bluuebunny/crossref_metadata_2025 huggingface dataset:
Anatomy and Morphology of Sun- and Shade-grown Ficus benjamina1
Authors: Fails Barbara S. , Lewis A. J. , Barden J. A.
Published: August 2022

Weeping fig (Ficus benjamina L.) plants were greenhouse-grown under full sun or 75% light exclusion. Shade-grown leaves were larger, thinner, flatter, and darker green than sun-grown leaves. Sun- and shade-grown plants had the same total leaf area and were the same height. Shade-grown leaves had a single, poorly developed palisade layer with large chloroplasts dispersed throughout the palisade cells. Sun-grown leaves had one or two layers of well developed palisade cells with the chloroplasts aligned primarily along the radial walls. Stomatal density was greater in sun-grown leaves, but shade-grown leaves had more stomata per leaf.
Effects of Deletion and Enhancement of Ultraviolet-B (280–315nm) Radiation on Plants Grown at 3000 m Elevation1
Authors: Becwar Michael R. , Moore Frank D. , Burke Michael J.
Published: August 2022

Effects of deletion and enhancement of 280–315 nm ultra-violet (UV-B) radiation on pea (Pisum sativus L.), potato (Solanum tuberosum L.), radish (Raphanus sativus L.), and wheat (Triticum aestivum L.) plants were examined at a 3000 m elevation field site, which provided a 49% increase in midday effective (biologically weighted) UV-B radiation relative to near sea level. Wheat plants grown under Aclar or cellulose acetate film, which transmit UV-B radiation, were shorter than plants grown under Mylar film, which excludes UV-B radiation. Effective UV-B radiation levels at solar noon in the open and under the Aclar and cellulose acetate were 61, 55, and 44 mW m−2, respectively. There were no significant differences in potato, radish, and wheat dry weights attributable to UV-B radiation among the above treatments. The dry weights of all 4 species and pea and wheat plant height were not significantly decreased by a supplemental enhancement of 32 mW m−2 effective UV-B radiation from cellulose acetate filtered FS-40 sunlamps for 6 hours each day, relative to control plants that received only solar UV-B radiation. The results suggest that wheat plant height is more sensitive to deletion of UV-B radiation than the other parameters measured, and that the 4 species studied can tolerate the level of enhanced UV-B radiation used with concomitant high levels of visible radiation with no significant reduction in dry weight accumulation.
Recovery of Tomato Ringspot Virus from Inoculated Apple Trees1
Authors: Cummins James N. , Gonsalves Dennis
Published: August 2022

Tomato ringspot virus (TmRSV) was detected by ELISA indexing in leaf tissue from 23 of 59 clones of Malus domestica Borkh., 1 to 6 years after inoculation with TmRSV-infected buds. However, TmRSV was repeatedly detected from only 10 of the 23 clones: Mailing (M) 26, MM 106, MAC-30, MAC-39, and P-2 and the fruiting cultivars ‘Northern Spy’, ‘Spigold’, ‘Spijon’, ‘Stayman’, and ‘Wayne’. ‘Northern Spy’ and most of its derivatives appeared to be highly susceptible to TmRSV infection, in that the virus was consistently recovered from inoculated plants.
Cuticular Retention in Vitro and Localization of Zn after a Foliar Application of Zinc-containing Fungicides1
Authors: Chamel A. R. , Marcelle R. D. , Eloy J. F.
Published: August 2022

The cuticular retention of zinc contained in 4 fungicides (Antracol, Calyram, M-Special, and Polyram Combi) and zinc chloride was studied using isolated pear leaf cuticles (Pyrus communis L. cv. Passe Crassane). The retention of Zn by the cuticular discs was significant after a 24-hour immersion in each fungicide (0.2% w/v). The distribution coefficient, calculated as the ratio of the zinc retained by the cuticles (in μg/g) to the zinc content of the immersion liquid (in μg/ml), varied from 25.1 to 88.2 for the fungicides, but was only 5.7 in the case of ZnCl2. Laser probe mass spectrography indicated that Zn supplied with the fungicides remained superficially localized 24 hours after a foliar application on maize (Zea mays L. cv. Dekalb 202); Zn was detectable only in the surface zone corresponding to a maximum depth of 30 μm from the adaxial leaf surface.
Relationship of Number of Long Nights to Meristem Development and Flowering in Kalanchoe1
Authors: Nell T. A. , Fischer J. M. , Sheehan T. J. , Barrett J. E.
Published: August 2022

Cultivars of Kalanchoe blossfeldiana Poelln. varied in number of long nights required for complete flower initiation and development. ‘Montezuma’ and ‘Texas Sunset’ requried 14 long nights, while ‘Pixie’, ‘Nugget’, ‘Cactus Candy’, ‘Goddess’, ‘Tobasco’, ‘Osage Orange’, ‘Toltec’, ‘Adobe Rose’ and ‘Rotkappchen’ required 15 to 28 nights. Height of apical meristems increased in ‘Montezuma’ after 7 long nights, but changes were not evident in ‘Pixie’ until 9 long nights. Scanning electron microscopic analysis showed first evidence of sepal primordia in ‘Pixie’ after 28 long nights—6 nights later than ‘Montezuma’. Differences in the number of long nights required for flower induction were related to delayed floral initiation rather than organogenisis or maturation.
Performance of Tomato and Pepper Seeds Germinated before Planting1
Authors: Ghate Suhas R. , Phatak Sharad C.
Published: August 2022

Seeds of tomato (Lycopersicon esculentum Mill.) and pepper (Capsicum annuum L.) were either germinated before planting, primed (immersed in an aerated solution of potassium phosphate and ammonium phosphate for 72 hours (tomato) or 120 hours (pepper) and dried), or left untreated (raw) and then planted with gel in loamy sand and sandy soils. There was little difference in response from the tomato seed treatments. In pepper, germinated seeds emerged much earlier and established heavier plants. Differences in emergence due to seed treatments generally were greater in loamy sand than in sandy soil.
Enzyme-linked Immunosorbent Assay for the Detection of Tobacco Ringspot Virus in Pelargonium × hortorum1
Authors: Newhart Susan R. , Romaine C. Peter , Craig Richard
Published: August 2022

