bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetics and Linkage Analysis of 19 Isozyme Loci in Apple
Authors: Weeden N.F. , Lamb R.C. 
Published: August 2022

Abstract
The polymorphism in nine enzyme systems in apple (Malus domestica Borkh.) was analyzed using horizontal starch gel electrophoresis. The systems studied included aspartate aminotransferase, diaphorase, glucosephosphate isomerase, isocitrate dehydrogenase, phosphoglucomutase, and triosephosphate isomerase. The products of at least 27 loci could be distinguished in these systems, 19 of which displayed polymorphism. Joint segregation analysis in populations derived from crosses between highly heterozygous cultivars revealed four multilocus linkage groups: Aat-c–Idh-1, Dia-2–Mdh-4, Gpi-c2-Aat–p, and (Dia-5, Pgm-p1)–(Mdh-2, Tpi-c2). Although several of the populations investigated had been prescreened for resistance to apple scab, cedar-apple rust, or fire blight, no correlation could be established between the inheritance of an allozyme and a resistant phenotype. The high frequency of duplicate loci encountered is in accordance with the postulated tetraploid nature of the genome.
Isozyme Banding Patterns and Their Usefulness as Genetic Markers in Peach
Authors: Durham R.E. , Moore G.A. , Sherman W.B. 
Published: August 2022

Abstract
The usefulness of isozyme banding patterns as genetic markers in peach [Prunus persica L. (Batsch)] was investigated using starch gel electrophoresis. Samples for electrophoresis included leaves of both juvenile and mature plants. A survey of 38 enzyme activity stains and five electrophoretic buffer systems was conducted. Only 12 staining systems produced well-resolved banding patterns; of these, nine were monomorphic among all genotypes surveyed and three showed some variation. Genetic analysis of the variable banding patterns observed for diaphorase, malate dehydrogenase, and peroxidase revealed the presence of single independently inherited loci, designated Dia-1, Mdh-1, and Per-1. These loci are inherited in a simple Mendelian manner and are useful as genetic markers in peach. Some possible applications to peach breeding are discussed.
Crossability of BC1 Aneuploid and Tetraploid Progeny Derived from Vaccinium ashei/corymbosum Pentaploid Hybrids
Authors: Vorsa Nicholi , Jelenkovic Gojko , Draper Arlen D. , Galletta Gene J. 
Published: August 2022

Abstract
V. corymbosum L./V. ashei Reade pentaploid blueberry hybrids backcrossed to tetraploid V. corymbosum yield tetraploids and aneuploids. Six BC1 derivatives, a tetraploid (2n = 4x = 48) and five multiple aneuploids (2n = 4x + 3, 4, 5, 8, and 9 = 51, 52, 53, 56, and 57) were selfed, intercrossed, and backcrossed to the V. corymbosum cv. Bluecrop. The fertility parameters measured were percent fruit set (FS), total seeds/berry (TS), developed seeds/berry (DS), percent developed seeds/berry (PDS), percent seed germination (PG), and number of seedlings (NS). Values of all parameters decreased as aneuploidy level of the cross (sum of extra chromosomes, number of chromosomes over 2n = 48, in the seed and pollen parent) increased; the relationship was principally linear. A significant quadratic relationship was noted for PDS. Diallel analysis revealed that reciprocal effects were significant for all parameters except PG and were the second most important factor contributing to variability among crosses for NS. All parameters indicated a high level of self sterility. Although the aneuploids in this study had reduced crossability, they can produce sizable progenies with practical efficiency. Contrary to previous reports, these results suggest that pentaploid hybrids and their BC1 derivatives can be used to facilitate gene transfer from V. ashei into V. corymbosum.
Growth Response and Weed Control in Slicing Cucumbers Under Row Covers
Authors: Hemphill Delbert D. , Crabtree Garvin D. 
Published: August 2022

Abstract
Five weed-control treatments (unweeded; hand-weeded; bensulide and naptalam; bensulide, naptalam, and paraquat; black polyethylene mulch) were combined factorially with three row-cover treatments (no cover, spun-bonded polyester, highly perforated polyethylene) in a 2-year experiment. Slicing cucumbers (Cucumis sativus L.) were transplanted 26 (1985) or 23 (1986) days after application of the bensulide-naptalam. This combination of herbicides provided weed control for up to 4 weeks after transplanting, but was less effective in 1986 than in 1985. Row covers reduced herbicide efficacy. Spraying paraquat through the covers 2 to 3 days before setting transplants significantly improved weed control and cucumber yield. Soil crusting was reduced, and earliness and total yield were enhanced by mulch and row covers. Greatest yields and estimated net economic return in both years occurred with row covers with mulch followed by mulch alone in 1986 and by mulch alone or hand-weeding with row covers in 1985. Weed control, earliness, and yield were not affected significantly by type of row cover in either year. Chemical names used: O,O-bis(1-methylethyl)-S-[2-(phenylsulfonyl)amino]ethyl]phosphorodithioate (bensulide); 2-[(1-napthalenylamino)carbonyl]benzoic acid (naptalam); 1,1′-dimethyl-4,4′-bipyridinium salts (paraquat).
Growth of Foliage Plants in Differentially Compacted Potting Media
Authors: Conover C.A. , Poole R.T. 
Published: August 2022

