bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paclobutrazol Suppresses Shoot Growth and Influences Nut Quality and Yield of Young Pecan Trees
Authors: Wood Bruce W. 
Published: August 2022

Abstract
Paclobutrazol (PBZ) was applied in one or more formulations as a basal trunk drench (0, 19, 38, 76, 152 mg·cm−2 trunk cross-sectional area) or orchard floor application (0, 52, 104, and 208 mg·cm−2 trunk cross-sectional area) to 3- and 10-year-old pecan [Carya illinoensis (Wangenh.)C. Koch] trees. Vegetative growth was highly sensitive to PBZ for at least 3 to 4 years after a single treatment. There were no differences due to formulation for any of the parameters evaluated. Shoot growth and production of in-shell nuts were negatively related in a curvilinear manner to PBZ rate. Nut size increased the first two seasons after treatment, and yield efficiency increased curvilinearly with PBZ rate. Excessive vigor of Iammas shoots coincided with the cessation of vegetative growth inhibition by PBZ. There was a differential cultivar response in nut yield for 3-year-oid ‘Cheyenne’ and ‘Desirable’ trees; however, there was no cultivar differences in 10-year-old trees of ‘Shoshoni’, ‘Desirable’, and ‘Cape Fear’. Use of PBZ appears to allow for the manipulation of tree size of young pecan trees. Chemical names used: β-[(4-chlorophenyl)-ethyl] -α-(1, l-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).
Fall Ethephon Application Increases Peach Flower Bud Resistance To Low-temperature Stress
Authors: Durner Edward F. , Gianfagna Thomas J. 
Published: August 2022

Abstract
Eight-year-old ‘Cresthaven’ peach (Prunus persica L. Batsch.) were sprayed to runoff in mid-October with ethephon and Dormex, two potential bloom-delaying compounds. Flower buds were evaluated for differences in hardiness after field exposure to < −23°C for 4 hr in Jan. 1987. Buds treated with ethephon were significantly hardier than control buds or buds treated with Dormex. Controlled freezing tests just before bloom, continuing through full bloom, indicated the same difference. In addition, ethephon-treated buds had an estimated LT50 of −1.6° at full bloom compared to an estimated LT50 <0°, but greater than −0.5° for controls. Ethephon-treated buds also attained full bloom ≈7 days later than control buds. Yield also was enhanced by ethephon compared to all other treatments. Results confirm the bloom-delaying phenomenon associated with fall ethephon application and also indicate that ethephon increases the intrinsic hardiness of peach flower buds when applied in the fall. Chemical names used: (2-chloroethyl) phosphonic acid (ethephon); calcium cyanamid (Dormex).
Fruiting Affects Photosynthesis and Senescence of Pecan Leaves
Authors: Wood Bruce W. 
Published: August 2022

Abstract
Seasonal measurements of net photosynthesis (Pn), stomatal conductance (Cs), and endogenous senescence-related chemicals were made on pecan [Carya illinoensis (Wang.) C. Koch] trees growing in the orchard environment. Leaves from terminal shoots of mature, 75-year-old ‘Moneymaker’ trees in the “on” alternately bearing phase maintained 10% to 40% higher Pn rates than did those of “off” phase trees. These “on” leaves also maintained higher levels of chlorophyll, protein, amino acids, and RNA, but less K. than “off” leaves. The presence of developing fruit suppressed the rate of late summer and autumnal leaf senescence, with “on” trees retaining their leaves in a higher state of vigor than those of “off” trees. Pn and Cs rates between leaflets of adjacent fruiting and nonfruiting shoots of 7-year-old ‘Desirable’ trees were also 10% to 15% higher for the fruiting shoots throughout the season. Pn and Cs rates were influenced such that gas exchange of leaves increased as sink demand increased. These data provide evidence that this sink-demand associated stimulus operates in a localized rather than a generalized manner and that it retards the rate of leaf senescence.
Effect of Water Deficit on Vegetative Growth and Fruit Development in Jojoba
Authors: Nerd A. , Benzioni A. 
Published: August 2022

Abstract
The effect of water deficit on shoot growth and fruit development in jojoba was studied in 8-year-old jojoba [Simmondsia chinensis (Link) Schneider] plants. In both fruiting and defruited nonirrigated plants, shoot growth, which started at the beginning of April, stopped in June when the xylem water potential (ψx) measured at dawn fell to a value below the osmotic pressure at the point of turgor loss. Osmotic adjustment during the summer enabled some resumption of growth in the autumn at low ψx values. Irrigated plants grew throughout the warm season only if defruited: competition for assimilates evidently inhibits growth during the period of fruit filling. Fruit growth was not affected by water deficit, since fruit are apparently highly resistant to water loss.
Early Flowering in Lettuce as Influenced by a Second Flowering Time Gene and Seasonal Variation
Authors: Ryder Edward J. 
Published: August 2022

