bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes of Orchard Soil Property and Fruit Quality of `Fuji' Apples Treated with Energized “Bio-green Water”
Authors: Kim Woo Soo , Kim Hee Jung , Kim Seong Bong
Published: February 2019

The energized water, Bio-Green Water (B.G. Water) was manufactured through a series of processes: water purification → adding catalysts → exposure with special energy spectra → filtering, by Kyungwon Enterprise Co. B.G. Water was treated with irrigation of 4 liters/tree at 30 Apr. 1994 and 8 liters/tree at 20 June 1994 in the `Fuji' apple orchard soil, and a pasting to the trunk of apple trees at 20 Apr. 1994. In terms of orchard soil property, Ca and Mg contents were outstandingly increased; however, P2O5 was decreased and K2O was not influenced by irrigation of B.G. Water. The B.G. Water treatment changed soil pH from 4.71 to 5.81 of surface soil level (0 to 20 cm) and from 4.82 to 6.45 of deeper soil level (30 to 50 cm). B.G. Water treatment showed higher soluble solids in apple fruit juice, and lower flesh browning after peeling than that of control. Of mineral contents in fruit skin, Ca was increased; however, N was decreased by the B.G. Water treatment. Of the four solvents fraction for Ca extraction, water-soluble Ca content was increased in the fruit skin treated with B.G. Water, whereas the contents of N, P, Ca, Zn, and B were decreased in the leaves and stem bark of apple trees treated with B.G. Water.
Irrigation Management Affects Soil Solution NO3-N Concentration
Authors: Neilsen Denise , Neilsen Gerry H. , Parchomchuk Peter , Hogue Eugene J.
Published: February 2019

Direct application of fertilizers in irrigation water (fertigation) has been advocated as an efficient method of fertilizing fruit trees. However, more information is needed on the relationship between irrigation and N inputs in order to target fertigation to meet plant demands. Soil solution NO3-N concentration was measured at three sites in response to the method of fertilizer application in which 25 g N/tree per year was either spring-broadcast with sprinkler irrigation or fertigated at 8 weekly intervals through drip irrigation; the amount of irrigation water in which 50 g N/tree per year was given in 63 daily fertigations with either 4 or 8 liters of water/day for two soil types and the concentration of fertigated N in which either 75 or 150 ppm NO3-N was given in 63 daily fertigations. Soil solution NO3-N concentration decreased rapidly for broadcast fertilizer with sprinkler irrigation and was lower than for weekly fertigation with drip irrigation. Doubling the amount of irrigation water effectively halved the soil solution NO3-N concentration in both the silt loam and loamy sand soils, although concentrations were higher in the silt loam soil. Movement of applied N below the root zone was halted for the silt loam soil by mid-summer with the lower amount of irrigation water, but was only delayed in the loamy sand soil. Doubling the average concentration of N in the irrigation water resulted in a doubling of the concentration of NO3-N in the root zone. A simple model was devised to predict the soil solution NO3-N concentration based on N and water inputs and fitted to measured values for daily and weekly fertigation.
Bark storage Protein in Peach, Plum, and Cherry Trees
Authors: Bañados M.P. , Santiago M.S. , Eterovic C.
Published: February 2019

The main form of nitrogen reserves during overwintering are amino acids and proteins. Specific proteins called bark storage proteins (BSP) have been characterized in many tree species. To identify BSPs in `O'Henry' peach, `Angeleno' plum, and `Early Burlat' cherry trees, samples of bark were collected from January through December 1993 from trees growing under field conditions in Santiago, Chile. SDS-PAGE analyses were used to characterize the seasonal variation on the protein pattern on the bark of those Prunus species. A 60 kDa BSP was identified in the bark of all three species, which corresponds to the main protein present in the bark during the winter. This protein may play an important role as a nitrogen reserve in these fruit trees.
Use of Forcing Solution Techniques to Improve Chestnut Micropropagation
Authors: Yang Guochen , Read Paul E. , Kamp-Glass Marihelen
Published: February 2019

Chestnut (Castanea spp.) is considered difficult to micropropagate. The timing for harvesting explant materials from forced stems is critical, although many factors need to be considered for successful micropropagation. Previous research with spirea and five-leaf aralia demonstrated that forcing solution techniques extended the availability of high-quality explant material, thus expediting micropropagation. However, preliminary research illustrated that chestnut is very difficult to force and the new forced softwood growth is very short-lived, which made micropropagation difficult. It was found that, at about 7 days from budbreak, the forced chestnut softwood growth (about 2 cm long) served as the best explant material. If longer than this timing window, the new growth would die. If shorter, the explants had a high contamination rate, exudation of purported phenolic compounds, and explants would not regenerate. Shoot proliferation and callus regeneration were achieved by culturing good-quality explants on Woody Plant Medium supplemented with 0.1 mg BA/liter. The new shoots grew vigorously in vitro with apparent normal morphology.
Factors Essential for the Success of a Master Gardener Demonstration Garden
Authors: Stack Lois Berg , Gray Gleason
Published: February 2019

Penobscot Co. (ME) Master Gardeners initiated a highly successful demonstration garden in 1994, on the university's sustainable agriculture farm. Five factors for the garden's success are suggested for consideration by groups planning similar projects: 1) The garden has a permanent site with excellent road visibility, on a public farm that supports public service; 2) The farm manager tills the plot and manages cover crops; 3) 10 to 12 Master Gardeners and two extension educators commit significant ongoing labor to the project; 4) Local businesses supply plants and other materials; 5) A vital statewide Master Gardener Program assures an ongoing supply of volunteers, ideas and enthusiasm.
Phasic Control of Photosynthetic Photon Flux for Lettuce Production in CELSS
Authors: Chun C. , Mitchell C.A.
Published: February 2019

