction. Complete plants were obtained in vitro.
IN VITRO PROPAGATION OF GUAVA (PSIDIUM GUAJAVA L.) FROM SEEDLING EXPLANTS
Authors: Mohamed-Yaseen Yaseen , Schnell Raymond J. , Knight Robert J. , Davenport T. L.
Published: February 2019

Guava (Psidium guajava L.) is an exceptional source of vitamin. C. It is also considered to be the most important cultivated species of the Myrtel family. Shoot tip and stem node were taken from seedling germinated in Murashige and Skoog medium (MS) and cultured in the same medium supplemented with 1-3mg/l benzylaminopurine (BA) and 0.1mg/l naphthaleneacetic acid (NAA) or 0.2-2mg/l thidiazuron (TDZ) and 0.1mg/l NAA. Multiple shoots (4-6) were obtained in 4-5 weeks from culture in 1-2mg/l BA and 0.1mg/l NAA, while TDZ caused abnormal shoot growth. Shoots were rooted successfully with 100% frequency in MS medium containing 2mg/l indolebutyric acid and further elongation of shoots was achieved in MS medium, supplemented with lg/l activated charcoal. Regenerated plantlets were successfully established in soil.
EFFECTS OF CALLUS AGE, GENOTYPE, AND PLANT GROWTH REGULATORS ON PLANT REGENERATION FROM ONION SUSPENSION CULTURES
Authors: Ping Song , Peffley Ellen B.
Published: February 2019

Callus of five onion genotypes representing two species. Allium cepa and A. fistulosum, and their interspecific hybrid were used for establishing suspension cultures. Cultures were derived from callus that had been maintained on solid media and routinely subcultured for four years and from callus induced within six months of this experiment. Long-term callus from which plants were routinely regenerated and newly-induced callus were composed of cells which were, for the most-part, meristem-like with higher mitotic indices than cells from long-term callus which had been maintained as callus but had lost us capability to regenerate plants, these cells were large with small nuclei. Callus from newly-induced and long-term regenerable cultures were selected for further studies. Eight liquid media with factorial combinations of plant growth regulators were tested. Cells cultured in BDS liquid medium supplemented with 0.5 mg/l ABA and 1.0 or 2.0 mg/l 2,4-D without e-BA had higher mitotic indices and plant regeneration percentages than did cells cultured in the same media without ABA and with 6-BA. Suspension cultures from A. fistulosum and interspecific hybrids with A. fistulosum produced the highest numbers of plants regenerated.
SEWAGE SLUDGE COMPOST AS A SOIL AMENDMENT FOR HORTICULTURAL CROPS
Authors: Mellano Valerie J. , Bevacqua Robert F.
Published: February 2019

Municipal sewage sludge, previously amended with Eucalyptus tree trimmings and composted, was incorporated to a depth of 30 cm at rates of 0, 12.3 and 24.6 dry MT/ha for a field planting of onion, snapdragon, turf and spinach. In a similar subsequent planting, the sludge compost was incorpoated to a depth of 10 cm. Additional treatments address the residual effect of the material. The results indicated sludge compost incorporated to a depth of 30 cm had no effect on crop yields, but when incorporated to a depth of 10 cm there was a significant increase in yields for all test crops. No buildup of heavy metals, soluble salts or changes in soil pH that would depress crop growth were detected.

Two greenhouse experiments employed equivalent rates and the same four crops. Two materials, sludge compost and heat-dried sludge were compared. The former contained composted Eucalyptus tree trimmings. The latter did not. The results showed both materials were equally beneficial to crop growth and the presence of Eucalyptus trimmings did not decrease yields
MICROPROPAGACION DE NEPHROLEPIS EXALTATA L.
Authors: Gonzalez M. , Serpa M.
Published: February 2019

In vitro propagation of Nephrolepis exaltata L., was accomplished in 4 phases: 1. Initiation explants taken from apical portions of the stolon were cultivated in M.S. inorganic salts plus 0,4 mg/l Hcl tiamine, 100 mg/l m-inositol, 30 g/l Difco Bacto Agar at pH 5, 7. 2. Multiplication of that material in a similar medium as the one used before; but without kinetine. 3. Root of shoots took place in the multiplication medium devoided of the growth regulator substances, and decreasing sucrose to 10 g/l. 4. Plants were transplanted to sterilized medium (rice husk 2 parts, light sand 1 part, black soil 1 part, and horse manure 1/2 part), and placed under saran mesh. Starting with one explant, and considering 100% success in both the multiplicative and rooting phases, it's possible to obtain about 100.000 plants of Nephrolepis exaltata L. during a period of 6 months.
REGENERATION OF CHINESE JUJUBE(ZIZYPHUS JUJUBA MILLER) FROM IMMATURE COTYLEDONS AND SEGMENTS OF SEEDLING
Authors: Oh Sung-Do , Song Won-Seob
Published: February 2019