Abstract
Variation in flowering times within genotype classes of the Early Flowering (Efef) gene in lettuce (Lactuca sativa L.) suggested that more than one gene may govern flowering time. Segregation from crosses between earlier and later plants in the early class indicated a second discrete flowering time gene. This gene was confirmed in F3 family analyses and in subsequent progeny comparisons. The first gene is renamed Early flowering-1 (Ef-lef-1) and the second is named Early flowering-2 (Ef-2ef-2). The consequences of the presence of the second gene in cultivars and in the backcross breeding procedure are discussed. Flowering time is influenced by daylength and temperature.
Effectiveness of NAA and Paclobutrazol for Control of Regrowth of Trunk Suckers on ‘Okanagan Riesling’ Grapevines
Authors: Reynolds Andrew G. 
Published: August 2022

Abstract
Three levels of NAA (0, 10,000, and 20,000 ppm) and paclobutrazol (PP333; 0, 250, 500 ppm) were applied in latex paint to suckered vine trunks of ‘Okanagan Riesling’ (Vitis spp.). NAA reduced suckers/vine and percentage of sucker regrowth in each of three seasons. Cluster weight, berries/cluster, and berry weight were increased with NAA in each season, whereas vine size, °Brix, and total acidity (TA) showed a similar trend 1 year following application and thereafter. PP333 reduced sucker number and regrowth, but not as effectively as NAA, and its effects were shorter-lived. No yield components were influenced by PP333 except berry weight, which varied linearly in 1984 and 1986 and quadratically with concentration in 1985. PP333 increased °Brix and TA linearly 1 year following application. Both chemicals tended to reduce pH in 1984 and 1985, but NAA increased pH in 1986 relative to concentration. Chemical names used: 1-naphthaleneacetic acid (NAA); β-1[(4-chorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).
Improving Grapevine Budbreak and Yields by Evaporative Cooling
Authors: Nir G. , Klein I. , Lavee S. , Spieler G. , Barak U. 
Published: August 2022

Abstract
The effect of evaporative cooling on budbreak and yield of Vitis vinifera L. (‘Perlette’ and ‘Thompson Seedless’) vines grown in the southern Jordan Valley in Israel was investigated. Overhead microsprinklers were operated from 0600 to 1800 hr daily during the autumn and winter months, either alone or in combination with cyanamide sprays after pruning. Evaporative cooling decreased the temperature of buds exposed to direct sunlight from 30° to 16°C and that of shaded buds from 25° to 13°. Evaporative cooling induced an early uniform budbreak. However, when evaporative cooling was combined with cyanamide spray, its effect was evident only during the initial phase of bud emergence. In 1985 cyanamide spray and evaporative cooling alone increased yield of ‘Perlette’ by 6% and 6% to 24%, respectively, and by 17% to 46% when both treatments were combined. In 1986 prolonged evaporative cooling increased the yield of ‘Perlette’ by 25% but, in combination with cyanamide, by only 11.6% over the unwetted cyanamide-treated control. In both years, evaporative cooling with or without cyanamide advanced fruit maturation.
Variability of Rubber and Plant Growth Characteristics Among Single-plant Selections from a Diverse Guayule Breeding Population
Authors: Thompson Anson E. , Ray Dennis T. , Livingston Margaret , Dierig David A. 
Published: August 2022

Abstract
Single plant selections from a diverse guayule (Parthenium argentatum Gray) breeding population were evaluated for rubber and resin concentration, rubber and resin yield, and 12 growth characteristics. Thirty-seven superior selections (≈9% of the total of 421 single plant selections) exhibit combinations of satisfactory biomass production, high rubber yield, and strong regeneration and survival after harvesting by clipping the branches at a height of 0.10 m. Rubber concentration (%) was not highly correlated with the 12 plant characteristics measured. In contrast, rubber yield (g/plant) was highly correlated with plant dry weight and other plant characters related to biomass production. Twelve of the 37 superior selections had yields >125 g of rubber per plant, and the rubber concentration of seven of these 12 plants exceeded the mean (7.1%) of the 37 superior selections. Selection for high rubber concentration and yield with strong top regrowth after clipping appears to be feasible, and should expedite the development of a multiple harvesting system and rapid commercialization of guayule as a new domestic source of natural rubber.
Adventitious Root Initiation in De-bladed Petioles from the Juvenile and Mature Phases of English Ivy
Authors: Geneve Robert L. , Hackett Wesley P. , Swanson Bert T. 
Published: August 2022

