bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photomorphogenic Responses of Strawberry to Photoperiodic and Photosynthetic Radiation
Authors: Maas John L. , Cathey Henry M. 
Published: August 2022

Abstract
The effects of supplemental light provided by high- and low-pressure sodium (HPS and LPS), metal halide (MH), and incandescent filament (INC) lamps were determined on the photomorphogenic responses of strawberry (Fragaria × ananassa Duch.) plants. Supplemental light was provided in the greenhouse under normal winter conditions of 9–12 hr of daylight in Beltsville, Md. Growth responses of representative Junebearer (‘Badgerbelle’), everbearer (‘Our Own’), and day-neutral (‘Tribute’) plants propagated by tissue culture (TC) and conventional means (RP) were recorded under supplemental lighting compared to natural day length (ND) conditions and with long days simulated by ND supplemented with a daily 4-hr night interruption (NI) with 0.9 W·m–2 (400–850 nm) INC exposure (ND and NI) at 2200–0200 hr. Vegetative and reproductive responses to supplemental lighting varied with the photoperiod class of the cultivar and with its mode of propagation. Vegetative growth (stolon and daughter plant development) of Junebearer RP and both Junebearer and everbearer TC plants was promoted by all supplemental light treatments. Supplemental light did not promote growth of everbearer RP plants or day-neutral TC or RP plants. Crown branching of day-neutral TC plants was promoted by several treatments, but the number of crowns on RP plants was increased only under LPS at 12 W·m–2 for 24 hr. Flower truss initiation of Junebearer plants was not stimulated by supplemental light treatments compared to ND. Everbearer RP plants produced more flower trusses under supplemental light treatments compared to ND, but TC plants were stimulated only by LPS at 12 and 24 W·m-2 for 24 hr. Day-neutral RP plants produced more flowers per truss under most treatments compared to ND, but TC plants produced the greatest number of flowers per truss under MH at 12 W·m-2 for 24 hr.
Recurrent Selection for Resistance to White Mold in Phaseolus Species
Authors: Lyons M.E. , Dickson M.H. , Hunter J.E. 
Published: August 2022

Abstract
Recurrent selection was used to breed Phaseolus species for resistance to white mold disease, caused by Sclerotinia sclerotiorum. Twenty diverse genotypes selected for resistance to white mold formed the cycle 0 population. These lines were intercrossed in a partial diallel, and the F2 progeny were tested for resistance to white mold using a detached blossom/ascospore technique. Twenty single-plant selections were made, and the F3 progeny of these selections formed the cycle 1 population. A 2nd cycle of intercrossing, evaluation, and selection was completed, and genetic gain was determined by evaluating disease resistance of the selfed progeny derived from the cycle 0, 1, and 2 populations. There was a highly significant linear improvement in mean disease response from cycle 0 to cycle 2. When a subjective rating was used to assess disease response, the average gain/cycle was 0.52 rating units, and the percentage gain from cycle 0 to cycle 2 was 31%. When measurement of lesion length (centimeters) on the main stem was used to assess disease response, the average gain/cycle was 1.96 cm, and the percentage gain from cycle 0 to cycle 2 was 50%. The results of this study indicate that recurrent selection may be a useful technique for the development of resistance to white mold in Phaseolus species.
Seed Hydration Treatments For Improved Sweet Corn Germination and Stand Establishment
Authors: Bennett Mark A. , Waters Luther 
Published: August 2022

Abstract
This research examines the potential of seed hydration for improving sweet corn (Zea mays L.) seed performance, especially for plantings in cool (10°–15°C) soils. In addition to the effect of hydration treatments, the influence of seed quality and cultivar was evaluated using electrolyte leakage tests and seedling growth cold tests. Seed hydration treatments included seed hardening (a wetting/drying cycle), seed moisturizing (placing seed in moist vermiculite), and osmoconditioning, which were compared to a dry seed control. Hardening and moisturizing treatments improved early emergence by as much as 20%, while osmoconditioning significantly lowered field emergence. Seed moisturizing and hardening also improved uniformity of emergence, and reduced the number of days required to attain 50% or 75% emergence. Seed hydration treatments were effective with the three levels (high, medium, and low) of seed quality and the three cultivars (‘Jubilee’, ‘Midway’, and ‘Reward’) studied.
Onion Responses to Various Salinity Levels
Authors: Wannamaker Mary Jo , Pike Leonard M. 
Published: August 2022