Abstract
Six potting media (Metro Mix 200, 300, 350, 500, 2 sedge peatmoss : 1 pine bark : 1 cypress shavings (by volume) and 3 sedge peatmoss : 1 mason sand (v/v) were compacted at 0, 0.1, 0.2, or 0.3 kg·cm−2. Noncapillary pore space was reduced in all media at 0.1 kg·cm−2 as compared to 0 pressure, but increasing compaction pressure had more effect on 2:1:1 than on 3:1 or Metro Mixes. Pilea pubescens Liebm. ‘Silver Tree’ and Dracaena sanderana Hort. Sander ex M. T. Mast. were used in two additional experiments where the six media were combined factorially with compaction pressures of 0.1 and 0.2 kg·cm−2 and irrigation rates of two or four applications/week. Both genera were affected more by potting media and irrigation levels than by compaction, with best plants generally produced in Metro Mixes receiving the higher irrigation level.
Outcrossing Rates in Pecan and the Potential for Increased Yields
Authors: Marquard Robert D. 
Published: August 2022

Abstract
Nuts produced from controlled crosses of ‘Western’ pecan [Carya illinoensis (Wangenh.) C. Koch] pollinated with ‘Wichita’ were 20% heavier and 12% larger by volume than self-pollinated nuts. The inherited biochemical marker of malate dehydrogenase was used to quantify outcrossing in a ‘Western’ orchard with ‘Wichita’ as the pollinator. The frequency of cross-pollination declined with distance from the pollinator, and the linear equation y = 53.9 − 6.1x was derived to estimate percent cross-pollination (y) in row (x) away from the pollinator. A model to estimate relative orchard production predicts maximum efficiency of a ‘Western’ orchard when the frequency of the pollinator is 25% to 33%. Nut quality of ‘Western’ field samples was positively related to percent cross-pollination of the sample. Cross-pollination under field conditions of ‘Western’ by ‘Wichita’ increased nut weight and volume 31% and 16%, respectively.
Tomato Polygalacturonase Elicits Ethylene Production in Tomato Fruit
Authors: Baldwin E.A. , Pressey R. 
Published: August 2022

Abstract
Fungal cell-wall lysing enzymes have been shown to induce ethylene production in different plant systems. The effect of endogenous plant cell-wall lysing enzymes on ethylene synthesis in fruit has received only limited attention. Therefore, tomato fruit (Lycopersicon esculentum, Mill.) were vacuum–infiltrated with the tomato cell-wall enzymes, polygalacturonase I and II (PG I, PG II) and pectinmethylesterase (PME). Fruit ethylene levels were observed to increase relative to either salt, buffer, or boiled enzyme controls. This increase in ethylene production occurred in green ‘Cherry’ tomato fruit as well as in the mutants rin, nor, and Cornell 111. Enzyme-induced ethylene synthesis generally peaked at or before 17 to 20 hr and decreased to lower or basal levels in most immature normal cultivars by 42 hr after treatment. Ethylene was maintained at high levels, however, in some (possibly more mature) green fruit, as well as in all mutant lines. PG II was more effective than PG I in inducing ethylene production and PME seemed to enhance the ethylene-inducing activity of PG II.
Plant Production from Longitudinally Halved Storage Roots of Two Sweet Potato Cultivars
Authors: Hall Melvin R. 
Published: August 2022

