bluuebunny/crossref_metadata_2025_split huggingface dataset:
Embryogenesis and Plantlet Regeneration from Callus of Hibiscus acetosella1
Authors: Reynolds B. D. , Blackmon W. J. 
Published: August 2022

Abstract
Plantlets have been produced by germination of somatic embryos derived from callus of Hibiscus acetosella Welw. ex. Hiern. Five of the media used were based on Nitsch and Nitsch's Medium H (purchased formulated without IAA or sucrose). To this base were added, per liter: 40 g glucose for NH; 10 g sucrose for NH-1; 40 g sucrose, 1 mg 2,4-dichlorophenoxyacetic acid (2,4-D), and 1 mg 6-furfurylaminopurine (kinetin) for RM-1; 40 g glucose, 250 mg NaH2PO4·H2O, 28 mg FeC6H5O7·nH2O, 100 mg i-inositol, 30 mg adenine, 0.1 mg (2-chloroethyl)trimethylammonium chloride (chlormequat), and 4 mg 2,4-D for SEM-1; and 40 g glucose, 0.1 mg chlormequat, 0.05 mg B-napthoxyacetic acid (NOA), and 10 mg 2-isopentyladenine (2iP) for HC. The B5 medium was Gamborg's B5 without 2,4-D. All media contained 8 g agar and had the pH adjusted to 5.7 prior to autoclaving. Primary explants placed on HC produced adventitious shoots and callus. When callus explants from HC or primary explants of roots were placed on RM-1, a callus containing embryoid-like structures was produced. Torpedo stage embryos were induced by subculturing this callus from RM-1 on SEM-1 and could be proliferated by sequential transfer from SEM-1 to RM-1, then back to SEM-1. When callus containing torpedo-stage embryos was transferred to B5, the embryos germinated and produced rudimentary plantlets with elongated hypocotyls, short roots, and small cotyledons. These developed into plants when transferred to NH-1.
Root Temperature, Water Relations, and Cold Hardiness in Two Citrus Rootstocks1
Authors: Wilcox Darlene A. , Davies Frederick S. , Buchanan David W. 
Published: August 2022

Abstract
The influence of root temperature on whole-plant water relations and cold hardiness in seedlings of 2 citrus rootstocks—rough lemon (Citrus jambhiri Lush.) and Carrizo citrange [C. sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.]—and ‘Valencia’ scions on both rootstocks was examined. Plants were exposed to root temperatures of 5°, 10°, or 15°C for 5–8 weeks, while shoots were exposed to a nonacclimating air temperature of 30°. Root temperatures of 5° decreased leaf xylem water potential and increased cold hardiness. Statistical differences in diffusive resistance and transpiration were observed only at the 5° root temperature. Root temperature did not significantly alter leaf relative water content in either seedlings or budded plants. A decrease in soil and root temperature alone, without a simultaneous reduction in air temperature, can provide an effective cold-acclimating environment for citrus.
Changes in Indoleacetic Acid, Abscisic Acid, Gibberellins, and Cytokinins during Budbreak in Pecan1
Authors: Wood B. W. 
Published: August 2022

Abstract
The dynamics of indoleacetic acid (IAA), cis-trans abscisic acid (c,t-ABA), and gibberellin (GA)- and cytokinin-like compounds were measured in pecan [Carya illinoensis (Wang) K. Koch; cv. Desirable] buds following their release from imposed dormancy. Both bound and free ABA levels in apical and basal primary buds and in secondary buds declined 27 days prior to budbreak until the time of budbreak, with the exception of a steady rise in free ABA in secondary buds. During this period IAA initially dropped sharply, remained low, and finally increased again at budbreak. Cytokinin-like substances peaked after the drop in IAA but prior to the peak in gibberellin-like substances which occurred during bud swelling. The findings raise the possibility of a key regulatory role for IAA, possibly through its influence on regulation of bud cytokinin and gibberellin levels via their metabolism in roots. Growth regulator dynamics during pecan budbreak are discussed in relation to the hormonal theory versus tissue sensitivity to growth regulators.
Effects of Anaerobic Nitrogen and Carbon Dioxide Atmospheres on Ethanol Production and Postharvest Quality of Blueberries
Authors: Saltveit Mikal E. , Ballinger Walter E. 
Published: August 2022