Abstract
Onion growth responses to salinity levels were evaluated using five onion cultivars. In a plant growth study, eight salt levels were used with electrical conductivities (EC) ranging from 0.8 to 12.0 dS·m−1. Total area of the leaves and stem, dry weight, plant height, and leaf tip burn were measured after 45 days of growth. All five cultivars were sensitive to low salt levels, with significant reduction occurring at 1.4 dS·m−1. In a 2nd experiment germination percentage was evaluated for 8 days; a wider range of salt levels was tested (0.0–50.0 dS·m−1). Rate of germination was retarded 1–3 days with increasing salt concentrations, but germination percentage after 8 days was not significantly reduced in the 0.0–25.0 dS·m−1 salt levels. Germination was prevented at 45.0 dS·m−1 for all cultivars except ‘Texas Grano 1015Y’, which exhibited slight germination. These test results confirm that salt effects during germination are not related to later responses of the whole plant to salt. Screening onion for salt tolerance would best be done at the vegetative stage.
Seasonal Development of Highbush Blueberry Roots Under Sawdust Mulch
Authors: Abbott John D. , Gough R.E. 
Published: August 2022

Abstract
Annual growth of white unsuberized roots from mature ‘Earliblue’, ‘Bluecrop’, and ‘Lateblue’ blueberry (Vaccinium corymbosum L.) plants relative to soil temperatures, shoot growth, and stage of development was studied for 3 years. The growth of roots continued throughout the year, but was much reduced at soil temperatures below 8°C. Two peaks in the growth of roots occurred, the first in early June and the 2nd, higher peak in September. Both peaks in root growth occurred with soil temperatures of 14° to 18°. The growth rate declined at soil temperatures outside this range. Growth of roots was concomitant with shoot growth.
Nonbacterial Ice Nucleation in Peach Shoots
Authors: Anderson J.A. , Ashworth E.N. , Davis G.A. 
Published: August 2022

Abstract
Experiments were conducted to determine the relative contributions of bacterial and nonbacterial ice nuclei to freezing of peach [Prunus persica (L.) Batsch] shoots. Exposure to 33°C for 3 hr eliminated bacterial ice nuclei active at −3° on inoculated shoot pieces, but controls were not affected. In another experiment, ice nucleation temperatures and ice nucleation-active (INA) bacterial populations of field-collected shoots were determined. Mean freezing temperatures of 20 g (fresh weight) shoots were not significantly different in the presence or absence of INA bacteria (detection limit of 10 cells/g fresh weight). INA bacteria were detected on 19% of the shoots with a maximum natural population of 180 cells/g fresh weight. Inoculation studies indicated that 20 g fresh weight peach shoots contained a mean of 1.0 nonbacterial (−3°) ice nuclei, while shoots with 180 INA cells/g fresh weight averaged 1.4 (−3°) ice nuclei per 20 g. Most ice nuclei active at −3° were of nonbacterial origin.
Induction of Intumescence Injury on Leaf Disks
Authors: Morrow Robert C. , Tibbitts Theodore W. 
Published: August 2022

Abstract
A procedure for inducing intumescence injury (oedema) on leaf disks was developed using a species of wild tomato, Lycopersicon hirsutum PI LA 1625. This procedure used Plexiglas vessels with which various combinations of irradiance direction and leaf disk orientation could be studied. Disks (1.4 cm in diameter) were cut from leaves and floated on distilled water in these vessels. Irradiation was provided by cool-white fluorescent lamps and was filtered through ultraviolet- (UV) absorbing Plexiglas. Disks were scored for injury after a period of 72 hr. Intumescences that developed on leaf disks using this procedure appeared similar in size, shape, and coloration to those on intact plants. Disks taken from leaves that were almost fully expanded developed injury most consistently, and the adaxial disk surface was much more sensitive to this injury than the abaxial surface. Intumescences were generally greater on the disk surface in contact with water. Besides L. hirsutum, injury was induced successfully on disks cut from eucalyptus (Eucalyptus globulus), sweet potato (Ipomoea batatas), tomato (Lycopersicon esculentum), ivy geranium (Pelargonium peltatum), European aspen (Populus tremula), and white potato (Solanum tuberosum).
Growth of ‘Thompson Seedless’ Grapevines: I. Leaf Area Development and Dry Weight Distribution
Authors: Williams Larry E. 
Published: August 2022