Abstract
Initiation of sweet potato [Ipomoea batatas (L.)] plant harvests from the propagating bed was later from the sparse plant producer ‘Georgia Jet’ than from the profuse plant producer ‘Georgia Red’. Also, the initiation of plant harvests from storage roots cut into longitudinal halves for inspection of internal quality before bedding was later than from whole roots. These differences were reflected in lower cumulative percentages of total plants harvested from ‘Georgia Jet’ than from ‘Georgia Red’ within 2 weeks and from longitudinal halves within 2 and 4 weeks after initiation of plant harvests. Total plant production was greater from whole than from halved ‘Georgia Jet’ roots. Total plant production was greater from halved roots immersed in Botran 75W compared to those immersed in calcium hypochlorite. Cutting and immersion treatments did not influence total plant production from ‘Georgia Red’, a profuse plant producer. ‘Georgia Jet’ roots deteriorated more than ‘Georgia Red’ in the propagating bed, and deterioration was increased by cutting and immersion in calcium hypochlorite. Presprouting did not reduce deterioration of roots in the propagating bed, but did reduce the number of days from bedding until first plant harvest. It also increased the cumulative percentage of the total plants harvested within 2 and 4 weeks after harvests were initiated and increased total number of plants produced from both small and large ‘Georgia Jet’ roots and from large ‘Georgia Red’ roots. Large roots of each cultivar produced more plants than were produced by small roots when presprouted. Large roots of ‘Georgia Jet’ also produced more plants than were produced by small roots when not presprouted, but root size did not influence total plant production from ‘Georgia Red’ roots that were not presprouted. Chemical name used: 2,6-dichloro-4-nitroaniline (Botran 75W).
Internal Ethylene Concentration of ‘McIntosh’, ‘Northern Spy’, ‘Empire’, ‘Mutsu’, and ‘Idared’ Apples During the Harvest Season
Authors: Chu C.L. 
Published: August 2022

Abstract
Five cultivars of apples (Malus domesticus Borkh.) were sampled weekly during the harvest season for 3 consecutive years. The ethylene concentrations in the atmosphere from the apple core cavities were measured using a gas chromatograph. Each cultivar exhibited an individual range of internal ethylene concentration over the harvest season. Depending on the cultivar, the rate of increase in internal ethylene concentration varied from year to year. A single ethylene concentration cannot be used to estimate harvest maturity. Cultivar characteristics of internal ethylene concentrations and their yearly variation are two significant factors in interpreting ethylene measurements used for maturity estimations.
Stomatal and Cuticular Water Loss from Apple, Cherry, and Sweetgum Plants After Removal from in Vitro Culture
Authors: Sutter Ellen 
Published: August 2022

Abstract
The relative contributions of stomatal and cuticular water loss to desiccation of tissue-cultured apple (Malus domestica Borkh), cherry (Prunus avium × P. pseudocerasus), and sweetgum (Liquidambar styraciflua L.) leaves after removal from culture were studied. Conductance from both abaxial and adaxial leaf surfaces was measured on plants immediately after removal from culture, after acclimatization, and after being subjected to water stress. In all species, stomatal conductance decreased significantly after acclimatization. Cuticular conductance was significant under some conditions and may have been due to damage resulting from tissue dehydration. The three species had quite different responses to imposed water stress. Responses appeared to be related to differences in stomatal functioning, cuticular integrity, and degree of acclimatization.
Nature of the Semihard Seed Characteristic in Snap Beans
Authors: Holubowicz R. , Taylor A.G. , Goffinet M.C. , Dickson M.H. 
Published: August 2022

Abstract
During imbibition, water always follows the same pattern when entering the seed testa in semihard seeds (SHS) of snap bean (Phaseolus vulgaris L.). Water first enters the raphe and the chalazal region of the testa (R-CT), then migrates circumferentially along the midline of the seed, leaving the lateral faces the last to be fully imbibed. The R-CT region is the main site of primary uptake of both water vapor and liquid water by SHS. The hilum, micropyle, and strophiole play only a minor role in water uptake in SHS. In comparison to the readily permeable seeds of ‘Bush Blue Lake 47’, SHS have more total phenols in the osteosclereid cells and more pectic substances in the palisade cells of the CT. The presence of these compounds may account for the impermeable nature of SHS. Measurements made of palisade cell length and width in the R-CT region revealed that cell length increased and width decreased in the chalazal testa region (CT) as seed moisture content increased from 6% to 12%. It is proposed that semihardening of bean seeds is mainly a result of the reversible physical changes in the length and width of the palisade cells in the R-CT region. Seeds imbibe at high moisture content (12%) because the palisade cells have stretched, which allows water uptake. Seeds are impermeable at low moisture content (6%) because the palisade cells change in size and form a physical barrier to water movement.
Factors Affecting in Vitro Shoot Proliferation of French Tarragon
Authors: Mackay W.A. , Kitto S.L. 
Published: August 2022

