bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reflective Film Mulches, Millet Barriers, and Pesticides: Effects on Watermelon Mosaic Virus, Insects, Nematodes, Soil-borne Fungi, and Yield of Yellow Summer Squash1
Authors: Chalfant R. B. , Jaworski C. A. , Johnson A. W. , Sumner D. R. 
Published: August 2022

Abstract
Field studies were conducted in 1973 and 1974 to determine the effects of various reflective film mulches, vegetal barriers of millet (Pennisetum americanum (L.) K. Schum), and soil- and foliar-applied pesticides on yields and control of the watermelon virus complex (WMV), insects, nematodes, and soil-borne pathogens affecting yellow summer squash (Cucurbita pepo var melopepo L. Alefi, ‘Dixie’). All film mulches used (aluminum; white and blue plastic; brown paper) significantly reduced WMV in both fruits and plants. The millet barrier caused a significant reduction in WMV infected plants. In 1974, the systemic insecticide, carbofuran (Furadan) and/or sprays of mineral oil, significantly reduced WMV in non-mulched plots. Brown paper mulch significantly increased infestation of pickleworms, Diaphania nitidalis (Stoll) and all mulches significantly reduced infestations of serpentine leafminers, Liriomyza munda Frick. Leafminers were also controlled with carbofuran. Film mulches had no significant effect on populations of plant-parasitic nematodes and plant-pathogenic fungi. Both groups of pests were controlled with DD-MENCS (a mixture of 1,3-dichloropropene, 1,3-dichloropropane, methylisothiocyanate), but not with carbofuran or sodium azide. Film mulch increased squash yield 70 to 610% over the unmulched control. Plants in non-fumigated plots covered with aluminum and white plastic mulches produced significantly greater yields than plants in plots covered with blue plastic and brown paper mulches. Soil pesticides significantly increased yields over the non-fumigated control, and, averaged across main plots, DD-MENCS = DD-MENCS + carbofuran > carbofuran + sodium azide > sodium azide = nontreated check. The effects of film mulch were greatest in the non-fumigated check. Conversely, the effects of soil fumigation were negligible under film mulch and one could be substituted for the other.
Hormones in Pear Seeds I. Levels of Gibberellins, Abscisic Acid, Phaseic Acid, Dihydrophaseic Acid, and Two Metabolites of Dihydrophaseic Acid in Immature Seeds of Pyrus communis L.1
Authors: Martin G. C. , Dennis F. G. , MacMillan J. , Gaskin P. 
Published: August 2022

Abstract
Seeds from ‘Bartlett’ and ‘Winter Nelis’ and ovules from seedless ‘Bartlett’ pears were collected periodically between 25 days after full bloom and harvest. Extracts were analyzed for hormones by combined gas chromatography-mass spectrometry, using the technique of selected ion current monitoring. Levels of 6 gibberellins were low in all samples prior to appreciable embryo growth (25 days after full bloom). Content of gibberellins A17, A25, A45 and a presumed 3β-hydroxy gibberellin A45 rose dramatically during rapid embryo growth between 65 and 85 days after full bloom, while the gibberellin content of embryoless ovules of ‘Bartlett’ did not change during this period. Two unidentified gibberellin-like compounds, one isomeric with gibberellin A25 and the other corresponding to a hydroxy gibberellin A45, were detected 85 days after full bloom. Abscisic acid content was also maximal between 65 and 106 days, ovules of seedless ‘Bartlett’ exhibiting considerably higher concentration than seeds of either cultivar. Levels of 5 abscisic acid metabolites varied with seed type and sampling period. Phaseic acid levels remained low in ‘Bartlett’ seeds and ovules during all developmental stages but increased in ‘Winter Nelis’ seeds at 122 days. Concentration of cis, Trans-dihydrophaseic acid, although low, rose as ‘Winter Nelis’ seeds matured while ovules of seedless ‘Bartlett’ showed no such increase. Levels of 2 metabolites, tentatively identified as trans, trans-dihydrophaseic acid and a hydroxylated derivative of dihydrophaseic acid, varied only slightly with development. A third metabolite, characterized as a keto derivative of dihydrophaseic acid or a hydroxy-derivative of phaseic acid, was present in large quantities in unfertilized ovules during the early period of fruit growth, but increased in seeds only after 65 days. The possible roles of these compounds are discussed in relation to seed, fruit, and flower development.
Abscisic Acid Levels in Seeds of Peach. I. Changes during Maturation and Storage1
Authors: Bonamy P. A. , Dennis F. G. 
Published: August 2022

