bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation, Characterization, and in Situ Hybridization Studies of the Abundantly Transcribed Potato (Solanum tuberosum `Superior') Homeobox cDNA POTH1
Authors: Hart Jennifer K. , Hannapel David J.
Published: February 2019

Homeobox genes contain sequences coding for DNA-binding motifs. These sequences are highly conserved across both the animal and plant kingdoms. Members of this gene family code for transcription factors that are key regulators of developmental organization. In an attempt to further elucidate the developmental process of tuberization in the potato plant, a full-length homeobox cDNA has been isolated via sequence homology from an early tuberization stage cDNA library constructed from 4-day axillary bud tubers. This cDNA, POTH1, has been sequenced and characterized by Southern blotting, northern analysis, sequence comparison, and in situ hybridization. POTH1 is shown to be a class I homeobox gene with 45% overall similarity to Kn-1 of maize and 73% match in the homeobox region. Messenger RNA accumulation studies indicate that POTH1 mRNA, unlike most homeobox transcripts, is not limited to a particular organ or developmental stage. Instead, POTH1 mRNA accumulates in rapidly growing cells of the potato plant: the apical meristems, the vascular cambium, the edges of young leaves, axillary buds, and root tips. In situ studies indicate accumulation of POTH1 mRNA in the tunica and corpus layers of the apical dome of the shoot apex and the stolon apex. In the stolon, growth and proliferation of the parenchymal cells associated with the vascular cambium contribute to swelling during early stages of tuberization, and this tissue accumulates POTH1 mRNA. It is possible that POTH1 may be posttranscriptionally regulated in a particular organ or stage of growth, or that it is involved in a wider range of growth processes than most plant homeobox genes.
Validating a Crop Production Budget for Containerized Specialty Vegetables
Authors: Lamberts Mary , Gordon Sylvia , Fitzpatrick George
Published: February 2019

Growers producing new crops often do not understand how to price individual items. The prices of common container nursery stock items may be listed in monthly trade publications. Prices for fruits and vegetables fluctuate on a daily basis. A production budget for containerized specialty vegetables was adapted from one developed for ornamental nurseries, using some specific costs for field-grown vegetables. This gave a realistic way to calculate prices for individual products. Once the crops had been sold, the authors were able to validate the model by comparing actual costs with projected costs.
A CIELAB Color Classification Scheme for Poinsettias
Authors: Bible Bernard B. , McAvoy Richard J.
Published: February 2019

Forty-two poinsettia cultivars were grown as a 15-cm single-plant pinched crop at 21/16.5°C (day/night) temperatures during Fall 1995 with standard commercial practices for irrigating, fertilizing, and pest control. On 7 Dec., 156 consumers rated the cultivars for their overall appeal. On 11 Dec., color coordinate (CIELAB) readings for bracts and leaves were taken with a Minolta 200b colorimeter. The colorimeter was set to illuminate C and has a 8-mm aperture. Bracts and leaves were placed on a white tile background for colorimetric readings. In 1996, a similar evaluation was conducted with 55 poinsettia cultivars. Using the L-value of leaves as a criterion, cultivars were separated into medium green-leafed and dark green-leafed groupings. For bracts among the red types, hue angle values were used to separate cultivars into cool red types (hue angle ≈20–22°) and warm red types (hue angle ≈24–25°). Based on the 1995 study, cultivars within the cool red bracts and dark green foliage group—those that were darker, duller red (lower L and chroma)—were less attractive (lower consumer ratings) than lighter, more-vivid red cultivars. For cultivars within the cool red bracts and medium green foliage group, consumers preferred the darker duller red cultivars. Perhaps dark foliage gives a more pleasing contrast with the more vivid cool reds than does the medium green foliage. In general, consumers rated red cultivars hire than non-red cultivars.
Volatile Profiles of Decaying Apple Fruit
Authors: Mir N.A. , Beaudry R.M.
Published: February 2019

The changes in volatile-aroma of Penicillium expansium and Botrytis cinerea fungi and apple fruit inoculated with these fungi were studied using GC-MS. A specially designed chamber with raised end glass tubes with access ports fitted with Teflon-lined septa was used to determine the volatile profile for fungi on agar. Inoculated fruit were placed in glass flow-through chambers similarly fitted with sampling ports. Volatile collection from fruits or fungi was accomplished using solid phase micro-extraction (SPME) device (Supelco, Inc.). In fungi-inoculated fruits, volatiles not produced by uninfected fruit included formic acid, 2-cyano acetamide; 1-hydroxy-2-propanone, and 1-1-diethoxy-2-propanone, which were initially detected 6 hr after inoculation. These new volatiles are suggested to be synthesized specifically by the action of fungi on fruits as they were not detected from fungi that were grown on agar or bruised fruits. In general, esters, alcohols, aldehydes, ketones, acids, and hydrocarbons other than α-farnesene declined in fungi infected fruits.
Preventing the Development of Post-production Leaf Yellowing in Easter Lily with Growth Regulators
Authors: Han Susan S.
Published: February 2019