Abstract
Optimum proliferation of French tarragon (Artemisia dracunculus L. var. sativa) shoot tips was obtained on Murashige and Skoog salts and vitamins supplemented with 1.8 μM BA, 0.3 μM NAA, and 3% sucrose. Proliferation was maximal after 4 weeks of culture. Proliferation was increased with unpinched shoot tips placed horizontally on the medium. Significantly greater proliferation of shoot tips occurred on medium gelled with Gelrite than with washed Difco Bacto-agar. Medium was gelled with Gelrite (0.5, 1.0, 1.5, 2.0, 2.5, or 3.0 g·liter−1) or washed Difco Bacto-agar (2.0, 4.0, 6.0, 8.0, 10.0, or 12.0 g·liter−1). Increasing concentrations of both gelling agents decreased proliferation. Stock plant pretreatment (natural daylength or 24-hr supplemental light) did not increase proliferation in vitro. Container size had an effect on shoot proliferation, with shoots in 55 × 70 mm jars having significantly greater axillary shoot length than those in 25 × 150 mm culture tubes or 90 × 95 mm jars and significantly greater number of axillary shoots than those in 25 × 150 mm culture tubes. Long-term subculture of shoots on agar-gelled medium (4 g·liter−1) resulted in greater proliferation than those cultured on medium gelled with Gelrite (1.5 g·liter−1). Rooting was maximized by placing cuttings >10 mm in length, derived from shoots proliferated on agar-gelled medium, in clear plastic containers in the laboratory. A 5-sec dip of the basal portion of the cuttings in either NAA (537, 2685, or 5370 μM) or IBA (490, 2450, or 4990 μM) increased rooting percentage and root numbers. Chemical names used: N-(phenylmethyl)-1H-purin-6-amine (BA); 1-naphthaleneacetic acid (NAA); l-H-indole-3-butyric acid (IBA).
Response of American Ginseng to Foliar Applications of 2,4-D
Authors: Konsler T.R. , Monaco T.J. , Sheets T.J. , Leidy R.B. 
Published: August 2022

Abstract
Single and multiple applications of 2,4-D to American ginseng (Panax quinquefolium L.) with fully expanded leaves during a 3-year period caused no visible injury to foliage or roots. During the final 2 years of the study, percent plant survival was greater with two applications per year than with one, and percent gain in root weight decreased with increased rate of application of the herbicide. Also, terminal weight of roots decreased with increased number of years of herbicide application. Treated plants did not differ from nontreated plants in percent survival, final root weight, or percent gain in root weight. Herbicide residue was not detected (<0.02 ppm) in roots from plants that received multiple applications of the three highest 2,4-D dosages: 0.56, 1.12, or 2.24 kg·ha−1 a.i. Foliar residues were detected in plants treated once or twice per year for 3 years with 0.56 or 1.12 kg·ha−1 a.i. 2,4-D. Chemical name used: (2,4-dichlorophenoxy)acetic acid (2,4-D).
Evaluation of Nutrient Deficiency and Micronutrient Toxicity Symptoms in Florists’ Hydrangea
Authors: Bailey Douglas A. , Hammer P. Allen 
Published: August 2022

Abstract
Nutrient imbalances were investigated to a) document nutrient deficiency and micronutrient toxicity symptoms in florists’ hydrangea (Hydrangea macrophylla Thunb.) and b) examine the possible relationship of single-element deficiencies and toxicities with a foliar malformation prevelant on hydrangeas grown at >30°C. Plants subjected to N, P, K, Ca, Mg, S, B, Fe, and Zn deficiency and B and Mn toxicity treatments produced visual symptoms of the corresponding nutrient imbalance. Visual symptoms did not develop in +Fe, +Cu, +Zn, +Mo, −Mn, −Cu, and −Mo treatments. None of the symptoms induced were similar to the foliar malformations observed on hydrangeas grown at >30°. Hydrangea leaf malformation does not appear to be correlated with any single nutrient imbalance within hydrangea leaves. Results of the nutrient deficiency and toxicity experiments offer a diagnostic tool for interpretation of nutrient analysis of hydrangea.
Electrolyte Leakage, Firmness, and Scanning Electron Microscopic Studies of Watermelon Fruit Treated with Ethylene
Authors: Elkashif Mohamed E. , Huber Donald J. 
Published: August 2022