Abstract
Data were collected over 3 years to provide detailed information on growth and development of ‘Thompson Seedless’ grapevines used for raisin production. Leaf area and leaf, shoot, and cluster dry weights were measured throughout the growing season. Results were plotted against growing degree days (GDDs), using a minimum temperature threshold of 10°C, after budbreak. There was a linear increase in leaf area and vegetative dry matter from about 200 to 1000 GDDs after budbreak. Cluster dry weight increased linearly from 750 GDDs after budbreak until harvest. While shoot numbers per vine increased 70% from 1983 to 1985, there was not a similiar increase in the amount of dry matter per vine. Weight per unit leaf area (WL) increased from ≈ 40 g·m-2 early in the season to >65 g·m-2 90 days after fruit harvest. Results indicate that vines in this vineyard maintained a constant growth pattern year after year when growth was plotted vs. growing degree days.
Influence of Leaf to Fruit Ratios and Nutrient Sprays on Fruiting, Mineral Elements, and Carbohydrates of Apple Trees
Authors: Ferree David C. , Cahoon Garth A. 
Published: August 2022

Abstract
For 5 years, the leaf to fruit ratios of mature ‘Golden Delicious’ (Malus domestica Borkh.) apple trees on M.9 rootstock with declining leaf N levels and fruit size were adjusted to low, medium, or high levels of leaves per fruit, 2 weeks after bloom, coupled with 8 weekly foliar sprays of urea, phosphorus-potassium-sulfur (PKS), or urea plus PKS beginning at pink. No interaction occurred between the leaf : fruit ratios and foliar sprays. Mean leaf N over 5 years was slightly reduced when the crop was adjusted to high numbers of leaves: fruit and increased by urea or PKS foliar sprays. The only effect of adjustment in leaf: fruit ratio or foliar nutrients on nonstructural carbohydrate (NSC) levels was an increase in leaf NSC in 1978-1980. As the number of leaves per fruit increased, the percentage of the total harvest in the larger size classes increased with corresponding decrease in the smaller size classes. Total yield per tree, fruit firmness, and russeting were not influenced by adjusting the leaf : fruit ratio, while soluble solids were increased and fruit color decreased at the high level of leaves per fruit. Foliar urea sprays increased the percentage of fruit in the largest size class, yield per tree, fruit firmness, soluble solids, color, and the amount of russet.
Physiological and Quality Responses of Brussels Sprouts to Storage in Controlled Atmospheres
Authors: Lipton Werner J. , Mackey Bruce E. 
Published: August 2022

Abstract
Brussels sprouts (Brassica oleracea L., Group gemmifera) were stored 2, 3, or 4 weeks at 2.5°, 5°, or 7.5°C with 0.5%, 1%, 2%, 4%, or 21% O2, or in the following combinations of % O2/%CO2: 1/10, 2/10, or 20/10. Storage was followed by 2 or 3 days of aeration at 10°. Low O2 levels reduced the rate of CO2 production relative to that in air, but rates were similar among the low O2 levels. Ethylene production was low at 2.5° and 5° in all atmospheres, but at 7.5° it was 20% to 170% higher in air than in low O2. Ethylene production was virtually stopped during exposure to high CO2, but increased dramatically during aeration. Since low O2 levels retarded yellowing and 10% CO2 retarded decay development, the combinations of low O2/high CO2 effectively extended the storage life of the sprouts at 5° and 7.5°. The beneficial effect of CA storage was still evident after return of the samples to normal air. The sprouts retained good appearance for 4 weeks at 2.5° whether stored in CA or in air. Storage in 0.5% O2 occasionally induced a reddish-tan discoloration of the heart leaves and frequently an extremely bitter flavor in the nongreen portion of the sprouts. None of the atmosphere modifications appreciably affected either the tissue pH or texture of the sprouts.
Refreshed Delayed Light Emission and Fluorescence for Detecting Pretreatment Effects on Chilling Injury in Coleus
Authors: Abbott Judith A. , Krizek Donald T. , Semeniuk Peter , Moline Harold E. , Mirecki Roman M. 
Published: August 2022

