bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth Retardants Affect Landscape Performance of Zinnia, Impatiens, and Marigold
Authors: Latimer Joyce G.
Published: February 2019

Various spray rates of paclobutrazol, 5000 ppm daminozide, 200 ppm ancymidol, or drought imposition (visible wilt symptoms for up to 2 hours daily) were applied to three bedding plant species to determine effects on growth in the greenhouse and the subsequent growth and performance of treated plants in the landscape. Seedlings of Zinnia efegans Jacq. `Peter Pan Scarlet' responded to all growth retardants (paclobutrazol at 40 and 90 ppm) and the drought treatment in the greenhouse. However, zinnias treated with paclobutrazol or ancymidol still exhibited reductions in plant height 5 and 7 weeks after transplanting to the landscape, and in plant quality (subjective rating of plant appearance with emphasis on flower cover) at 5 weeks after transplanting. Daminozide or drought controlled zinnia growth in the greenhouse but had no carry-over effect in the landscape. Stem elongation of Impatiens wallerana Hook `Accent Red' seedlings was moderately controlled by 20 ppm paclobutrazol in the greenhouse. There were no other treatment effects in the greenhouse. Paclobutrazol (20 ppm) reduced final plant height and quality (7 weeks postplanting). Treatment with daminozide or drought reduced plant width and quality after 5 and 7 weeks in the landscape. Ancymidol had no effect on landscape performance of impatiens. Shoot dry weight gain and stem elongation of Tagetes erects L. `Papaya Crush' seedlings were reduced by ancymidol or 40 ppm paclobutrazol in the greenhouse. Shoot dry weight gain of marigold seedlings was inhibited during the first week of landscape establishment by prior treatment with daminozide, ancymidol, or drought. Final plant height and width in the landscape were not affected by any treatment; however, 40 ppm paclobutrazol, daminozide, or ancymidol decreased final plant quality. Chemical names used: α -cyclopropylα -(4-methoxyphenyl) -5-pyrimidinemethanol (ancymidol); butanedioic acid mono(2,2-dimethylhydrazide) (daminozide); β -[(4-chlorophenyl) methyl] - β - (1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).
Anesthetic Storage of Recalcitrant Seed: Nitrous Oxide Prolongs Longevity of Lychee and Longan
Authors: Sowa Sharon , Roos Eric E. , Zee Francis
Published: February 2019

Seeds of the recalcitrant species lychee (Litchi chinénsis Sonn.) and longan (Dimocarpus longan Lour.) were stored near 100% relative humidity at 8 to 10C in air, 80% nitrous oxide (N2O) plus 20% oxygen, or 100% nitrous oxide. The combination of anesthetic and oxygen extended storage longevity of both species. Seeds stored in 100% N2O lost terminability at the same rate as those stored in air. Lychee seeds retained 92% of initial germination after 12 weeks under 80% N2O/20% O2, while those under air retained only 44%. Longan seeds failed to germinate after 7 weeks under air, yet retained 70% of their initial germination under 809” N2O/20% O2. The combination of anesthetic and oxygen atmospheres could provide a new approach to recalcitrant seed storage.
INFLUENCE OF TIME DURING THE DAY BENZYLADENINE IS APPLIED ON PENETRATION INTO APPLE LEAVES
Authors: Mao Z. Y. , Greene D. W.
Published: February 2019

Penetration of foliar-applied chemicals can be influenced by a number of environmental conditions including: light, temperature, and humidity. These change during the day. 14C-benzyladenine (BA) was applied to the upper or lower surface of McIntosh apple leaves from 6:0 0 to 21:OO hours at 3 hour intervals. The amount of BA entering a leaf over a 24-hour period was not influenced by the time of application. Temperature was correlated with BA retention in the wax layer (correlation coefficients, r=0.06 4 and r=0.70 for the upper and lower surfaces, respectively) and with penetration through the upper surface (r=0.58). BA penetration into the leaf was not correlated with light intensity, relative humidity, or time of droplet drying.
PHYLOGENY OF SELECTED IPOMOEA SPECIES BASED ON ISOZYME AND MORPHOLOGY CHARACTERIZATION
Authors: Reves Luz M. , Collins Wanda
Published: February 2019

Eight populations including Ipomoea batatas and I. trifida species were assayed at six polymorphic enzyme loci. Differences in allele frequencies among populations allowed distinction of the two species and among levels of ploidy. Principal component and cluster analyses using isozyme and morphological data were performed. Results from isozyme characterization in general supported the results from morphological classification. Cluster analysis from isozyme assays indicated that the hexaploid species I. trifida is not a different species than I. batatas but may be a wild type. Significant deviations of genotypic frequencies from Hardy-Weinberg equilibrium in some of the loci were detected and were possibly due to effects of natural selection; this fact was reflected in the level of homozygosity observed among populations for the loci in disequilibrium.
SPECTRAL CHANGES IN METAL HALIDE AND HIGH PRESSURE SODIUM LAMPS EQUIPPED WITH ELECTRONIC DIMMING
Authors: Bubenheim David L. , Sargis Raman , Wilson David
Published: February 2019