The marked effects of growth regulators such as GA3 and BA in delaying leaf yellowing on excised leaves of Easter lilies decreased when studies were conducted on intact plants in a simulated interior environment. Solutions containing benzyladenine (BA) delayed the development of leaf yellowing in cold-stored plants, but solutions containing gibberellic acid (GA3) were not effective when applied to plants at the puffy bud stage and evaluated in a 22.6 ± 0.2°C room illuminated 12 h/day with 11.2 ± 0.1 μmol·s–1·m–2 cool-white fluorescent lamp. Treatment with commercial products containing GA4+7 (Provide) or GA4+7 and BA (Promalin) nearly completely prevent the development of leaf yellowing. Concentrations as low as 25 mg·L–1 were effective. The prevention of leaf yellowing by growth regulators was only effective on leaves that had been treated, indicating that mobilization of the growth regulators in the plants did not occur. Growth regulator solutions halted further development of leaf yellowing when applied to plants that already possessed some chlorotic, basal leaves. The striking effects of growth regulators on preventing leaf yellowing did not affect the development and opening of the flower buds and is a practical solution for the prevention of post-production leaf yellowing in Easter lilies.
Bulb Quality and Traumatic Acid Influence Bulblet Formation from in Vitro Micropropagated Lilium Species and Hybrids
Authors: Marinangeli Pablo , Curvetto Nestor
Published: February 2019

Micropropagation is an advantageous technique for commercial Lilium propagation. The aim of this work was to evaluate the impact of genotype, traumatic acid [TA, 10(E) dodeca-1,12-dicarboxylic acid] treatment and an initial bulb quality on lily in vitro propagation. Genotypes were: L. longiflorum Thunb. `Snow Queen', L. lancifolium Thunb., one Oriental hybrid (L. × `Stargazer'), and four Asiatic hybrids (L. × `Enchantment', L. × `Connecticut King', L. × `Sunray', L. × `Cote d'Azur'). Assays were done with good-quality bulb genotypes—chosen by water content, sprouting degree, and appearance—with exception of L. × `Cote d'Azur', where poor-quality bulbs were also included. Surface-sterilized 3-mm scale bulb sections where cultured in MS medium with 100 mg·l–1 myo-inositol, 0.4 mg·l–1 thiamine·HCl, 0.1 mg·l–1 NAA, and 3% sucrose and 0.8% agar, pH 5.7. Cultures were kept in darkness at 25°C during 8 weeks. One μM TA was used to immerse half of the explants during 1 hr before culturing. Genotypes showed a wide variability in bulblets' number (1.7–2.9 bulblets per explant) and biomass (55–147 mg per bulblet). The same variability was observed after TA treatment, which produced an increase in bulblets number per explant (14% to 59%) and also a significantly augmented their fresh mass (9% to 42%). Poor-quality L. × `Cote d'Azur' bulbs adversely affected both biomass and number of bulblets produced on the scale sections, which was not overcome with TA treatment. These results suggest the convenience of TA application in Lilium micropropagation protocols on good-quality bulbs, irrespective to the genotype source.
Flow Rate as an Important Physiological Factor Associated to Calcium Concentration in Pods of Snap Bean (Phaseolus vulgaris L.) Plants Grown Aeroponically
Authors: Quintana Juan M. , Harrison Helen C. , Palta Jiwan P. , Nienhuis James
Published: February 2019

To understand physiological factors associated with genetic differences for pod Ca concentration between snap bean genotypes, flow rate and Ca uptake of sieve sap were measured, as well as pod Ca concentration. Measurements for flow rate and Ca uptake were done at three developmental stages (fl owering and 1 and 3 weeks after) in two commercial snap bean cultivars (Hystyle and Labrador) grown aeroponically. Pods were collected 2 weeks after flowering only. Flow rate and Ca uptake sampling began 4 weeks after transplanting and consisted of: 1) decapitation of the plant at the first node; 2) covering the stem with pre-weighed dry cotton; and 3) removing the cotton, reweighing it, and saving it for Ca determination. Flow rate was defined as the difference in cotton weight (expressed as ml) per 17 hr divided by foliage mass. Ca uptake was defined as mg of Ca per total volume of sieve sap after 17 hr divided by foliage mass. Ca determinations were made using an atomic absorption spectrophotometer. A positive correlation between flow rate and total Ca uptake of sieve sap (R2 = 0.90), flow rate and pod Ca concentration (R2 = 0.47), and Ca uptake and pod Ca concentration (R2 = 0.42) were found. Hystyle reflected 1.5 times more flow rate and pod Ca concentration than Labrador. Significant differences between genotypes for pod Ca concentration, Ca uptake, and flow rate were observed. Results were consistent across developmental stages.
Light Quality Effects on Flower Sex Expression in Cucumber and Spinach
Authors: Bachman Gary R. , McMahon Margaret J.
Published: February 2019

Using spectral filters to reduce the amount of far-red (FR) light perceived by plants has been shown to effectively reduce internode elongation of many floriculture crops. It is theorized that gibberellin (GA) function is inhibited in some way by the increase in the red: far-red light ratio. Sex expression of flowers are effected by exogenous applications of gibberellin and cause a shift in flower sex expression towards maleness. The use of growth regulators (GA inhibitors) have demonstrated a shift towards femaleness. Flowering of spinach, a dioecious species, and cucumber (staminate and pistillate lines), a monoecious species, were surveyed for shifts in flower sex expression, indicating a suppression of GA. Male: female flower ratio decreased from 7.6:1 to 4.06:1 when comparing the controls and –FR for the staminate cucumber line and 1:13 to 1:40 for the gynecious cucumber line. The decrease in male flowers on plants grown in a –FR environment are an indication that the function of GA is inhibited. There was no significant effect on the male: female flower ratios of the spinach.
Use of Sphagnum Peatmoss in a Composting Process
Authors: Daigle Jean-Yves
Published: February 2019