Several factors which influence the detection of tobacco ringspot virus (TRSV), by the enzyme linked immunosorbent assay (ELISA) in leaf extracts of geranium (Pelargonuim × hortorum Bailey), were examined. Crude leaf extracts could be used in ELISA to rapidly index geraniums for TRSV, providing measures were taken to minimize the effect of leaf substances which were inhibitory to the ELISA reaction. Optimal detection of TRSV (50 ng/ml) was obtained by extracting leaves in a 20-fold excess (w/v) of either 0.02M phosphate buffer, pH 7.4 containing 0.15M NaCl, 0.05% Tween 20, and 2% polyvinyl pyrrolidone or 0.1M phosphate buffer, pH 7.0 containing 4% polyethylene glycol. Clarification of the extract with polyethylene glycol and NaCl provided a 5-fold higher test sensitivity. ELISA proved useful for the detection of TRSV in both clonal and seedling geranium leaves as well as in geranium seed. The test was found to be more reliable than a bioassay for the detection of virus in the latent stage of infection.
Overcoming Dormancy in Lilium longiflorum Bulblets Produced in Tissue Culture1
Authors: Stimart Dennis P. , Ascher Peter D. , Wilkins Harold F.
Published: August 2022

Leaf emergence from bulblets of Lilium longiflorum Thunb. generated in vitro from bulb-scale explants incubated in the dark at either 25 or 30°C was enhanced by 3 stimuli: incubation at 4°C for 1 or more weeks after removal from culture; immersion in water at 45° for 30 minutes to 8 hours after removal from culture; or in vitro red-light irradiation. For maximum response, bulblets generated at 25° required longer treatments at either 45° or under red-light irradiation. On the other hand, bulblets generated in vitro at 30° responded least to incubation at 4°. Although all 3 environmental factors ended dormancy, variation in rates of leaf emergence and total percentage of bulblets with leaves at the end of the experiments suggested differences in the state of bulblet dormancy due to in vitro temperature and differences in the physiological action of the environmental stimuli promoting leaf emergence.
Root Initiation in Tomato Seedlings1
Authors: Aung L. H.
Published: August 2022

The initiation of root primordia on the primary root and hypocotyl of tomato seedlings (Lycopersicon esculentum Mill. cvs. Fireball, Epoch, and MD 412-4) was determined under controlled conditions. The first primordium of ‘Fireball’, ‘Epoch,’ and MD 412-4 seedlings was initiated on the primary root 5–6, 7, and 8 days, respectively, after seeding. Primordia on the hypocotyl were initiated acropetally, after initiation on the root. Root initiation in ‘Epoch’ and MD 412-4 lagged behind ‘Fireball’, but the general pattern was similar. Hoagland’s nutrient solution significantly increased the number of primordia on the primary root and hypocotyl. Presoaking seed in 10 μm abscisic acid (ABA) or 6-benzylamino purine (BA significantly increased the number of primordia on the primary root. Application of 50 μ1 of 1 mm 2,3,5 triiodobenzoic acid (TIBA) in lanolin 1 cm below the cotyledonary node reduced the number of primordia on the hypocotyl.
Chemical Characteristics of Composted Hardwood Bark as they Relate to Plant Nutrition1
Authors: Albrecht Mary Lewnes , Watson Maurice E. , Tayama Harry K.
Published: August 2022

No differences were observed in the level of total acidity, total N and phenolic hydroxyl groups for samples of composted hardwood bark (fresh composted hardwood bark) and composted hardwood bark which had undergone further decomposition (aged composted hardwood bark). Humic acid was extracted from both fresh and aged composted hardwood barks. Yield of humic acid was greater for the aged bark, and there was an increase in the reactive functional groups which are involved in micronutrient chelation (carboxyl groups increased from 2.69 to 3.59 meq/g; phenolic hydroxyls increased from 7.82 to 10.29 meq/g). Alcoholic hydroxyl groups in fresh composted hardwood bark decreased from 2.03 to 0.01 meq/g with aging. From leaching studies it was determined that 0.5 meq/g Cu+2 was bound per gram of dried, fresh bark. Nutrient uptake studies showed that there was a reduction in the foliar nutrient concentration for Lolium multiflorum Lam. for increased cropping time when grown in aged, composted hardwood bark.
Slow-release Fertilizers Optimize Mycorrhizal Development in Container-grown Pine Seedlings Inoculated with Pisolithus tinctorius1
Authors: Maronek Dale M. , Hendrix James W. , Cornelius Paul L.
Published: August 2022

Seedlings of pitch pine (Pinus rigida mill.) and Virginia pine (P. virginiana mill.) were grown with and without inoculum of the ectomycorrhizal fungus Pisolithus tinctorius [(Pers.) Coker & Couch] in a sphagnum peatmossperlite medium supplemented with various rates of the slow-release fertilizer (18N–2.5P–10K Osmocote or single rates of 14N–6P–11.6K Osmocote and 19N–3P–8.3K Sierrablen plus ON–19.8P–OK superphosphate) or a soluble 20N–8.6P–16.4K fertilizer treatment. Mycorrhizal development was evaluated after 5 months of growth and then after a 3-month cold storage period. Seedlings heavily mycorrhizal with P. tinctorius and of acceptable planting size were produced with 2.3 to 4.5 kg 18N–2.5P–10K Osmocote/m3 medium. Higher fertilizer rates reduced or eliminated mycorrhizal development and reduced plant growth. Seedlings grown with soluble fertilizer were comparable in size to those produced with slow-release fertilizers, but mycorrhizal development was eliminated. The 3 slow-release fertilizer formulations produced seedlings of comparable size and mycorrhizal development. Superphosphate with or without slow-release or soluble fertilizer did not influence seedling growth or mycorrhizal development. Mycorrhizae continued to develop while plants were in cold storage. The ITW One-Way tube produced seedlings equal in size to those produced in the Leach Pine Cell, but mycorrhizal development appeared to be more sensitive to high fertilizer rates with the ITW tube. Mycorrhizal development did not affect seedling size.
A Rapid Method for Evaluating Curing Progress in Sweet Potatoes1
Authors: Walter William M. , Schadel William E.
Published: August 2022