Electronic dimming of high intensity discharge lamps offers control of photosynthetic photon flux (PPF) but is often characterized as causing significant spectral changes. Growth chambers with 400 W metal halide (MH) and high pressure sodium (HPS) lamps were equipped with a dimmer system using silicon controlled rectifiers (SCR) as high speed switches. Phase control operation turned the line power off for some period of the AC cycle. At full power the electrical input to HPS and MH lamps was 480 W (RMS) and could be decreased to 267 W and 428 W, respectively, before the arc was extinguished. Concomitant with this decrease in input power, PPF decreased by 60% in HPS and 50% in MH. The HPS lamp has characteristic spectral peaks at 589 and 595 nm. As power to the HPS lamps was decreased the 589 nm peak remained constant while the 595 nm peak decreased, equalling the 589 nm peak at 345 W input, and was almost absent at 270 W input. The MH lamp has a broader spectral output but also has a peak at 589 nm and another, smaller peak, at 545 nm. As input power to the MH lamps decreased the 589 nm peak diminished to equal the 545 nm peak. As input power approached 428 W the 589 nm peak shifted to 570 nm. While a spectral change was observed as input power was decreased in both MH and HPS lamps, the phytochrome equilibrium ratio (Pfr/Ptot) remain unchanged for both lamp types.
Performance of Citrus Scion Cultivars and Rootstock in a High-density Planting
Authors: Wheaton T.A. , Castle W.S. , Whitney J.D. , Tucker D.P.H.
Published: February 2019

`Hamlin' and `Valencia' oranges [Citrus sinensis (L.) Osb.], `Murcott' tangor (C. reticulata Blanco × C. sinensis), and `Redblush' grapefruit (C. paradisi Macf.) on 15 rootstock and own-rooted cuttings were planted at a 1.5 × 3.3-m spacing providing a density of 2020 trees/ha. Growth rate, productivity, and fruit quality varied among the scion and stock combinations. Combinations of moderate vigor and precocious fruiting performed better than very vigorous or dwarfing materials. Several freezes slowed canopy development and delayed production. Most trees had filled their allocated canopy space 7 years after planting. At that age, the orange trees yielded 23 to 75 t·ha-1. Scion and stock combinations with desirable vigor and fruiting characteristics were satisfactory in this high-density planting. However, there appears to be little advantage of high tree density under Florida conditions, and moderate densities of fewer than 1000 trees/ha may be preferable.
Improving the Growth of Newly Planted Apple Trees
Authors: Autio Wesley R. , Greene Duane W. , Cooley Daniel R. , Schupp James R.
Published: February 2019

Increasing the N application rate (in the form NH4NO3 to newly planted `Marshall McIntosh'/M.9 apple (Malus domestica, Borkh.) trees beyond 76 g N per tree per year reduced growth in the first two growing seasons. Peat moss or composted manure mixed into the planting hole of `Royal Gala'/M.26 increased growth in the first growing season after planting. The soil-active fungicides, fosetyl-Al and metalaxyl, increased trunk and shoot growth of `Royal Gala'/M.26 in the first season after planting. Mulching enhanced growth of `Gala'/M.26 only in the third season after planting, a season during which the region experienced a drought. Mulching significantly increased bloom on `Gala'/M.26 2 years after planting. The growth of `Royal Gala'/M.26, `Marshall McIntosh'/M.26, and `Ace Delicious'/M.26 was not affected by planting technique planting by hand in 61-cm augered holes vs. planting with a mechanical tree planter. Chemical names used N-(2,6-dimethyl-phenyl)-N-(methloxyacetyl)alanine methyl ester (metalaxyl); aluminum tris (O-ethyl phosphonate) (fosetyl-Al); 1,1'-dimethyl-4-4'-bipyridinium ion (paraquat); isopropylamine salt of N-(phosphonomethyl) glycine (glyphosate).
Response of Apios americana to Nitrogen and Inoculation
Authors: Putnam D.H. , Heichel G.H. , Field L.A.
Published: February 2019

Apios americana Medikus (apios) is a wild tuberous legume with potential as a crop plant. Five apios accessions were grown in sand culture in two greenhouse experiments to examine the effect of N fertilization and inoculation with Bradyrhizobium japonicum on yield and plant characteristics. A common soybean B. japonicum strain (USDA76) was applied to plants watered with 0, 50, 100, 200, or 300 ppm N solutions (NH4NO3), plus a complete nutrient solution. At 0 N, total dry matter yield of noninoculated plants was only ≈ 30% of inoculated plants. However, total dry-matter yields of inoculated plants at 0 N were only ≈77% of plants supplemented with 50 or 100 ppm, indicating that inoculation alone was insufficient to meet the N needs of the plant. Tuber weight was increased by both N and inoculation, but tuber weight decreased at N concentrations >100 ppm. Differences among plant accessions with regard to tuber fresh weight, harvest index, and modulation were found. These studies indicated that N fertilization maybe required to maximize tuber yields of apios.
Detection of Citrus Leaf and Seed Glycoproteins using Biotinylated Lectin Probes
Authors: Niedz Randall P. , Bausher Michael G. , Hearn C. Jack
Published: February 2019

leaf and seed glycoproteins were detected after sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and electroblotting onto polyvinylidene difluoride (PVDF) membrane when probed with biotinylated lectin at 1 μg·ml-1. Four lectins representing three carbohydrate-binding groups were used as probes. A preformed avidin-biotin-complex (ABC) was used to detect the glycoprotein-bound lectins and resulted in dark bands and little background staining. Concanavalin A (ConA) and wheat germ agglutinin (WGA) resulted in the darkest-staining bands. The four Citrus spp. and one related species studied had unique seed glycoprotein profiles when probed with ConA and WGA. This procedure might be useful in clarifying citrus taxonomy, providing genetic markers, and in physiological studies involving glycoproteins.
Callus Induction and Plantlet Regeneration in Tissue Cultures of Hawaiian Anthuriums
Authors: Kuehnle A.R. , Sugii N.
Published: February 2019

