bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of Cytokinins on in Vitro Shoot Development of ‘Concord’ Grape1
Authors: Pool Robert M. , Powell Loyd E.
Published: August 2022

The growth of excised grape shoots in the absence of roots was investigated using asceptic culture. Sustained shoot development was observed only when cytokinins were present in the media. We used ‘Concord’ (Vitis labruscana Bailey) in most experiments, but the response was observed in other cultivars including those of Vitis vinifera L. Better response was obtained with cytokinin ribosides than with free bases. If roots developed, the requirement for an exogenous source of cytokinin was nullified.
Effect of Nitrogen Form and pH on Growth, NO3-N, NH4-N and Total N Content of Container-grown Doublefile Viburnum1
Authors: Dirr Michael A.
Published: August 2022

Doublefile viburnums (Viburnum plicatum Miq. tomentosum Thunb.) were cultured at 2 pH ranges, 3 to 4 and 7 to 8, with 3 N treatments (NO3-N, NH4-N, or NO3-N plus NH4-N) supplied daily at a concentration of 1.5 meq N per pot. Fresh weights of shoots and roots from plants grown with NH4-N at pH 3 to 4 were significantly lower than from plants grown with other N treatments. Plants developed leaf necrosis and ultimately died when grown with NH4-N at pH 3 to 4. Limited leaf necrosis developed on other NH4-N treated plants. Leaf necrosis did not develop on leaves of plants grown with NO3-N at pH 3 to 4 or 7 to 8. Roots of all plants, except those grown with NH4-N at pH 3 to 4 appeared vigorous and healthy. Nitrate N was greatest in shoots of NO3-N treated plants. Shoot NH4-N levels were greatest in NH4-N treated plants and correlated with the severity of leaf necrosis. Total N concentration in shoots and roots were greatest in plants grown with NO3-N at pH 3 to 4 and NO3-N plus NH4-N at pH 3 to 4. In the growing medium, NO3-N predominated at the high pH range; NH4-N at the lower pH range. The N form and pH of the growing medium exerted marked effects on growth, and on N availability and utilization by viburnum.
In Vitro Culture of Rudimentary Embryos of Eleven Ilex Species1
Authors: Hu C. Y.
Published: August 2022

The heart-shaped embryos, dissected from mature fruits of 11 Ilex (holly) species in 4 taxonomic sections, grown in modified White’s and Linsmaier and Skoog’s media jelled with Bacto-agar, produced seedlings. The rudimentary embryos were sufficiently autotrophic that a carbon source was the only organic compound needed in the media. There is a great variation in speed of in vitro development among individual embryos of the same species. The average embryo length of I. aquifolium L. increased linearly and most embryos reached germination size at the 55th day of incubation. The average embryo length of I. cornuta Lindl. increased sigmoidally and most embryos reached germination size at the 23rd day of incubation. The in vitro germination percentages for most species were above 80%. The survival rates after transplanting were higher than 75%. Sub-sequent seedling growth in greenhouses was healthy and vigorous.
Effect of Trellis Height with and without Crossarms on Yield of Thompson Seedless Grapes1
Authors: Weaver Robert J. , Kasimatis A. N.
Published: August 2022

‘Thompson Seedless’ grapes (Vitis vinifera L.) were trained to heights of 1.4, 1.7, and 2.0 m with and without an 0.6-m crossarm. Data were collected from 4 seasons beginning in 1969. Within treatments variability was usually too great to reveal significant differences among treatment means for most parameters measured within a single year. Analysis of the 3-year combined results revealed that the highest trellis resulted in most yield, most clusters, and most berry sugar per vine. Vines on the lowest trellis had the least pruning brush wt. Vines with crossarms had higher wt per berry, soluble solids, sugar, and wt brush per vine than did vines without crossarms.
Use of Ethephon and Chlorflurenol in a Once-Over Pickling Cucumber Production System1
Authors: Cantliffe Daniel J. , Phatak Sharad C.
Published: August 2022