Abstract
The ethanol content of ‘Harrison’ and ‘Jersey’ highbush (Vaccinium corymbosum L.) and ‘Premier’ rabbiteye blueberries (V. ashei Reade) increased linearly with time (1 to 4 hours) and exponentially with temperature (0° to 30°C) during exposure to an atmosphere of pure N2 or CO2. CO2 production was depressed about 20% under N2 gas. Berries which were placed in air after 4 hours in CO2 lost half the CO2 they contained every 30 minutes. After 3 hours, CO2 evolution from treated and control fruit was the same. Fruit quality was unaffected by exposure at 0° to 30° to pure N2 or CO2 gas for up to 4 hours. However, 22 hours in a CO2 atmosphere at either 0° or 30° reduced fruit quality. An equation was derived to calculate ethanol accumulation under different cooling rates.
Photographic Analysis of Cucumber Fruit Elongation
Authors: Wehner Todd C. , Saltveit Mikal E. 
Published: August 2022

Abstract
Growth patterns of cucumbers (Cucumis sativus L.) were studied by photographing developing fruit at 2- or 3-day intervals over a 30-day period beginning with pollination (day 0). Nine cultivars were studied: ‘Chinese Long Green’, ‘Sprint 440’, ‘Marketmore 76’, and ‘Minisol’ (all fresh-market types); ‘Riesenschal’ (a schälgurken type); and ‘Marbel’, ‘Kobus’, ‘Calypso’, and ‘Wisconsin SMR-18’ (all pickling types). Analysis of the photographs showed that all sections of the fruit grew in length at a constant rate during the 30-day period. The pattern of growth was fairly uniform, except that there was slightly more growth in the center section than at the ends, and slightly more growth at the blossom end than at the peduncle end of the fruit. Fresh-market and schälgurken types had the longest fruit over the 30-day period of growth, but pickling types had the highest percent change in length. Pickling types produced shorter fruit because they stopped growing earlier than the two other types (12 vs. 14 days, respectively).
Fertilizer and Plant Density Effects on Yield Performance and Leaf Nutrient Concentration of Bush Snap Beans
Authors: Mack H.J. 
Published: August 2022

Abstract
There were no significant fertilizer x plant-density interactions affecting yields or leaf nutrient concentrations of snap beans (Phaseolus vulgaris L.) in 5 field experiments. Higher rates of fertilizer application produced significantly higher yields of pods than did lower rates in 2 experiments. At higher plant densities (15.2- to 30.5-cm rows, 43 to 65 plants/m2) yields were 20% to 38% higher than at lower plant densities (91.4-cm rows, 22 to 29 plants/m2). Average yield increase at higher densities was 29%. Crop economic values followed similar trends. At higher plant densities, average N, K, Ca, and Mg concentrations in leaves at early bloom were lower than at lower densities. Higher fertilizer rates tended to increase N concentration in leaves but had no consistent effects on P, K, Ca, and Mg.
Effect of Gibberellic Acid on Yield and Quality of Fall-harvested and Overwintered Spinach
Authors: Gonzalez Alfredo R. , Marx David B. 
Published: August 2022

Abstract
A single application of 20 ppm gibberellic acid (GA3) 2 weeks before harvest increased yields and height of fall spinach (Spinacia oleracea L.) by inducing the setting of leaves in an upright position and stimulating petiole and stem growth. Small differences were noted between GA3-treated and untreated overwintered spinach. Cultivars responded similarly to growth conditions and to GA3 application. Both GA3-treated and untreated fall spinach had better quality than overwintered spinach harvested in the spring. Spinach treated with GA3 had higher shearpress values, yellow and green color, lower titratable acidity, and no change in pH values as compared to the control. A panel graded GA3-treated spinach slightly higher in amount of petioles and stems and lower in general acceptability than the untreated control. Better utilization of GA3 was obtained in the fall-grown spinach.
Development of Flowers and Changes in Carbon Dioxide, Ethylene, and Various Sugars of Cut Zinnia elegans Jacq.
Authors: Stimart Dennis P. , Brown Dennis J. , Solomos Theophanes 
Published: August 2022

Abstract
Postharvest flower fresh weight of Zinnia elegans Jacq. increased when held in solutions containing 200 mg liter-1 8-hydroxyquinoline citrate (8-HQC) and sucrose and decreased when held in deionized water. Ethylene biosynthesis was enhanced by holding flowers in solutions of 8-HQC + 1, 2% or 3% sucrose compared with deionized water where ethylene release was low initially and remained low. Carbon dioxide evolution declined sharply the first 2 days postharvest and remained low for flowers held in deionized water, but remained at initial levels for those held in 200 mg liter-1 8-HQC + 3% sucrose. Glucose, fructose, and sucrose in ray florets declined to levels barely detectable if flowers were held in deionized water but increased if held in 200 mg liter-1 8-HQC + 3% sucrose. The induction of ethylene biogenesis may be an injury response caused by sucrose.
Variation in Wound Response among Cultivars of Red Maple
Authors: Gallagher Peter W. , Davis Sydnor T. 
Published: August 2022