Leaf explants of seven cultivars of Hawaiian anthuriums (Anthurium andraeanum Linden ex André cv. Kaumana, Kozohara, Marian Seefurth, Mauna Kea, Nitta, Ozaki, and Paradise Pink) produced callus most successfully after 2 to 3 months on a modified Pierik medium containing 0.36 μm 2,4-D and 4.4 μm BA. Petiole explants callused best on Pierik modified Pierik, and Finnie and van Staden media. Long-term cultures of callus from Univ. of Hawaii anthurium selections UH965, UH1060, and UH1003 were maintained for 12 to 13 months and were still capable of plantlet regeneration. Adventitious plantlets were recovered from callus plated on a Kunisaki medium containing 2.2 or 22 μm BA. Regeneration appeared to be organogenic rather than embryogenic and varied among the genotypes tested. Chemical names used: N- (phenylmethyl)-1H-purin-6-amine (BA); (2,4-dichlorophenoxy) acetic acid (2,4-D).
Growth and Composition of Passion Fruit (Passiflora edulis) and Maypop (P. incarnata)
Authors: Arjona Harvey E. , Matta Frank B. , Garner James O.
Published: February 2019

Fruit growth (diameter) of purple passion fruit (Passiflora edulis Sims.) and maypop (P. incarnata L.) followed a sigmoidal growth curve. Passion fruit were larger than either greenhouse-grown or wild maypop fruit. Wild maypop produced larger fruit than greenhouse-grown maypop. Yellow passion fruit had the lowest percentage of pulp and the highest soluble solids concentration (SSC) and greenhouse-grown maypop had the lowest SSC among the four groups tested. Purple and yellow passion fruit had lower juice pH than maypop. Wild maypop fruit had the highest sucrose content and purple passion fruit had the lowest. Yellow and purple passion fruit juice had higher fructose and glucose contents than did maypop juice.
Quality of Stored `Marsh' and `Ruby Red' Grapefruit after High-temperature, Forced-air Treatment
Authors: Miller W.R. , McDonald R.E.
Published: February 2019

`Marsh' and `Ruby Red' grapefruit (Citrus paradisi Macf.) tolerated a high-temperature, forced-air, vapor heat treatment of 43.5C for 260 minutes, a treatment applied for security against the Caribbean fruit fly [Anastrepha suspensa (Loew)]. Fruit did not develop symptoms of quality deterioration during subsequent storage. With `Marsh' fruit, 99% and 96% were sound, whereas with `Ruby Red' 98% and 94% were sound after storage at 10C for 28 days or 10C for 28 days plus 7 days at 21C, respectively. Differences in means for percentage of sound fruit were not significant for cultivar or vapor heat treatment. After the final storage period, there was significantly more (2.4-fold, P ≤ 0.05) aging observed on `Ruby Red' fruit than on `Marsh', averaged over all treatments. Vapor heat did not affect aging of `Ruby Red' but increased aging of `Marsh' fruit. Decay was reduced to ≈ 22.0% in vapor heat-treated fruit from 5.0% for nontreated fruit. The efficacy of thiabendazole to control stem end rot was increased on vapor heat-treated fruit compared with nontreated fruit. After the final inspection, the appearance of `Marsh' fruit was fresher (index 2.0) than that of `Ruby Red' fruit (index 2.3), but the appearance of vapor heat-treated and nontreated fruit was similar. Peel color of `Ruby Red' fruit was not affected by the vapor heat treatment, but, after 4 weeks at 10C plus 1 week at 21C, `Marsh' fruit that were not treated were greener than those treated with vapor heat. The vapor heat treatment tested is a potentially viable quarantine procedure for Florida grapefruit that can be applied without adversely affecting fruit quality during normal storage.
Osmotic Adjustment and the Growth Response of Seven Vegetable Crops following Water-deficit Stress
Authors: Wullschleger Stan D. , Oosterhuis Derrick M.
Published: February 2019

Growth-chamber studies were conducted to examine the ability of seven vegetable crops-`Blue Lake' bean (Phaseolus vulgaris L.), `Detroit Dark Red' beet (Beta vulgaris L.), `Burgundy' okra (Abelmoschus esculentus (Moench), `Little Marvel' pea (Pisum sativum L.), `California Wonder' bell pepper (Capsicum annuum L.), `New Zealand' spinach (Spinacia oleracea L.), and `Beefsteak' tomato (Lycopersicon esculentum Mill.)–to adjust osmotically in response to water-deficit stress. Water stress was imposed by withholding water for 3 days, and the adjustment of leaf and root osmotic potentials upon relief of the stress and rehydration were monitored with thermocouple psychrometers. Despite similar reductions in leaf water potential and stomata1 conductance among the species studied, crop-specific differences were observed in leaf and root osmotic adjustment. Leaf osmotic adjustment was observed for bean, pepper, and tomato following water-deficit stress. Root osmotic adjustment was significant in bean, okra, pea, and tomato. Furthermore, differences in leaf and root osmotic adjustment were also observed among five tomato cultivars. Leaf osmotic adjustment was not associated with the maintenance of leaf growth following water-deficit stress, since leaf expansion of water-stressed bean and pepper, two species capable of osmotic adjustment, was similar to that of spinach, which exhibited no leaf osmotic adjustment.
Inheritance of Phosphoglucomutase Isozymes in Pecan
Authors: Marquard Robert D.
Published: February 2019

Six phosphoglucomutase phenotypes were observed in pecan [Carya illinoensis (Wangenh.) K. Koch] progeny after controlled pollinations. At least one locus (Pgm-1) is present that controls polymorphism of phosphoglucomutase (PGM) isozymes in pecan. The inheritance appears simple with three observed alleles. However, progeny produced from two crosses resulted in significant deviation from the expected segregation ratios. Out of 65 named cultivars, 61 were of a single phenotype, and two of six possible phenotypes were not observed. Only one region of PGM activity was consistently expressed by gel electrophoresis from pecan tissue.
Heritable Differences in Postproduction Quality of Pelargonium ×domesticum
Authors: Deneke C. Frederick , Glicenstein Leon J. , Evensen Kathleen B. , Craig Richard
Published: February 2019