Abstract
cis, trans-Abscisic acid (ABA) was identified by combined gas chromatography-mass spectrometry (GC-MS) in a partially purified methanol extract of mature seeds of peach (Prunus persica (L.) Batsch). No germination of intact seeds occurred during seed maturation. Germination of excised embryos increased with maturity, but ABA content of embryonic axes and other seed parts was not related to germination potential. Drying and storage of seeds increased both free and bound ABA in the embryonic axes, but did not significantly affect ABA content of other seed portions. Free and bound ABA decreased on imbibition except for free ABA in the seed coat and bound ABA in the embryonic axis, Levels of free and bound ABA paralleled one another, suggesting that although the former may be converted to the latter, bound ABA is not a major source of free ABA.
Abscisic Acid Levels in Seeds of Peach. II. Effects of Stratification Temperature1
Authors: Bonamy P. A. , Dennis F. G. 
Published: August 2022

Abstract
The roles of free and bound abscisic acid (ABA) in the breaking of dormancy in seeds of peach (Prunus persica (L.) Batsch) were investigated. Concentrations were consistently 10- to 100-fold higher in the embryonic axes of seeds than in the seed coats or cotyledons. Free and bound ABA declined 75 to 95% during stratification at both 5° and 20°C, yet only the 5° treatment broke dormancy. Extracts of chilled seeds were less inhibitory to germination of non-dormant seeds than were extracts of non-chilled seeds, but ABA content of the extracts was sufficient to account for only a small part of their biological activity.
Effect of Fertilizer Applications on Yield of Rabbiteye Blueberries1
Authors: Austin M. E. , Brightwell W. T. 
Published: August 2022

Abstract
Rabbiteye blueberries (Vaccinium ashei Reade, cvs. Tifblue and Woodard) were fertilized with various ratios of nutrients for 6 years. ‘Tifblue’ responded to 4–8–8 (4.0 N–3.5 P–6.6 K), 5–10–10 (5.0 N–4.4 P–8.3 K), and cottonseed meal 7–2–2 (7.0N–0.9P–1.7K). ‘Woodard’ did not respond to any fertilizer.
A Seven-Parent Diallel Cross in Onions to Evaluate General and Specific Combining Ability and their Interaction with Years and Locations1
Authors: Hosfield George L. , Vest Grant , Peterson C. E. 
Published: August 2022

Abstract
A diallel analysis was used to estimate combining ability of several traits in onion (Allium cepa L.) and evaluate the importance of interactions of general combining ability (GCA) and specific combining ability (SCA) with locations and years. All possible crosses among 7 inbred lines of diverse origin and known horticultural performance were tested for 2 years at the same 3 locations for yield, maturity, bulb traits, and storage quality. Highly significant differences among crosses were detected for all traits. The partitioning of among-cross variation showed that all GCA main effects were highly significant, and SCA main effects were significant for all traits but ring thickness. Cross × environment interactions were primarily due to the interactions of GCA effects with environments. The GCA × year interaction was significant for bulb firmness and centers/bulb, and the GCA × location interaction was significant for yield. While first-order interactions involved only GCA effects, all traits showed significant second-order interactions of both GCA and SCA with years and locations. Variance components of GCA were predominant for all characters, and ratios of GCA to SCA ranged from 2:1 for centers/bulb to 13:1 for % of storage loss. Variance components of GCA × environmental interactions at all levels and for all traits were always smaller than those for GCA main-effect components. For the traits maturity and % of storage loss, the SCA × year × location component was larger than the SCA component. Correlations of GCA effects between environments suggested that significant interactions of GCA were sometimes due to a 1) change in rank of effects from environment to environment and 2) a change in rank and change in variance.
The Effect of Sampling Date and Daminozide on the Nutrient Composition of ‘McIntosh’ Apple Leaves1
Authors: Himelrick David G. , Pollard James E. 
Published: August 2022

Abstract
The effects of treatment with succinic acid-2,2-dimethylhydrazide (daminozide, SADH) on seasonal nutrient accumulation in leaves of ‘McIntosh’ apple trees (Malus domestica Borkh. cv. McIntosh) were investigated. Leaf samples were collected on 6 dates, from June 18 through August 28, 1973 and on August 28, 1974, from trees treated for 5 and 6 years respectively with daminozide. Foliar concentration of N, P, K, B and Cu decreased during the growing season, while Ca, Mg, Mn, Fe, Zn, Sr and Mo increased. During 1973 the level of foliar Ca was significantly higher at the normal sampling time on August 28, in daminozide-treated trees while Fe was significantly lower in these trees. During 1974, Ca, B, Zn and Sr levels in daminozide-treated trees were significantly higher on the August 28 sampling date, while N was significantly lower. Evidence suggests that changes in foliar nutrient status occur as a result of long term use of daminozide.
Diallel Analysis of Sweet Potatoes for Resistance to Fusarium Wilt1
Authors: Collins W. W. 
Published: August 2022