Abstract
Wound closure and growth data were determined over a 2-year period for 12 cultivars of red maple (Acer rubrum L.) and branch and trunk wounds were analyzed for extent of associated discolored wood. A cultivar effect was noted in both closure and compartmentalization rates. ‘Armstrong’, ‘Doric’, ‘Gerling’, and ‘October Glory’ exhibited below average closure rates; ‘Schlesinger’, ‘Autumn Flame’, and ‘Autumn Glory’ had a more rapid closure rate in response to wounding. ‘Red Sunset’ and ‘Schlesinger’ were above average and ‘Bowhall’ and ‘Scanlon’ were below average in capacity to compartmentalize wounds. Previous years' twig extension growth was a good prediction of a plant's ability to close wounds. Higher nutrient levels of callus were associated with higher closure rates.
Sources and Nature of Resistance to Downy Mildew and Turnip Mosaic in Chinese Cabbage
Authors: Niu Xin-ke , Leung Hei , Williams Paul H. 
Published: August 2022

Abstract
Forty-six Chinese cabbage [Brassica campestris spp. pekinensis (Lour) Olsson] lines consisting of open-pollinated cultivars, inbreds, and F1 hybrids from China were screened for seedling resistance to downy mildew (Peronospora parasitica) (Pers.) Ex. Fr. Thirty-seven lines of this collection were screened for turnip mosaic resistance. Five lines showed dual resistance to downy mildew and turnip mosaic. Resistance to downy mildew at the cotyledon stage, expressed as a reduction in the sporulation capacity of P. parasitica, was under dominant monogenic control. Turnip mosaic resistance was expressed as a hypersensitive reaction. Genetic analysis of a cross between turnip mosaic resistant and susceptible parents suggested that resistance was conditioned by 2 dominant genes.
Mycorrhizal Infection and Growth of Onion in the Field in Relation to Phosphorus and Water Availability
Authors: Bolgiano N.C. , Safir G.R. , Warncke D.D. 
Published: August 2022

Abstract
Vesicular-arbuscular (VA) mycorrhizal colonization of onion (Allium cepa L.) roots was found at high levels in commercially used soils only when P concentrations were below 30 µg/cm3. Soils sampled were muck soils with varying amounts of organic matter and sand and marl soils, and the P range was 10-250 µg/cm3. Onions were also seeded in 2 fields of Houghton muck soil, at 4 P levels, with and without inoculum of Glomus etunicatus Becker & Gerdemann. High colonization occurred when soil P concentrations were below 15-20 µg/cm3. High yields and high colonization past midseason were achieved simultaneously upon the addition of 30 kg/ha P. In a separate experiment, onions were grown at 3 P levels and 2 watering regimes. The P concentrations associated with limited mycorrhizal root colonization shifted from 15 to 30 µg/cm3 with a decrease in water availability. The results demonstrate the need for control of soil water conditions, as well as P, when attempting to utilize VA mycorrhizae.
Yield Components and Pod Quality of Snap Beans Grown under Differential Irrigation
Authors: Bonanno A. Richard , Mack Harry J. 
Published: August 2022

Abstract
Field experiments were conducted to evaluate the effects of differential irrigation treatments on the yield and pod quality of ‘Oregon 1604’ and ‘Galamor’ snap beans (Phaseolus vulgaris L.) in 1981 and 1982. Treatments in which various levels of positive canopy minus air temperature differences [stress-degree-days (SDD)] accumulated between irrigations were evaluated along with irrigation at 4 growth stages, a dry treatment which received only one irrigation to establish plants, and a control treatment irrigated at -0.06 MPa soil water potential (SWP). In both seasons, yield was related strongly to the average soil water potential from planting to harvest. Yields in 1982 were at least 5 MT/ha greater at a given average soil water potential than in 1981. Yields of ‘Oregon 1604’ and ‘Galamor’ were similar under adequate irrigation, but under greatest water stress, yield of ‘Oregon 1604’ was higher than for ‘Galamor’. Pod number was reduced only in the dry treatment. Percentage of set pods, pod length, and number of seeds per pod were all reduced by low irrigation, while fiber content of pods and weight per seed were increased by low irrigation.
Calcium-related Leaf Necrosis of Seedling Carrots
Authors: Tibbitts T.W. , Setiamihardja R. , Palzkill D.P. , Olszyk D.M. 
Published: August 2022