The postproduction quality of 33 cultivars and 178 Pennsylvania State Univ. breeding lines of Pelargonium ×domesticum L.H. Bailey was evaluated in a simulated consumer environment. Petal abscission was the primary factor that reduced postproduction ratings (PPR). The heterozygosity of some cultivars was indicated by the range of PPR of progeny from self-pollinations. This range of PPR implies that P. ×domesticum has genetic variation for postproduction quality that can be used in a breeding and selection program. Few progeny with high PPR were produced from either self- or cross-pollinations involving parents with low PPR. Many of the superior progeny resulted from parents with high PPR. Therefore, progeny with improved postproduction quality can be developed by selecting parents with high PPR.
Variation in Flower Senescence and Ethylene Biosynthesis among Carnations
Authors: Brandt Amanda S. , Woodson William R.
Published: February 2019

We have investigated the patterns of ethylene biosynthesis in carnation (Dianthus caryophyllus L.) genotypes that exhibit extended vase life in comparison to flowers of White Sim'. `White Sim' flowers exhibited typical symptoms of senescence, including petal in-rolling and rapid wilting, beginning 5 days after harvest. In contrast, the other genotypes studied did not show petal in-rolling or rapid wilting associated with petal senescence. The first visible symptom of senescence in these flowers was necrosis of the petal tips, and it occurred from 3 to 7 days after the initial symptoms of senescence were seen in `White Sim' flowers. In all cases, the extended-vase-life genotypes did not exhibit the dramatic increase in ethylene production that typically accompanies petal senescence in carnation. This appeared to be the result of limited accumulation of ACC. In addition, flowers of these genotypes had limited capacity to convert ACC to ethylene. Therefore, we conclude that the low level of ethylene produced by these flowers during postharvest aging is the result of low activities of both ACC synthase and the ethylene-forming enzyme. Treatment of `White Sim' flowers at anthesis with 1.0 μl ethylene/liter resulted in the induction of increased ethylene biosynthesis and premature petal senescence. The extended-vase-life genotypes exhibited varying responses to ethylene treatment. One genotype (87-37G-2) produced elevated ethylene and senesced prematurely, as did flowers of `White Sim'. A second genotype (82-1) was induced to senesce by ethylene treatment but did not produce increased ethylene. A third genotype (799) was unaffected by ethylene treatment. The results of this study suggest these extended-vase-life genotypes are representative of genetic differences in the capacity to synthesize and respond to ethylene. Chemical name used: 1-aminocyclopropane-1-carboxylic acid (ACC).
Self- and Cross-pollination Affect Stigmatic Pollen Saturation in Blueberry
Authors: Parrie E. James , Lang Gregory A.
Published: February 2019

Pollen deposition on the stigmatic surface of blueberry pistils was studied with regard to maximum pollen load and stigmatic fluid production (stigma receptivity). Three hybrid southern highbush cultivars (Vaccinium corymbosum L. with V. darrowi Camp, V. ashei Reade, and/or V. angustfolium Aiton), two northern highbush cultivars (V. corymbosum), and one hybrid half-high cultivar (V. corymbosum with V. angustifolium) were selfand cross-pollinated with counted pollen tetrads until saturation of the stigmatic surface occurred. Stigmatic saturation generally required 200 to 300 tetrads and was characterized by the cessation of stigmatic fluid production and the inability to absorb further tetrads. The loss of stigmatic receptivity was irreversible. Cross-pollination resulted in cessation of stigmatic fluid production at lower levels of tetrad deposition than did self-pollination, suggesting a potential pollen-stigma recognition phenomenon. Northern highbush, half-high, and southern highbush cultivars required 7% to 10%, 12% to 17%, and 14% to 21%, respectively, more self-pollen to develop the stigmatic saturation condition. The potential relation of the pollenstigma phenomenon to self-incompatibility mechanisms is discussed.
Variation in Bloom Time in a Sour Cherry Germplasm Collection
Authors: Iezzoni Amy F. , Mulinix Colleen A.
Published: February 2019

Bloom times were evaluated for seedlings from four full-sib and 14 open-pollinated families of sour cherry (Prunus cerasus L.). Time of anthesis for individual seedlings ranged over 17and 16-day periods in 1989 and 1990, respectively. In both years, most seedlings bloomed later than `Montmorency', the only commercially important sour cherry cultivar in the United States. `Pitic de Iasi', the parent of the latest-blooming family, is a natural interspecific hybrid between sour cherry and the cold-hardy Russian ground cherry (P. fruticosa Pall.). Hybridization between sour and ground cherry and intense selection pressure in the colder areas of the sour cherry habitat may have favored selection of the late-blooming character.
PELLETIZED SEWAGE SLUDGE AS A TURFGRASS FERTILIZER.
Authors: Mackintosh S. A. , Cooper R. J.
Published: February 2019

Environmental concerns associated with traditional methods of sludge disposal have spurred research exploring alternate avenues of disposal. A potentially significant alternative is the beneficial use of sludge as a turfgrass fertilizer. Studies were initiated during 1991 to compare a commercially available pelletized sludge to urea; 12-4-6; Ringer Lawn Restore; and Milorganite. Fertilizers were evaluated for their effect on turfgrass quality, color, and growth rate. Treatments were applied to a stand composed of 65% Kentucky bluegrass (Poa pratensis L. `Baron') and 35% Perennial ryegrass (Lolium perenne L. `Manhattan II') in South Deerfield, MA. Urea and 12-4-6 were applied at 49 kg N ha-1. Ringer Lawn Restore and Milorganite were applied at 98 kg N ha-1. Pelletized sludge was applied at 98, 196, 294, and 392 kg N ha-1 with all rates providing acceptable to good turfgrass color throughout the season. Rates of 294 or 392 kg seldom provided quality better than the 196 kg rate. While urea initially produced quality superior to pelletized sludge, all rates of sludge resulted in quality equal to or better than urea beginning one month after application and lasting approximately 11 weeks. Turf receiving similar rates of either pelletized sludge or Milorganite performed similarly. No sludge application rate produced burning or foliar discoloration. Clipping production was directly related to sludge application rate. Pelletized sludge applied at 98 kg N ha-1 resulted in growth comparable to similar applications of Ringer Lawn Restore and Milorganite. In summary, using pelletized sewage sludge as a turfgrass fertilizer promotes healthy turfgrass while creating an alternate avenue of sludge disposal.
CHARACTERISTICS OF UV ABSORBANCE BY HEXANE EXTRACTS OF APPLE SURFACES SUGGEST A MODIFIED HYPOTHESIS ON THE ROLE OF CONJUGATED TRIENES IN SCALD DEVELOPMENT ON APPLES
Authors: Du Zhanyuan , Bramlage William J.
Published: February 2019