For biomass production in a space-deployed Controlled Ecological Life-Support System (CELSS), efficient usage of limited resources such as light, CO2, growth area, and labor is more consequential than for biomass production on Earth. Light will be one of the most energy-consuming environmental factors to provide in CELSS. Therefore, development of an energy-efficient lighting-control strategy would make a great contribution to the sustainability of CELSS. Lettuce (Latuca sativa L.) was used as a model salad crop for the development of new control methods due to its rapid growth rate and high harvest index (≥80%). Lettuce seeds were sown and plants were cultured hydroponically in the Minitron II plant growth/canopy gas-exchange system. Canopy net photosynthetic rates (μmol CO2/m2 per s) were measured under a specific photosynthetic photon flux (PPF) and analyzed to decide the PPF of the next 1-h interval. Appropriate PPFs were provided on the initial day and during the first 1-h interval of each 20-h photoperiod. Plant-growth indices, crop yield rates (g/m2 per day), and power consumption rates were determined for different lighting strategies to identify the best compromise between energy cost and yield. Day/night temperature and CO2 concentration were maintained at 25/25C and 1100/400 μl·liter–1, respectively. This research is supported by NASA grant NAGW-2329.
Using Spoke Wheel Injectors for Improved N Use Efficiency in Dry Bulb Onions
Authors: Fritz Vincent A. , Rosen Carl J.
Published: February 2019

Recent adoption of a raised bed production system for improved drainage on muck soils prompted experimentation to improve N use efficiency. The established methods of N fertilization was to simply broadcast 908 kg·ha–1 of 10–26–27 prior to planting in single rows. The raised bed production system results in a concentrated rooting zone directly underneath the raised bed. A system that places the N fertilizer within the root zone of influence at a peak time of crop utilization would increase N use efficiency, reduce fertilizer costs, and promote appropriate environmental stewardship. The use of a spoke wheel injector to sidedress N fertilizer effectively reduced total fertilizer costs by half, while producing onion yields equal to or greater than the established broadcast method under the raised bed production system. In addition, the use of the spoke wheel injector was not intrusive to the integrity of the raised bed, which allowed realization of benefits from using raised beds for the entire growing season.
Tomato Petiole Sap Nitrogen and Potassium Seasonal Trends with Various Fertilization Programs
Authors: Hochmuth G.J. , Locascio S.J. , Rhoades F.M. , Olson S.M. , Hanlon E.A.
Published: February 2019

Tomato (Lycopersicon esculentum Mill.) was grown on fine sand and fine sandy loam soils at two sites to evaluate effects of N and K fertilization practices on petiole fresh sap N and K concentrations and to determine N and K sufficiency ranges. Treatments included applying N (196 kg·ha–1) and K (112 kg·ha–1) either 0%, 40%, or 100% preplant. With 0% or 40% preplant treatments, the remaining N and K was injected through the drip irrigation system in six or 12 equal weekly amounts or by a variable injection rate with most of the N and K injected between weeks 5 and 10 of the season. Petiole sap K concentration declined during the season, but was not greatly affected by treatment. Petiole N decreased over the season from 1100 to 200 mg NO3-N/liter and decrease was greater for preplant N treatments. Petiole N was correlated with tomato yield, especially for petiole N measured in the period of 5 to 10 weeks after transplanting.
Potential for Noninfectious Bud-failure in `Carmel' Almond Orchards in California
Authors: Kester Dale E. , Shackel K.H , Gradziel T.M. , Viveros M. , Micke W.C.
Published: February 2019

The potential for noninfectious bud-failure in propagation source material for `Carmel' almond in California has been determined in progeny tests from commercial nursery sources. Percentage BF increased with time (temporal), but decreased in severity (spatial). Analysis of variability in nursery sources showed that the key to successful selection for low BF potential is the individual tree, although variability exists among nurseries, budsticks (within trees), and individual buds (within budsticks). One-half of the individual trees of the nursery population tested have produced BF progeny so far within the test period. Future BF from the remainder was project by a BF model to be beyond the critical economic threshold. Two low BF-potential single tree sources were identified for commercial usage and progeny tests have started on an additional 19.
Heritability, Genetic, and Phenotypic Correlations of Several Peach Traits
Authors: de Souza Valdomiro A.B. , Byrne David H. , Taylor Jeremy F.
Published: February 2019

Heritability estimates are useful to predict genetic progress among offspring when the parents are selected on their performance, but they also provide information about major changes in the amount and nature of genetic variability through generations. Genetic and phenotypic correlations, on the other hand, are useful for better planning of selection programs. In this research, seedlings of 39 families resulting from crosses among 27 peach [Prunus persica (L.) Batsch] cultivars and selections were evaluated for date of full bloom (DFB), date of ripening (DR), fruit period development (FDP), flower density (FD), node density (ND), fruit density (FRD), fruit weight (WT), soluble solids content (SS), apical protuberance (TIP), red skin color (BLUSH), and shape (SH) in 1993 and 1994. The data were analyzed using the mixed linear model. The best linear unbiased prediction (BLUP) was used to estimate fixed effects and predict breeding values (BV). Restricted maximum likelihood (REML) was used to estimate variance components, and a multiple-trait model to estimate genetic and phenotypic covariances between traits. The data indicates high heritability for DFB, DR, FDP, and BLUSH, intermediate heritability for WT, TIP, and SH, and low heritability for FD, ND, FRD, and SS. They also indicate year effect as a major environmental component affecting seedling performance. High correlation estimates were found between some traits, but further analysis is needed to determine their significance.
Influence of Fertilizer Rregime on Leaf Chlorosis/Necrosis of Two Varieties of Chrysanthemum
Authors: Reyes Trinidad , Nell Terril A. , Barrett James E.
Published: February 2019