Immature cotyledons within nucleoulus of young fruits, 40-50 days old, were cultured on various media containing different concentrations of plant growth regulators. MS medium was most effective for callus formation, but cytokinins added to MS media containing 1.0 mg/l 2,4-D inhibited callus formation. Combination of 2,4-D and BAP was more effective than 2,4-D or BAP alone for somatic embryo formation from callus. Highest percent of somatic embryogenesis was observed on MS medium supplemented with 1.0mg/l 2,4-D and 50% sucrose. Cobalt and nickel, inhibitors of ethylene synthesis, reduced significantly the number of somatic embryos. Plantlets germinated freely from somatic embryos on MS medium containing 1.0mg/l zeatin and 0.01mg/1 2,4-D. Segments of hypocotyl, cotyledon and leaf blade were observed for callus formation, somatic enbryogenesis and plant regeneration. Shoots were directly differentiated from the callus induced from segments of hypocotyl on MS medium containing 0.1mg/l 2,4-D after 4 weeks of culture.
SPECIALIZED VEGETABLE GROWING IN KOREA
Authors: Lee Jung-Myung
Published: February 2019

Similar to many Asian countries, the production and utilization of vegetables in Korea are quite different as compared to western countries. Koreans were used to favor easy-to-grow leafy and root vegetables, but this preference is gradually shifting to other vegetables, due partially to the recent surge in per capita income and westernization of cultures. In Korea, most vegetables are being utilized in fresh state with only a few exceptions, such as Kimchi, spicy vegetables, etc. Growing technics as well as the specialized production systems of several selected vegetable crops will be introduced. These include commercial production of vegetable seed and seedlings of special kinds (grafted or plug-grown), use of virus-free garlic cloves and potato mini-tubers, hydroponic culture of lettuce and other vegetables, automation of greenhouse crop production, off-season growing, and specific growing systems for minor vegetables.
Mycorrhizal Inoculation Enhances Growth and Development of Micropropagated Plants of Avocado
Authors: Vidal M.T. , Azcón-Aguilar C. , Barea J.M. , Pliego-Alfaro F.
Published: February 2019

Micropropagated plantlets of avocado (Persea americana Mill.) exhibit a very slow rate of growth during the acclimatization phase, possibly because mycorrhizae are absent. Inoculation of plantlets with the vesicular-arbuscular mycorrhizal fungus Glomus fasciculatum (Thaxter sensu Gerd) Gerd and Trappe improved formation of a well-developed root system that was converted into a mycorrhizal system. Introduction of the mycorrhizal fungus at the time plantlets were transferred from axenic conditions to ex vitro conditions improved shoot and root growth; enhanced the shoot: root ratio; increased the concentration and/or content of N, P, and K in plant tissues; and helped plants to tolerate environmental stress at transplanting. Inclusion of soil as a component of the potting medium appeared to favor mycorrhiza formation and effectiveness. Thus, mycorrhiza formation seems to be the key factor for subsequent growth and development of micropropagated plants of avocado.
Black Polyethylene Mulch Doubled Yield of Fresh-market Field Tomatoes
Authors: Abdul-Baki Aref , Spence C. , Hoover R.
Published: February 2019

Field experiments were conducted to a) maximize total yield of fresh-market field tomato (Lycopersicon esculentum Mill.) cultivars using black polyethylene mulch (BPM), and b) increase fruit size and yield during the last 5 weeks of the production period by reducing the number of synthate sinks per plant through eliminating all flowers that appeared during this period. Unmulched treatments under trickle irrigation and multiple applications of soluble fertilizer yielded an average of 43 t·ha-1 for `Sunny' and `Pik-Rite' over the two planting dates. With BPM, total yield increased by 95% to 84 t·ha-1. Although total yield increases due to BPM over the control were highly significant in both cultivars and over the two planting dates, yield increases were higher for the early than for the optimum planting date. BPM also significantly increased early production of `Pik-Rite' but not `Sunny', and the increase in early production was more pronounced for the optimum than the early planting date. Sink reduction during the last 5 weeks of the growing season had no effect on yield or fruit weight during that period.
Stand Establishment of Fresh-market Tomatoes Sown at High Temperatures
Authors: Odell Gerald B. , Cantliffe Daniel J. , Bryan Herbert H. , Stoffella Peter J.
Published: February 2019

Primed, pregerminated, or nontreated tomato (Lycopersicon esculentum Mill.) seeds were field-sown with several soil amendments to assess stand establishment at high temperatures. Soil amendments did not consistently improve tomato stand establishment. However, covering seeds with a fine-textured calcined montmorillonite clay (Growsorb) resulted in similar or improved total percent emergence, emergence rate, and seedling shoot dry weight as compared to the soil cover (control) for nontreated, primed, or pregerminated seeds. Plug-mix (a peat-vermiculite medium) or gel-mix [a 1:1 mixture (v/v) of plug-mix and gel, starch-acrylate copolymer, or polyacrylate polymer], covered over or mixed with nontreated, primed, or pregerminated seeds, did not consistently improve total percent emergence over the soil cover. However, soil amendments generally resulted in faster emergence than the soil cover. Pregerminated seeds imbibed for 60 or 72 hours at 25C generally resulted in reduced stands compared to primed or nontreated seeds. Moisturized seeds imbibed for 48 hours at 25C had faster emergence and heavier seedling shoots than nontreated seeds, regardless of soil amendment. However, primed seeds generally resulted in faster emergence and more plants with heavier seedling shoot weights than nontreated or pregerminated seeds sown at high temperatures.
Pecan Cultivar Conversion by Grafting onto Roots of 70-Year-old Trees
Authors: Yates I.E. , Sparks Darrell
Published: February 2019