The general population is constantly reminded of the need to adopt a more environmental-friendly approach to waste disposal on all scales. Commercial fishing generates large proportions of waste, ranging from 40% to more than 80% of the catch! The objective of conserving the nutrients and other organic values contained in this type of waste is unlikely to be fully met by bulking for aerobic composting with materials of low buffering capacity, such as straw or wood wastes. However, the capacity of peat for deodorizing of decomposing organic wastes as well as its high buffering capacity has been well demonstrated. This presentation shows how the incorporation of sphagnum peatmoss in a composting process contributes significantly to the production of a valuable organic soil amendment.
Evaluation of Fire Blight Resistance of Malus sieversii Populations from Central Asia
Authors: Momol M.T. , Lamboy W.F. , Forsline P.L. , Aldwinckle H.S.
Published: February 2019

Malus sieversii is one of the primary progenitors of the cultivated apple. Since 1989, several collecting trips have been made to central Asia by personnel of the USDA and Cornell Univ. to collect seeds of wild Malus sieversii from many diverse ecosystems. In 1992, an ex situ plot in Geneva, N.Y., was established with trees grown from seed that was collected in three different habitats in Kazakstan, Tajikistan, and Uzbekistan in 1989. In 1995, trees grown from seed that was collected in five additional habitats in Kazakstan and Kyrgyzstan in 1993 were added to the ex situ plot. In the summers of 1995 and 1996, tips of vigorously growing shoots of 1135 seedlings from 79 different populations were inoculated by hypodermic syringe with 5 × 108 cfu/ml of Erwinia amylovora strain Ea273. Seedlings from the 1989 collection were in the fourth and fifth field-growing seasons, with some beginning to bear fruit. Seedlings from the 1993 collection were in first and second field-growing seasons. Results from both seasons indicated that individuals within each of the 79 populations of M. sieversii are resistant to fire blight (defined as ≤20% shoot length infected). Resistance differed among populations, with some populations having no resistant individuals and others having >80% of the seedlings resistant. The range of resistance is quite similar to that seen among apple cultivars from North America and Europe. In another test, some accessions from 1989 collection had sufficient bloom for inoculation in 1995 and 1996. At full bloom, blossoms on these trees were inoculated with the E. amylovora suspensions (5 × 107 cfu/ml) using a backpack sprayer. These also gave diverse resistant reactions.
Influence of Root Flooding Interval on Phytophthora Root Rot of Blueberry
Authors: de Silva Amal. P. , Patterson W. Keith
Published: February 2019

Phytophthora root rot is a severe disease on blueberry (Vaccinium corymbosum L.) in poorly drained soils. The objective of the study was to determine the frequency of water-logged conditions on disease severity of blueberry. Phytophthora cinnamomi was grown on rice hulls and incorporated into the soil at the rate of 10% v/v. Water logging conditions were inflicted for 48 hr on mulched and non–mulched blueberry plants at 1-, 2-, and 4-week intervals. Non-water logging conditions were used on both mulched and non-mulched control plants. There was a significant linear relationship between disease severity of shoots and roots and the frequency of water-logging conditions. Disease symptoms were low in control plants, but disease ratings were high in mulched and non-mulched plants that were treated with water-logging conditions every week. There was also a linear trend between shoot dry weight and root dry weight of plants with frequency of water logging. Higher dry weights were seen on control plants. There was a significantly higher shoot, root dry weight and number of leaves of mulched plants than non-mulched plants. The percentage of infection on roots were high with frequent water logging. The study revealed high disease incidence with frequent water loggings. However, growth of mulched blueberry plants were comparable in control plants and plants that were subjected to water logging at 4-week intervals.
Disease Forecasting on Stake Culture Tomatoes: Effectiveness of TOM-CAST Forecasts Generated from On-site or Electronic Meteorological Service Weather Data
Authors: Maletta M.H. , Cowgill W.P. , Tietjen W. , Johnston S.A. , Manning T. , Nitzsche P.
Published: February 2019

Five variations of TOM-CAST and two sources of weather data were used to schedule tomato early blight control for research trials at the Snyder Research and Extension Farm, Pittstown, N.J. TOM-CAST scheduled fungicide applications were initiated at 15, 25, or 35 disease severity values (DSV) and resprayed at 15 or 25 DSV. Weather data for generating the DSVs was obtained on-site with a Sensor Instruments Field Monitor™ or through subscription to the electronic meteorological service SkyBit, Inc. Bravo 720, 3 pints/acre, was used for disease control. Foliar disease, yields, and postharvest decays were evaluated. Daily DSVs, cumulative DSVs, and forecast spray schedule varied with weather data source. Because SkyBit data generated more DSVs during the season than Field Monitor data, the SkyBit-based forecasts called for one or two more sprays than the Field Monitor-based forecasts. However, the number of sprays actually applied was the same, one more or one less for each combination of initiation and respray thresholds. All treatment schedules reduced disease compared to the untreated control. Variation in initiation threshold did not affect disease control. All TOM-CAST schedules respraying at 15 to 20 DSV were as effective as the weekly schedule. All fungicide treatments increased total yields and reduced postharvest decays compared to the untreated control. Most treatments also increased marketable yields. The most efficient, effective Field Monitor-generated TOM-CAST schedule required nine sprays compared to 13 weekly sprays. The comparable SkyBit-generated schedule called for 10 applications. Chemical name used: tetrachloroisophtalonitrile (chlorothalonil).
Pinching of Lagerstroemia for Use as a Potted Florist Crop
Authors: Rawson James M. , Harkess Richard L.
Published: February 2019