Abstract
Seedlings of carrot (Daucus carota L.) develop leaf necrosis when subjected to conditions which encourage rapid growth in controlled-environmental chambers. Necrosis occurred on the 4th and 9th developing leaves and was apparent as they unfolded. Injury was determined to be calcium-related, since foliar CaCl2 applications reduced injury and covering the plants during the dark period to promote translocation of Ca by root pressure flow stopped injury completely. Young unfolding leaves in covered plants had 50% greater Ca concentrations than those plants maintained in the chamber without covering. Carrot cultivars had different degrees of sensitivity to the leaf necrosis with ‘Red Core Chantenay’ > ‘Danvers’ > ‘Carousel’ > ‘Scarlet Nantes’.
Selection for Improved Low Temperature Germination in Cucumber
Authors: Nienhuis J. , Lower R.L. , Staub J.E. 
Published: August 2022

Abstract
Recurrent half-sib selection within a heterogeneous population of cucumber (Cucumis sativus L.) was effective in improving germination at 15°C from 34.4% in cycle 0 to 92.4% in cycle 3. The linear regression coefficient indicated an average increase of 19.8% units per cycle of selection. Correlated responses to selection resulted in increased percentage of germination at 20° and 25° and decreased days to germination at 15°, 20°, and 25°.
Yield Response of Major Pod-bearing Nodes in Bush Snap Beans to Irrigation and Plant Population
Authors: Mauk Craighton S. , Breen Patrick J. , Mack Harry J. 
Published: August 2022

Abstract
Yield variables of mainstem nodes 6 (terminal) and 2 (that of the first trifoliate leaf) of ‘Oregon 1604’(Phaseolus vulgaris L.) were evaluated at 2 irrigation regimes × 2 plant populations in a warm (1978) and a moderate (1979) season. A single inflorescence formed at node 6, whereas up to 4 inflorescences were borne on branches at node 2. After emergence, crops were irrigated either when the soil water potential reached −0.06 MPa (high) or −0.25 MPa (low). High and low plant populations were, respectively, 45 vs. 18 plants/m2 in 1978 and 54 vs. 33 plants/m2 in 1979. Yield per unit area was increased significantly from 38–54% by high plant population and 40–120% by high irrigation. On a per plant basis, plant population failed to have a significant effect on total yield or yield variables at node 6. At node 2, however, high plant population reduced the number of inflorescences in 1978 and decreased the number of flowers, number of pods formed and harvested, and percentage set and reduced pod yield by about 50% in both years. Per unit area yields of node 2 at high and low plant population differed by less than 13–18%. Since the productivity of node 6 was not influenced by density, per unit area yields at this node more directly reflected plant population. Nodes 2 and 6 responded similarly to the low irrigation regime, which in 1978 significantly decreased the number of pods formed, percentage set, and pod yield at both nodes. Irrigation effects on individual yield parameters at each node generally were less in the cooler 1979 season. No significant irrigation–plant population interactions occurred for any measured yield variable in either season.
Calculating Heat Units via a Sine Function
Authors: Logan Samuel H. , Boyland Patricia B. 
Published: August 2022

Abstract
The concept of heat units (degree days) has provided a basis for several studies to analyze the time between planting and maturity for plants. The model reported here utilizes a sine function to approximate the behavior of temperatures during the day. The available heat units for the day then are obtained by integrating the sine function given constraints of the plant growth process as reported by other authors. These constraints include: 1) a minimum temperature below which plant growth stops; 2) a high temperature above which plant growth remains unchanged for some interval up to a maximum temperature; and 3) a maximum high temperature above which plant growth is retarded. The model is developed explicitly for tomato (Lycopersicon escutentum Mill.).
Inheritance, Linkage, and Gene Interaction Studies in Lettuce
Authors: Ryder Edward J. 
Published: August 2022

Abstract
Two new lettuce genes are described and named: chlorophyll deficient-2 (cd-2) and Early flowering (Ef). Brown pericarp is either a pleiotropic effect of plump involucre (pl) or is caused by a closely linked gene. White pericarp (w) is epistatic to brown. Endive-like leaf (en) and white pericarp are linked, with P = 0.47. Virescent (vi) and fringe (fr) are linked, with a recombination value of p = 0.25. Genes for spininess and anthocyanin color are linked. Endive, white, virescent, fringe, and male sterile-6 (ms-6) form a linkage group. Three other double recessives have interactive relationships. Endive and fringe together are phenotypically extreme endive; virescent and golden (go) together are golden; golden and chlorophyll deficient-2 are golden and partially lethal.
Factors Affecting in Vitro Embryogenesis from Undeveloped Ovules of Mature Citrus Fruit
Authors: Moore G. A. 
Published: August 2022

