bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physiological and Growth Responses of Mature Peach Trees to Postharvest Water Stress
Authors: Larson K.D. , DeJong T.M. , Johnson R.S. 
Published: August 2022

Abstract
Peach trees (Prunus persica L. Batsch cv. Regina) were subjected to three levels of postharvest irrigation between 15 June and 15 Oct. 1983. Wet-treatment (control) trees were irrigated at 3-week intervals, medium-treatment trees received one, and dry-treatment trees received no postharvest irrigations. Significant differences in seasonal patterns of stomatal conductance were found among all treatments, with conductance varying in proportion to irrigation level. Wet-treatment pre-dawn water potential (ψw) remained nearly constant at −0.3 MPa throughout the postharvest season, whereas the dry-treatment readings became more negative as the season progressed. Differences in mid-day ψw were less distinct, but generally reflected pre-dawn water status. The seasonal increase in trunk radius of the dry-treatment trees was reduced by 33% relative to either wet or medium treatments. The amount of daily trunk radial shrinkage was inversely proportional to irrigation level. Dormant pruning weights were 13% less in dry treatments than wet treatments. Return bloom of dry-treatment trees in Spring 1984 was 30% and 40% greater than medium- and wet-treatment return bloom, respectively. Dry-treatment fruit set was 70% greater than medium- or wet-treatment fruit set. Following fruit thinning, there were no significant differences among treatments for fruit yield or fruit size, but fruit maturity was slightly delayed in the dry treatment.
Seasonal Plant Shading, Growth, and Fruiting in ‘Earliglow’ Strawberry
Authors: Ferree David C. , Stang Elden J. 
Published: August 2022

Abstract
‘Earliglow’ strawberry (Fragaria × ananassa Duch.) plants were covered with 60% shade cloth in Wisconsin and Ohio during each of the following developmental phases: 1) check, no shade; 2) the runnering period after plant establishment; 3) flower initiation period in Fall 1983; 4) early growing season (from mulch-off until first flowering); 5) the fruiting period, 1984; and 6) constant shade. ‘Earliglow’ has a photosynthetic light response curve typical of a C, plant. Leaf dry weight per plant was decreased at both locations by constant shading during the fruiting period, just prior to plant sampling. Crown dry weight was reduced by constant shading. Leaf nutrient element contents of K, Ca, Mg, B, and Fe varied by location, but were not appreciably affected by shading treatments. Shading during the active runnering period resulted in increased total yield the following spring by 12% in Wisconsin and 17% in Ohio. In Wisconsin, increased total yield was the result of increased number of fruit in midseason harvests. Berry size was increased for constant shading or shading during fruiting, but yield was offset by lower fruit numbers. Usable fruit in Ohio on plants shaded during runnering was increased by 20% compared to the unshaded control. Constant shade resulted in an 18% and 46% reduction in total yield in Wisconsin and Ohio, respectively. Shading during the fruiting period resulted in yield reductions in both Ohio (13%) and Wisconsin (27%). Yield reductions were also noted in Ohio when shading occurred during early spring (21%), just prior to fruiting, or during flower formation (24%) the previous fall. Shading during the spring growth and fruiting period delayed fruit maturity and peak harvest 5 to 7 days.
Zinc Complexation in the Phloem of Blight-affected Citrus
Authors: Taylor K.C. , Albrigo L.G. , Chase C.D. 
Published: August 2022

Abstract
Extracts from Zn-accumulating phloem tissue of blight-affected trees had higher Zn-binding capacity than extracts from healthy trees. A 4-kDa, highly anionic, zinc-binding fraction was isolated from the phloem of predecline and decline stage ‘Valencia’ sweet orange [Citrus sinensis (L.) Osbeck] and ‘Marsh’ grapefruit (C. paradisi Macf.) trees grown on blight-susceptible rootstocks. Diethylaminoethyl (DEAE) Sephadex chromatography revealed the Zn-binding fraction contained at least four different anionic species. Two of the four species were present in healthy as well as predecline- and decline-stage trees. The other two species were found in only the predecline and decline trees. All Zn-binding factors were similar to the poly(γ-glutamyl-cysteinyl) glycine peptides in terms of size, anionic character, pH and temperature stability, capacity to bind other metals, and spectrophotometric properties.
Fecundity of Crosses Between Tetraploid and Hexaploid Vaccinium
Authors: Lyrene P.M. 
Published: August 2022