`Tara' and `Boaldi' were fertilized with 150 and 450 ppm from 20N–4.7P–16.6K soluble fertilizer and moved at flowering to postproduction conditions (21 ± 2C and 10 μmol·m–2·s–1). Shipping was simulated for 1 week at 26C. `Tara' exhibited burned leaf margins (necrosis) and chlorosis following shipping. At 150 ppm, leaves had brown, dried margins, but the damage did not progress indoors. Necrosis was worse at 450 ppm. Leaf chlorosis/necrosis of non-shipped plants at the 450 fertilizer level did not appear until the 3rd week indoors. At experiment termination, no leaf damage occurred in non-shipped `Tara' or `Boaldi' with 150 ppm. `Boaldi' did not show damage after shipping regardless of the treatment but symptoms (necrosis and wilting of leaves) evolved during the first 2 weeks indoors on plants fertilized with 450 ppm. A 50% reduction in root soluble carbohydrates was found at the highest fertilizer rate at flowering, suggesting that leaf chlorosis/necrosis is related to carbohydrate depletion in chrysanthemum.
Persistence and Replacement of Preplant Fertilizers from Highly Leached Peat-based Root Media
Authors: Biernbaum John A. , Argo William R. , Weesies Brian , Weesies Allen , Haack Karen
Published: February 2019

A series of experiments was conducted to quantify the rate of nutrient loss from a container medium in a 15-cm-wide (1.3-liter) pot with a container capacity (CC) of 0.7 liter/pot under mist propagation and to determine the effectiveness of reapplying fertilizer to medium at 90% of CC with either top watering or subirrigation. Reducing the volume of water applied per day decreased the rate of nutrient leaching. Based on CC leached (CCL), the rate of nutrient loss was similar for all treatments. Differences in the rate of macronutrient removal from the media were measured, but, by 2 CCL, the concentration of all nutrients tested was below acceptable levels for the saturated media extract. With top watering, reapplying water-soluble fertilizer (WSF) at volumes under 0.2 liter/pot did not affect the nutrient concentration in the lower half of the pot at WSF concentrations up to 86 mol N/m3. Applying up to 0.8 liter/pot did increase nutrient concentrations in the lower half of the pot, but the media nutrient concentrations were lower than that of the applied WSF concentration. Applying WSF with subirrigation was limited by the moisture content of the media prior to the irrigation.
`Empire' Apple Responses to Fruit-thinning Chemicals
Authors: Stiles Warren C.
Published: February 2019

Effects of NAA at 5, 10, and 15 ppm, Accel at 50, 75, and 100 ppm, NAA at 7.5 ppm plus carbaryl at 600 ppm, and a nontreated control on fruit set, fruit size, length–diameter ratio, seed numbers per fruit, and total yield of fruit were evaluated during the 1994 season. All treatments were applied to 10-year-old `Empire'/M.9/MM.111 trees as dilute sprays at a rate of 935 liters·ha–1 with an airblast sprayer on 3 June. King fruit measured 9–11 mm in diameter at time of application. Fruit set (fruits per 100 blossom clusters) was reduced significantly by Accel at 50 ppm (17%) and by NAA plus carbaryl (26%) in comparison with the nontreated control. Total yield of fruit was increased by all treatments; however, fruit from trees treated with NAA plus carbaryl was significantly larger than that from all other treatments. Percentages of small fruit, <108 g, were reduced by all treatments. Percentage of fruit ≥ 153 g was increased significantly only by NAA plus carbaryl. Length–diameter ratios and numbers of fully developed seeds per fruit were not influenced significantly by treatments. NAA at rates of 5, 10, and 15 ppm, or Accel at 50, 75, or 100 ppm, were less effective than a combination of NAA at 7.5 ppm plus carbaryl at 600 ppm in reducing fruit set and in affecting fruit size or fruit size distribution.
Response of Several Apple Cultivars to Thinning Sprays of Benzyladenine, NAA, Carbaryl, and Combinations Thereof
Authors: Dennis F.G.
Published: February 2019

In 1994, benzyladenine (BA, formulated as Accel, containing 1.8% BA and 0.18% GA4+7) was evaluated as an apple fruit-thinning agent. Naphthaleneacetic acid (NAA, 10 ppm) and carbaryl (60 g·liter–1) were also used, as well as combinations of these chemicals with BA. Whole trees were treated with either an airblast sprayer or a hand gun, BA being used at 15–20 g/acre. Good responses to BA were obtained in one of two trials, with both `Empire' and `Gala', but `Jonagold' and `Jonathan' were not responsive (one trial each). In general, response to NAA and carbaryl was more consistent. In only one orchard (`Gala') did BA appear to increase fruit size without reducing crop load. Combinations of BA with NAA or carbaryl were generally no more effective than one chemical alone, but such combinations overthinned in one experiment with `Empire'.
Pest Resistance in Redbud
Authors: Eigenbrode Sanford , Tipton Jimmy
Published: February 2019