Scion wood of `Desirable' pecan [Carya illinoinensis (Wangenh.) K. Koch] was grafted onto the lateral roots of 70-year-old `Van Deman' seedling rootstocks for evaluation as an alternative to planting nursery-grown trees for orchard cultivar conversion. Grafting treatments included application of IBA, method of grafting, position of graft, and grafting time. Survival was higher for grafts treated with IBA than those without IBA, for modified bark grafts positioned beneath the soil line than for either modified hark grafts positioned above the soil line or inlay grafts, and for grafts made 6 to 8 weeks after budbreak than later in the season. Techniques developed in this study demonstrate that cultivar conversion of > 75% is possible. Chemical name used: lH -indole-3-butyric acid (IBA).
Frost Hardiness of Asparagus officinalis L.
Authors: Arora Rajeev , Wisniewski Michael E. , Makus Donald J.
Published: February 2019

Frost damage to `Jersey Giant' asparagus (Asparagus officinalis L.) spears was evaluated in noncovered and black plastic-covered field plots following a spring frost episode. In the noncovered plots, 78% of spears were killed as compared to only 17% under the plastic rowcovers. Laboratory studies using natural frost simulations indicated that the spears of both treatments were frost hardy to -2.8C. Air temperature data in the field plots during the frost episode indicated that spears in noncovered plots were at lower temperatures (-4.0 to -4.8C vs. -2.8C) ≈4 to 5 hours longer than spears under rowcovers. The large difference in the spear-kill may be due to the difference in the combined effect of the degree and duration of freezing to which the spears had been exposed.
Unequal Growth Rate of Pollen Tubes from Normal and Stringless Pea Genotypes
Authors: McGee Rebecca J. , Baggett James R.
Published: February 2019

There was no difference in percentage in vitro germination of pollen from stringless pea (Pisum sativum L.) cv. Sugar Daddy and stringy `Oregon Sugarpod II' (OSP) and `OSU 705' (705). However, pollen tubes of `Sugar Daddy' grew more slowly in vitro than those of OSP or 705. Differences in pollen tube growth rate were demonstrated in vivo following time-course pollinations involving reciprocal crosses of `Sugar Daddy' with OSP and 705, along with the selfed parents. After 8 hours, pollen tubes from stringless peas (“stringless” pollen) had entered 13% of the ovules compared with 51% for those from stringy peas (“stringy” pollen). Stringless pollen tubes entered 29% and stringy pollen tubes 66% of the ovules after 10 hours. The slower growth of stringless compared with stringy pollen tubes is a plausible explanation for previously observed deficiencies of stringless plants in segregating populations.
Microspore Developmental Stage and Anther Length Influence the Induction of Tomato Anther Callus
Authors: Summers William L. , Jaramillo Juan , Bailey Theodore
Published: February 2019

Anthers of L-680A', `Licato', and `Ailsa Craig' tomato (Lycopersicon esculentum Mill.) were plated on Doy's basal medium 1 to determine whether microspore developmental stage and anther length influence anther callus production. Although calli were induced at all stages of anther development, anthers containing prophase I-stage microspores produced the highest frequency of calli. Fewer calli were produced as microspores approached the uninucleate and binucleate pollen stage. Callus diameter also decreased as anther development progressed. Significantly larger calli were produced from prophase I than later-stage anthers. Time of anther harvest (morning vs. afternoon) did not significantly affect callus number or diameter. Anther and flower bud length both were significantly correlated with anther developmental stage, the number of anthers producing calli, and mean calli diameter. In each case, anther length exhibited a significantly better correlation than bud length.
Adventitious Juice Vesicles Produced from the Exocarp in the Citrinae (Aurantioideae)
Authors: Tisserat Brent , Galletta Paul D.
Published: February 2019

Some cultivars of mandarin (Citrus reticulata Blanco), sweet orange [Citrus sinensis (L.) Osb.], and trifoliate orange [Poncirus trifoliata (L.) Raf.] were found to have adventitious juice vesicles originating from their exocarp (peel). Several hundred green vesicles may be initiated from curvilinear stylar peel depressions of immature fruit. These vesicles develop similarly to juice vesicles from the endocarp except that, as the fruit matures, exocarp adventitious vesicles die prematurely and degenerate into a fruit surface blemish. Evidence suggests that juice vesicles and oil glands are homologous and merit reconsideration in ontological studies.
Meyer Zoysiagrass Regrowth from Sod Debris as Influenced by Herbicides
Authors: Dernoeden P.H. , Carroll M.J.
Published: February 2019