Much correlative data support the hypothesis that superficial scald on apples results from oxidation of α farnesene to conjugated trienes (CT) in the coating of apples. However, these associations are poorly defined both chemically and physiologically. α Farnesene and CT are measured as OD 232 and OD 281-290, respectively, of a hexane extract of the fruit surface. During assays, we observed anomalies in absorbance characteristics of extracts from fruit with different scald potentials, particularly in the region of 258 nm. Results suggest that absorbance near 258 nm might represent a metabolite of CT, which may be further metabolized. It appeared that under different conditions, CT metabolism could be altered, resulting in changed ratios of OD 258/OD 281. Higher ratios correlated with lower scald development, regardless of CT concentration. Thus, CT metabolism, rather than its concentration, may determine if scald occurs.
SAMPLING METHOD AFFECTS MINERAL ANALYSES OF DELICIOUS APPLE FRUIT
Authors: Weis Sarah A. , Bramlage William J.
Published: February 2019

Fifty four trees in a block of `Sturdeespur' Delicious on M.106 rootstock were given soil applications of various combinations of boron and gypsum. Twenty 2.9 to 3.0 inch diameter fruit and 20 unsized randomly chosen fruit were separately weighed and analyzed for Ca, Mg, K, and B concentrations. The coefficient of variation among fruit weights was greater for unsized than sized samples. Analyses of variance showed similar treatment effects for the two sampling methods. However, by using both sized and unsized fruit, effects of treatment on fruit size, and effects of relationships between fruit size and fruit mineral concentration may be separated.
DISTORTED MENDELIAN INHERITANCE OF THE FUSED VEIN TRAIT IN CUCURBITA PEPC L.: A CASE FOR GAMETIC SELECTION
Authors: Carle R. Bruce , Loy J. Brent
Published: February 2019

The recessive leaf trait, fused vein (fv), in Cucurbita pepo L. is expressed by the sixth leaf stage and then throughout vegetative growth. It is characterized by the partial fusion of the lateral leaf veins to the main central vein. Consequently, the dorsal leaf surface is distinctively puckered. Use of fv as a genetic marker in hull-less seeded pumpkin lines is hampered, however, by a low recovery of fv plants in segregating populations. Homogeneity Chi Square analysis of 11 F2 (3:1 X2 = 72.05 P < 0.005) and 16 BC (1:1 X2 = 120.12 P < 0.005) populations indicated significant heterogeneity between populations for fv recovery. Recovery ranged from 0 to 35.5% for 11 F2 populations and from 6.8 to 75.4% for 16 BC populations. There was a significant reduction, 35%, in seed yield/fruit when fv pollen was used to hand pollinate fv, normal (N), and F1 flowers as compared to pollinations with N pollen. In pollen competition studies, reduced competition at low levels of F1 or 50:50 fv/N pollen increased fv recovery in F2 and BC populations. These results are consistent with the hypothesis that the fv trait confers gametic subvitality resulting in distorted Mendelian segregation.
EARLIER VEGETABLE CROPS WITH NEAR INFRA-RED TRANSMITTING MULCH
Authors: Loy Brent , Wells Otho
Published: February 2019

Near infra-red (NIR)-transmitting plastic mulches transmit between 30 to 50% of the total solar energy to the soil, but block most photosynthetically active radiation (PAR). These mulches warm the soil more effectively than black plastic, but less effectively than clear mulch. Weed growth under NIR-transmitting mulches is suppressed through a combination of lowered light intensity and high temperatures under the mulch surface. With bell pepper and melons, IRT-76, a blue green, NIR-transmitting mulch, enhances growth to about the same extent as black mulch plus a floating rowcover. In turn, rowcover performance is enhanced by IRT-76 as compared to black mulch. In melons, early yield is about doubled and total yields increased by 20 to 30% with IRT-76 as compared to black mulch. Pepper yields are generally higher with IRT-76 as compared to black mulch, but the yield response to IRT-76 is less consistent than with melon.
CULTURAL PRACTICE ADAPTATION FOR MECHANICALLY HARVEST PICKLING CUCUMBERS
Authors: Kee Ed
Published: February 2019

Mechanically harvested pickling cucumbers are a once-over destructive harvest system. Gynoecious hybrids are planted at high populations to obtain high yields and to concentrate maturity. Population, row width, plant spacing, and uniform emergence all affect yield and maturity. 65,000 plants/acre in 26 inch rows were found to optimize yield and provide the highest percentage of fruit at the desired uniform size.
POLLUTION AND DEVELOPMENT OF TOMATO POLLEN
Authors: Zhang Yuan-Hai , Craker Lyle E.
Published: February 2019