Lagerstroemia has potential for development as a potted florist crop for early spring sales. The number and timing of pinching or number of liners per container were examined as a means of developing a more compact plant that is in proportion to the container. On 20 July 1996, either one or three rooted liners of Lagerstroemia `Victor' or `Zuni' were planted into 1500-ml (15 cm in diameter) containers in a pine bark: peat moss (3:1 v/v) substrate amended with 6 kg·m–3 MicroMax plus (Scotts Company, Inc., Marysville, Ohio). The plants were topdressed with 10 g SierraBlen 17–6–12 (Scotts Company, Inc., Marysville, Ohio) slow-release fertilizer. The liners received 0, 1, 2, 3, or 4 pinches and were pinched in a complete factorial 0, 2, 4, and 6 weeks after potting. There were 32 pinching treatments with 5 replications. The plants were grown outside until 30 Sept. 1996, when they were moved into a greenhouse. Plant height, width, and a visual rating were collected 13 Nov. 1996. There was no significant difference in plant size or visual rating of `Victor' regardless of the number or timing of pinches or of the number of liners per pot. `Zuni' had significantly the best visual ratings and largest size when grown with three liners but the timing and number of pinches had no significant effect. `Victor' is a dwarf cultivar growing to only 1 m in the landscape while `Zuni' is a semi-dwarf, growing to 2.7 m.
Cryopreservation of Sweetpotato Shoot Tips by Vitrification
Authors: Pennycooke Joyce C. , Towill Leigh E.
Published: February 2019

Cryopreservation offers the simplest and most economical way for the long-term conservation of germplasm and vitrification is the preferred method to accomplish this. Undefined endogenous compounds are produced during plant growth and shoot tip preculture conditions. These may influence “cryopreservability” and interact with cryoprotectants that are artificially added during the cryogenic protocol. We are beginning to examine these aspects to improve cryopreservation. Nodal segments of PI 296057 were propagated on a hormone-free modified Murashige and Skoog (MS) solid medium and were grown with 16 hr/8 hr photoperiod. Shoot tips were excised at 0, 3 or 10 hr in light after the dark period. Excised shoot tips were precultured in 0.06 M sucrose in MS for 24 hr and 0.3 M sucrose in MS for 24 hr and then treated with 0.4 M sucrose plus 2 M glycerol for 20 min or 1 hr before being dehydrated in PVS2 [30% (w/v) glycerol, 15% (w/v) ethylene glycol and 15% (w/v) dimethylsulfoxide in MS and 0.4 M sucrose[for 10, 16 or 26 min at 22°C. Shoot tips were placed on thin strips of aluminum foil, which were folded to enclose the shoot tips and then immersed in a liquid nitrogen (LN) slush. Rapid warming and dilution were achieved by transferring the foil strips from LN into 3 ml of 1.2 M sucrose at 22°C for 20 min. All cultures were incubated in darkness for 2 days then dim light for 3 days before transfer to the usual light intensity. Elimination of iron and nitrogen from MS medium in post thaw culture for 5 days increased the viability of LN-treated samples. Maximum survival after LN exposure was achieved with excision immediately after the dark photoperiod, cultured for 1 hr in 0.4 M sucrose plus 2 M glycerol and exposed for 16 min in 100% PVS2 at 22°C. Previously, Towill and Jarret (1992, Plant Cell Reports 11: 175–178) reported that surviving shoot tips developed callus and a variable percentage subsequently formed shoots. In this line all surviving shoot tips eventually formed shoots.
Efficient Methods to Differentiate between Transgenic and Wild-type Mosses
Authors: Mergenthaler E. , Bisztray Gy. , Coyne D.P.
Published: February 2019

As ancestors of higher plants, mosses offer advantages as simple model organisms in studying complex processes. The moss Physcomitrella patens became a powerful model system in the last few years (Cove and Knight, 1993). Adaptation of PEG-mediated DNA uptake procedure has permitted the establishment of efficient molecular genetic approaches. To study possible effects of a Type I phytochrome, the potato phyA gene was introduced into the moss P. patens. Stabile transformants exhibited a range of similar phenotypes (Schaefer et al., 1991). The aim was to differentiate the wild type from the transgenic moss plants with simple, quick measurements providing data suitable for analyzing offspring populations. Ten different morphological and biochemical methods were used to investigate the phenotype in order to choose the best phenotypical category to indicate the presence and the effect of the phytochrome transgene. Two selected strains were used with the most and the least intensive phenotypical features (3*, 29), along with their selfed progenies, as well as progenies from crosses with the nicotinic-acid auxotrophic mutant. The best methods to differentiate between wild type and transgenic plants were the statistical analysis of the number of gametophores, photometric measurement of pigment contents and composition under different light conditions, color evaluation by PC-based vision system, and visual observation of morphogenetic changes. Our investigations support that the potato phytochrome transgene has a pleiotropic effect in the moss P patens. The methods used would be applicable for the characterization of mosses with different transgenes.
Performance of Three Guava Cultivars in Middle Georgia
Authors: Yadava U.L.
Published: February 2019