In this field study, five preemergence and two postemergence herbicides were evaluated for their ability to hasten Meyer zoysiagrass (Zoysia japonica Steud.) sod development when sod was established from the regrowth of rhizomes, sod strips, and loosened plant debris. Herbicide influence on zoysiagrass re-establishment was examined using two postharvest field preparation procedures as follows: area I was raked to remove most above-ground sod debris, whereas in adjacent area II sod debris was allowed to remain in place. Herbicides that controlled smooth crabgrass [Digitaria ischaemum (Schreb.) Muhl.] generally enhanced zoysiagrass cover by reducing weed competition. Meyer established from rhizomes, sod strips, and loosened plant debris, and treated with herbicides, had a rate of sod formation equivalent to that expected in conventionally tilled, planted, and irrigated Meyer sod fields. Effective smooth crabgrass control was achieved when the rates of most preemergence herbicides were reduced in the 2nd year. Chemical names used: dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate (DCPA); 3,5,-pyridinedicarbothioic acid, 2-[difluromethyl]-4-[2-methyl-propyl]-6-(trifluoromethyl)∼S,S-dimethyl ester (dithiopyr); [±]-ethyl 2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy] propanoate (fenoxaprop); 3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethyl)-1,3,4-oxadiazol-2-(3H)-one (oxadiazon); N-[1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine(pendimethalin);N3,N3-di-n-propyl-2,4-dinitro-6-[trifluromethyl)-m-phenylenediamine (prodiamine); and 3,7-dichloro-8-quinolinecarboxylic acid (quinclorac).
A Comparison of Turfgrass Response to Biologically Amended Fertilizers
Authors: Peacock Charles H. , Daniel Paul F.
Published: February 2019

Initial release of N from waste materials used as natural organic N carriers for turfgrass may be slow due to the need for microbial degradation. In a greenhouse study, `Rebel' tall fescue (Festucau arundinacea Schreb.) and `Tifway' bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt-Davy] growth response to a natural organic fertilizer (Turf Restore) amended or not amended with a soil-derived microbiological inoculum were compared with soluble urea using sterilized and nonsterilized soil. No interactions of soil sterilization and fertilizers were noted at 19 days after treatment (DAT). Urea fertilizer increased tall fescue growth rates by 68% in the nonsterilized soil and 126% in the sterilized soil compared to rates for turf grown with inoculated Turf Restore. Nitrogen uptake rate was 419% higher with urea-fertilized turf in the sterilized soil than for turf fertilized with inoculated Turf Restore. Soil sterilization at 33 DAT no longer affected turf response, but turf growth rate was 133% higher and N uptake 353% higher with urea fertilization than with inoculated Turf Restore. Infection of the plants with Rhizoctonia spp. at 72 DAT was unaffected by fertilizer treatments. Bermudagrass response was similar to that of tall fescue. Growth rate was 67% and N uptake 51% higher with urea than with Turf Restore through 17 DAT, regardless of inoculant addition. Amendment of the natural organic fertilizer Turf Restore with a soil-derived biological inoculant did not enhance turf growth rate or N uptake nor impact infection with Rhizoctonia spp.
Role of Self-pollination and Reciprocal Stigma/Anthers Position on Fruit Set of Eight Self-compatible Almonds
Authors: Godini A. , de Palma L. , Palasciano M.
Published: February 2019

A study to ascertain the highest possible fruit set following self-pollination of eight self-compatible cultivars of almond (Amygdalus communis L. = Prunus dulcis Mill) was carried out in Apulia (southern Italy). Fruits set from daily hand-selling were high, compared to those from unassisted self-pollination. The results support growing most of the self-compatible Apulian almonds in solid blocks, without need for cross-pollination, provided that self-pollination is optimized by insect vectors. The relative capability of the cultivars to set fruits by unassisted self-pollination was independent of the reciprocal stigma/anthers position within the same flower.
Poinsettia Cultivars Differ in Their Response to Molybdenum Deficiency
Authors: Cox Douglas A.
Published: February 2019

Six cultivars of poinsettia (Euphorbia pulcherrima Willd. ex Kl.) were grown in unlimed growth medium consisting of equal volumes of sphagnum peat and perlite. Plants received fertilizer solutions supplying Mo at either 0.0 mg·liter-1 (-Mo) or 1.0 mg·liter -1 (+Mo). In the –Mo treatment, moderate to severe symptoms of Mo deficiency (marginal and interveinal chlorosis, marginal necrosis, and downward curling of the margins) developed on the middle-aged and some recently matured leaves of `Annette Hegg Brilliant Diamond' and `Eckespoint Lilo', while some interveinal chlorosis occurred on the same leaves of `Gutbier V-17 Angelika'. No symptoms appeared on `Gross Supjibi', `Peace Regal Velvet', and `Peace Noel'. All cultivars were symptomless in the + Mo treatment. In the –Mo treatment, upper, recently matured leaves of the symptomatic cultivars and two of three symptomless cultivars had Mo concentrations at or near the critical level for deficiency; however, nitrate reductase enzyme activity was higher and NO3-N was lower in the leaves of symptomless cultivars than of symptomatic cultivars.
Pectinesterase, Polygalacturonase, and β -galactosidase during Softening of Ethylene-treated Kiwifruit
Authors: Wegrzyn Teresa F. , MacRae Elspeth A.
Published: February 2019