Air pollution may play a role in gametophytic selection. To estimate whether such selection was occurring, pollen grains from homozygous and heterozygous tomato plants were tested under pollution stress. Homozygous pollen could be expected to respond to pollution more uniformly than heterozygous due to the identical genotype of the pollen grains. Acid rain reduced pollen germination and tube elongation in Lycopersicon hirsutum LA1777 (heterozygous) and Lycopersicon pennellii LA716 (nearly homozygous). UV-B reduced tube length of the pollen from both plants, but ozone only reduced pollen tube length of L. pennellii. The responses of these two kinds of pollen to acid rain, ozone, and UV-B appears to be same in terms of heterozygosity and stress dosages, suggesting the reduction of pollen germination and tube elongation under pollution stress may be mediated through physiological or physical alterations and not a response of different genotypes.
STIMULATING LANDSCAPE AWARENESS FOR FUTURE GENERATIONS
Authors: Hatchell Michael , Haque Mary , Caldwell Judy
Published: February 2019

The City of Clemson, South Carolina recently received funding from America the Beautiful to develop a community/government/educational partnership. The purpose of this project was to promote tree planting initiatives and awareness for future generations as well as to enhance our city and its roadsides. The project involved completing a tree inventory and landscape design for Highway 123, a major highway into Clemson. Presentations were made to city officials and approvals obtained by the highway department before implementation took place. Over 100 trees were planted and an educational pamphlet was published to illustrate the streetscape project and to serve as a guide for city officials. My presentation outlines the goals, methodology and results of this project.
SCHEDULING MELON TRANSPLANTING TO MEET SPECIFIC HARVEST WINDOWS IN SOUTHWEST INDIANA
Authors: Simon James E. , Scott W. Dennis , Wilcox Gerald
Published: February 2019

A study was initiated at the Southwest Purdue Ag Center to demonstrate the effect of transplant age and transplanting date on the scheduling of melon harvests. Muskmelon (Cucumis melo cv. Superstar) was seeded into #38 growing trays with Jiffy-mix media. Seeding dates were such that 14 and 21 day old seedlings were transplanted April 25, May 9, 17 and 24. The plants were grown on black plastic with trickle irrigation Marketable fruit were harvested starting on June 28 and continuing through August 12. Neither transplant age or date had a significant effect on the number of fruit harvested or on total yield. However, each transplant date showed a distinctive harvest peak beginning June 30 for the April 26 transplant then June 7, 14 and 21 for each successive transplant date.
ATTITUDES AND PERCEPTIONS OF CHOOSE-AND-CUT CHRISTMAS TREE CONSUMERS
Authors: Florkowska Malgorzata A. , Lindstrom Orville M. , Florkowski Wojciech J.
Published: February 2019

A survey was conducted to investigate consumer preferences in a Christmas tree purchase. The survey asked about consumers' socioeconomic status, customer loyalty and on farm buying habits, specific tree preferences, and preferences of live versus artificial trees. Fifty-three percent of the 148 respondents were male and 61% were between the ages of 25-44. Thirty-three percent had 3 children, 50% were college graduates and 59X had a family income greater than $35,000. Sixty-eight percent purchased their tree at the same farm as they did the previous year, 62% traveled from 1-10 miles to the farm, 50% of trees were purchased by December 8, and 70% of the purchases were during the afternoon. The most common tree selected was a 6-7 ft. Virginia Pine and selection time ranged from 5-30 minutes. Compared to an artificial tree, respondents cited messiness, difficulty to carry and trouble to remove as major drawbacks of choose-and-cut Christmas trees. This was particularly evident in female and elderly respondents.
WATER VAPOR TRANSMISSION RATES OF CELGARD® D-304 MICROPOROUS, POLYPROPYLENE FILMS
Authors: Dellevigne Laura , Vergano Peter , Wiles Lee , Hale Andy , Adelberg Jeff
Published: February 2019

Commercially produced membrane rafts containing Celgard D-304 microporous, polypropylene film are used to support the growth of micropropagated plants in liquid media. This method is used because growth experiments using membranes resulted in plant growth rates equal to or greater than those grown on agar. Inconsistent results of plant growth on these rafts led to an interest in measuring the water vapor transmission rates (WVTR) of the membranes. A modified WVTR test (ASTM E96-80) was used on 15 raft samples. Results showed that the supplier's value of 49.2 g/m2 ·hr falls within the range of measured values of 39.2 to 54.8 g/m2·hr. Inconsistencies in growth of micropropagated plants may not be due to variability in the WVTR of the Celgard film. It is possible that the WVTR of the film is not the most important factor in facilitating liquid nutrient transport across the membrane. Other properties of the film need to be measured to determine factors affecting growth rates observed.
EVALUATION OF POD DETACHMENT FORCE IN SOUTHERNPEA
Authors: Buckley Blair , Pee Katharine
Published: February 2019

Ease of pod detachment is an important consideration when selecting cultivars for mechanical harvest at the mature-green stage. Sixteen southernpea cultivars and breeding lines were evaluated for pod detachment force. The cultivars varied in pod detachment force. MN-13 had the largest detachment force with a measurement of 2.18 kg. Royal Cream had the smallest detachment force with a measurement of 1.2 kg. Pod length, pod diameter, pod weight, basal pod fill, and length of peduncle synapse was recorded for each pod sampled for detachment force. There was no clear association between pod detachment force and the five traits.
The Vacuum-Operated Nutrient Delivery System: Hydroponics for Microgravity
Authors: Brown Christopher S. , Cox William M. , Dreschel Thomas W. , Chetirkin Peter V.
Published: February 2019

A nutrient delivery system that may have applicability for growing plants in microgravity is described. The Vacuum-Operated Nutrient Delivery System (VONDS) draws nutrient solution across roots that are under a partial vacuum at ≈91 kPa. Bean (Phaseolus vulgaris L. cv. Blue Lake 274) plants grown on the VONDS had consistently greater leaf area and higher root, stem, leaf, and pod dry weights than plants grown under nonvacuum control conditions. This study demonstrates the potential applicability of the VONDS for growing plants in microgravity for space biology experimentation and/or crop production.
Elemental Sulfur Lowers Redox Potential and Produces Sulfide in Putting Green Sand
Authors: Berndt W.L. , Vargas J.M.
Published: February 2019