Freshly harvested sweet potatoes [Ipomoea batatas (L.) Lam. c. Jewel] are cured by holding them at 80–95% relative humidity and 29.4°C for 5 to 7 days. Curing heals wounds inflicted during harvest, thus minimizing loss from microbial decay during subsequent storage. The wound healing process was followed by applying a saturated solution of phloroglucinol in strong acid (PG) to the underside of detached wound tissue and scoring the intensity of the color developed. Microscopic examination of companion tissue with PG showed that color intensity was due to the layers of cells in which PG positive material was deposited. Wound periderm formation was observed to occur simultaneously with development of the most intense color, indicating that the test may be useful in the evaluation of curing progress.
Effect of Oxytetracycline and Benzimidazole Treatments on Blight-affected Citrus Trees1
Authors: Lee R. F. , Timmer L. W. , Albrigo L. G.
Published: August 2022

Citrus blight is a vascular wilt disease of unknown etiology. Blight-affected ‘Pineapple’ sweet orange [Citrus sinensis (L.) Osb.] trees on rough lemon (C. jambhiri Lush.) rootstock in early stages of decline were treated with benzimidazole fungicides or with oxytetracycline (OTC) by trunk injection, soil drench, or injection plus drench. The distribution and persistence of the materials were monitored by bioassay using Bacillus cereus var. mycoides for OTC and Penicillium expansum L. for benzimidazoles. Both materials were well-distributed in the canopy following trunk injections, in the root systems following soil drenches, and though most of the tree after injection plus drench treatments. Benzimidazoles and OTC persisted within the trees for several months and relatively high levels of activity were maintained for over a year by 3 applications. OTC persisted in soil for more than 6 months; whereas, benomyl disappeared from the soil in 3 months or less. Although high levels of bactericidal or fungicidal activity were maintained in the treated trees, most treated trees declined as rapidly as the untreated control trees. The injection plus drench group treated with OTC showed a slight improvement after 2 years. None of the treatments increased tree growth or resulted in increased water uptake. High levels of zinc in trunk wood, an internal symptom of blight, were unaffected by the benzimidazole treatments, but injection plus drench treatment with OTC significantly reduced zinc levels in trunk wood. Since neither OTC nor benzimidazoles completely reversed symptoms of blight, we were unable to conclusively confirm or refute proposed bacterial or fungal etiologies for citrus blight.
Effectiveness of Fluidized Bed Material as a Calcium Source for Apples1
Authors: Korcak R. F.
Published: August 2022

Fluidized bed material (FBM), a dry, high Ca, alkaline waste product which results from combining coal and limestone, was used as the sole source of Ca for ‘York Imperial’ apples (Malus domestica Borkh.) grown in outdoor sand cultures over 3 growing seasons. FBM treatments were compared to gypsum, applied at similar rates based on apple tree Ca requirements, and to a no Ca amended control. Over 3 years, leaf Ca was significantly enhanced by increasing levels of FBM. FBM was a better Ca source compared to gypsum applied at similar rates only during the third year. Fruit flesh Ca and the incidence of cork spot were not significantly or consistently affected by treatments. There were no visual or nutrient deficiencies or toxicities noted from the FBM nor were yields and average fruit size affected.
Weed Control Systems for Narrow and Wide Row Snap Bean Production1
Authors: Teasdale John R. , Frank J. Ray
Published: August 2022

Five field experiments compared weed control systems for snap bean (Phaseolus vulgaris L.) production in 25-cm rows including herbicides, but no cultivation, to systems for conventional 91-cm rows including both herbicides and cultivation. Herbicide combinations of EPTC + dinoseb each at 3.4 kg/ha, EPTC at 3.4 kg/ha + bentazon at 0.8 kg/ha, and trifluralin at 0.6 kg/ha + bentazon at 0.8 kg/ha provided excellent control of annual weeds and yellow nutsedge in most experiments. With the most effective herbicide treatments, weed control was similar in 25-cm and 91-cm rows. However, when herbicide treatments failed to control all weed species, weed control in 91-cm rows was better than that in 25-cm rows, because 91-cm rows were cultivated. Snap beans in 25-cm rows yielded an average of 25% higher than snap beans in 91-cm rows (plant density was equivalent at both row spacings). As weed control improved, the magnitude of the yield difference between 25-cm and 91-cm row spacings increased.
Effect of Protective Covers on Cold Acclimation and Survival of Hybrid Tea Roses1
Authors: Rose A. E. , Pellett N. E. , Aleong John
Published: August 2022

Rosa hybrida L. ‘Peace’ and ‘Garden Party’ plants covered with mulch in October and November for 2 weeks were less cold-hardy, based on laboratory freezing studies, than unmulched plants. Subsequently, field injury of mulched stems was observed in December and January. Plants covered in mid-December were less cold-hardy than unprotected plants but exhibited less field injury in January than October- and November-mulched plants. Plants covered with Styrofoam cones were not injured as early as perlite-covered plants. There was no significant difference in winter injury when stems were covered with perlite, soil, or leaves. Unprotected plants had less winter stem injury than covered plants during the winter of 1978–79, when the plants were covered with snow. The following winter there was little snow cover, and November- and December-covered plants had significantly less winter stem injury in January than plants with no cover.
Factors Influencing Absorption of 14C(2-chloroethyl)phosphonic Acid by Leaves of Cherry1
Authors: Flore J. A. , Bukovac M. J.
Published: August 2022