Mexican redbud (Cercis canadensis var. mexicana) exhibits resistance to leaf cutter bees (Megachile spp., LCB). Resistant trees (CMG) have glossy leaves and sustain little LCB damage as compared to dull-leaf Mexican redbud (CMD) and the closely related eastern redbud (Cercis canadensis, CC). On average, LCB made 35 times as many cuts per week on CC as on CMG and CMD, even though there were half as many leaves available. Mexican redbud leaves are twice as thick as CC leaves, which may account for LCB preference for the latter. However, leaves from CMG and CMD are similar in leaf thickness, cuticle wax content, and resistance to penetration, yet LCB had an even stronger preference for the former. More than 83 times as many cuts per week were made on CMD over CMG, even though the number of leaves was comparable. CMG leaves have a thicker cuticle on the upper surface that lacks wax crystals present in the CMD and CC. The upper cuticle from CMG leaves also contains fewer lipids and an altered lipid composition (notably fewer long-chain alcohols) compared to CMD.
Role of Endogenous Allelochemicals in Host Plant Resistance to Japanese Beetles
Authors: Ranney Thomas G. , Burton James D. , Walgenbach James F. , Pharr D. Mason , Patton Cindy A. , Maness Eleanor P.
Published: February 2019

No-choice feeding trials were conducted with adult Japanese beetles on leaves from 14 taxa of rosaceous trees. Feeding intensity (leaf area consumption) ranged from 0.08 to 6.1 cm2/day for Prunus virginiana and P. sargentii, respectively. Analysis of endogenous chemical constituents suggested that the mechanisms of resistance varied for the different plant genera. Among the Prunus taxa there was a significant negative correlation between cyanide potential and feeding intensity (r = –0.56). Tissue toughness (resistance to tearing) was also negatively correlated with feeding intensity (r = –0.39) for all taxa. Soluble sugars (glucose, fructose, sucrose, and sorbitol) had no significant phagostimulatory effect, separately or in combination.
Effects of Various Nitrate: Ammonium Ratios on Sweetpotato Growth
Authors: David P.P. , Trotman A.A. , Mortley D.G. , Douglas D. , Seminara J.
Published: February 2019

A study was initiated in the greenhouse to examine the effects of five \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{+}:\mathrm{NO}_{3}^{-}\) \end{document} ratios on sweetpotato growth. Plants were grown from vine cuttings of 15-cm length, planted in 0.15 x 0.15 x 1.2-m growth channels using a closed nutrient film technique system. Nutrient was supplied in a modified half-strength Hoagland's solution with a 1:2:4 N:K ratio. \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{+}:\mathrm{NO}_{3}^{-}\) \end{document} ratios investigated were 100:0, 0:100, 40:60, 60:40, and a control that consisted of a modified half-Hoagland solution with an N:K ratio of 1:2:4 and an \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{+}:\mathrm{NO}_{3}^{-}\) \end{document} of 1:7. Treatments were initiated 30 days after planting (DAP). Sequential plant harvest began 30 DAP and continued at 30-day intervals until final harvest at 150 DAP. Results showed a linear increase in fresh storage root fresh weight until 90 DAP for all treatments. However, from 60 DAP until the end of the growing season, plants grown in a 100% \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{+}\) \end{document} solution consistently produced significantly less storage roots than in all other treatments. While all other treatments showed a decrease in storage root fresh weight after 90 DAP, plants grown in 100% \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NO}_{3}^{-}\) \end{document} and the control solution continued to increase linearly in storage root production. Storage root dry weight throughout the growing season followed similar trends to that of storage root fresh weight. Data suggest that a nutrient solution containing NO–3as its sole nitrogen source may be adequate for sweetpotato growth. This would make it possible for utilizing a one-way pH control method for nutrient solution.
Response of Desert Lettuce to Controlled-release N Fertilizer
Authors: Sanchez C.A.
Published: February 2019

Lettuce produced in the desert typically shows large yield responses to N fertilization. However, concern about the potential threat of nitrate-N to ground-water has prompted additional studies aimed at developing improved N management practices. Field experiments were conducted between 1992 and 1995 to evaluate the response of crisphead lettuce to controlled-release N fertilizer (CRN). The use of CRN was compared to a soluble N fertilizer applied preplant (PP), and a soluble N fertilizer applied in split-sidedress applications (SD). Rates of N fertilizer application ranged from 0 to 300 kg·ha–1. Lettuce generally showed significant responses to N rate and N management practice. However, response to management practice varied by site-season. When conditions for N loss were high, SD and CRN management strategies were superior. However, in other site-seasons, SD management sometimes resulted in inferior head quality and marketable yield when compared to other management strategies. Data averaged over six site-seasons shoed improved yield and quality to CRN management strategies compared to PP and SD strategies.
Selection of the Best Pollinizer for Late-flowering Almond Varieties
Authors: Talaei Ali Reza , Imani Ali
Published: February 2019