Two-year-old trees of `Red Flesh' (RDF) and `Lucknow-49' (L49) guavas from India and `Beaumont' (BMT) guava from Hawaii were established in the field during Spring 1995, inside an open wooden structure equipped with electric heaters and fans. Trees were cold-protected from November to the middle of April by covering the wooden structure with 6-mil clear polyethylene and using heaters and fans. Trees of RDF grew compact, while those of L49 and BMT were open, upright, and grew taller. Other than blossom-end rot on few fruits, no incidents of insect-pest and diseases were observed on trees or fruits. All cultivars bloomed from March to June 1996. Fruit set was heavier on BMT and L49 than on RDF trees. Fruit harvest extended from Sept. 1996 to Jan. 1997. Cultivar significantly influenced harvest and fruit weight. Peak harvest date was earlier for BMT, followed by RDF and then L49. Mean fresh weight (g/fruit) was 535.7, 284.2, and 150.7 for RDF, L49, and BMT, respectively. Fully developed RDF fruits were round, sometimes flat vertically, with blush on green skin when ripe, and had a small core in red flesh. Fruits of BMT were round to elliptical, yellow when ripe, and had numerous seeds in red flesh. Fruits of L49 varied from round to elliptical to pyriform with yellow to light green skin color and cream flesh with fewer seeds in a large core. The fruit flavor was strong and astringent for both BMT and L49, whereas RDF had a mild fruit flavor.
Evaluation of Different Pear Cultivars in Northwest Mexico
Authors: Grijalva-Contreras Raul Leonel , Avilez-Peraza Victor , Fimbres-Fontes Adan , Macias-Duarte Ruben , Miranda-Blanco Jose L.
Published: February 2019

Pear production in Mexico is low; there are about 4500 ha. One of the main problems in this tree fruit is the unknown number of new varieties for each area. The objective of this study was to evaluate 23 common pear cultivars and seven Asian pears. The experiment was carried out at the Experimental Station “El Tasicuri” of Magdalena, Sonora, Mexico. The trees were planted in 1990 on Pyrus calleryana rootstock. The main results were that common pears were not adapted to the area because of the lack of cold weather; however, `Bartlett' was the only cultivar that was adapted. Asian pears showed good adaption into the region (`Shinseiki', `Kikusui', `Hosoui', `Twenty Century', and `Ya-Li'). The ripening date of these cultivars were from the 7 and 20 of Aug. and the weight of the fruit was 146 and 198 g/fruit. There were no pests or diseases in any of the Asian cultivars.
Date Production in the Coachella Valley, Southwest California
Authors: Aslan Sam , Cobb Sam , Aguiar Jose L. , Abdul-Baki Aref A.
Published: February 2019

Approximately 90% of total date production in the U.S. is localized in the Coachella Valley, southwest California. The remainder is in the bordering Imperial Valley, Calif., and Yuma, Ariz. The date trees (Phoenix dactylifera L.) occupy 2282 ha, have an annual yield of 24,000 tons, and a product value of $62 million. Major varieties include `Deglet Noor', `Khadrawl', `Zahide', and `Majhool'. Although climatic requirements for date production prevail in the Valley, major problems related to soil and water have adverse effects on yield and fruit quality. These include water and soil salinity, high water table, high soil compaction and stratification, and low fertility. Slip plowing has been a recommended practice for decompacting the soil. However, soils get recompacted by machinery used in cultural operations. We recently introduced planting cover crops in a no-till system to improve soil fertility, reduce compaction, and improve drainage.
Effects of a Combination Application of Hydrogen Cyanamid (Dormex) and Ethephon (Ethrel) on Fruiting of `Redhaven' and `Surecrop' Peach
Authors: Powell Arlie A. , Pitts James , Boozer Robert
Published: February 2019

Early flowering of peach in the southeastern U.S. often results in some annual crop loss as a result of late winter–early spring freezes. It has been shown in peach and other prunus that a fall application of ethephon delays flowering 4 to 7 days and possibly affords increased bud hardiness. However, delayed harvest and smaller fruit size of certain varieties may occur. Hydrogen cyanamide replaces lack of chilling in peach, but can also advance harvest date and possibly enhance or maintain fruit size. A randomized complete-block experimental design was used to evaluate whether hydrogen cyanamide could offset the delayed harvest and smaller fruit size disadvantages of using ethephon without advancing bloom dates over a 3-year period. Treatment combinations of ethephon (at 20%, 50%, and 90% of required chilling) and hydrogen cyanamide (at 90% to 100% of required chilling) were applied as whole-tree foliar sprays to near point of drip. Results exhibited a possible trend toward hydrogen cyanamide overcoming smaller fruit size and delayed harvest.
Seed Germination of Four Lupine Species under Differing Osmotic Condition
Authors: Mackay Wayne A. , Davis Tim D.
Published: February 2019

Seeds of four lupine species (L. microcarpus var. aureus, L. havardii, L. succulentis, and L. texensis) were subjected to 0, –2, –4, –6, or –8 bars osmotic potential using PEG 8000 solutions. Seeds of all species were acid scarified prior to placement in petri dishes containing the osmotic solutions. Petri dishes were placed in a seed germination chamber at 25°C with germination data collected daily for 15 days. Seeds of L. havardii, a desert species native to west Texas exhibited the greatest germination as osmotic potential declined while L. succulentis, a species adapted to moist sites, exhibited the greatest decline in germination as osmotic potential decreased. The other species exhibited intermediate germinability under the lower osmotic potentials.
Super-density Planting and Lower Canopy using Hardwood Cuttings of `Sunaga Wase' Peaches
Authors: Kim Wol Soo , Lim Kyong Ho , Lim Hyung Kee , Kim Byeong Sam
Published: February 2019