Abstract
Studies were conducted to investigate the influence of 50 μl·liter−1 ethylene on the cell wall, polygalacturonase (PG) activity, and electrolyte leakage of harvested watermelon [Citrullus lanatus (thunb) Matsum and Nakai] fruit. Electrolyte leakage was significantly increased in tissues from ethylene-treated fruit. The highest leakage occurred in distilled water, although the net effect of ethylene was less dramatic due to high leakage from control fruit. Leakage was greatly reduced but the ethylene effect more apparent compared to the control when tissues were incubated in an isotonic medium of mannitol or in isotonic medium containing CaCl2. Polygalacturonase activity increased markedly in ethylene-treated fruit, showing a > 10-fold rise during the first 6 days of treatment. Little change in PG activity occurred in melons stored in air, even in fruit stored for as long as 120 days. Cell walls of fruit exposed to ethylene exhibited acute ultrastructural damage. The decline in placental tissue firmness and the development of watersoaking symptoms observed by the third day of 50 μl·liter−1 ethylene treatment were apparently due, in part, to the PG-mediated cell wall breakdown resulting in cell rupture. Additionally, ethylene appeared to enhance membrane permeability.
Ranking Tissue Mineral Analyses to Identify Mineral Limitations on Quality in Fruit
Authors: Fallahi Esmaeil , Righetti Timothy L. , Raese J. Thomas 
Published: August 2022

Abstract
A diagnostic procedure was developed to identify mineral limitations on pome fruit quality. Fruit mineral levels were useful only when developed on a ranked or percentile (0 to 100) basis. Therefore, procedures were developed using percentile values for both leaf and fruit mineral concentration. An individual can decide which quality parameters are important and whether minimum, maximum, or intermediate values for these quality parameters are most desirable. Multiple regression is used to predict relative rankings for each qualify parameter. A simple sorting program allows the operator to use these rankings to choose which categories of fruit are undesirable. It is then possible to select from among remaining lots those likely to contain fruit having the poststorage quality factors the operator considers most important. The approach is demonstrated with 2 years of data from a high-density ‘Starkspur Golden Delicious’ apple orchard. Selections of fruit with the best poststorage quality were based on mineral content, assuming that maximum firmness, soluble solids, titratable acidity, and yellow color were considered as most desirable. Further ranking evaluations were obtained by evaluating 6 years of data relating quality in ‘d’Anjou’ pears with fruit mineral concentrations. A ranking approach allows meaningful interpretation despite large differences in fruit mineral concentrations reported for different locations and years by a range of analytical laboratories. The procedure is flexible, and fruit could be categorized successfully according to several definitions of optimum quality.
Relationships of Plant Density and Harvest Index to Seed Yield and Quality in Carrot
Authors: Oliva Ruben N. , Tissaoui Tahar , Bradford Kent J. 
Published: August 2022

Abstract
Carrot (Daucus carota L. cv. Danvers) seed were produced at plant spacings of 0.05, 0.10, 0.20, and 0.30 m in 0.80-m rows to give populations of 25, 13, 6, and 4 plants/m2. Samples from the adjacent commercial carrot seed field provided an additional density of 36 plants/m2. Seed yield, harvest index, and seed quality were evaluated with respect to umbel order and plant density. Phenological development was unaffected by plant density, but plant height increased significantly as density increased. The number of umbels per plant and the number of seeds per umbel decreased with increasing plant density, while seed weight was unaffected. The proportion of the seed contributed by primary umbels increased from 20% at the lowest to 60% at the highest density. Seed yield per plant declined continuously as population increased, but seed yield per unit area increased to a maximum at 12 plants/m2, then declined. Total biological yield (above-ground biomass) rose to a plateau level with increasing plant population. Ceiling biological yield coincided with maximum seed yield. Seed quality within each umbel order, assessed by germination percentage and rate, seedling growth, embryo length, and abnormal or embryoless seeds, was unaffected by plant density, but consistently decreased from primary to tertiary umbel orders. Harvest index (seed yield/biological yield) was highly correlated with seed quality. The relationship between harvest index and plant density in carrot seed production may be useful in optimizing plant populations for maximum seed yield and quality.
Tomato Response to Trickle Irrigation and Black Polyethylene Mulch
Authors: Bhella H.S. 
Published: August 2022

Abstract
A 2-year field study was conducted on a fine sandy loam soil near Vincennes, Ind., to evaluate tomato (Lycopersicon esculentum Mill. cv. Sunny) response to trickle irrigation and black polyethylene mulch. Use of trickle irrigation resulted in higher petiole P and B and lower Zn concentrations than using no irrigation. Trickle-irrigated soils had lower soil NH4-N, NO3-N, and K and higher Mg concentrations than non-irrigated soils. Soil NH4-N, NO3-N, and Mg concentrations were higher in soils mulched with polyethylene than in soils without mulch. The use of trickle irrigation increased plant height, whereas polyethylene mulch increased plant spread and dry matter production. Early, late, and total yields were improved with all trickle irrigation and polyethylene mulch treatments. Total yields were 66%, 70%, and 123% greater for plants grown with polyethylene mulch, trickle irrigation, and polyethylene mulch plus trickle irrigation, respectively, than control plants.