Abstract
The purpose of this study was to compare the relative fecundity of tetraploid × hexaploid and hexaploid × tetraploid crosses in blueberry. Four types of crosses were made using cultivars and advanced breeding lines consisting largely of V. ashei Reade (6×) and V. corymbosum L. (4×). Fruit set, number of developed seeds per ripe berry, and number of seedlings per pollinated flower were determined. Tetraploid × hexaploid crosses averaged as high in percent fruit set as tetraploid × tetraploid crosses, but seed number per ripe fruit was only 29% as high and seedling number per pollinated flower only 35% as high. Hexaploid × tetraploid crosses, by contrast, set only 48% as much fruit as hexaploid × hexaploid crosses. Despite reduced fruit set, hexaploid × tetraploid crosses averaged almost as high in number of seedlings produced per pollinated flower as the reciprocal cross. In both types of cross, the success rate strongly depended on the particular genotypes used in crossing. The overall success rate from crosses between tetraploid and hexaploid clones was 2.32 seedlings per pollinated flower, which is high enough to allow production of large pentaploid populations for use in breeding.
Anthocyanin, Aglycone, and Aglycone–sugar Content in the Fruits of Temperate North American Species of Four Sections in Vaccinium
Authors: Ballington James R. , Kirkman William B. , Ballinger Walter E. , Maness Eleanor P. 
Published: August 2022

Abstract
HPLC analysis of the fruits of species of Vaccinium sections Herpothamnus (V. crassifolium and V. sempervirens), Pyxothamnus (V. ovatum), Polycodium (V. stamineum), and Oxycoccoides (V. erythrocarpum), determined that species in these sections fall into two distinct groups. Species in Herpothamnus and Pyxothamnus contained the 3-monoarabinosides, 3-monogalactosides, and 3-monoglucosides of cyanidin, dephinidin, malvidin, peonidin, and petunidin. Differences in anthocyanins (ACY), aglycones, and aglycone-sugars were not useful in distinguishing among species in Herpothamnus. However, differences in aglycones and aglycone-sugars were useful in distinguishing between Herpothamnus and Pyxothamnus. Species in Polycodium and Oxycoccoides contained more than 90% cyanidins, no delphinidins, and small percentages of peonidins and malvidins. Vaccinium stamineum also contained no petunidins. These two sections were similar in ACY and aglycones, but did vary in percent galactose and arabinose. Potential crossabilities, along with overall similarities in ACY among these and other sections, support a fairly recent origin of North American sections of the genus Vaccinium.
Carbon Metabolism in Scions of Colorado Blue Spruce: I. Needle Starch
Authors: Beeson Richard C. , Proebsting William M. 
Published: August 2022

Abstract
Needle starch metabolism was studied during graft development of Colorado blue spruce (Picea pungens Englemann ‘Hoopsi’) scions on Norway spruce [Picea abies (L.) Karst] rootstocks. Starch accumulated during the initial stages of union formation, but the rate of accumulation slowed over time. Peak starch content in developing greenhouse grafts was ≈30% and, in lath house grafts, ≈50% of that in 3-year-old grafts forced in the greenhouse. Prior to budbreak, starch content declined rapidly, stabilizing at pre-grafting levels during shoot elongation. Grafts with misaligned unions accumulated starch during the first week, but the starch content then declined. Preventing photosynthesis in scions during union formation prevented starch accumulation, but did not affect graft success or subsequent scion growth. We concluded that neither starch accumulation nor current photosynthesis in the scion were required during union development.
Carbon Metabolism in Scions of Colorado Blue Spruce: II. Carbon Storage Compounds
Authors: Beeson Richard C. , Proebsting William M. 
Published: August 2022

Abstract
The study evaluated the roles of storage carbohydrates and neutral lipids in the success of Colorado blue spruce (Picea pungens Englemann ‘Hoopsi’) grafts. These scions do not require photosynthesis nor receive photosynthates from the rootstock during union development. Carbohydrate and neutral lipid contents, along with respiration and scion water relations, were measured during union development. Stored carbon compounds were sufficient to supply the needs of the scion during the 9 weeks of union development. Estimates of carbohydrate use indicated that decreases in sugar content (bark and needle) were insufficient to account for more than 25% of the estimated respiration. The results indicate that the quantity of carbon storage compounds is not a factor in graft success. We propose that neutral lipids may be the major carbon reserve of the scion during graft formation.
Plant Population Influences Growth and Yields of Bell Pepper
Authors: Stoffella Peter J. , Bryan Herbert H. 
Published: August 2022