In order to investigate the super-density planting in peach orchards, the experiment was carried out using nursery trees out of hardwood cuttings in `Sunaga Wase' peach (Prunus persica L.). The nursery trees were planted with various planting densities of 1 × 0.5 m (20,000 trees/ha), 1 × 1 m (10,000 trees/ha), 2 × 0.5 m (10,000 trees/ha), 2 × 1 m (5,000 trees/ha), and 6 × 5 m (330 trees/ha) as traditional density on 22 Mar. 1995. As soon as fruit harvest in mid-July, the peach trees were pruned by thinning and heading-back the shoots to induce the new shoot as well as to limit the tree height and lower the canopy. During the second year after planting, nursery cutting trees yielded the most peach fruits from the planting density of 1 × 0.5 m, as much as 14.37 t, which was 14 times higher than the 6 × 5 m of traditional density, followed by 2 × 0.5 m, 1 × 1 m, 2 × 1 m, and 6 × 5 m, respectively. According to summer pruning just after harvest, remaining vegetative buds burst and then the new shoot grew very vigorously in several days. The floral bud differentiation on the new shoots was lower, as much as 32.2%, than that of 77.9% in no-pruning shoots. There were no differences in fruit characteristics among various planting densities.
Improving Production of MM.106 Apple Rootstock Stools using Hydrogen Cyanamid Dormancy-breaking Agent
Authors: Elsherbini Nabil R.
Published: February 2019

Dormex (aqueous solution of 48% hydrogen Cyanamid) was applied by the end of December at 2%, 4%, and 6% in the first season and at 3%, 4%, and 5% in the second season to 1-year-old shoots of MM.106 apple rootstock. Dormex at 4%, 5%, and 6% increased significantly the percentage of bud burst, stool diameter, stool length, internode length, and leaf area; moreover, it decreased the number of days required to reach 50% bud burst. However, Dormex at 4% and 6% enhanced the stool Grand Period of Growth (GPG) by 1 and 2 months, respectively, compared with the untreated plants. Dormex treatments resulted in a significant increase in stool content of N, Ca, and Zn.
Use of Electrolyzed Water to Reduce Bacteria on Fresh-cut Vegetables
Authors: Izumi Hidemi , Kiba Tota , Hikone Akio , Hirano Hirohisa , Kuwana Shigeji
Published: February 2019

Effect of electrolyzed water on total microbial count of several fresh-cut vegetables was evaluated. Electrolyzed water (pH 6.5), containing 20 ppm available chlorine, was produced by electrolysis of salt solution using an electrolyzed neutral water generator, Ameni Clean (Matsushita Seiko Co. Ltd., Osaka, Japan). Fresh-cut vegetables, including carrot slices, chopped bell peppers, trimmed spinach leaves, shredded Japanese radish, and diced potatoes, were treated with electrolyzed water by dipping, rinsing, or bubbling (immersion and flush with air at 25 L/min) for 3 min and then rinsed with running tap water for 1 min. These treatments reduced the total microbial count by about 1 to 2 log units on tissue surface and inside of all vegetables relative to nontreated samples. Since rinsing with tap water also reduced the microbial count by about 1 log unit, the bubbling treatment was the only effective treatment in reducing bacteria on the surface of fresh-cut Japanese radish and potatoes when compared with water-rinsed controls. When samples were not rinsed with tap water after treatment, the microbicidal effect of electrolyzed water was noted on tissue surface of all vegetables even if relative to water-rinsed controls. Electrolyzed water did not affect the tissue pH ranging from 5.7 to 6.1, surface color, and taste of any fresh-cut.
Effect of Coir and Sphagnum Peat-based Substrates on Fungus Gnat Populations
Authors: Evans Michael R. , Smith James N. , Cloyd Raymond
Published: February 2019

Fifteen-centimeter (1700-ml) containers were prepared for this experiment by sealing the drainage holes with insect screen (Hummert International, Earth City, Mo.) that had openings of 0.026 cm × 0.0805 cm. Containers were filled with substrates composed of either a 80% sphagnum peat or 80% coir. The remainder of the substrates was composed of perlite. Rooted cuttings of Euphorbia pulcherrima `Freedom' were planted into the containers and the containers were sealed with the insect screen and plants were allowed to grow and the substrate to age for 2 weeks. Fungus gnat (Bradysia spp.) larvae were collected using potato disks placed on the surface of infested substrates. After 3 days, larvae were collected from the disks, and 10 larvae were added per container. Uninoculated controls were included. After a period of 6 weeks, the adult population was sampled by placing 2.5 × 5.0-cm yellow sticky cards in each container. The larval population was sampled by placing a 4-cm-diameter potato disk on the substrate surface of each container. Fungus gnat larvae and adults were recovered from both sphagnum peat and coir-based substrates. Neither the number of adults nor the number of larvae recovered were significantly different between sphagnum peat and coir-based substrates.
Unblended or Co-blended Composts for Production of Potted Chrysanthemum
Authors: Ku Catherine S.M. , Bouwkamp John C.
Published: February 2019

Blending compost from various feedstocks may increase the beneficial effects of compost as potting substrate. A factorial treatment combinations included 10 compost combinations, Sunshine Mix and Pro Gro 300S as controls, three compost levels, and three chrysanthemum cultivars. The compost combinations were Compro (CP), poultry litter (PL), PSG polymer dewatered biosolids (PSG), yard trimmings (YT), CP:PL, CP:PSG, CP:YT, PL:PSG, PL:YT, and PSG:YT; all blends were on a 1:1 ratio (v/v). The compost levels were 50%, 75%, 100%; and chrysanthemum cultivars included `Boaldi', `Cherry Davis', and `Yellow Favor'. All treatments were replicated six times. Plants were fertilized with 100 mg/L N from 20N–8.8P–16.6K twice weekly. All compost substrates, except PSG blends produced plants that were shorter than the controls. All compost blends produced similar or greater number of flower than the controls. Plants grown in substrates containing PSG and/or CP produced dark green or green foliages, and other substrates produced plants with pale green leaves. The PSG:PL and PSG: YT blends produced premium-quality plants. All other compost blends produced good-quality plants that were similar to the controls.
The Effects of Differing Potassium Status (K) On English Walnut Tree Growth, Yield, And Nut Quality
Authors: Olson William H.
Published: February 2019