Abstract
An in vitro system has been developed to study adventitious root initiation in the juvenile and mature phases of English ivy (Hedera helix L.). The system uses de-bladed petiole explants cultured in a defined liquid medium. Adventitious roots are visible macroscopically after 18 days. Juvenile petiole explants show a dose-response to auxin application with optimal root initiation at 100 μM NAA or IAA. With optimal auxin concentration, root initials form in juvenile petiole explants directly from cortical parenchyma cells, which involves induction (1–6 days), meristem organization (6–9 days), and root elongation stages (9–18 days). Sucrose is required for outgrowth of root primordia but not for initiation of primordia. Mature petiole explants respond to auxin with random cell divisions in cortical parenchyma cells; root initials form at a low frequency from callus resulting from this cortical cell division. Distribution of 14C at various times after administration of 14C-labeled NAA is similar in juvenile and mature petioles. Because of their difference in rooting potential, coupled with similarity in anatomical organization, distribution of 14C from NAA, and identical genotype, juvenile and mature petioles provide an excellent experimental system for analyzing the morphogenetic, physiological, and genetic basis of rooting potential. Chemical names used: 1-napthaleneacetic acid (NAA); 1H-indoIe-3-acetic acid (IAA).
Evaluation of DRIS for Judging the Nutritional Status of Hazelnuts
Authors: Alkoshab Othman , Righetti Timothy L. , Dixon A.R. 
Published: August 2022

Abstract
The Diagnosis and Recommendation Integrated System (DRIS), which uses nutrient element concentration ratios as indicators of nutrient deficiency, was used to evaluate current sufficiency ranges for hazelnut trees. Reference values that were derived from published and unpublished field data were used to calculate DRIS indices for N, P, K, Ca, Mg, Mn, Fe, Cu, B, and Zn. A nutritional imbalance index (NII) was computed as the sum of DRIS indices irrespective of sign, and a threshold NII value (mean NII + 1 SD), above which severe imbalances are expected, was established. DRIS diagnoses were then compared with the sufficiency range approach to determine if relative deficiencies or excesses associated with severely imbalanced trees would have been routinely detected in 624 mineral analyses of hazelnut leaves. A previously published field trial was also reevaluated. DRIS diagnosis generally agreed with the diagnoses made by the sufficiency range method, especially if sufficiency ranges for some elements were made more narrow. However, some nutrients were never identified by DRIS as a major relative deficiency or excess in any of the trees judged severely imbalanced, based on the sum of DRIS indices. Nitrogen and Mg deficiencies were not detected unless lower NII thresholds were used. Unfortunately, lowering NII thresholds enough to detect N and Mg deficiencies identified some high-yielding trees as severely imbalanced. DRIS will not detect all deficiencies or excesses. Therefore, DRIS is best viewed as a supplement to sufficiency range diagnoses that provides additional information when severe imbalances are detected.
Nitrate Monitoring for Pumpkin Production on Dryland and Irrigated Soils
Authors: Swiader John M. , Sullivan Joseph G. , Grunau John A. , Freiji Fadi 
Published: August 2022

Abstract
Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO3-N in dryland-grown and irrigated pumpkins (Cucurbita moschata Poir.). The level of NO3-N in petioles of recently mature leaves was a good indicator of the seasonal N status for pumpkins on irrigated sand, and to a lesser degree for pumpkins on dryland loam. Petiole NO3-N concentrations decreased with time and with decreasing N rate at both sites, with the rate and extent of decrease considerably greater on the irrigated sand. The optimum time of sampling was at about initial fruit set or early fruiting. Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO3-N at early fruiting were estimated at 6300 and 8000 μg·g−1, respectively, in dryland and 4000 and 6700 μg·g−1, respectively, for irrigated plantings. Deficiency symptoms were associated with NO3-N concentrations <1500 μg·g−1. Soil NO3-N levels proved unsatisfactory as a NO3-N index in dryland soil, but meaningful relationships (R2 = 0.31) were obtained between fruit yield and soil NO3-N on irrigated sand. Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively. However, N fertilizer rates of 202 and 269 kg N/ha delayed harvest 9 days on irrigated sand and 15 days on dryland loam, compared to lower N rates.
Influence of Orientation and Position of Fruiting Laterals on Canopy Light Penetration, Yield, and Fruit Quality of ‘Granny Smith’ Apple
Authors: Tustin D. Stuart , Hirst Peter M. , Warrington Ian J. 
Published: August 2022