Abstract
Bell peppers (Capsicum annuum L. cv. Early Calwonder) were plug-mix seeded at 13-, 25-, 38-, and 51-cm within-row spacings in two rows on raised beds and thinned to one, two, or three plants per hill upon emergence. The experiments were conducted on commercial pepper fields located in southern Florida during the Winter 1983 and Spring 1984 seasons. Populations ranged from 21,527 to 258,328 plants/ha. Plant growth characteristics were measured at anthesis and just before the final harvest in each experiment. Root and shoot weights, shoot : root ratios, and stem diameters generally decreased and plant heights generally increased in response to higher plant populations. The lower shoot : root ratios at higher plant populations indicated that plants were producing more root mass in proportion to shoot mass than plants at lower populations. Number of primary and secondary branches per plant in the two experiments averaged 2.7 and 5.3, respectively, and were generally not influenced by plant populations. Marketable fruit yields/ha increased linearly in response to higher plant populations. Marketable fruit number and weight per plant decreased with higher plant populations, whereas fruit size (g/fruit) was unaffected. This observation suggested that the higher marketable yields/ha at higher plant populations were attributed to more plants with a lower number of similarly sized fruits per plant. The 25-cm within-row spacing with two plants per hill resulted in 81,109 plants/ha, the optimum marketable pepper fruit yield.
Electrophoretic Characterization of Diploid Plums of the Southeastern United States
Authors: Byrne David H. , Littleton Thomas G. 
Published: August 2022

Abstract
Twenty-nine Japanese-type plum clones were assayed for isozymic variability for eight enzyme systems. Glutamate dehydrogenase (GDH), leucine amino-peptidase (LAP), malate dehydrogenase (MDH), phosphoglucose isomerase (PGI), phosphoglucomutase (PGM), and peroxidase (PX) showed variability among the plums surveyed. 6-phosphogluconate dehydrogenase (6PGD) and triosephosphate isomerase (TPI) were not variable. Isozymic characterization uniquely identified 38% of the clones. The remainder separated into groups of two to three clones that were distinguishable using vegetative morphological characteristics. Reported parentage of five out of nine plums examined was not consistent with their isozymic genotypes.
Growth and Fruiting of ‘Delicious’ Apple Trees as Affected by Severity and Season of Pruning
Authors: Barden John A. , DelValle Terry B. G. , Myers Stephen C. 
Published: August 2022

Abstract
Individual scaffold limbs on 5-year-old ‘Red Prince Delicious’ apple (Malus domestica Borkh.) trees on five rootstocks were unpruned or pruned in Aug. 1981 or Feb. 1982 using three severities at each time. Responses to summer and dormant pruning were similar; no significant interactions occurred. In Dec. 1982, branch circumference was inversely related to pruning severity. Compared to the control, all pruning severities decreased shoot number and increased mean shoot length in 1982; only the most severe pruning suppressed total shoot growth. Flowering and fruiting in 1983 were inversely related to pruning severity.
Mulch Surface Color Affects Yield of Fresh-market Tomatoes
Authors: Decoteau Dennis R. , Kasperbauer Michael J. , Hunt Patrick G. 
Published: August 2022

Abstract
The influence of polyethylene mulch surface color on the plant light environment and tomato (Lycopersicon esculentum Mill) production was investigated. White- or silver-painted mulches reflected more total light, and a lower ratio of far-red relative to red light, than mulches painted black or red. Soil temperatures were warmer under the black and red mulches. Mulch color also affected the yield and growth of tomato. Tomato plants grown with red mulch generally had the greatest early marketable yields and produced the least amount of foliage. Plants grown with a white or silver-colored mulch had lower early marketable yields but produced more foliage. These results suggest that mulch surface color can induce changes in the plant microclimate (e.g., spectral balance and quantity of light, root zone temperatures) that can act through natural regulatory systems within the growing plant and affect tomato plant growth and fruit production.
Water Deficits and Rooting Volume Modify Peach Tree Growth and Water Relations
Authors: Proebsting L. , Jerie P. H. , Irvine J. 
Published: August 2022