Six years of previous research in a 12-year-old English walnut orchard, with a history of potassium deficiency, created a large number of trees with different potassium status. This provided the opportunity to study the long-term effects different potassium status has on English walnut trees growth, productivity, and nut quality. Walnut trees with a history of potassium deficiency, adequacy or luxury continued in this mode during this evaluation. Positive correlations existed between July leaf potassium levels and tree trunk sectional area (TCSA), visual potassium status, percent husk potassium, yield per tree, and tree yield per TCSA. These positive correlations suggest July leaf potassium levels of 1.4% to 1.5% as being adequate. This is higher than the 1.2% leaf potassium level currently recommended as being adequate for a July sample. Poor or no correlations existed between July leaf potassium levels and percent shell potassium, shell weight, shell breaking force, percent broken shell, nut size, nut weight, percent kernel potassium, percent light-colored kernels, percent edible kernel, percent kernel yield, or percent shriveled kernel. Trees with leaf potassium levels at or above 1.5% July leaf potassium produced 80 pounds per tree more yield than trees with leaf potassium levels at or below 1.0% July leaf potassium levels. These data indicate that good tree potassium status influences tree size and tree productivity. Also the walnut husk is an important sink for the accumulation of potassium. Currently recommended adequate potassium levels for walnut appear to be lower than what this study indicates.
Solution pH and Papaya Seed Germination and Seedling Emergence
Authors: DeMeo Robin A. , Marler Thomas E.
Published: February 2019

Two studies were conducted to determine the influence of pH on papaya seed germination and seedling emergence. The germination test was conducted with `Waimanalo' and `Tainung 1' seeds, using a double layer of filter paper disks in plastic petri dishes placed within a growth chamber. Each dish received 40 seeds, and germination was defined as when the radicle was visible. Disks were wetted daily with nutrient solution adjusted to pH of 3, 4, 5, 6, 7, 8, or 9. Germination began on day 5, and the study was terminated on day 23. Solution pH did not influence germination rate or ultimate germination percentage. `Waimanalo' exhibited 58% germination and `Tainung 1' exhibited 64% germination in this test. The seedling emergence study was conducted with `Waimanalo' seeds using sand culture within a growth chamber. Thirty seeds were planted in 10-cm containers, and the sand was irrigated daily with the solutions from the first study. Emergence was defined as when the hypocotyl hook was visible above the sand. Emergence began on day 10, and the study was terminated on day 30. Solution pH did not influence seedling emergence, and mean emergence was 69% in this study. The results indicate that the seed germination and seedling emergence stages of papaya seedling growth are adapted to a wide range of substrate pH.
Mineral Relations and Growth of Annona muricata Seedlings as Influenced by Substrate pH
Authors: Marler Thomas E. , Paloma Grace B.
Published: February 2019

Container-grown Annona muricata seedlings were bare-rooted and re-potted in sand. Containers were irrigated daily with a complete nutrient solution adjusted to a pH of 3, 4, 5, 6, 7, or 8, and the seedlings were grown for ≈5 months. Numerous growth variables were measured, including canopy volume, increase in mass, and trunk diameter. There were no differences in growth measurements among the pH levels. Moreover, leaf tissue was analyzed for mineral content. Leaf tissue concentration of various minerals did not differ among the pH levels. Annona muricata is known for growing well in a range of soil conditions. These data verify that the species is adapted to a wide range of substrate pH.
The Effect of Aluminum and Media on the Growth of Mycorrhizal and Nonmycorrhizal Highbush Blueberry Plantlets
Authors: Yang Wei Qiang , Goulart Barbara L. , Demchak Kathleen
Published: February 2019

A factorial experiment was conducted to determine the effect of aluminum (0 and 600 μM) and media (sand, and 1:1 sand:soil) on mycorrhizal (M) and non-mycorrhizal (NM) highbush blueberry plantlets. There were no differences in nutrient uptake and total plant dry weight between M and NM plantlets. However, more root growth, as determined by dry weight, was observed in M than NM plantlets. The plantlets growing in sand had more dry weight than did those in the soil medium. Although the root growth and shoot growth were reduced by the 600-μM Al treatment, the direct effect of Al on plantlet growth was not clear due to Al and P interactions. Plant nutrient uptake was reduced by high concentrations of Al, suggesting that high Al concentration limited the ability of roots to acquire most of the nutrients. Mycorrhizal epidermal cell infection levels of 15% to 20% were maintained in the roots in soil medium but decreased to about 5% over the 6 weeks of the experiment in the sand medium. Although M plantlets accumulated more Al in their roots, Al was readily transported to the leaf tissues of M and NM plantlets.
Relationship between Static Headspace and Vapor Concentration Above Dilute Liquid Solution Methods In the Measurement of Volatile Compounds
Authors: Silva S.M. , Beaudry R.M.
Published: February 2019