Biological production of sulfide (S2-) in soil has been reported to depend on system redox potential and on the concentrations of available sulfate () and organic carbon (OC). The purpose of this laboratory study was to determine whether elemental sulfur (So) could influence redox potential and S2- production in sand used to construct putting greens. Treatment with So depressed redox potential as pe + pH, and stimulated accumulation of both free H2S and acid-soluble S2-. Organic carbon as lactate (C3H5O3Na) intensified the effects of So, primarily by influencing pH. Thus, So application could induce anaerobiosis and subsequently affect turf quality by heightening production of free hydrogen sulfide (H2S). It could also contribute to S2- accumulation possibly expressed as a black layer or blackening of the root zone.
Growth of New Guinea Impatiens Inhibited by High Growth-medium Electrical Conductivity
Authors: Judd Laura K. , Cox Douglas A.
Published: February 2019

To test the effects of fertilizer concentration and growth medium electrical conductivity (EC) on the growth of New Guinea impatiens (Impatiens sp. hybrids or I. platypetala Lindl.), plants of `Selenia' were grown 70 days in a commercial soilless medium and irrigated with solutions of 20N-4.3P-16.6K at concentrations of 0.5, 1.0, 1.5, or 2.0 g·liter-1. In a fifth treatment (“delay”), no fertilizer was applied for the first 14 days after planting, then 0.5 g·liter-1 was applied for the next 14 days, followed by 1.0 g·liter-1 until the end of the experiment. Measurements of shoot dry weight and growth medium EC were made at 14-day intervals. Differences in dry weight between fertilizer treatments became significant (P = 0.0001) 42 days after planting. Over the 70-day experiment, plants grew most with 0.5 g·liter-1 and delay treatments. High fertilizer concentrations (1.5 and 2.0 g·liter-1) caused the most growth suppression and resulted in increasing growth medium EC with time. An EC of ≈1.5 dS·m-1 or higher was associated with suppressed growth beginning 42 days after planting. A mild chlorosis developed on the leaves of some plants at the two highest fertilizer concentrations.
NACL STRESS ALTERS PRIMARY CELL WALL TENSILE STRENGTH IN THE HALOPHYTIC GRASS, DISTICHLIS SPICATA L.
Authors: Lopez-Gutierrez Francisco , Hughes Harrison G. , Carpita Nicholas C.
Published: February 2019

After 6 months of growth in 200,400, and 500 mm NaCl, cultured cells of Distichlis spicata showed a decreased cell volume (size) despite maintenance of turgor pressure sometimes 2-fold higher than that of the control. Tensile strength, as measured by a nitrogen gas decompression technique, showed empirically that the walls of NaCl-stressed cells were weaker than those of nonstressed cells. Breaking pressures of the walls of control cells were ≈68 ± 4 bars, while that of the walls of cells grown in 500 mm NaCl (-25 bars) were 14 ± 2 bars. The relative amount of cellulose per cell remained about constant despite salt stress. However, glucuronoarabinoxylans were more readily extractable, presumably because of a decrease in cross-linkage with phenol substances. Therefore, we suggest that cellulose microfibrils are not the only determinants that confer tensile strength to the primary cell wall, but rather subtle changes in the matrix polysaccharides are likely responsible for this event.
EFFECTS OF 60COBALT IONIZING IRRADIATION ON GROWTH AND POLYSOME CONTENT IN PISUM SATIVUM L. `ALASKA'
Authors: Goodrich Jody A.
Published: February 2019

This research tested the hypothesis that 60Co ionizing irradiation degrades polysomes to monosomes, a process that reduces growth of Pisum sativum seedlings. Dry and imbibed seeds and 5-day-old seedlings were exposed to 1.8, 3.6, 7.2, 14.4, or 28.8 krad of 60Co irradiation. Immediately after irradiation treatments, dry and imbibed seeds were planted, and later seedlings were harvested and analyzed. Five 1-cm root-tip samples from 5-day-old seedlings were crushed and layered onto 15% to 60% sucrose gradients and centrifuged for 55 min. The samples were processed through an ISCO ultraviolet chart maker. The monosome and polysome weights were read and analyzed. The monosome content was greater in the irradiated 5-day-old seedlings than in seedlings from dry and imbibed seeds. The growth of 5-day-old irradiated seedlings and seedlings from imbibed seeds was less than that of seedlings from dry seeds. The reduced growth of the irradiated seedlings suggests damage to the polysomes. When protein synthesis in plant cells is altered, perhaps through RNA decoding mechanisms, growth may be partially or completely arrested. Using sensitive plants to establish the injurious effects of ionizing irradiation on living organisms can educate and alert society to the detrimental effects of overexposure to irradiation such as that caused by nuclear accidents.
FARMER'S BOOKSHELF FOR THE IBM: A HYPERMEDIA PERSONAL INFORMATION MANAGEMENT SYSTEM FOR CROPS
Authors: Kobayashi Kent D. , Bittenbender H.C.
Published: February 2019

The objective of this study was to develop a computerized personal information management system for use by extension agents and growers. Agents and growers need an easy-to-use computer information system to access quickly information about specific topics for different crops. An information system helps agents provide faster, better service and up-to-date information to their clients. Using the software LinkWay (IBM Corp.) on an IBM personal computer, we developed such a system called the “Farmer's Bookshelf for the IBM.” This information system uses “index cards” with information stored on separate screens called “pages.” Both textual and graphical information may appear on a page. Using a mouse, the user navigates from one page to another by clicking on a “button” on the page. This easy-to-use system requires no typing except to enter a word for the computer to search. The user can easily browse for the desired information and then print it. The “Farmer's Bookshelf for the IBM” provides an easy, fast tool for agents and growers to obtain vitally needed information.
Shade and Photoperiod Influence Caryopteris incana Used as Cut Flowers
Authors: Armitage Allan M. , Son Ki-Cheol
Published: February 2019