Abstract
To compare the effects of water deficits and restricted root volume, 1- and 2-year-old peach trees (Prunus persica L.) with roots divided among four 2.5-Iiter pots were irrigated daily with 30% (deficit irrigation) or 100% (non-deficit) replacement of water used the day before. The water was applied to one, two, or all four pots during the period of rapid terminal growth. After 7 weeks, all trees received 100% replacement of water used the previous day. After terminal growth ended, the root : shoot ratio of the 2-year-old trees was adjusted by 1) tripling available soil volume, 2) removing two-thirds of lateral branches, 3) both 1 and 2, 4) treatment 3 defoliated, or 5) left unchanged. Deficit irrigation reduced midday leaf water potential, leaf conductance, and terminal growth equally, regardless of irrigated soil volume, whereas in non-deficit irrigated trees these factors were proportional to the irrigated soil volume. After deficit irrigation ended, terminal growth resumed at rates above those of the trees with non-deficit irrigation applied to all four pots and proportional to the severity of growth reduction during deficit irrigation. Pruning and defoliation increased leaf conductance within 3 days. Increased soil volume increased leaf conductance after 4 weeks. Deficit irrigation nearly eliminated flowering for the following year. Tripling the soil volume overcame the effect of deficit irrigation on flowering, but pruning did not. Defoliation inhibited flowering. The effect of restricted irrigated soil volume was similar to that of deficit irrigation. Increasing root : shoot ratios by adjusting the soil volume or by pruning the shoot always increased leaf conductance.
Nitrogen Level and Time of Mechanized Summer Shearing Influence Long-term Performance of a High-density ‘Redskin’ Peach Orchard
Authors: Walsh Christopher S. , Allnutt Francis J. , Miller Anita N. , Thompson Arthur H. 
Published: August 2022

Abstract
‘Redskin’ peach (Prunus persica Batsch.) trees, planted at a high-density spacing (3 × 5 m), were fertilized annually with urea at rates of 45, 90, or 135 kg·ha−1. Trees were trained to a trapezoidal hedge by annual, mechanized, summer pruning. Within each fertilizer plot, subplots of five summer-pruning treatments were applied. Single pruning treatments were made at 120 days after full bloom (DAFB) and 150 DAFB. Paired pruning treatments were applied 30 + 60 DAFB, 60 + 120 DAFB, and 60 + 150 DAFB. Pruning at 120 DAFB alone, and in combination with pruning at 60 DAFB, decreased trunk cross-sectional area (TCA), fruit soluble solids content, and weight, while increasing the percentage of surface that was red. Pruning at 30 DAFB followed by a second pruning at 60 DAFB decreased leaf Ca concentration in comparison to pruning treatments applied later in the season. Increasing N fertilization also decreased leaf Ca. Year, N level, and pruning treatments gave a statistical interaction on mean fruit weight and yield.
Nitrogen Concentration and Photosynthetic Photon Flux in Greenhouse Tomato Production: I. Growth and Development
Authors: Larouche Régis , Gosselin André , Vézina Louis-Philippe 
Published: August 2022

Abstract
Tomato plants (Lycopersicon esculentum Mill. cv. Vedettos) were grown in growth chambers under two photosynthetic photon flux (PPF; 125 and 250 μmol·s−1·m−2, high-pressure sodium lamps) conditions for 18 hr and four N fertilization regimes (5, 10, 15, and 20 meq·liter−1) to characterize the ratio of vegetative to reproductive growth. At the lower PPF, vegetative growth was limited and did not respond to N increments in the nutrient solution. At 125 μmol·s−1·m−2, maximum yields were obtained at the lowest N fertilization level. At 250 μmol·s−1·m−2, maximum leaf dry weight and yields were obtained at intermediate N fertilization levels (10 and 15 meq·liter−1). Light levels did not alter the nitrate content of stem sap (but high PPF resulted in nitrate accumulation in leaves) but, at low PPF, nitrate accumulated in leaves at 20 meq N/liter. Nitrate in stem sap varied only slightly with N increments in the nutrient solution. The ratio of fruit fresh weight to leaf fresh weight decreased as N increased in the nutrient solution.
Soil pH and Extractable Elements under Blight-affected and Healthy Citrus Trees on Six Florida Soils
Authors: Wutscher Heinz K. 
Published: August 2022