Abstract
The effects of genotype and growth additives on the induction of embryogenesis from undeveloped ovules from mature fruit of Citrus were examined. Embryos were produced in cultures of 15 of the 17 representative polyembryonic cultivars examined. Cultured ovules of 5 monoembryonic cultivars did not become embryogenic. Percentages of ovules producing embryos in the responsive polyembryonic cultivars ranged from 5 to 20 after 56 days in culture. Mean numbers of embryos per responsive ovule ranged from 1.9 to 13.2. Effects of growth additives on the production of embryos from undeveloped ovules from mature fruit of ‘Marsh’ grapefruit were tested. A low concentration (0.01 mg/liter) of butanedioic acid mono (2, 2-dimethylhydrazide) (daminozide) was most effective at increasing the induction of somatic embryogenesis over the control treatment of 500 mg/liter malt extract. The presence of abscisic acid or a higher concentration of malt extract (100 mg/liter) in the medium also increased embryo induction, but germination of embryos obtained on the malt extract medium was poor. The use of undeveloped ovules from mature fruits allows the initiation of embryogenic cultures from a wide range of Citrus species.
Relationship between Resistance to Severe and Type Strains of Bean Yellow Mosaic Virus
Authors: Tatchell S. P. , Baggett J. R. , Hampton R. O. 
Published: August 2022

Abstract
The inheritance of resistance in beans (Phaseolus vulgaris L.) to typical bean yellow mosaic virus (BYMV) was compared to the severe strain (BYMV-S). When F3 families of BYMV resistant ‘Great Northern UI 31’ (GN31) × susceptible ‘Dwarf Horticultural’ were tested for resistance to each virus strain, occurrence of homozygous resistant families was conditioned by 3 recessive genes for BYMV and 2 recessive genes for BYMV-S. Of the 132 families tested, 122 were susceptible to both BYMV and BYMV-S, 6 were resistant to BYMV-S and susceptible to BYMV, 4 were susceptible to BYMV-S and resistant to BYMV, and none were resistant to both. This ratio closely fits a theoretical 945:63:15:1, indicating that resistance to BYMV and to BYMV-S are inheritied independently. When GN31 was crossed with breeding line Sl-5, also resistant to both virus strains, F3 progenies included families susceptible to one or both virus strains, possibly through the complimentary interaction of modifiers. Chi square tests indicated independent inheritance of resistances to BYMV and BYMV-S in GN31 × S1-5 progenies.
Photoperiod and Soil Temperature Effects on Crop Productivity Efficiency and Growth of Seedling Geraniums in the Greenhouse
Authors: Merritt Richard H. , Kohl Harry C. 
Published: August 2022

Abstract
Geranium seedlings (Pelargonium × hortorum L.H. Bailey, ‘Mustang’) grown in 13 hr photoperiods were 23% taller due to stem and petiole elongation, had larger leaves, and prior to canopy closure had a higher crop productivity efficiency (CPE) than seedlings grown under 9 hr photoperiods. In general, the tallest plants were produced when grown with soil temperatures of 18°C. The highest weekly CPE attained was 3.8%.
Studies of de Novo Flower Initiation from Thin Cell Layers of Tobacco
Authors: Bridgen Mark P. , Veilleux Richard E. 
Published: August 2022

Abstract
The potential for in vitro floral photoinduction of epidermal and subepidermal thin cell layers (TCLs) taken from the short-day plant Nicotiana tabacum L. ‘Maryland Mammoth’, the long-day plant Nicotiana sylvestris L., and the day-neutral plant Nicotiana tabacum L. ‘Samsun’, in both the floral and vegetative states, was examined. Whether cultured under long days (16 hr) or short (8 hr), only TCLs from the flowering day-neutral species flowered in vitro. These were termed responsive TCLs. TCLs from photoperiodic plants yielded only vegetative buds; these were termed nonresponsive. Vegetative bud formation in nonflowering TCLs generally was greater than in flowering TCLs but did not approach the number of flower buds on flowering TCLs. In vitro grafts of responsive TCLs to nonresponsive TCLs resulted in flowering only in the responsive portion, regardless of the position of the graft. Just as the nonresponsive TCLs were not induced to flower by some graft-transmissible substance, responsive TCLS were not inhibited from flowering when grafted to nonresponsive TCLs.