Plants of blue spirea (Caryopteris incana Mig.) were evaluated as cut flowers in the field and greenhouse. When subjected to several photoperiods but similar cumulative quanta, plants flowered more rapidly at 8 hours than at 12 hours and did not reach the macrobud stage at 16 hours. Stems were longer and their count was significantly higher with a 16-hour than an 8-hour photoperiod. In the field, yield and stem diameter were similar in full sun and in 55% shade. Stem length, however, significantly increased under shade.
A Trough System for Measuring Transmission of Tomato Ringspot Virus by Dagger Nematodes
Authors: Mountain W.L. , Powell C.A. , Forer L.B.
Published: February 2019

A trough system was developed to study rates of plant virus transmission by plant parasitic nematodes. Perforated plumber's polyvinyl chloride pipe, 5 cm in diameter, was cut into 48-cm lengths, split longitudinally, and fashioned into troughs to hold soil and common dandelion (Taraxacum officinale Webber) transplants. The first plant in each trough was infected with tomato ringspot virus (TmRSV), followed by 10 uninfected plants spaced at 4-cm intervals. The soil contained a high concentration of Xiphinema rivesi (199 per 100 cm3), a low concentration (16 per 100 cm3), or none. Plants were assayed biweekly for TmRSV. After 42 weeks, transmission rates between the low and high concentrations of nematodes were not significantly different. The subirrigated trough system provided excellent soil conditions for plant growth and sufficient nematode survival to detect virus transmission through 36 weeks.
Physiological Changes Associated with Development of Mealiness of Apple Fruit during Cool Storage
Authors: Harker F.R. , Hallett I.C.
Published: February 2019

The relationships between cellular characteristics of cortical tissue from `Braeburn' apple fruit (Malus domestica Borkh.) that had been harvested at two maturities and changes in texture that occurred during storage at 0C were studied. Tensile tests were used to measure adhesion between neighboring cells, and turgor pressure was manipulated to determine the pressures required to burst cells. Apples of advanced maturity became mealy during cool storage, while those of less advanced maturity did not. Mealiness was associated with low adhesion between neighboring cells, and a relatively high resistance to cell rupture.
Cold Storage Influences Internal Characteristics of Nectarines during Ripening
Authors: von Mollendorff L.J. , Jacobs G. , de Villiers O.T.
Published: February 2019

`Flavortop' nectarines [Prunus persica (L.) Batsch] were stored at -0.5C or 3C for 0, 1, 2, 3, or 4 weeks, after which the fruit was ripened at 15C. After ripening, fruit samples were tested daily or every second day for extractable juice, internal conductivity, and woolliness. The change in the percentage of extractable juice during ripening differed very little among the five storage periods. A rapid increase in internal conductivity occurred during ripening in fruit with or without cold storage, but the onset of the increase was advanced with longer cold-storage periods. No woolliness developed in fruit not placed in cold storage or in fruit cold-stored for 1 or 2 weeks at - 0.5C or 3C. Woolliness only developed during ripening of fruit cold-stored for 3 or 4 weeks at -0.5C or 3C. Incidence of woolliness increased to high levels during ripening and decreased thereafter to no woolly fruit by the 11th day. The lowest values for extractable juice coincided with the highest incidence of woolly fruit. Fruit stored for 4 weeks took longer to pass the woolliness stage. At the end of the ripening. period, cold-stored fruit were similar in appearance and juiciness to those ripened without cold storage. Nectarines stored at 3C generally developed woolliness earlier, had a lower incidence of woolliness, and took longer to overcome the problem than fruit stored at -0.5C. Incidence of browning of the mesocarp tissue was greater at 3C than at -0.5C.
Respiration and Carbohydrate Metabolism during Germination of sh2 and Sh2 Sweet Corn Seed
Authors: He Lisha , Burris J.S.
Published: February 2019

Sweet corn (Zea mays var. rugosa L.) seed with the endosperm mutant shrunken-2 (sh2) often exhibit low seed vigor and poor field emergence. Seed respiration and carbohydrate metabolism during germination of supersweet `Jubilee' (sh2) and sugary sweet `Jubilee' (Sh2) were studied. There were no significant vigor differences expressed by isolated embryos from sh2 and sugary (Sh2) seeds, indicating similar embryo physiology. Respiration rates were higher in the sh2 genotype during early stages of germination (24 hours) while they declined later. The available sucrose originating from the endosperm reserves was depleted by day 4. This insufficiency of a sustained energy source due to rapid consumption and minimal stored reserves may limit subsequent seedling growth in the sh2 genotype.
Carrot Yield when Grown under Three Soil Water Concentrations
Authors: White James M.
Published: February 2019

`Orlando Gold' carrots (Daucus carota L.) were grown in plastic containers filled with an organic soil and placed in a greenhouse in the fall and spring. Three (high, medium, and low) soil water concentrations of 48% (low), 54% (medium), and 60% (high) were used. The number of marketable roots was higher following the fall than the spring planting. The high and low soil water concentrations significantly reduced the number of marketable roots over the medium concentration, but only the high concentration reduced the total marketable weight in both plantings. Application of the high soil water concentration reduced root length but not width measured at 2.5 cm below the crown relative to the medium and low soil water concentrations. Carrots will produce marketable roots when grown in a wide range of soil water concentrations, but the high concentration reduced yield more than the low concentration.