14C(2-chloroethhyl)phosphonic acid (ethephon) was readily absorbed by leaves of cherry (Prunus cerasus L. cv. Montmorency: Prunus avium L. cv. Windsor, Napoleon). Penetration was greater (20–25 ×) through the abaxial than the adaxial surface, in light than in dark, and for ‘Windsor’ and ‘Napoleon’ than for ‘Montmorency’. Penetration was temperature-dependent, increasing 55 × between 15–35°C. The addition of a surfactant (X-77) increased wetting and penetration (+ 65%). Radioassay of ethylene released after 14C-ethephon treatment indicated that most of the ethylene (>80%) was derived from ethephon and not endogenously produced. The significance of these findings in relationship to field application is discussed.
Effect of Root Temperature and Photoperiod on Growth and Crop Productivity Efficiency of Petunia1
Authors: Merritt Richard H. , Kohl Harry C.
Published: August 2022

Seedlings of Petunia hybrida cv. Snow Cloud were subjected to root zone temperatures at the bottom surface of the pots of 15.6° to 19.4°C (NT) or 21° to 35° (HT) and photoperiods of 9 (SD) or 13 hr (LD) for 25 days in a eontrolled-environment chamber with air temperatures of 21° for 9 hr and 15.6° for 15 hr. HT × LD plants produced the largest total leaf area, largest main stem leaves, and most dry weight of all treatments; they were tallest and bloomed first, but had the fewest lateral branches. HT × SD plants developed the most lateral branches at the fastest rate and had a total leaf area, dry weight gain, and root development comparable to those of the LD treatments. NT × SD plants were the smallest. Crop productivity efficiency was determined to be NT × SD = 2.9%, HT × SD = 3.4%, NT × LD = 3.7%, and HT × LD = 3.9%.
Effects of Temperature and Low Oxygen Atmospheres on Respiration, Chip Color, Sugars, and Malate of Stored Potatoes1
Authors: Sherman Mark , EWing Elmer E.
Published: August 2022

Following curing and a period of storage at 10°C, potato (Solanum tuberosum L.) tubers were stored for 4 to 5 weeks at 1° or 10° in controlled atmospheres consisting of either air, 2.5% O2 (balance N2), or N2. CO2 production of tubers stored in air at 10° was relatively constant. When tubers were stored in air at 1°, CO2 production initially was lower than at 10° in air. It then increased to a maximum after about 15 days and eventually declined again. Storage in 2.5% O2 or N2 prevented the increase in CO2 production that occurred after several days of storage in air at 1°. Malate and citrate were the only organic acids detected in significant amounts in juice extracted from tubers when experiments were terminated. Changes in citrate showed no consistent trends. Tubers stored in air at 1° had higher sucrose, fructose, glucose, and malate levels than tubers stored at 10°. Storage in N2 at 1° prevented the malate, sucrose, and reducing sugar increases. Storage in 2.5% O2 inhibited the malate, fructose, and glucose increases at 1° and reduced the sucrose content of ‘Monona’ and ‘Norchip’ cultivars, which accumulated large amounts of sucrose during storage in air at 1°. Sucrose content of ‘Kennebec’ was not affected by 2.5% O2. Storage in 2.5% O2 slowed the accumulation of fructose and glucose, but only ‘Monona’ and ‘Norchip’ yielded acceptable chips after storage in 2.5% O2 at 1°. All 3 cultivars yielded acceptably colored chips after storage in N2 at 1°, but the development of blackheart when tubers were returned to air makes N2 an unacceptable storage atmosphere at this temperature. Storage in N2 resulted in soft rot at 10°.
Influence of Summer Pruning and Tree Orientation on Net Photosynthesis, Transpiration, Shoot Growth, and Dry-weight Distribution in Young Apple Trees1
Authors: Myers S. C. , Ferree D. C.
Published: August 2022

Young, actively growing, container-grown Malling Merton (MM) 106 apple trees (Malus domestica Borkh.), trained to a single shoot in a greenhouse, were oriented at vertical, 45° from vertical (45°), 90° from vertical (90°), or 90° from vertical and rotated at 1 rpm (90° rotated), and summer-pruned to remove none or 50% of 70.0-cm shoots. Orientation in a nonvertical position and summer pruning delayed a decline in net photosynthesis (Pn) exhibited by vertical unpruned trees. Pruning but not orientation increased total shoot growth, shoot number, and the number and total area of leaves of subsequent growth, but decreased average leaf size. Within 1 week after orientation, unpruned trees at 45° or 90° showed a decline of terminal shoot growth. However, 60 days after pruning a delayed growth of axillary shoots along the tree axis resulted in no difference in total shoot growth, leaf area, or leaf number on subsequent growth compared to vertical unpruned trees. Orientation at 45° and 90° increased the dry-weight root:shoot ratio and induced rootsuckers. Pruning decreased the root dry weight in all tree orientations. Rotation of unpruned trees increased apical growth, axillary shoot numbers, and dry weight of subsequent growth, and decreased root growth compared to unrotated trees.
Basis for Enhanced Softening of Snap Beans (Phaseolus vulgaris L.) from Postharvest Exposure to Carbon Dioxide1
Authors: Buescher R. W. , Adams K.
Published: August 2022

Postharvest exposure of snap beans to elevated CO2 (40%), but not reduced O2 (2.5%), enhanced softening when the pods were subsequently heated. Softening and solubilization of pectic substances induced by CO2 were related to lowered hydrogen ion concentrations, which were caused by the depletion of malic acid. In contrast, high CO2 stimulated succinic acid accumulation but did not alter citric acid levels. Blanching and boiling reduced the content of both succinic and malic acids in pods. Transelimination was effective in depolymerizing and solubilizing pectic substances in snap bean pods. The shift in pH induced by CO2 increased the transelimination reaction and thus increased pod softening.
Effects of Ethephon-gibberellin Combinations on Yield, Size, and Quality of Muskmelon1
Authors: Batal K. M.
Published: August 2022