In order to select the best pollinizer for late-flowering varieties of Azar (A.H.50), Shokoufeh (AH.3) Sahand (L-62), and Feragues, a range of studies were carried out at Azar-Shahr Horticultural Research Station (Tabriz, Iran) and actions undertaken for introduction of the best pollinizers for these varieties under both laboratory and orchard conditions by a Dactroil Statistical Plan with a completely random base plan. Seven types of pollens from Shokoufes (AH.3), Azar (A.H.50), Sahand (L-62), Ferragnos (Fer), Neplus Ultra (N.P.U.), None Paril (N.P.), and Harir (A.H.25) were selected and the pollen prepared. Pollen was collected from the experimental grounds. Hand-pollination was repeated in three stages for 3 days. Honeybees and other insects were controlled before and after artificial pollination to not interfere with the experiment. Percent fruiting was recorded twice 1 month after pollination (1 June) and again 1 July and analyzed statistically. Average fruiting for female flowers (pollen receivers) was from 0% to 47%. Thus, all varieties could not produce fruit (control). Average fruiting from other pollens with different ratios were significant from 1% to 5%. The almond varieties Azar, Shokoufeh, Sahand, and Ferragnos are self-incompatible and there is no need to emasculate pollen in pollination programs. However, Azar and Harir are incompatible with each other. Pollination efficiency of late-flowering almond varieties depends on the pollinizers and the compatibility with the cultivars, provided that pollination is carried out only by insects, particularly honeybees. The effect of wind on pollination in our almond orchards appeared to be insignificant.
Accumulation and Partitioning of Dry Matter in Fruiting and Nonfruiting Pineapple Plants
Authors: Marler Thomas E. , Lawton Patrick D.
Published: February 2019

`Smooth Cayenne' pineapple plants were propagated from suckers of uniform size. The plants were grown in containers, and a large percentage of them naturally flowered in synchrony at 13 months. This provided an opportunity to study the accumulation and partitioning of dry matter in fruiting and nonfruiting plants of uniform age. Six plants with or without fruit were harvested when the syncarps developed color. Plants and fruit were separated into crown, syncarp, slips, peduncle, leaves, stems, and roots. Plants without fruit were separated into leaves, stem, and roots. There were no suckers, and the stem was divided at the ground level. Leaves were counted and all tissue was dried to a constant weight. Total dry matter accumulation and the ratio of below- to above-ground dry matter was not different between the two groups of plants. The plants were similar in size and leaf number at the time of flowering, but the number of leaves was fixed at that time in the plants with fruit. As a result, plants that did not flower had about twice as many leaves as the plants with fruit at the termination of the study. Thus, the vegetative growth of continued at a rate similar to that of the reproductive structures of the plants that did flower.
Municipal Solid Waste Compost and Fertigation Frequency on Growth of Potted Poinsettia
Authors: Ku Catherine S.M. , Bouwkamp John C. , Gouin Frank R.
Published: February 2019

Municipal solid waste (MSW) may be a potential substitute for peat substrate in soilless medium. Adequate N and P are needed for a complete composting of MSW. MSW piles treated with diammonium phosphate (MSWP) or without P on Mar. 1994 were cured for 5 months. In Fall 1994, a factorial treatment combination of nine mixes and 3 fertigation treatments were evaluated in a completely randomized design on soft-pinched, single-stem `Red Sail' poinsettia. Mixes were MSW or MSWP ranging from 33% to 100% by volume in 1 peat: 1 perlite (v/v) and Sunshine mix was used as the control. Fertigation treatment began on the 1st, 2nd, or 3rd week after potting. Fertigation solution contained 266 mg·liter–1 N from 30N–4.4P–8.8K. The total fertigations ranged from eight to 10 for the 13-week study. With MSW mixes, shoot dry mass at the week 1 fertigation was 36% larger than at the week 3 fertigation. At the week 3 fertigation, shoot dry mass with 100% MSWP was ≈53% greater than with the 100% MSW. Shoot dry mass with 100% MSWP was similar to the control at the week 1 fertigation.
Seed Coat Permeability Influences Sinapine Leakage from Non-germinable Brassica Seeds
Authors: Lee P.C. , Taylor A.G. , Min T.G.
Published: February 2019

Sinapine leakage to detect seed germination potential on a single-seed basis in Brassica has been developed as a rapid test. In this test, sinapine leakage predicts that a seed is non-germinable; however, the major source of errors in this method are false-negative (F–)—i.e., the method predicted a seed was germinable because the seed did not leak, and it did not germinate. The sinapine leakage index (SLI) was used to asses the F– for any seed lot by dividing the number of non-germinable seeds that leaked sinapine by the total number of non-germinable seeds. Seed lots including cabbage, cauliflower, and broccoli (B. oleracea L., Captitata, Botrytis, and Italica groups, respectively) were used to examine the F–. The leakage rate as measured by T50, the time for 50% of heat-killed seeds to leak, was linearly correlated to SLI. Cabbage seeds were viewed by scanning electronic microscopy and leaking non-germinable seeds either had cracks or were shrunken. NaOCl pretreatment has been found to increase the rate of sinapine leakage and SLI. The mode of NaOCl was due to high pH altering the seed coat permeability. Chemical analysis was conducted on isolated seed coats for pectin, tannins, hemicellulose, cellulose, phenolic lignin, and cutin. It was found that the higher SLI (more permeable) lots contained lower amounts of cutin, suggesting that cutin may restrict the diffusion of sinapine through the testa.
`Florida Calypso': A Multicolored Caladium for the Landscape and Containers
Authors: Wilfret Gary J.
Published: February 2019