Abstract
Fruiting laterals were tagged within the inner and outer canopy zones of the basal, mid, and upper tiers of dormant, mature central-leader ‘Granny Smith’ apple (Malus domestica Borkh.) trees and were classified into pendant (>120°), horizontal (30°-120°), and vertical (0°-30°) types. Transmission of photosynthetic photon flux (PPF) to spur sites on tagged laterals was measured in mid-season and fruits from these sites were harvested at commercial maturity for assessment of fresh weight, soluble solids concentration (SSC), starch pattern index, and background color. Pendant laterals produced fewer, smaller, and greener fruit per flowering spur than horizontal or vertical laterals. Fruit fresh weight and soluble solids concentration increased with increasing height in the canopy and were higher in the outer compared with the inner horizontal canopy position. Background color followed a trend opposite to that of fresh weight and soluble solids concentration, with fruit from the lower inner canopy regions being greenest. Both fresh weight and SSC showed highly positive correlations with the percentage transmission of PPF. Fruit set showed a positive correlation with PPF, although the relationship was weaker than that for fresh weight or SSC. PPF penetration was lower to pendant laterals than to horizontal and vertical laterals and declined from upper to lower and from outer to inner canopy positions. Pendant fruiting laterals received < 15% of PPF, irrespective of location within the canopy.
Influence of Pruning and Urea Sprays on Growth and Fruiting of Spur-bound ‘Delicious’ Apple Trees
Authors: Ferree David C. , Forshey C.G. 
Published: August 2022

Abstract
Spur quality and leaf nutritional levels were determined in various canopy sections of mature spur-bound ‘Delicious’-type apple (Malus domestica Borkh.) trees and then various pruning and foliar urea treatments were applied to alter growth and improve fruit size. Fruit size declined from the top to the bottom of the canopy of mature spur-bound ‘Starkrimson Delicious’ trees with a similar pattern in the following criteria: leaf area/spur, spur specific leaf weight, and spur bud diameter. Spur leaf area was higher in the top center and east sections than in the top south. Spur bud diameter in the bottom third of the canopy was highest in the north and east sections, lowest in the central section, and intermediate in the south and west sections. Concentrations of leaf Mn, Zn, B, Al, and Na tended to increase from the top to the bottom of the canopy. Four urea sprays (6 g urea/liter) during the cell division period of fruit growth had little influence on spur quality, but fruit weight was increased 3 successive years. Spur pruning of 25-year-old ‘Starkrimson Delicious’ trees was not sufficient to increase shoot growth or improve spur quality, but heading back into 2-year-old wood plus spur pruning increased shoot number by 38%. Spur and heading-back pruning increased the number of shoots and total shoot leaf area of 13-year-old ‘Red Chief Delicious’ trees, and the combination of both pruning types led to the greatest increase. Heading-back of the younger trees increased leaf area of both shoots and spurs and spur pruning also increased leaf area/spur. Heading-back pruning increased average fruit weight, and the increase was positively correlated with total leaf area, shoot leaf area, and number of shoot leaves/mm of branch circumference.
Responses of Parthenocarpic Cucumbers to Low-oxygen Storage
Authors: Kanellis Angelos K. , Morris Leonard L. , Saltveit Mikal E. 
Published: August 2022

Abstract
Parthenocarpic cucumber fruit (Cucumis sativus L. cv. Deliva) of marketable maturity (10 to 14 days after anthesis) were held at 12.5° or 20°C in reduced O2 levels for 5 or 18 days before transfer to air. Carbon dioxide production at reduced O2 levels was generally less than in air; however, at O2 levels < 0.5%, anaerobic respiration resulted in increased rates of CO2 production. Upon transfer to air after 18 days, all samples from reduced O2 showed increased CO2 production rates that equalled or exceeded that of the air controls. Except at 0.0% and 0.25% O2 levels, ethylene production was increased in reduced O2. After transfer to air, ethylene production increased and the increase was inversely related to the previous O2 level. Ethanol and acetaldehyde production were measureable for fruit held in 1% O2 after 18 days at 12.5° and showed dramatic increases at lower O2 levels. Low-O2 injury (pitting) developed on most fruit held at 0.0% O2 and on many fruit held at 0.25% O2. Only minima! commercial benefits are likely to be realized from storage of 1 to 3 weeks in 0.5% to 2.0% O2 at 12.5°.
Postharvest Characteristics of Geraldton Wax Flowers
Authors: Joyce Daryl C. 
Published: August 2022