The activities of several cell wall-associated enzymes of the outer pericarp were assayed during softening of kiwifruit [Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa cv. Hayward] treated with ethylene. The activity of polygalacturonase (EC 3.2.1.15) increased slightly during fruit softening, while β-galactosidase (EC 3.2.1.23) activity remained constant. Salt-extracted pectinesterase (EC 3.1.1.11) activity increased during ethylene treatment, then dropped rapidly to low levels as fruit softened. Residual pectinesterase activity, extracted after digestion of the cell wall pellet with a fungal enzyme mix, decreased on softening. The rapid softening of kiwifruit in response to ethylene treatment may be initiated by an induction of pectinesterase activity, causing increased de-esterification of cell wall pectins, followed by degradation of solubilized pectin.
Carambola Growth and Leaf Gas-exchange Responses to Seismic or Wind Stress
Authors: Marler Thomas E. , Zozor Yasmina
Published: February 2019

Growth and leaf gas-exchange responses of carambola (Averrhoa carambola L.) seedlings to wind or seismic stress were studied under glasshouse conditions. Forty days of twice daily seismic stress applied for 10 seconds consistently reduced carambola height, leaf area, dry weight, relative growth rate, and leaf-area ratio, but increased trunk cross-sectional area compared with plants receiving no seismic stress. Fifty-one days of wind load reduced plant height, leaf area, dry weight, trunk cross-sectional area, net assimilation rate, relative growth rate, leaf-area ratio, and stomatal conductance compared with plants receiving no wind stress. Morphological appearance was similar for plants receiving wind or seismic stress. Net CO2 assimilation of carambola leaflets was reduced by 30 minutes of wind load for up to 6 hours following the stress. Results suggest that wind may reduce carambola growth at least partially by influencing leaf gas exchange or by the mechanical stress associated with wind.
Foliage Attributes for Current-year Shoots of Fraser Fir
Authors: Brewer J.F. , Hinesley L.E. , Snelling L.K.
Published: February 2019

Current-year shoots of Fraser fir [Abies fraseri (Pursh) Poir.] were sampled in Christmas tree plantations in western North Carolina. Needles were sampled at five positions on each shoot: 0% (proximal end), 25%, 50%, 75%, and 100% (distal end). At each position, needles were collected in a tight left-hand spiral beginning on the abaxial side (bottom) and ending on the adaxial side (top). Length, width, thickness, dry weight, and projected surface area were determined for each needle. Specific area (one-sided) averaged 45 cm2·g-1 and increased from the shoot base to the tip. On individual shoots, needle dimensions were maximal at the middle (50% position). Within sample positions, needle dimensions increased from the adaxial to the abaxial side. Needle length, weight, and area differed more than width or thickness by position. Needle surface area per centimeter of shoot was relatively stable. Regression models using shoot length, diameter, needle density, and average needle length or weight yielded good estimates of total foliage area and weight.
Impact Bruise Resistance Comparison among Peach Cultivars
Authors: Maness Niels O. , Brusewitz Gerald H. , McCollum T. Gregory
Published: February 2019

Impact testing was used to assess the variables related to bruise resistance for four peach [Prunus persica (L.) Batsch] cultivars. The effects of cultivar, ripeness, drop height, and firmness on fruit bruise incidence, bruise volume, respiration, and ethylene evolution rates of freshly harvested peaches were determined. The impact variables peak impact force, contact time, absorbed energy, and percent absorbed energy were measured at three stages of fruit ripeness and at three fruit drop heights. Each of the impact variables changed with fruit ripeness. Cultivars differed in their characteristic response to impact. Fruit impact, under the low to moderate impact energies used, had negligible effects on fruit respiration and ethylene production for the cultivars studied. Bruise incidence and volume increased with drop height and especially with advancing stage of ripeness. Under conditions we used, peach fruit bruise severity could be determined by either bruise incidence in or bruise volume of mesocarp tissue.
Postharvest Sensory and Physicochemical Attributes of Honey Dew Melon Fruits
Authors: Lester Gene , Shellie Krista C.
Published: February 2019