Caladiums, grown for the colorful foliage in containers and the landscape, are the major floricultural tuber crop grown in Florida. They are planted for their variety of leaf colors, shapes, color patterns, and their ability to grow in areas of reduced light and high temperatures. `Florida Calypso' (FC), a fancy leaf caladium with dark-red central venation and rose and white blotches, was released by the Univ. of Florida in 1995. It is in the same color classification as `Carolyn Whorton' (CW), a top-selling rose/pink cultivar. When grown with on de-eyed 6.5-cm-diameter tuber per 10-cm pot, FC was 33 cm tall, produced five leaves within 33.4 days from planting, and had 33.6 leaves after 8 weeks, compared to 42.9 cm, 48.2 days, and 11.0 leaves, respectively, of CW. When grown in the field for tuber production, FC produced larger tubers, had a greater total tuber yield by weight, and had a higher production index than CW. Tuber yields of FC were not significantly different than `Candidum', the cultivar produced most in Florida. `Florida Calypso' can be grown in heavily shaded areas or in full sun in the landscape and in 10- to 40-cm containers.
Colchicine-induced Amphidiploids of Rose Interspecific Hybrids
Authors: Ma Yan , Byrne David H. , Chen Jing
Published: February 2019

An objective of our rose breeding research is to transfer resistance to blackspot and other diseases from wild diploid species to modern rose cultivars. Interspecific hybrids among blackspot-resistant diploid species were chosen for chromosome doubling to produce fertile amphidiploids that could be hybridized to the tetraploid commercial germplasm. Five such F1 interspecific hybrids were treated with colchicine. The study included two different application procedures (shake in colchicine solution or colchicine in media), four colchicine concentrations (0.05%, 0.1%, 0.15%, and 0.20%), and five treatment periods (1, 3, 5, 8, and 10 days). After colchicine treatment, all the materials were cultured in vitro. One thousand-thirty-seven surviving explants were selected for typical “gigas” characteristics of doubled diploids. Chromosome counts on shoot tips of these selected genotypes confirmed 15 amphidiploids. The best colchicine treatment varied among the interspecific hybrids. Higher colchicine concentrations or duration reduced growth rating, rooting, and percent survival. The recognition of amphiploids and ploidy chimeras from young seedlings will also be discussed.
Changes in Water Relation Parameters in Leaves of Olive (Olea europaea L.) during Salinity Stress and Relief
Authors: Gucci Riccardo , Lombardini Leonardo , Tattini Massimiliano
Published: February 2019

Water relation parameters were calculated from analysis of 92 pressure-volume isotherms of leaves of two olive varieties, `Leccino' and `Frantoio', measured after 4 weeks of salinity stress and 4 weeks of subsequent relief either in hydroponics or soil culture. `Frantoio' was more salt-tolerant than `Leccino', but no major differences in water relation parameters emerged between the two varieties. Increasing salinity from 0 to 200 mM NaCl decreased predawn leaf water potential from –0.5 MPa to –1.3 MPa, relative water content (RWC) from 97.6% to 89%, and leaf osmotic potential (Ψπ) from –2.0 to –3.5 MPa. Relative water content at turgor loss point (RWCtlp) was decreased from 89% to 85% (soil culture) and from 86% to 80% (hydroponic culture) in 0 to 200 mM CaCl-treated plants, respectively; a lower RWCtlp was also retained during the relief from salinity. Active osmotic adjustments induced by salinity was the result of accumulation of both inorganic ions and compatible solutes (e.g., mannitol). Maintenance of lower Ψπ and RWCtlp during relief indicated that salinized plants were better adapted to withstand further stress and that this potential might be exploited to harden olive plants to be used in arid or saline environments.
Nitrogen Leaching, Water, and Nitrogen Use Efficiency of Citrus Trees Fertilized at Three Rates of Nitrogen
Authors: Syvertsen Jim , Smith M.L.
Published: February 2019

Effects of nitrogen (N) rate and rootstock on tree growth, fruit yield, evapotranspiration, N uptake, and N leaching were measured over a 2-year period. Four-year-old `Redblush' grapefruit trees on either sour orange (SO), a relatively slow-growing rootstock, or `Volkamer' lemon (VL), a more-vigorous rootstock, were transplanted into 7.9-m3 drainage lysimeter tanks filled with native sand and fertilized at three N rates. N rates averaged from about 14% to 136% of the recommended rate when trees were 5 and 6 years old. More N leached below trees on SO as trees on VL had greater N uptake efficiency. Canopy volume and leaf N concentration increased with N rate, but rootstock had no effect on leaf N. Fruit yield of trees on SO was not affected by N rate, but high N increased water use and yield for larger trees on VL. Canopy growth or yield per volume of water used (water use efficiency) was lowest at low N, but N use efficiency was highest at the low N rates.
Leaf Gas-exchange and Ion Content of Papaya Plants Simultaneously Exposed to Salinity and Flooding
Authors: Marler Thomas E.
Published: February 2019