Abstract
Abscission of flowers of Geraldton wax (Chamelaucium uncinatum Schau., Myrtaceae) exposed to ethylene was prevented by pulsing with silver thiosulfate. Both a short pulse (15 min, 4.0 mm Ag+) at 25°C and an overnight pulse (0.5 mm Ag+) at 2° were effective treatments. Silver thiosulfate did not improve the vase-life of flowers held in air. Gamma irradiation (60Co source), an insect control measure, resulted in a reduction in vase-life; even at doses as low as 0.05 kGy. Vase-life of Geraldton wax flowers was not affected by prior storage for up to 2 weeks at 0° to 2°. Iprodione pretreatment (1 g·liter−1, 30-sec dip) for Botrytis cinerea Pers. control improved the vase-life of flowers stored for 2 weeks. A preservative solution containing sucrose (1% to 3% w/v) and 8-hydroxyquinoline sulfate (200 mg·liter−1) increased the vase-life of Geraldton wax flowers. Higher sucrose levels (>5% w/v) may cause desiccation of foliage and excessive nectar secretion from floral nectaries. Chemical name used: 3-(3,5-dichlorophenyl)-N-(1-methylethyl)-2,4-dioxo-1-imidazolidinecarboxamide (iprodione).
Sixteen-year Performance of Five Nucellar and Old-budline ‘Valencia’ Oranges
Authors: Rouse Robert E. , Maxwell Norman P. 
Published: August 2022

Abstract
Sixteen-year mean and cumulative yields are reported for nucellar sweet orange [Citrus sinensis (L.) Osbeck] ‘Olinda Valencia’, ‘Campbell Valencia’, ‘Cutter Valencia’, ‘Frost Valencia’; one Texas Agricultural Experiment Station (TAES) nucellar ‘Valencia’ selection, and old-budline ‘Valencia’ on sour orange (C. aurantium L.) rootstock. Yields for individual years were consistent among the highest with ‘Olinda Valencia’ and ‘Campbell Valencia’, and lowest with ‘Frost Valencia’ and old-budline. Cumulative yields were comparable for ‘Olinda Valencia’ and ‘Campbell Valencia’. Tree canopy volumes were greatest for the TAES nucellar selection and smallest for old-budline, which was not significantly different than ‘Frost Valencia’ or ‘Olinda Valencia’. Based on yield per unit of canopy, ‘Olinda Valencia’ had the highest yield efficiency and lowest coefficient of variation among years. Internal fruit quality data (°Brix, acid, °Brix : acid ratio, and percentage juice) did not differ among cultivars.
Is the P Gene in Common Bean Located in Linkage Group VII?
Authors: Bassett Mark J. , Awuma Kafui 
Published: August 2022

Abstract
Linkage tests in common bean (Phaseolus vulgaris L.) were made between black-seeded lines carrying the marker genes round leaf (rnd) and stipelless lanceolate leaf (sl) and the white-seeded lines ‘Miami’ and ‘Inepuisable’ and an induced mutant for white seed, 3-254. The crosses ‘Miami’ × ‘Inepuisable’ and ‘Miami’ × 3-254 were made to test for allelism of the white seed genes in these lines. ‘Miami’ was found to be allelic to ‘Inepuisable’ and 3-254 at the white seed locus (presumed to be P). Furthermore, there was no indication of linkage between the white seed locus and the markers rnd and sl. These results contradict expectations of linkage of P with rnd and sl based on previously published linkage maps and indicate that the present map position of P is incorrect.
Effects of External Ethylene on the Production of Endogenous Ethylene in Olive Leaf Tissue
Authors: Goren Raphael , Nishijima Chic , Martin George C. 
Published: August 2022

Abstract
Olive (Olea europaea L.) leaves are characterized by their ability to respond to exogenous ethylene by a 100- to 400-fold enhanced ethylene production irrespective of leaf age or time of year when sampled. The autoenhancement of ethylene production from intact or detached leaves is positively correlated with the concentration of external ethylene. A lag time of 72 to 120 hr occurred before the autoenhancement of ethylene production could be observed. An autoinhibition of ethylene production was usually observed during the first 24 to 48 hr. The effect was, however, much less pronounced. This autoinhibition of ethylene production apparently does not involve wound ethylene. Olive fruit normally produce only negligible amounts of ethylene, and the enhanced ethylene evolution, which was observed after the fruits were exposed to exogenous ethylene, was found to be exogenous ethylene that was trapped by the fruit tissue during its exposure to ethylene. In leaves, however, autoenhancement of ethylene production evidently is a physiological response that may induce a senescing process in the leaves rather than abscission.