Mixtures of (2-chloroethyl)phosphonic acid (ethephon) plus gibberellic acid (GA3) were applied to ‘Edisto-47’ muskmelon (Cucumis melo L.) plants at the 3–4 true leaf stage for 3 growing seasons. Ethephon at 240 mg/liter + GA3 at 100 mg/liter consistently increased the marketable yield of melons over the control. However, at 480 mg/liter ethephon, increased GA3 concentration from 50 to 150 mg/liter decreased yields. Average fruit weight and lengthdiameter ratios were increased by all ethephon + GA3 combinations, compared to the untreated control. Increased soluble solids and sweetness by 240 mg/liter ethephon + 100 or 150 mg/liter GA3 combinations were associated with increased fruit weight.
Factors Controlling Intumescence Development on Tomato Plants1
Authors: Lang S. P. , Tibbitts T. W.
Published: August 2022

Plants of the cultivated tomato, Lycopersicon esculentum Mill. cv. Oxheart, and of the wild tomato, L. hirsutum Humb. & Bonpl., were maintained in a growth chamber within small Plexiglas boxes to produce intumescence (oedema) injury. Severe injury occurred when plants were exposed to air from a pressurized laboratory supply and slight injury after exposure to air drawn from outside. Injury was greater on plants with 5 liters/min of air passing through the exposure boxes than with 1 liter/min. Severe but similar types of injury were observed at 30, 80, and 92% relative humidity (RH) levels. This is in contrast to previous research, which demonstrated that high humidity caused injury. Severe injury occurred at all irradiation levels evaluated—80, 240, and 400 µmol s−1m−2 (PPFD)—for a 16-hour light period. Exposure to toxic air from the laboratory supply lines during either the light period or the dark period resulted in similar amounts of injury. Continuous exposure caused greater injury. Injury developed consistently under Cool-White fluorescent lamps with a UV-B absorbing barrier between the lamps and plants, but no injury occurred if the barrier was not present. UV-B irradiation of the air before it was supplied to the plant chamber did not prevent injury.
Correlative Effects of Bench Chip Budded ‘Mirandy’ Roses1
Authors: Yui-Sing Fann , Davies Fred T. , Paterson D. R.
Published: August 2022

Bench chip budding was tested as an alternative to T-budding of roses in field bush production. Greater than 90% success was obtained when ‘Mirandy’ scions (Rosa hybrida L.) were bench chip budded to rooted ‘Brooks 56’ R. multiflora Thunb. rootstocks with a Liliput budding tool. Growth of chip budded scions was inhibited by the presence of rootstock lateral shoots. This correlative inhibition was overcome by selected forcing, girdling, and pruning treatments to promote vigorous scion growth. Best chip bud growth was obtained when scions were budded onto the same side as rootstock lateral shoots and rootstock stems were partially cut or girdled. A positive correlation existed between ‘Mirandy’ scion shoot growth and flowering.
Auxin Transport in Dracaena marginata Stems1
Authors: Saltveit Mikal E. , Fonteno William C.
Published: August 2022

Basipetal auxin transport occurred in intact and excised Dracaena marginata stem sections at an apparent velocity of about 5 mm/hr. Application of 20 µl of 0.1 mm 2,3,5-triiodobenzoic acid (TIBA) to the basal cut end of a 3-cm stem segment excised 20 cm from the apex of 1-m-tall plants reduced basipetal auxin transport by 60%. Similar application to the apical end had no effect on acropetal auxin movement. Lateral auxin movement was observed 24 hours after application of radioactive auxin to decapitated stems which had grown horizontally for at least 30 days.
Movement of Photosynthates in Muskmelon Plants1
Authors: Hughes D. L. , Bosland Judy , Yamaguchi M.
Published: August 2022

Individual leaves of Cucumis melo L. acropetal to a developing fruit were treated with a pulse of 14CO2. The level of 14C in the leaves, internodes, and fruits was determined after various periods of time when the leaf at the 3rd node acropetal to the fruit was treated. Leaves at the same node as the fruit, the 2nd, the 3rd, the 6th, and the 18th node acropetal to the fruit were treated and the level of 14C in the leaf, internodes, and fruit was determined after 2 hours. The percent of the incorporated 14C which was exported from the leaf was strongly affected both by time and leaf position relative to the fruit. Leaves which were 3 nodes acropetal to the fruit exported 65% of the label in 6 hours, while those further from the fruit retained the label longer. The influence of the fruit on the movement of 14C label is limited to a few internode lengths along the branch.
Enhancement of Growth and Phosphorous Concentrations in Apple Seedlings by Vesicular-arbuscular Mycorrhizae1
Authors: Hoepfner E. F. , Koch B. L. , Covey R. P.
Published: August 2022

Glomus mosseae (Nicol & Gerd.) Gerd. & Trappe, inoculation increased apple (Malus domestica Borkh.) seedling growth in 3 of 5 fumigated orchard soils without supplemental phosphorous. Mycorrhizae improved seedling growth in only one soil receiving additional P. Increasing P rates up to 100–200 mg/kg improved growth in only one soil receiving additional P. Increasing P rates up to 100–200 mg/kg improved growth of nonmycorrhizal-treated apple seedlings in 4 of 5 soils tested. The 5th soil had an adequate P content, 60 mg/kg soil prior to the addition of P. Mycorrhizal root infection of seedlings growing in soil that received G. mosseae inoculum decreased with increased P rates applied. Some infection was found in seedlings from all soils inoculated with mycorrhizae at P rates of 0–400 mg/kg, and seedlings from 2 of the mycorrhizal soils had infection at the P rate of 600 mg/kg.
Anatomical Indices of Cultivar and Age-related Scab Resistance and Susceptibility in Pecan Leaves1
Authors: Wetzstein Hazel Y. , Darrell Sparks
Published: August 2022