A container study and a hydroponics study were conducted to determine gas-exchange and ion content of `Cariflora' papaya plants as influenced by a combination of salinity and flooding. Plants grown in nutrient solution were subjected to 1 or 8 dS·m–1 as salinity treatments and 6.54, 3.62, or 0.92 mg oxygen/liter as the flooding treatments. Plants in the container study were subjected to 0, 4, or 8 dS·m–1 as salinity treatments, and half of the plants in each salinity level were flooded. Leaf gas-exchange began to decline by day 1 in all plants receiving flooding, and was zero by day 5. In contrast, gas-exchange of plants experiencing salinity began a slow decline after 5 to 7 days. Stomatal conductance of salinized plants was 25% to 33% of the control plants in the container study after 39 days. No interaction occurred between flooding and salinity treatments since the stomatal response to flooding was so rapid across all levels of salinity. Roots and stems played a major role in storing Na+ and Cl– in salinized plants. For example, stems contained more than two times the dry weight concentration of both ions as did leaves. Older leaves accumulated more Na+ and Cl– than did younger leaves. Flooding decreased Na+ and Cl– accumulation in roots, stems, and leaves in all salinized plants.
Effect of Root Zone Temperature on the Mineral Composition of Xylem Sap and Plasma Membrane K+–Mg++–ATPase Activity of Grafted Cucumber and Figleaf Gourd Root Systems
Authors: Choi Kyong Ju , Chung Gap Chae , Ahn Sung Ju
Published: February 2019

Cucumber (Cucumis sativus L.) seedlings were grafted onto cucumber-(CG) or figleaf gourd (FG, Cucurbita ficifolia Bouche) seedlings in order to determine the effect of solution temperature 12, 22, and 32C) on the mineral composition of xylem sap and plasma membrane K+–Mg++–ATPase activities of the roots. Low solution temperature (12C) lowered the concentration and in xylem sap of CG plants, but not of FG plants. Concentrations of K+, Ca++, and Mg++ in xylem sap were less affected than anions by solution temperature. The plasma membrane of FG plants grown in 12C solution temperature showed the highest K+–Mg++–ATPase activity at all ATP concentrations up to 3 mM and at low reaction temperature up to 12C, indicating resistance of figleaf gourd to low root temperature.
Relationship of Winter Stage of `Concord' Grapevine Buds, Previous Season, and Return Bloom
Authors: Goffinet Martin C. , Welser Mary Jean
Published: February 2019

Overwintering buds and internodes of Vitis labruscana `Concord' were taken from minimal- (MP) and balance-pruned (BP) vines in Dec. 1993 and Dec. 1994 from canes whose weight, crop weight, total nodes, and nodes with periderm were known. Winter characters recorded were: node-5's primary bud basal area, total nodes, and developmental stage of cluster primordia; stage of largest cluster in the secondary bud; vascular area of cane internode 5. Fifty node-5 buds were tagged in each treatment and flower and fruit number per cluster later recorded. Regression analysis showed no effect of a shoot's crop, cane weight, node number, or nodes having periderm on any character measured in the overwintering buds or canes for either treatment. Regression analysis did show mean flower number per cluster was linearly related to mean winter stage per cluster in both treatments, with all values falling on one line. Differences between treatments were one of degree of cluster development; BP vines had more-developed winter and spring clusters and more flowers and fruit per shoot. The slope of the regression was identical the last 3 years, although the y intercept varied each year; thus, a given cluster stage in the overwintering bud was capable of producing a variable number of flowers the next season, depending on year. Flower number per shoot appeared positively related to growing-degree-days the previous season.
Aroma Volatile Production in Preharvest AVG-treated `Golden Delicious' Apple Fruit and the Effect of Poststorage Ethylene Treatment
Authors: Song Jun , Bangerth Fritz
Published: February 2019

Changes in the profile of aroma volatiles during ripening and after ethylene treatment in apple fruit have revealed a close relationship exists between ethylene production and the timing and magnitude of volatile synthesis. Therefore, AVG (ethylene biosynthesis inhibitor) was used to study the relationship between volatile biosynthesis and metabolic processes affected by ethylene in apple fruits. AVG-treated fruit were stored either for 1 month at 2C in air or 5 months in ULO condition. During the post-storage ripening, the fruits were exposed to 50 μl·liter–1 of ethylene at least 12 h/day. Aroma production was determined at 20C. Total volatile compound production by AVG-treated fruit was much lower than that of untreated fruit. A significant increase in the production of most aroma volatile after 1 month storage in air was induced by ethylene treatment to AVG-treated fruits. I was noted that branched-chain volatile, such as 2-methylbutylacetate, which originates from branched-chain amino acids, has increased prior to butylacetate and hexylacetate, which are derived from fatty acids. Ethylene treatment was unable to stimulate the production of straight-chain volatile compounds following the 5 months of ULO storage. These results are consistent with observations suggesting apple fruit lose their sensitivity to ethylene after long ULO storage.
Somatic Embryogenesis using Immature Zygotic Embryos from Developing Fruits of Papaya (Carica papaya)
Authors: Dhir S.K. , Yadava U.L.
Published: February 2019

An efficient protocol has been developed for the in vitro multiplication of papaya (Carica papaya L.) through somatic embryogenesis utilizing immature zgotic embryos. Somatic embryos were initiated on MS basel media supplemented with 5 mg·liter–1 2,4-D, 400 mg·liter–1 glutamine, and 6% sucrose. After culturing for 2 months, 65% of the explants became highly embryogenic. Each explant produced 50 to 80 embryos in 4 months on culture induction medium. Frequency of embryogenesis was increased (75 to 150 somatic embryos on 80% explants) upon supplementing medium with 4% maltose as a carbon source and 100 mg·liter–1 L-asparagine. The embryogenic callus appeared yellow and embryos at different stages of development were well-organized. On regular subculturing, these cultures continued to produce secondary embryos. Following their transfer to the hormone-free medium supplemented with 4% maltose, these embryos germinated. The somatic embryogenesis system is rapid, repetitive, and highly proliferative. Thus, this system may have a potential use in the development of synthetic seed and transgenic papaya plants. Details of important factors affecting somatic embryogenesis will be discussed.
Pruning Method Affects Lowbush Blueberry Yields
Authors: Smagula John M. , Dunham Scott
Published: February 2019