Abstract
Eight clones of sweet potato Ipomoea batatas L. were evaluated for resistance to the soil-borne pathogen Fusarium oxysporum (Schlecht) f. sp. batatas (Wr.) Snydor & Hanson and their reactions varied from extremely susceptible to extremely resistant. The 8 clones were used as parents in a modified diallel crossing design which generated 24 families each consisting of 10 full-sib clones. These 240 clones were evaluated for Fusarium wilt resistance in a randomized complete block design. They showed a gradation of resistance similar to the parents which is consistent with the theory of a quantitative mode of inheritance for this character. Diallel analysis of the 24 families revealed significant general and specific combining ability effects. Additive variance accounted for 87% of the total genetic variance while dominance variance accounted for only 13%. Broad-sense and narrow-sense heritabilities estimated for individuals and full-sib families from the diallel analysis were consistently greater than 70%. Narrow-sense heritability of individuals using the parent-offspring regression method was 50%. Results indicate that gains in Fusarium wilt resistance should be rapid and substantial in sweet potatoes.
Estimation of Heritability and Combining Ability for Fire Blight Resistance in Pear1
Authors: Bell Richard L. , Janick Jules , Zimmerman Richard H. , van der Zwet T. 
Published: August 2022

Abstract
Heritability estimates for fire blight resistance in pear were obtained by regressing progeny means on midparental phenotypes. Approximately half of the variability in resistance in pear was additive (h2 = 0.52), but there was also evidence for nonadditive genetic effects compatible with a proposed qualitative gene for sensitivity. A method was established to estimate relative average combining ability for fire blight resistance. Progeny means of individual parents were adjusted to the grand progeny mean of 8 intercrossed testers based on common progeny.
Fertility and Irrigation Effects on ‘Temple’ Orange. II. Fruit Quality1
Authors: Koo R. C. J. , Reese R. L. 
Published: August 2022

Abstract
Increased N and K rates resulted in higher acid content in juice of ‘Temple’ orange (Citrus hybrid). P fertilization lowered both soluble solids and acid contents, but the influence on acid was more pronounced as it was reflected in higher soluble solids-acid ratio. High N vs. low N treatment also caused a small but consistent reduction in juice content. Spring irrigation resulted in higher soluble solids content than fall irrigation. N treatments decreased and K treatments increased both fruit size and weight; irrigation treatments showed no consistent trends. High N and spring irrigation treatments caused increased intensity of orange color in rind. Incidence of creased fruit was increased by high N, low K, and spring irrigation treatments. No consistent trends were found in fruit storage decay with grove treatments and the data were significant only in certain years.
Seasonal Sugar Concentration in Two Peach Cultivars Differing in Cold Hardiness1
Authors: Lasheen Aly M. , Chaplin Carl E. 
Published: August 2022

Abstract
Levels of soluble sugars in bark, leaves, leaf buds and flower buds of 2 cultivars of peach (Prunus persica (L.) Batsch) differing in cold hardiness were compared throughout the year. Thirteen sugars — galactose, glucose, fructose, xylose, stachyose, sucrose, raffinose, rhamnose, maltose, trehalose, arabinose, ribose and mannose — were present in measurable and variable concentrations. In general, oligosaccharides accumulated, particularly in the bark, during fall and winter, whereas monosaccharides accumulated during periods of active growth. These data do not show significant differences between the 2 cultivars regarding the accumulation of these sugars and cold hardiness.
Studies on the Mechanism of Fruit Abscission in Apple and Peach1
Authors: Schneider G. W. 
Published: August 2022

Abstract
Translocation of l4C-sucrose from leaf to fruit was measured in ‘Golden Delicious’ and ‘Staymared’ apple (Malus domestica Borkh.) and ‘Redhaven’ peach (Prunus persica (L.) Batsch) following the application of compounds reported to influence fruitlet abscission. Succinic acid-2,2-dimethylhydrazide (daminozide) reduced 14C translocation in both apple cultivars but reduced fruit set only in ‘Golden Delicious’. Ethephon reduced 14C translocation and fruit set of peach. Abscisic acid (ABA) and 2,4-dinitrophenol (DNP) reduced 14C-sucrose translocation in apple. Enclosing apple limbs in black cloth bags reduced fruit set and naphthaleneacetic acid (NAA) increased leaf water potential. One method of preliminary screening of compounds for apple fruit thinning may be based on their effect on 14C-sucrose translocation from foliage to fruit.
Influence of Nitrogen Form on Exudation Rate, and Ammonium, Amide, and Cation Composition of Xylem Exudate in Tomato1
Authors: Wilcox G. E. , Mitchell C. A. , Hoff J. E. 
Published: August 2022