The generation of dilute vapor phase standards using the static headspace method can be challenging, requiring the construction of specialized chambers or use special methods for adding minute amounts of the compound of interest. The vapor concentration above a dilute water solution can be effective and accurate and has been used to create standards to measure the concentration for a wide range of volatile and semivolatile organic compounds. Such systems are highly temperature-sensitive, however. The goal of this work is to mathematically describe the relationship between vapor concentration above a dilute water mixture for compounds important to postharvest physiology, such as ethanol, acetaldehyde, ethyl acetate, and hexanol. The experiments were carried out in the range of 0 to 40°C and concentration of 0 to 1000 ppm for each compound. Three replications were used for each data point. The concentration was measured after thermal and chemical equilibration by gas chromatography containing a HAYESSEP-N column, by injecting 1 cc of the vapor headspace, using a 8-cm-long needle Hamilton syringe. Relationships for each of the compounds noted were successfully described employing multiple-order equations. For example, the relationship for ethanol vapor concentration was: Y = 12.12356 + 0.9461594*X + 0.5761110e-01*X2 + 0.6565694E-03*X3 + 0.23499598E-04*X4 (R2 = 1.000), with X being the temperature in °C. The relationships described for those compounds provides an useful tool that allows us to dilute liquid standards across a range of temperatures.
Nuclear Magnetic Resonance Imaging Detects Internal Defects in Potatoes
Authors: Wang P.C. , Wang C.Y. , Song H.F. , Yan Z.J.
Published: February 2019

Potatoes with hollow heart or brown center are considered to be of poor quality for both fresh and processing markets. A reliable nondestructive method, which can distinguish affected and normal potatoes, is described here. A Varian 4.7 Tesla, 33-cm horizontal-bore spectroscopy/imaging system was used to obtain nuclear magnetic resonance (NMR) images of potatoes. A two-dimensional multi-slice spin-echo imaging technique was used to acquire the cross-sectional images along the longitudinal direction. The echo time was 35 msec and the repetition time was 1.2 sec. A total of 13 slice images were taken for each potato. A one-dimensional projection technique was also performed to evaluate the possibility of using fast-scan method. The brown center showed high intensity in long echo scans due to its longer TL relaxation time. A suberin-like layer resembling the periderm developed on the cavity wall of hollow heart causing a tan or dark brown coloration. This cavity wall also appeared in high intensity on the image. The affected potatoes can easily be sorted out using this nondestructive NMR imaging technique.
Evaluation of the Organic and Mineral Fertilization on Postharvest Quality of Cantaloupe (Cucumis melo L.)
Authors: Pérez de C Maria E. , Rodirguez Josefina , Torcates Susana , Ramírez Mario Pérez y Hugo
Published: February 2019

Several postharvest quality parameters of cantaloupe fruit were grown under different organic and mineral fertilization schemes We evaluated a Laguna hybrid (Asgrow) cantaloupe grown under a design of blocks completely randomized, with three fertilizer treatments corresponding to: T1, goat manure; T2, simple fertilization; T3 mixed fertilization, with six replications each. The fruits were mature-harvested and stored in a room with an average temperature of 18°C for posterior laboratory analysis. The results showed different effects of the treatments on the following parameters: total soluble solids, diameter of the fruits, and thickness of the pulp, and showed no effects on consistency of fruits, cavity, dry matter, and fresh weight. All these parameters decreased during the period of storage. The organic manure treatments showed the best values of most of the evaluated parameters.
Phytochrome Regulation of Photosynthate Partitioning in Watermelon Plants Exposed to End-of-day Light Treatments
Authors: Ranwala N.K. Damayanthi , Decoteau D.R. , Fernandez R.T.
Published: February 2019

End-of-day (EOD) light treatments were used to study phytochrome involvement in photosynthesis and photosynthate partitioning in watermelon plants. Two-week-old plants were treated with brief low-intensity red (R) or far-red (FR) light for 9 days at the end of daily light period. Petiole elongation in the first two leaves was the first significant growth change in FR-treated plants compared to other plants after 3 days of treatments. This petiole elongation was accompanied by significantly higher photosynthate partitioning to petioles, even without increase in above-ground dry weight of plants. Net CO2 assimilation rate in the second leaf was significantly higher in FR treated plants on a weight basis after 3 days of treatments. Far-red-treated plants had lower chlorophyll content per leaf area and higher stem specific weight compared to R-treated plants after 3 and 6 days of treatments, respectively. Transpiration and stomatal conduction were higher in FR-treated plants compared to other treatments after 3 days of treatments. The EOD FR regulated growth and photosynthate partitioning patterns were reversible when FR treated plants were immediately followed by R. This implies EOD R: FR ratio acting through the phytochrome regulates the growth and development processes in watermelon plants.
Edina Goes Green: A Community Education Project in Low-Input Lawn Care
Authors: Carpenter Perrin J. , Meyer Mary H.
Published: February 2019

The objectives of the project were to design and implement an educational campaign on low-input lawn care, measure its effectiveness, and use the information gained to develop a model education plan that other communities could use. Residents of Edina, Minn., a suburb of Minneapolis, initiated the project by expressing an interest in reducing the amounts of chemical inputs (fertilizers and pesticides) used on residential lawns. The program's educational goal focused on teaching Edina's residents about proper timing and rate of application of all lawn inputs, as well as cultural techniques for producing a healthy lawn. The educational campaign consisted of informational articles published in Edina's quarterly community magazine; the establishment of 19 demonstration sites in which volunteer homeowners worked with Master Gardener mentors learning low-input lawn care techniques; a WWW page where information about lawn care and the project itself was posted; and a public seminar conducted by a turf specialist. Two surveys (May 1996 and April 1997) were distributed, each to a random sample of 800 Edina residents. The surveys measured lawn care knowledge and current practices, attitudes concerning pesticide use and the environment, as well as the effectiveness of this educational program. Recommendations for other community educational programs will be presented.