Structural differences in leaves of pecan [Carya illinoensis (Wang) K. Koch] of cultivars resistant and susceptible to the scab pathogen, Cladosporium caryigenum (Ell. et Lang) Gottwald com. nov (formerly designated Fusicladium effusum Wint.), were examined using scanning and transmission electron microscopy. In immature leaf tissue, cultivar resistance was correlated with fewer peltate glandular trichomes, a greater frequency of collapsed trichomes, and abundant phenolic compounds in the palisade parenchyma and bundle sheath cells compared to susceptible cultivars. In mature, scab-resistant leaves of all cultivars, trichomes were collapsed and less numerous, phenolics were abundant, and cuticular and epidermal cell wall development was greater compared to that of immature leaves.
Leaf Area and Fruit Size on Girdled Grapefruit Branches1
Authors: Fishler Michal , Goldschmidt Eliezer E. , Monselise Shaul P.
Published: August 2022

The dependence of fruit growth of grapefruit (Citrus paradisi Macf.) upon leaf area was investigated on girdled branches by manipulating leaf and fruit numbers. Leaf areas of 2.0 ± 0.5 m2 per fruit were found to be saturating with regard to fruit growth rate and size. Fruit on internal, shaded branches required larger leaf areas. Fruit on girdled branches weighed 44 to 119% more than fruit in ungirdled branches, which had leaf areas of 0.35 to 0.55 m2 per fruit. This indicates that leaf area is one of the factors limiting fruit growth. Starch accumulated in thin twigs during the fruit growth season, forming a saturation curve similar to those obtained for fruit size when plotted against leaf area per fruit. Increasing leaf area per fruit could involve a decrease in photosynthetic activity, a possibility which now is being investigated further.
Screening Tests for Salt Tolerance in Lettuce1
Authors: Shannon M. C. , McCreight J. D. , Draper J. H.
Published: August 2022

The response of lettuce (Lactuca sativa L.) to salinity was studied in greenhouse tests. Seven-day-old seedlings were grown in solution culture with salinity (NaCl + CaCl2, 2:1 molar ratio) ranging from 0.6 to 26 decisiemens per meter (dS m−1). Fresh weight (FW) declined as salinity increased; root weight was not affected as much as leaf weight. Regression analysis of 30-day-old seedlings showed that FW was significantly reduced at 4.6 dS m−1. FW decreased an additional 4.5% for each dS m−1 increase above 4.6 dS m−1. Results were similar 60 days after growth, and were comparable to previous field studies. A screening test for salt tolerance in lettuce was developed using sand culture. Considerable variability exists among 85 U.S. lettuce cultivars and breeding lines irrigated with 5.6 to 6.2 dS m−1 solution. ‘Climax’, ‘Climax 84’, ‘Shawnee’, ‘Tom Thumb’, ‘Fulton’, and ‘Wintergreen’ were the most tolerant cultivars tested. ‘Bibb’, ‘Ruby’, ‘Gustoverde’, ‘Prizehead’, and ‘Big Boston’ were significantly more sensitive to salinity.
Factors Involved in the Development of Tipburn in Crisphead Lettuce in Hawaii1
Authors: Yanagi Ann A. , Bullock R. M. , Cho J. J.
Published: August 2022

Tipburn incidence, maximum and minimum ambient temperatures, and nutrient levels in outer, middle, inner, and core head sections of lettuce (Lactuca sativa L.) were monitored monthly from December 1979 to September 1980. Tipburn incidence was positively correlated with mean monthly maximum, average, and minimum temperatures and was negatively correlated with magnesium, calcium, and boron levels in the inner head sections.
Cranberry Quality: Selection Procedures for Breeding Programs1
Authors: Sapers G. M. , Phillips J. G. , Rudolf H. M. , DiVito A. M.
Published: August 2022

Samples of 45 cranberry clones (Vaccinium macrocarpon Ait.) were analyzed for factors relating to fruit quality and processability to develop selection procedures for breeding programs. High correlations were obtained between tristimulus reflectance measurements on whole or pureed cranberries and the juice color, determined by spectrophotometric or tristimulus transmission measurements. Differences between cranberry samples in the proportions of individual anthocyanins were small and not correlated with berry or juice color. A 3-stage sequence of simple measurements, entailing minimal sample preparation, was developed for selection. First- and second-stage selections were based on the application of discriminant analysis to tristimulus reflectance data obtained with whole and pureed cranberry samples, respectively. In the third stage, selections were based on analytical measurements performed on juice prepared from samples selected in the preceeding stages.
Effect of Mechanical Stress and Inhibitors of Protein Synthesis on Leaf Epinasty in Mechanically Stressed Poinsettia Plants1
Authors: Saltveit Mikal E. , Larson Roy A.
Published: August 2022

Periodic shaking increased the resistance of potted poinsettia (Euphorbia pulcherrima Klotzsch ex. Willd., cv. Annette Hegg Diva) plants to mechanically induced leaf epinasty, but this resistance was lost within 24 hours of discontinuing the shaking. Bending petioles, not their reorientation in the gravitational field, caused increased ethylene production by excised petioles. Foliar sprays containing 40 μm cycloheximide, which were applied 24 hours before the plants were sleeved for 24 hours, completely prevented mechanically induced leaf epinasty, but were phytotoxic to the bracts.
Morphology and Anatomy of Intumescence Development on Tomato Plants1
Authors: Lang S. P. , Esther Struckmeyer B. , Tibbitts T. W.
Published: August 2022