Abstract
A shift from NO3 to NH4-N nutrition for tomato (Lycopersicon esculentum Mill.) plants resulted in a significant decrease in xylem exudation rate within 15 minutes. Ammonium treatment also decreased Ca and Mg concentration in exudate in the 1.5 to 2.5 hour interval after the shift, whereas free NH4 and amides increased in the same period. Potassium ion concentration did not change in the time interval from 15 minutes to 7 days following the change of N form. Reduced exudate concentration or reduced exudation rate resulted in large decreases in the total amount of K, Ca, and Mg delivered in the presence of NH4 relative to that of NO3, and offers a possible explanation for the observed deficiencies of these cations in shoot tissues of plants under conditions of NH4 toxicity.
Combining Ability of Three Lycopersicon Species for Resistance to Corynebacterium michiganense1
Authors: de Jong Jan , Honma S. 
Published: August 2022

Abstract
Estimates of heritability and general and specific combining ability for resistance of tomato to Corynebacterium michiganense (E. F. Sm.) H. L. Jens, were made, using a half diallel with 6 parental entries. Both the general and the specific combining abilities of the parents differed. Additive variation accounted for 74% (narrow sense heritability) of the total variation, suggesting that a large part of the observed variation is fixable in true-breeding strains.
Variations in Susceptibility of Apple Stems to Attack by Pine Voles1
Authors: Byers R. E. , Cummins James N. 
Published: August 2022

Abstract
Caged feeding tests of 77 Malus clones, representing 15 species and hybrid species, revealed 9 cultivars apparently less susceptible to feeding by pine voles than ‘Golden Delicious’. Malus X sublobata PI 286613 shoots were attacked least; other cultivars of special promise include ‘Charlotte’, ‘Hucker No. 1’, ‘N.Y. 11928’, ‘Robusta 5’, ‘Sissipuk’, and ‘Ivory’s Double Vigour’.
Quality and Condition of ‘Delicious’ Apples after Storage at 0°C and Display at Warmer Temperatures1
Authors: Hardenburg R. E. , Anderson R. E. , Finney E. E. 
Published: August 2022

Abstract
Apples (Malus domestica Borkh.) were examined after 0, 2, 4, and 6 months’ storage and after simulated retail display for 1 and 2 weeks at 4.4°, 13°, and 21°C. Apples displayed or marketed at 4.4° for 1 week developed less decay and scald than apples held at 21°, and were crisper, brighter, and about 0.55 kg (1.2 lb.) firmer. Apples softened much faster at 21° soon after harvest than after 4 or 6 months’ storage at 0°C. The sonic firmness index decreased significantly with both storage time and with increases in display temp. Weight losses from bulk apples during 1 week of display at 4.4°, 13°, and 21° averaged 0.2, 0.4, and 1.8%, respectively. The greatest loss of acidity was also at the warmest display temp. Apples displayed at 13° were of a quality and condition intermediate to those held at 4.4° and 21°. Apples stored in CA for 6 months and then displayed 2 weeks at 21° were firmer and more acid, and had a lower respiration rate than those stored in air. Refrigerated display of ‘Delicious’ apples is strongly recommended to retard deterioration and preserve their good quality and shelf life.
Response of Young ‘d’Anjou’ Pear Trees to Triazine and Triazole Herbicides and Nitrogen1
Authors: Raese J. Thomas 
Published: August 2022

Abstract
Weed control and supplemental N markedly increased vigor and yield of pear trees (Pyrus communis L. cv. d’Anjou). Under conditions of low soil N, simazine enhanced N uptake. Consequently, simazine increased tree vigor, leaf N, shoot growth, and fruit size in the absence of supplemental N. Fruit from the control (no N or simazine) treatment was denser, yellower, higher in soluble solids, and had less scald and rot than fruit from trees treated with simazine but no N. Amitrole plus simazine (A + S) produced the highest yield in trees receiving no N, and resulted in as much tree vigor as the other treatments with supplemental N. The data suggest that certain triazine and triazole herbicides may partially substitute for N fertilizer on young ’d’Anjou’ trees.
Comparison of Continuous and Alternating Bulb Temperature Treatments on Growth and Flowering in Lilium longiflorum Thunb.1
Authors: Roh Seung Moon , Wilkins Harold F. 
Published: August 2022