Physicochemical and sensory attributes of fully mature honey dew melon (Cucumis melo L. var. inodorus Naud.) fruits were evaluated 10 days after storage for eight commercial cultivars grown in two locations. Cultivars varied in degree of pref- erence expressed by panelists' ratings for overall fruit preference, flavor, and shape and for physicochemical measurements of soluble solids concentration (SSC), flesh firmness, and fruit weight. The sensory attribute that correlated most strongly with overall fruit preference was fruit flavor (r = 0.97). The whiteness of epidermal tissue (rind L value) and SSC correlated more highly with overall fruit preference (r = 0.54 and r = 0.52, respectively) than other physicochemical attributes, such as fruit firm- ness (r = -0.24) and fruit weight (r = -0.12). Epidermal L value correlated more strongly with panelists' ratings for fruit shape (r = 0.69) than with fruit flavor (r = 0.35), but SSC correlated more strongly with fruit flavor (r = 0.61) than with fruit shape (r = 0.30). Superior honey dew melon quality at harvest was associated with high SSC, white epidermal tissue, and round fruit shape.
Chitosan Coating to Extend the Storage Life of Tomatoes
Authors: Ghaouth Ahmed El , Ponnampalam Rathy , Castaigne François , Arul Joseph
Published: February 2019

The effect of chitosan on respiration, ethylene production, and quality attributes of tomato (Lycopersicon esculentum Mill.) fruit stored at 20C was investigated. Coating the fruit with chitosan solutions reduced the respiration rate and ethylene production, with greater effect at 2% than 1% chitosan. Coating increased the internal CO, and decreased the internal O2 levels of the tomatoes. Chitosan-coated tomatoes were firmer, higher in titratable acidity, less decayed, and exhibited less red pigmentation than the control fruit at the end of storage. Chemical name used: 2-amino-2- deoxy-p-D)-glucan (chitosan).
An Induced Mutation for Genie Male Sterility in Common Bean
Authors: Bassett Mark J. , Silbernagel Mathias J.
Published: February 2019

Dry seed of the common bean (Phaseolus vulgaris L.) breeding line S-593 was treated with 200 Gy of gamma radiation, and M2 seed was produced. The seed was planted at Prosser, Wash., and selection was made for plants with greatly reduced seed set. The inheritance of one of the selections for possible male sterility mutation was studied in F2, F3, and backcross generations. This character is controlled by a single recessive gene, for which the symbol ms-1 is proposed. Plants carrying ms-l/ms-1 produce well-filled pods after manual pollination with pollen from normal plants, but produce no seed when protected from insect pollination in greenhouse and field environments. Uses for this mutant are discussed.
Hydrogel as a Field Medium Amendment for Blueberry Plants
Authors: Austin Max E. , Bondari K.
Published: February 2019

Three field experiments were conducted to determine short- and long-term effects of hydrogel mixed with peatmoss, milled pine bark, or soil on growth and yield of blueberry. Rabbiteye blueberry cultivars (Vaccinium ashei Reade) Delite, Tifblue, and Climax, and southern highbush cultivar (V. corymbosum L.) Georgiagem were used as test plants. Hydrogel mixed with soil was detrimental to plant survival. Hydrogel with or without peatmoss or pine bark did not influence yield or berry weight of 3- to 4-year-old `Delite' and 2- to 3-year-old `Tifblue' plants. The southern highbush, `Georgiagem', grown in peatmoss + hydrogel, produced plants of larger volume than those grown in peatmoss alone. Yield or berry weight was not affected significantly by soil amendments. Genetic differences between cultivars affected growth, yield, and berry weight, but the cultivar x soil treatment interaction was not significant.
Response of `Himrod' Grapevines to Cane Girdling
Authors: Zabadal Thomas J.
Published: February 2019

The effect of cane girdling, in combination with the common commercial practices of gibberellic acid applications and/or other crop control, on vine size and fruit characteristics was measured over 3 years for `Himrod' grapevines (Vitis ×labruscana × V. vinifera) grown in central New York state. Cane girdles 4 mm wide between the second and third node from the base of each fruiting cane resulted in vines that were capable of sustaining vine size while enhancing several aspects of fruit quality. When added to several vine-manipulation regimes, cane girdling increased cluster weight as much as 106%, berries per cluster as much as 138%, and berry weight as much as 17%. Although cane girdling increased yield as much as 66%, it consistently reduced fruit soluble solids concentration (SSC). Therefore, for cane girdling to contribute to sustained production of quality `Himrod' table grapes in a cool-growing-season climate, it will be necessary to practice it in combination with a level of crop control that will ensure acceptable fruit SSC.
Cold Protection of Kiwifruit Plants with Trunk Wraps and Microsprinkler Irrigation
Authors: Dozier W.A. , Caylor A.W. , Himelrick D.G. , Powell A.A. , Latham A.J. , Pitts J.A. , McGuire J.A.
Published: February 2019

Own-rooted, 4-year-old kiwifruit plants [Actinidia deliciosa (A. Chev.) C.F. Liang et R. Ferguson var. deliciosa] protected by a Styrofoam insulation wrap with a water-filled pouch (Reese clip-on trunk wrap) or by microsprinkler irrigation sustained less freeze injury than unprotected plants under field conditions at temperatures as low as -17.8C. Trunk splitting occurred on the plants, but no injury was detected on canes, buds, or shoots in the canopy of the plants. Unprotected plants had more trunk splitting and at greater heights than protected plants. New canes developed from suck- ers of cold-injured plants and developed a trellised canopy the following season.
Increasing Seedling Density, Age, and Nitrogen Fertilization Increases Onion Yield
Authors: Herison Catur , Masabni Joseph G. , Zandstra Bernard H.
Published: February 2019