Plants of Lycopersicon esculentum Mill cv. Oxheart, the cultivated tomato, and L. hirsutum Humb. & Bonpl. PI LA 1625, a wild tomato, were placed in small Plexiglas boxes in a growth chamber and exposed to air from a pressurized laboratory supply line to induce intumescence injury. External symptoms of injury on the 2 species were different, but anatomical responses were similar. Injury on L. hirsutum consisted primarily of gall-like protrusions 1-2 mm in diameter on leaves, whereas symptoms on L. esculentum consisted primarily of callus-like tissue on petioles, midribs, and stems. Some injury of each type was found on both species. When severely injured, leaves wilted and abscised on L. esculentum, but not on L. hirsutum. Where injury occurred, the epidermis and underlying 2 or 3 layers of cells hypertrophied and produced intumescences. Vascular tissue of L. esculentum exhibited tyloses which occluded xylem vessels, apparently blocking water transport and causing wilting and abscission of leaves.
Inheritance and Associations of Leaf, External, and Internal Pod Reactions to Common Blight Bacterium in Phaseolus vulgaris L.1
Authors: Valladares-Sanchez Nicolas E. , Coyne Dermot P. , Mumm Robert F.
Published: August 2022

A 6-parent Phaseolus vulgaris diallel cross was produced to determine the inheritance of leaf, external, and internal pod reactions to the bacterial pathogen Xanthomonas campestris pv. phaseoli (Smith) Dye = Xanthomonas phaseoli E.F.S. Dows (X.p.) Nebraska isolate EK-11. The parents and F1 generations were grown in the greenhouse, whereas the F2, along with parents, were also grown in the field at 2 locations (Lincoln and Scottsbluff, Neb.). The Gardner and Eberhart (1966) model, Analysis II, was used to obtain estimates of the genetic effects for the reactions to the pathogen in the different plant parts. Coefficients of variation were high in the greenhouse experiment and low in both field experiments. The increased precision of the field experiments allowed more genetic effects to be detected as being significant. The leaves of ‘Great Northern (GN) Nebraska #1 sel. 27’ and Plant Introduction (PI) 207262 were resistant, ‘Tacarigua’ moderately susceptible, and PI 163117, ‘GN 1140’, and ‘Guali’ were highly susceptible. The pods of the first 3 entries, along with ‘GN 1140’ showed moderate resistance, but the internal reaction of the pods of ‘GN Nebr. #1 sel. 27’ showed more susceptibility than the external reaction. The reaction to X.p. was quantitatively inherited in all experiments. Additive effects were primarily involved in the genetic control of the leaf, external, and internal pod reactions to X.p. Heterosis effects for leaf reaction were detected under field conditions. External and internal pod reactions were highly correlated, but little association between leaf and pod reaction was observed. It is, therefore, necessary to select for resistance simultaneously in both plant parts since correlated responses are not expected to be present. Large positive correlations were detected between the reactions of genotypes observed in the greenhouse with those in the field experiments and between the field experiments, indicating that greenhouse tests should adequately predict field performance. A significant genotype × location interaction for leaf reaction was detected, with ‘Guali’ and ‘Tacarigua’ being more susceptible at Lincoln, under higher night temperatures, than at Scottsbluff, indicating the importance of evaluating the reaction of germplasms to this pathogen in different environments.
Enhanced Rooting of Wounded Mung Bean Cuttings by Wounding and Ethephon1
Authors: Robbins James A. , Kays Stanley J. , Dirr Michael A.
Published: August 2022

Rooting of light-grown cuttings of mung bean [Vigna radiata (L.) R. Wilcz.] was stimulated by wounding and by the ethylene-releasing compound (2-chloroethyl)phosphonic acid (ethephon) at 0.1, 1.0, and 10.0 mg/liter with a maximum response at 1 mg/liter. The inhibitor of ethylene synthesis, aminoethoxyvinylglycine (AVG), at 10 µm, significantly decreased root number in wounded cuttings, but ethephon overcame this inhibition. Rooting in wounded cuttings was stimulated by indolebutyric acid (IBA) at a concentration of 5 × 10−6 m but root numbers decreased by 56% with AVG + IBA. Application of ethephon or IBA, and extensive wounding, caused an upward redistribution of roots away from the base of the cuttings.
Growth Measurement as an Indication of Avocado Maturity
Authors: Lee S.K. , Young R.E.
Published: August 2022

Fruit growth of avocado (Persea americana Mill.) fruit measured by the increase in length, diameter, and volume was initially rapid, but later slowed to a linear growth. Linear extrapolation to zero from growth rate in the descending portion gave a definite point indicating that physiological maturity had occurred. In many cases, this physiological maturity date correlated well with horticultural maturity date determined by taste-panel analysis.
Effect of Genetic Relationship to Pollinizer on Fruit, Seed, and Seedling Parameters in Highbush and Rabbiteye Blueberries
Authors: Hellman E.W. , Moore J.N.
Published: August 2022

Cultivars of 5 highbush (Vaccinium corymbosum L.) and 5 rabbiteye (Vaccinium ashei Reade) blueberries were each pollinated with a series of cultivars of varying genetic relationship. A significant reduction in mean berry weight was associated with an increase in the degree of relationship between parents for one highbush and one rabbiteye cultivar. The mean number of seed per berry was significantly reduced and was associated with an increase in the degree of relationship for 3 highbush and 2 rabbiteye cultivars. Level of inbreeding did not affect percentage seed germination. Two highbush cultivars demonstrated a significant reduction in mean seedling fresh weight associated with an increase in the level of inbreeding. Rabbiteye seedling vigor data were insufficient to draw any conclusions on inbreeding effects. Variability of cultivars in response to cross-pollination among related individuals suggests that other factors may be more influential in some instances.
Polyuronide Degradation and Hemicellulose Modifications in Ripening Tomato Fruit
Authors: Huber Donald J.
Published: August 2022