Abstract
Citrus trees affected with blight, a disease of unknown cause, were associated with soils having higher pH and Ca levels than soils under healthy trees. A detailed study of soil samples taken in 5-cm increments to a depth of 45 cm under healthy and blight-affected trees from five sites showed that pH, determined separately for each increment, showed significantly lower mean pH values under healthy trees. Double-acid (0.05 N HCI and 0.025 N H2SO4) extracts of soil under blighted trees contained more Ca at all five sites. Higher P and K were associated with blight in three of six and four of six comparisons, respectively. In one of five sites, Mn and Zn were higher and Fe lower under blighted trees. The soil under trees in very early stages of blight in the heavily affected part of a block compared with soil under trees in the healthy part of the block was higher in pH and Ca. Soil where lime was incorporated deeply by mixing or deposition of dredged calcareous subsoil on the surface was associated with the most severe incidence of blight.
Pecan Nut and Kernel Characteristics Show Genotype–Environment Interactions
Authors: Thompson T. E. , Young E. F. , McIlrath W. O. , Petersen H. D. , Sibbett G. S. 
Published: August 2022

Abstract
Results are presented for performance of pecan [Carya illinoinensis (Wangenh.) C. Koch] clones at six established National Pecan Advanced Clone Testing System (NPACTS) sites for 16 nut quality factors from 1980 through 1985. Total nut weight and percent kernel were significantly greater at Tulare, Calif. than at any other location, with ≈80% of the clones averaging 6.5 g/nut or more and ≈90% averaging at least 54.5% kernel. Nut weight was smallest at El Paso, Texas. Daily mean temperatures during nut expansion may be a major factor determining nut weight response. Low nut density was characteristic of more clones at Baton Rouge, La. than at any other location. Kernel color was lightest at El Paso and darkest at Baton Rouge, with darker color appearing to be related to high field moisture conditions before harvest. Nut weight was not related to kernel percentage, color, or percent kernel covered with fuzz (packing material); thus, large nuts are not necessarily of lower quality and can be selected in an effective breeding program. Amount of nut “packing material” retained in the sutures of kernel halves after shelling was generally not related to other traits, except that material retained in ventral grooves increased with nut and kernel weight. Depth and width of dorsal grooves were not related to retention of packing material and can be disregarded in future pecan nut evaluation systems. Many other expected character relationships were verified and the overall NPACTS nut evaluation system will be revised based on these results.
Plant Analysis for Nitrogen Fertilization of Asparagus
Authors: Gardner B. R. , Roth R. L. 
Published: August 2022

Abstract
This study was initiated to establish critical N plant tissue levels for asparagus (Asparagus officinalis L.) during the fern growing season. Tissue samples for chemical analysis were taken from asparagus plants over three growing seasons. The experiment consisted of nine treatments with five levels of water ranging from 750 to 4200 mm·ha−1 and five levels of N fertilizer ranging from 100 to 655 kg N/ha. Only the cladophylls were sampled during the fern growing season beginning in mid-April and monthly through mid-September. Total N concentration at various sampling dates and spear yield were highly correlated. Total N concentration indicated the N status of the asparagus plant. Minimum or critical levels of total N were established for the fern growing season in the desert regions of Arizona.
Response of Carrot Seeds to Heat Treatments
Authors: Strandberg J. O. , White J. M. 
Published: August 2022

Abstract
Tolerance of carrot seeds (Daucus carota L.) to heat treatments that could eradicate seedborne pathogens was investigated. Germination and emergence of seedlings from seeds treated in hot water at 35, 40, 45, 50, or 55C from 4 to 20 min were not affected, but seeds treated at 60C for 8 min or more were affected adversely. At 45 and 50C, treatment durations as long as 48 min did not affect emergence, but >20 min at 55C reduced emergence. Similar results were obtained when seeds were treated at the same temperatures in water containing 1.1% sodium hypochlorite (NaOCI). Emergence of seeds treated in hot water or 1.1% NaOCl and planted within 5 days generally was similar to that of treated seeds stored for 90 days at 20C in 60% RH before planting. Any existing differences were small and not clearly related to temperature–duration treatment combinations. Percent emergence from seeds of 19 out of 25 hybrid cultivars treated at 50C for 15 min was reduced by an average of 2.9%, but differences for untreated seeds ranged from −13.3% to +4.8%. Emergence from hot water-treated seeds was reduced after 6 weeks of storage at 70% and 80% RH, but not at 20% to 60% RH. Prolonged treatment and the higher temperatures were particularly effective in reducing populations of seedborne Alternaria dauci.