Abstract
Intact plants of a green-leafed strain of Coleus blumei Benth. (PI 354190) were exposed to 5°C for 48 or 72 hr after pretreatment for 48 hr at two levels of photosynthetic photon flux (PPF) (8 or 320 μmol·s−1·m‒2) at two temperatures (13° or 20°). Plants were sprayed with two abscisic acid (ABA) levels (0 or 200 g·m‒3) either 0 or 48 hr before chilling. Postchilling condition of the plants was assessed by comparing the time courses of refreshed (cyclically excited and measured) delayed light emission (RDLE) and fluorescence (FLU) from dark-equilibrated leaves. Greater suppression of RDLE and FLU indicates greater injury. Plants pretreated at 8 μmol·s−1·m‒2 PPF showed less suppression of RDLE and FLU, contained more chlorophyll, and showed less injury than did plants pretreated at 320 μmol·s−1·m‒2 PPF. Increasing the duration of chilling from 48 to 72 hr reduced the maximum RDLE and FLU slightly. Pretreatment temperatures and ABA concentration had negligible effects on RDLE and FLU levels. The maximum RDLE, the RDLE level at 7.5 sec, the maximum FLU, the FLU at 1.5 sec, and variable FLU were the measurement variables most responsive to individual and combined treatment effects. Maximum RDLE from upper leaf surfaces was the measurement most responsive to the combined effects of all treatments. Chemical name used: [S-(Z,E)]-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2,4-pentadienoic acid [abscisic acid (ABA)].
Histogenic Instability in Tissue Culture-proliferated Strawberry Plants
Authors: Marcotrigiano Michael , Morgan Pamela A. , Swartz Harry J. , Ruth Jennifer 
Published: August 2022

Abstract
A phenotypic and sexual analysis of Fragaria vesca ‘Albo-Marginata’ determined that the leaf variegation was of chimeral origin. Stable periclinal chimeras were established in vitro from runner tips. Plants were transferred to proliferation media containing 0.5 μm IBA, 0.3 μm GA3, and BA at either 0, 1.3, 4.4, or 13.2 μm. Whereas the histogens of field-grown runner plants remained stable, more than 90% of the plantlets propagated in vitro varied from the original explants. Most variants were albino or were green, but some were mericlinal chimeras. Histological evidence indicated that many shoots were adventitious, arising from basal callus tissue or petioles. Chemical names used: 1H-indole-3-butanoic acid (IBA); gibberellic acid (GA3); N-(phenylmethyl)-1H-purin-6-amine (BA).
Influence of Photoperiod, Apical Meristem, and Explant Orientation on Axillary Shoot Proliferation of Apple Cultivars in Vitro
Authors: Yae Byeong Woo , Zimmerman Richard H. , Fordham Ingrid , Ko Kwang Chool 
Published: August 2022

Abstract
The apple (Malus domestica Borkh.) cultivars Empire, McIntosh, Delicious, Triple Red Delicious, and Vermont Spur Delicious were grown on Linsmaier and Skoog (LS) medium containing 4.4 μm BA, 0.5 μm IBA, 1.3 μm GA3, 87.6 mm sucrose, and 7 g·liter−1 Difco Bacto-agar. All cultivars produced significantly more total shoots and shoots >1 cm (usable shoots) on a 16-hr compared to a 24-hr photoperiod. Removing the apical meristem significantly increased both the total and usable shoots only for ‘Triple Red Delicious’. Placing explants horizontally on the medium significantly increased the number of total and usable shoots for all cultivars except ‘McIntosh’. Internode length was significantly reduced for ‘Delicious’, ‘Triple Red Delicious’, and ‘Vermont Spur Delicious’ and increased for ‘Empire’ on 24-hr photoperiods. Chemical names used: N-(phenylmethyl)-1H-purin-6-amine (BA); 1H-indole-3-butanoic acid (IBA); gibberellic acid (GA3).
Pollen Viability in Five Southeastern United States Diploid Species of Vaccinium
Authors: Megalos B.S. , Ballington J.R. 
Published: August 2022

Abstract
Five southeastern United States diploid Vaccinium species were examined in 1983 and 1984 for pollen viability, unreduced pollen frequency, and pollen diameter. Significant intraspecific variation occurred for all three characteristics. Pollen viability and 2n pollen frequency did not vary significantly among species or between years. The number of clones producing 2n pollen was low, 8 of 41 in 1983 and 3 of 41 in 1984. Vaccinium elliottii Chapm. accounted for at least half of the 2n clones each year and also exhibited the highest unreduced pollen frequencies in 1983 (1.9%) and 1984 (1.6%). All 1984 2n clones were diplandrous the previous year, suggesting a genetic basis for unreduced gamete production. Unreduced pollen was found in three of the five species studied. Pollen diameter was not a good criterion for distinguishing one diploid species from another. Significant pollen diameter differences from 1983 to 1984 may be attributable to differences in pollen storage procedures and not environment per se.
Temperature, Grafting Method, and Rootstock Influence on Iron-deficiency Chlorosis of Bean
Authors: Zaiter H.Z. , Coyne D.P. , Clark R.B. 
Published: August 2022