Three onion (Allium cepa L.) cultivar transplants were grown in the greenhouse in 200-cell plastic trays with one, two, or three plants per cell; at 75, 150, or 225 ppm N; and for 8, 10, or 12 weeks. Increasing the number of plants per cell resulted in smaller seedlings at transplanting and reduced time to maturity in the field by 1 week. Two and three plants per cell yielded more bulbs ≥76 mm in diameter, but one plant per cell had the highest percentage of bulbs ≥102 mm in diameter. Older seedlings and higher N applications produced larger plants at transplant and larger bulbs at harvest. Increasing N applications reduced maturation time slightly. Bulb fresh weight at harvest and yield of bulbs ≥76 mm in diameter were highest with 10- and 12-week-old transplants, and at 150 and 225 ppm N.
Emergence of Sugar Beet Seedlings at Low Soil Temperature following Seed Soaking and Priming
Authors: Murray Glen , Swensen Jerry B. , Gallian John J.
Published: February 2019

Seedling emergence from primed and nonprimed sugar beet seed (Beta vulgaris L.) was studied for 3 years under field conditions near Kimberly, Idaho, and compared with germination or emergence under controlled laboratory conditions. Maximum seedling emergence did not vary with seed treatment in spite of low field soil temperatures. Time to 50% of maximum emergence was significantly less for seed primed with polyethylene glycol 8000 than for nonprimed seed in only 1 of 3 years. Seed soaked in 30C water for 24 h performed similarly to nontreated seed in the field, but their maximum emergence was significantly improved compared with primed seed in one of two laboratory experiments. Time to 50% of maximum germination was improved by priming with or without a warm water soak in one of the two laboratory experiments.
A Whole-tree System for Gas-exchange Studies
Authors: Corelli-Grappadelli Luca , Magnanini E.
Published: February 2019

Based on a commercially available net photosynthesis (Pn) unit coupled to a custom-built chamber that does not require air conditioning, a low-cost system to measure whole-tree gas exchange in the field is described. The temperature in the chamber is influenced by air flow in relation to tree size. A flow of 20 liters·s-1 (equal to ≈1.5 chamber volume changes/min) was sufficient to maintain the leaves of an 11-year-old `Golden Delicious'/M.27 tree at a temperature similar to that of the ambient air and control CO2 gradients in the chamber. The system has been in operation on apple (Malus domestica Borkh.) trees for up to 4 months without modifying tree behavior.
Abscisic Acid Accumulation in Leaves and Cultured Cells during Heat Acclimation in Grapes
Authors: Abass Mageed , Rajashekar C.B.
Published: February 2019

Heat tolerance and endogenous ABA levels in leaves and cultured grape cells (Vitis spp., cultivars Venus and Veeblanc) were evaluated during beat acclimation. Plants and cultured cells were acclimated at 38 and 36C, respectively. Heat tolerance increased rapidly after exposing plants or cells to acclimation temperatures, reaching a maximum after 10 to 16 hours and 10 to 12 hours for leaves and cultured cells, respectively. Free and bound ABA levels increased sharply during the first hour of heat acclimation, before leaves and cultured cells reached their maximum beat tolerance. The increase in ABA during heat acclimation was 2- to 3-fold that of the nonacclimated control, and the time of the ABA accumulation peak in tissue roughly corresponded to the maximum heat tolerance in leaves and cultured cells. Heat tolerance was induced in cultured cells by exogenous ABA application. Heat tolerance increased significantly after 24 hours of ABA application at 7.6 or 9.5 μm. The results suggest that ABA may be a factor in high-temperature acclimation and beat-tolerance induction in grapes. Chemical name used: abscisic acid (ABA).
Eggplant Yield in Response to Potassium Fertilization on Sandy Soil
Authors: Hochmuth G.J. , Hochmuth R.C. , Donley M.E. , Hanlon E.A.
Published: February 2019

`Classic' eggplant (Solanum melongena L.) responses to K fertilization were evaluated in Spring and Fall 1991 at Live Oak, Fla., on soils testing low in Mehlich-1 extractable K. Total season yield leveled off at 51.1 t·ha-1 with 94 kg K/ha fertilization in spring and at 53.3 t·ha-1 with 60 kg K/ha in fall. Critical K concentrations (in grams per kilogram) in whole leaves were ≈45 at first flowering, 35 at early fruiting, 30 during harvest, and 28 at the end of seven harvests. Fresh petiole-sap K critical concentrations (in milligrams per liter) were ≈4500 to 5000 before harvest and 4000 to 4500 during harvest. Less than 3500 mg K/liter in fresh sap indicated K deficiency in fruiting plants. The Mehlich-1 soil extractant procedure predicted similar responses at the two sites; however, yield responses showed that the two sites differed in fertilization requirements. Fertilizer recommendations for K at both sites exceeded eggplant K requirements.
Over-tree Irrigation in Pear Orchards Influences Persistence of Foliar Residues of Four Pesticides
Authors: Sugar David , Westigard P.H.
Published: February 2019