Hemicelluloses and polyuronides from the cell wall of ripening tomato (Lycopersicon esculentum Mill. cv. Rutgers) fruit were examined using gel-filtration chromatography. Gel filtration of polyuronides revealed that these polymers were extensively degraded during ripening, as evidenced by the increase in the quantity of polymers that fractionated on the gel. Low molecular weight polyuronides were first evident in fruit harvested at the turning stage and they constituted the major portion of the polyuronides obtained from fruit at more advanced stages of ripening. The appearance of degraded polyuronides corresponded well with the activity of endo-D-galacturonanase, which appeared to be solely responsible for the degradation of these wall polymers. The cell wall hemicelluloses were also affected during ripening; gel-filtration analyses revealed marked changes in the molecular-weight distribution of these polymers. Hemicelluloses from immature green and mature green fruit were similar chromatographically, whereas those from fruit harvested during ripening showed progressively lower quantities of high molecular weight polymers and higher quantities of low molecular weight polymers (<40,000). These changes coincided with the degradation of the pectic polysaccharides; however, in vitro studies using isolated cell wall showed that pectin degradation occurred independently of the changes in hemicelluloses.
Reducing Injury during Mechanical Harvesting of Cranberries
Authors: Davis Denny C. , Shawa Azmi Y.
Published: August 2022

Commercial harvesters of cranberry (Vaccinium macrocarpon Ait.) caused more berry injury than did a hand scoop. On the Furford Picker-Pruner the major berry injury occurs as the first elevator paddle contacts the berries. Modifications of the elevator on the Furford harvester significantly reduced cranberry harvesting injury on the elevator. Cranberry breakdown during a 5-week storage period was related to the prestorage berry injury level, but cranberry breakdown during an 8-week storage period was unrelated to injury level.
Incorporation of Tritiated Thymidine and Uridine into Adventitious-root Initial Cells of Vigna radiata
Authors: Tripepi Robert R. , Heuser Charles W. , Shannon Jack C.
Published: August 2022

Adventitious roots in mung bean [Vigna radiata (L.) R. Wilcz. cv. Berken] cuttings develop from specific “rooting-zone parenchyma” (R-ZP) cells. Microautoradiography was used to determine the timing of thymidine and uridine incorporation into the R-ZP cells, prior to the first cell division, in the presence or absence of naphthaleneacetic acid (NAA). Since 6-3H-thymidine incorporation reached a maximum between 11 and 14 hours, we suggest that the R-ZP cells were in the G1 phase when the cuttings were taken. Tritiated uridine was incorporated into the RNA of the R-ZP cells 2 hours after the cuttings were placed in the labeled solution. DNA synthesis and cell division of the R-ZP cells occurred along the entire length of the hypocotyl (basal, middle, and top segments), but these initial events were not sufficient to result in the subsequent formation of adventitious roots. NAA promoted adventitious root formation in the cuttings but it had no apparent effect on nucleic acid labeling nor initial cell division of the R-ZP cells. The initial division of the R-ZP cells appears to be a wounding response and occurs in the presence or absence of exogenous auxin.
Scanning Electron Microscopy of in Vitro-cultured Liquidambar styraciflua Plantlets during Acclimatization
Authors: Wetzstein Hazel Y. , Sommer Harry E.
Published: August 2022

The acclimatization or hardening-off of in vitro-cultured sweetgum (Liquidambar styraciflua L.) plantlets was studied using scanning electron microscopy. Comparisons were made among leaves of plantlets differentiated in culture, plantlets acclimatized after transfer from in vitro conditions, greenhouse seedlings, and mature trees. Leaves of plantlets directly from tissue culture had superficial, circular stomata and epidermal cells with irregular, sinuous undulations in the anticlinal walls. Leaves from acclimatized plantlets had ellipsoid, depressed stomata and irregularly shaped epidermal cells. Seedling and field-grown leaves had depressed, ellipsoid stomata and well-defined isodiametric epidermal cells. Stomata in all cases were confined to the abaxial surface, with densities significantly greater in leaves of in vitro plantlets than in acclimatized plantlets or greenhouse-grown plants. Epicuticular wax was generally smooth and absent of waxy outgrowths in all conditions.
The Histology and Histochemistry of the Wound-healing Process in Geranium Cuttings
Authors: Cline Molly Niedbalski , Neely Dan
Published: August 2022

The wound-healing process in cuttings of Pelargonium X hortorum L.H. Bailey cv. Yours Truly was studied using histological and histochemical techniques. Anatomical changes at the wounded surface of cuttings within 24 hours included deposition of a granular, amber-colored substance identified as suberin on the cell walls, in the intercellular spaces, and in the lumina of xylem vessels. Wound xylem, adventitious root primordia, and wound callus developed within 7 days. A periderm developed 14 to 21 days after wounding and its cell walls were suberized.
Optimum Potassium Nutritional Level for Production of Highbush Blueberry
Authors: Paul Eck
Published: August 2022

A field planting of ‘Bluecrop’, a mature highbush blueberry (Vaccinium corymbosum L.), on a Berryland soil type was subjected to differential levels of K fertilization over a 6-year period. Fruit yield and berry size were related to fertilizer treatment, leaf composition, and available soil K analysis. Blueberry production was highest at a 40 kg K/ha rate of potassium sulfate fertilizer which resulted in a leaf K sufficiency range between 0.45% and 0.55% K. Available soil K was significantly correlated to fruit yield.
The Effect of Benomyl, Sodium Hypochlorite, and Controlled Atmospheres upon the Incidence of Black Speck of Stored Cabbage
Authors: Walsh J.R. , Lougheed E.C. , Toivonen P.M.A.
Published: August 2022

In the 1979-1980 and 1980-1981 seasons, stored cabbage (Brassica oleracea L., Capitata group) developed symptoms of the disorder black speck. Dipping in 500 mg/liter benomyl and 95 or 190 mg/liter chlorine (as sodium hypochlorite) solutions increased susceptibility to the development of black speck, but control of ethylene levels and an atmosphere of 3% O2 + 5% CO2 had little effect. A slight difference was noted in cultivar susceptibility and in one season a dip in water appeared to decrease the occurrence of the disorder.