Abstract
Two resistant (Great Northern ‘Emerson’ and Neb-WM1-83-10) and two susceptible (PI 165078 and ‘Steuben Yellow Eye’) cultivars/lines of dry bean (Phaseolus vulgaris L.) to iron (Fe) deficiency chlorosis, and their reciprocal graft combinations (two methods) were grown in pots in Tripp sandy clay loam (coarse-silty, mixed, mesic Aridic Haplustoll) known to induce Fe deficiency chlorosis. Experiments were conducted in a growth chamber under low (24°/13°C) and high (29.5°/18.5°) air temperature regimes at 15/9 hr (light/dark) periods. The experimental plan was a split-plot with temperature regimes as main plot and treatments in a completely randomized design with two replications. When scions of entries susceptible to Fe deficiency were grafted onto rootstocks of resistant entries, the leaves of the grafted plants were greener than the ungrafted susceptible entries. In reciprocal combinations, the leaves of scions of the resistant entries became chlorotic. These data indicate that rootstocks of dry beans appear to control chlorosis resistance, presumably due to root uptake or translocation of Fe. The chlorosis was more severe on leaves of cleft-grafted-scions than with approach-grafted-scions and more severe under the low compared to high temperature regimes.
An Agrometeorological Model for Assessing the Effect of Heat Stress During the Flowering and Early Fruit Set on Avocado Yields
Authors: Lomas J. 
Published: August 2022

Abstract
An agrometeorological model was developed for assessing the effect of heat stress during flowering and early fruit set on avocado (Persea americana Mill) yields. This model accounted for heat stress only and was considered to occur when the daily maximum temperature was ≥33°C. In addition to the daily maximum temperature, the model considered the duration of such temperatures in days, as well as the timing of the occurrences of such temperatures in relation to the flowering and early fruit set of ‘Fuerte’ avocado. The specifications of the climatic data inputs are based on experimental results in the temperature range of 33° to 43°C extrapolated linearly. A series of weighting factors were used for the duration of heat spells in days. In the temperature range of 33° to 35° the weighting was n − 1; for the 36° to 38° range, 1.4n; and for the 39° to 43°C range, 2.0n. Weighting factors for the timing of the occurrence of heat spells follow closely the near-normal percentage distribution curve of open flowers. At bud burst in March, the weighting is 0.4, increasing to 1.3 at early fruit set by mid-May and decreasing rapidly to 0.3 by the end of June. The functional relationship between the model heat stress output and the yield of avocado for an irrigated, high-yielding plantation shows fairly good correlation, r2 = 0.42 to 0.51, depending on the statistical method used. The agreement between the heat stress index and the yield of avocados is closely related only during those years when the plantation is subject to heat stress indexes greater than 10. Testing the model on independent data commenced in 1985 and includes a yield memory term.
Effects of Growth Regulator Sprays and Notching on Growth and Branching of ‘Starkrimson Delicious’ Apple Trees
Authors: Greene Duane W. , Miller Paul 
Published: August 2022

Abstract
A block of 2-year-old ‘Starkrimson Delicious’ apple (Malus domestica Borkh.) trees growing in Somerville, Victoria, Australia were treated with 0 to 500 ppm BA when terminal growth was 2 cm. BA application initially increased the rate of lateral shoot growth. However, the growth rate rapidly slowed and extension growth on the lateral shoots stopped earlier than on untreated trees. There was a linear increase in the number of lateral shoots and a linear reduction in the length of these lateral shoots as the concentration of BA was increased. BA forced more lateral shoots to grow at the tip of the branch than at the base, although shoots at the base of the limbs grew longer. A reduced concentration of BA was required to stimulate spurs to grow out into lateral shoots on the vigorous, more upright central leader. Lateral shoots were longer on the central leader than on the scaffold branches, indicating tree and/or branch vigor may be a major factor in producing good scaffold limb development following BA application. Notching forced more spurs to form lateral shoots on the central leader, and these shoots grew longer than those on the scaffold limbs. Notching increased the number of buds developing into lateral shoots following BA application. May and Baker 25-105 increased the number of lateral shoots on a tree. This result occurred both on untreated trees and on those that previously received 400 ppm BA. Reducing the number of lateral shoots by pinching apices of shoots soon after BA application was the most effective method to increase the length of BA-induced lateral shoots. Chemical names used: N-(phenylmethyl)-1H-purine-6-amine (BA) (2-chloroethyl)phosphonic acid (ethephon), butanedioic acid mono(2,2-diemthylhydrazide) (daminozide), propyl 3-t-butylphenoxyacetate (May and Baker 25-105).