Residues of two fungicides (dodine and fenarimol) and two insecticide/acaricides (amitraz and formetanate) on pear (Pyrus communis L.) leaves were reduced by over-tree sprinkler irrigation applied 24 or 72 hours after pesticide treatment. The difference in residue persistence following over-tree irrigation applied at 24 vs. 72 hours after pesticide treatment was significant only for fenarimol. Residues on leaves from nonirrigated trees at 96 hours post-treatment had declined 24% to 57% from initial levels. Over-tree irrigation further reduced residues by 14% to 47%. For all compounds except dodine, foliar residues measured at 96 hours post-treatment were reduced from initial levels to a greater extent by factors other than over-tree irrigation. Chemical names used: dodecylguanidine monoacetate (dodine); α-(2-chlorophenyl)-α-(4-chlorophenyl)-5-pyrimidinemethanol (fenarimol); N'-(2,4-dimethylphenyl) -N-[[(2,4-dimethylphenyl) imino]methyl] -N-methylmethanimidamide (amitraz); N,N-dimethyl -N'-[3[[(methylamino) carbonyl]oxy]phenyl]methanimidamide (formetanate).
Compositional Nutrient Diagnosis of the Greenhouse Tomato
Authors: Parent L.E. , Karam A. , Visser S.A.
Published: February 2019

Compositional nutrient diagnosis (CND) norms were computed from a diagnosis and recommendation integrated system (DRIS) databank as means and sds of CND multinutrient ratios and CND factors characterizing the high-yielding subpopulation of greenhouse tomato (Lycopersicon esculentum Mill.) plants during the 3- to. 8-cluster developmental stages. A CND multinutrient ratio is a row-centered logratio corrected for the bounded-sum constraint to 100% of all components, including a filling value between known components and 100%. CND multinutrient ratios for N, P, K, Ca, and Mg were reduced to three dimensions by principal component analysis (PCA). Varimax-rotated factors–(N-K-Ca+), (Ca+Mg-), and (P–)—were designated as contrasts describing nutrient status and equilibria in diagnostic tissues. CND nutrient indexes for N, P, K, Ca, and Mg were highly correlated with their DRIS counterparts (r = 0.964 to 0.987), using 20 independent observations. Since CND is compatible with PCA, CND could expand DRIS to a multivariate diagnostic approach projecting structured information on nutrient data into a Euclidean space. A critical sphere specific to a developmental stage could delineate the high-yielding subpopulation for diagnostic purposes. The critical radius defined using a probabilistic approach to capture the high yielders should be validated with independent fertilizer experiments.
Mechanical Fruit Thinning Influences Fruit Quality, Yield, Return Fruit Set, and Cold Injury of Pecan
Authors: Smith Michael W. , Reid William , Carroll Becky , Cheary Becky
Published: February 2019

Pecan [Carya illinoinensis (Wangenh.) C. Koch] fruit were thinned from `Mohawk' trees in Oklahoma and `Giles' trees in Kansas with a mechanical trunk shaker. All trees bore an excessive crop load before shaking. Fruit thinning improved the kernel percentage, individual nut weight, and kernel grade of `Mohawk', but nut characteristics of `Giles' were not affected by fruit thinning. Cold injury, caused by a sudden temperature drop in November, was positively related to the percentage of fruiting shoots in both cultivars. Fruit set in 1992 was negatively related to the percentage of fruiting shoots in 1991 in both cultivars. Consistent annual fruit set could be induced in `Giles' by fruit thinning, but return fruit set in `Mohawk', even at high levels of thinning, was low. Fruit thinning reduced yield the year of thinning in both cultivars. Thus, `Mohawk' trees should be thinned so that 50% to 60% of shoots bearing fruit at mid-canopy height would remain, and `Giles' trees should be thinned similarly to 65% to 70%.
Threshold Leaf Levels of Zinc that Influence Nut Yield and Vegetative Growth in Pecan
Authors: Sparks Darrell
Published: February 2019

The modified Mitscherlich plant growth model was used to quantify the threshold leaf Zn level influencing nut yield and vegetative growth, on an orchard basis, for pecan [Carya illinoinensis (Wangenh.) C. Koch]. Four indices of tree performance, including percentage of trees without deficiency symptoms, vegetative growth, nut yield, and trees without deficiency symptoms plus nut yield, were analyzed with regard to leaf Zn concentration. Data available from published and unpublished sources on any single performance index were combined for mathematical modeling. The threshold value for leaf Zn was determined to be ≈50 μg·g-1 for these tree performance indices. Thus, nut yield and vegetative growth in an orchard will be reduced with a leaf Zn concentration below ≈50 μg·g-1, but will not be affected above this value.