Abstract
Optimum temperatures for rapid shoot emergence from non-cooled bulbs was a constant 12.8°C with ‘Ace’ and ‘Nellie White’ lilies. Twenty-four hour cycles of 1.7°/12.8°C delayed shoot emergence of both cultivars.
Using 115 days from shoot emergence to flowering as a standard, 6 weeks of 24 hour cyclic temperature treatments of 1.7°/12.8°C produced more flower buds in ‘Ace’ than did 1.7°/7.2° or 7.2°/1.7° treatments. In ‘Nellie White’ constant 1.7°, 1.7°/12.8°, or 12.8°/1.7° temperature treatments produced more flower buds than 1.7°/7.2° or 7.2°/1.7° treatment. Leaf number and plant height were not affected by alternating temperature treatments.
With ‘Nellie White’ an intercalation of 3 weeks at 15.6°C temperature treatment to bulbs after 1, 2, or 3 weeks of 4.4°C increased secondary flower bud (development) when compared to a continuous 4.4°C bulb treatment for 5 or 6 weeks. No differences in days to flower from potting and in plant height were obtained among the various temperature treatments in both ‘Ace’ and ‘Nellie White’. Increases in total flower bud number were due to the increases in the secondary bud number.
Effect of Seed Quality and Seed Treatment on Yield of Pea (Pisum sativum L.)1
Authors: Short G. E. , Loria R. , Lacy M. L. 
Published: August 2022

Abstract
‘Miragreen’ garden pea seeds from individual seed lots were sorted into bleached, partially-bleached, and non-bleached categories. Seeds were either soaked for 48 hours in aerated water at 22°C, coated with thiram fungicide, or received no treatment. Seeds were planted in Conover loam soil where damping-off and seedling rot were primarily caused by Pythium ultimum Trow and Fusarium solani (Mort.) Sacc f. sp. pisi (Jones) Snyd. & Hans. No differences in germination in vitro were found among bleached, partially bleached, and non-bleached seeds. However, seedling emergence in the field was greater from untreated non-bleached seeds (69%) than from untreated bleached seeds (30%); emergence from partially bleached seeds (58%) was intermediate. Regardless of degree of bleaching, all seedlings were a normal green color after emergence, and appeared equal in vigor. Pea yields from untreated bleached seeds were less than from untreated non-bleached seeds, apparently because pea-emergence damping off was so much greater with bleached than with non-bleached seeds. No yield differences occurred with fungicide-treated seeds. Soaking partially bleached seeds for 48 hours in aerated water at 22°C prior to planting in April was as effective in improving emergence in artificially infested soil as coating seeds with thiram. However, when seeds were planted in mid-June, the thiram treatment gave higher seedling emergence than the soaking treatment. In general, high yields were achieved by early planting of seeds and minimum root rot.
Air and Soil Temperature Effects on Flowering of Citrus1
Authors: Hall Anthony E. , Khairi Mohamed M. A. , Asbell Charles W. 
Published: August 2022

Abstract
Interactive effects of air and soil temperature on flowering of 4- and 12-year-old ‘Frost Valencia’ orange [Citrus sinensis (L.) Osbeck] budded on trifoliate orange rootstocks [Poncirus trifoliata (L.) Raf.] were determined in controlled environments. Quiescent trees were subjected to 1 of 4 environmental treatments consisting of 2 day-night air temperature regimes in 2 glasshouses and 2 constant soil temperatures in each house. Total bud break was increased by warm soils (25°C) compared with cool soils (15°). In contrast, the initiation of flowers on the new shoots was mainly influenced by air temperature, with more flowers in cooler air (20/15°, day/night) than at temperatures of 30/15°. Lower air temperature, however, resulted in more leafless floral shoots while the greatest number of leafy floral shoots was produced with both warmer soil and higher air temperature.
Variance Components and Heritability of Nut and Kernel Traits in Almond1
Authors: Kester D. E. , Hansche P. E. , Beres V. , Asay R. N. 
Published: August 2022

Abstract
Means and variance components were estimated for genotype, environment (year), and genotype-year interactions for 28 nut and kernel traits of almond (Prunus amygdalus Batsch). The analysis involved over 2,500 genotypes and 20 years of observations. Estimates of heritability were obtained for 19 traits. The latter analysis involved some 100 families. The genetic component of variance and heritabilities tended to be large for shell type, size, shape, double kernels, bitterness, and crease. Year and genotype-year effects were large for quality factors such as shell and kernel color, callus, shriveling, pubescence, grade, blanks, smoothness, gumminess, and broken and split kernels.