Flail mowing was compared to traditional pruning by oil fire over a 12-year period in two fertility experiments testing interactions with pruning method. In study one (1983–1986), urea at 0, 22.4, 44.8, 67.2, or 89.6 kg·ha–1 was applied preemergent in a split-block design with fertility as the main effect, and pruning method split within six blocks. Study two (1987–1994) continued the pruning and application of fertilizer on the treatment plots with similar rates, but diammonium phosphate (DAP) replaced urea as the fertilizer. Leaf tissue N concentrations were above the 1.6% standard and urea had no effect or decreased yield. There was no interaction of fertility and pruning and no effect of pruning method on yield. No interaction of fertility and pruning was found in study two, but DAP increased leaf P concentrations and yield and, after three cycles of mowing, yields had begun to decline in mowed plots compared to burned plots. No meaningful differences in leaf nutrient concentrations were found between plants in mowed and burned plots.
Temperature Influences Yield, Leaf Expansion and Unfolding, and Vine Growth of Sweetpotatoes Grown in NFT
Authors: Mortley Desmond G. , Loretan P.A. , Bonsi C.K. , Hill W.A.
Published: February 2019

Growth chamber studies were conducted to evaluate the effect of four diurnal temperatures (24/18C, 26/20C, 28/22C, and 30/24C) on yield, leaf expansion and unfolding, and vine length of sweetpotatoes [Ipomoea batatas (L.) Lam]. Four vine cuttings (15 cm in length) of `TI-155' and `Georgia Jet' were grown for 120 days using a modified half-Hoagland nutrient solution with a 1:2.4 N:K ratio. Irradiance at canopy level averaged 600 μmol·m–2·s–1 at an 18/6 photoperiod, and RH of 70%. Storage root number/plant for both cultivars decreased with increased temperature. Storage root fresh and dry weights for both cultivars increased with temperatures up to 28/22C and declined at 30/24C. Foliage fresh and dry weights were not influenced by temperature for either cultivar. Leaf expansion rate and vine length were highest at 26/20C and lowest at 24/18C for both cultivars. Leaf unfolding rate was not affected by temperature foe either cultivar, but was more influenced by time of measurements.
Growth Analysis of Two Pea Cultivars as Influenced by Planting Date
Authors: Alsadon Abdullah A.
Published: February 2019

`Lincoln' and `Rondo' pea cultivars (Pisum sativum L. subsp. hortense) were planted at early, midseason, and late dates during 1989–90 and 1990–91 growing seasons. Plant growth analysis data were collected via weekly harvests throughout the growing season. Plant height, leaf area, and shoot dry weight were measured, and LAI, SLA, and SLW were also determined. Derived growth quantities such as RGR, NAR, and CGR were calculated. `Rondo' plants were taller, larger in leaf area, had more vegetative and dry weight, and were earlier in flowering than `Lincoln' plants. Leaf area was not significantly affected by planting date. Optimum LAI was obtained between harvests 7 and 9, which coincides with the time of highest values of NAR and CGR. Significant correlation coefficients were obtained between growth attributes in both seasons, and, in most cases, for all planting dates.
A Method for Transforming Whole Plants via the Electrophoresis of Shoot Tips
Authors: Griesbach R.J. , Milo J.
Published: February 2019

Most methods developed to transform plants either require tissue culture to regenerate a whole plant from transformed tissue or the transformation of reproductive tissue. These approaches are not applicable to vegetatively propagated crops or crops that can not be tissue-culture propagated. We have modified a procedure that was developed to transform zygotic meristems for use with whole plant meristems. We developed a method to introduce DNA via electrophoresis into the cells of axillary meristems of whole plants growing in soil. About half of the treated meristems developed into shoots. Of those shoots, up to half had some level of GUS marker gene expression. We were able to transform Cercis, Chrysanthemum, Capsicum, and Prunus. In Capsicum, the GUS gene was inherited.
Contrasting Responses of Amur maackia and Black Locust to Culture in Hoagland Solution
Authors: Aiello Anthony S. , Graves William R.
Published: February 2019

Hydroponic culture of tree seedlings is commonly used to study root biology; however, we have found that species differ in their responses to this practice. Responses of 2-week-old seedlings of Amur maackia (Maackia amurensis Rupr. & Maxim.) and black locust (Robinia pseudoacacia L.) to 1%, 5%, 10%, 25%, 50%, and 100% Hoagland solution #1 were determined over 5 weeks. Dry mass of black locust increased with increasing solution concentration up to 50%. For Amur maackia, dry mass was highest in 5% solution, and dry mass declined by ≈50% in 50% solution. Purpling, chlorosis, and necrosis occurred on leaves of Amur maackia in solutions ≥10%, and symptom severity increased with solution strength. Amur maackia leaf ion content increased dramatically with increasing solution strength; for instance, leaf P content increased 688% as solution strength increased from 5% to 50%. No symptoms occurred on Amur maackia grown in a soil-based medium and irrigated with 50% solution. These data indicate that black locust can be grown hydroponically using standard methods. However, growth of Amur maackia is inhibited at high solution concentrations, suggesting a sensitivity to the availability of ions, and perhaps an enhanced ability to sequester ions from its media.