Ethephon and chlorflurenol were applied to hybrid pickling cucumber Cucumis sativus L. cvs. Pioneer and Pickmore to study the use and effectiveness of the chemicals on promoting fruit yields and quality in a once-over harvest system. Ethephon was applied either at the first or the fourth true-leaf stage of growth. Chlorflurenol was applied at 0, 50 or 100 ppm when 6-8 female flowers reached anthesis. Dollar value per ha was increased by approximately 14% when ethephon or chlorflurenol was used alone. However, when these 2 growth regulators were used in combination, yields were increased by as much as 68% in ‘Pioneer’ and 40% in ‘Pickmore.’ Chlorflurenol significantly increased the number of fruit per plant and reduced the length to diameter ratio. Fruit shape and L:D ratio were significantly improved when ethephon was applied in the fourth true-leaf stage regardless of chlorflurenol usage. Chlorflurenol slightly reduced the fresh quality of ‘Pioneer’ but had no such effect on ‘Pickmore.’ Salt stock quality was improved slightly by chlorflurenol. To obtain best yield, fruit shape, fresh salt stock quality, ethephon should be applied twice, 1 week apart commencing at the fourth true-leaf stage, followed by a 50 to 100 ppm spray application of chlorflurenol when 6-8 female flowers have reached anthesis.
Effect of Soil Moisture and Irrigation Method on Tipburn and Edgeburn Severity in Greenhouse Lettuce1
Authors: Bert John S. , Honma S.
Published: August 2022

Lettuce (Lactuca sativa L.) cvs. Domineer and Grand Rapids were grown in the greenhouse at 4 soil moisture levels using 2 irrigation methods. Tipburn developed on immature ‘Domineer’ plants but not on ‘Grand Rapids’ in the high soil moisture beds 63 days after transplanting. Tipburn was observed on both cultivars when harvested at maturity 93 days after transplanting. Mature plants of ‘Domineer’ were more severely tipburned than those of ‘Grand Rapids.’

Edgeburn was first observed 53 days after transplanting on both cultivars at all soil moisture levels as pinpoint necrosis on outer leaves where the veins terminate at the leaf edge. The affected area enlarged with time and appeared to be associated with high levels of Mn.

Yields were higher at the 0.0–0.2 and 0.4 bar tension levels than at 2.0 bars. ‘Domineer’ gave higher yields than ‘Grand Rapids.’
Hormonal Control of Flower Bud Dormancy in Sour Cherry (Prunus cerasus L.). II. Levels of Abscisic Acid and its Water Soluble Complex1
Authors: Mielke E. A. , Dennis F. G.
Published: August 2022

Levels of both free abscisic acid (ABA) and its soluble complex, assumed to be the l’-glucose ester (“bound” ABA), were measured by electron-capture gas-liquid chromatography in the scales and floral primordia of sour cherry. On a per bud basis, more ABA was found in the scales than in the primordia, although the concentration was greater in the primordia. Concentrations of bound ABA were greater than those of free ABA. The concentration of free ABA changed more dramatically in the primordia than in the scales, rising rapidly in the fall, reaching a maximum in Nov. or Dec., then declining rapidly (ca. 4 wk) to or below the original level. The autumn increase was coincident, not with the onset of dormancy, but with the onset of leaf abscission, maximum levels occurring when about 90 to 95% of the leaves had abscised. In addition, free ABA returned to its original level several weeks prior to the termination of rest. Levels of bound ABA paralleled those of free ABA, but declined more slowly during early winter.
Cherry Fruit Abscission: A Role for Ethylene in Mechanically Induced Abscission of Immature Fruits1
Authors: Wittenbach V. A. , Bukovac M. J.
Published: August 2022

Mechanical injury to the seed of immature sour cherry (Prunus cerasus L., cv. Montmorency) fruit caused an immediate and marked increase in ethylene evolution followed by abscission of the fruit at the peduncle: pedicel zone. Ethylene evolution was induced when the seed, but not the pericarp, was injured. The magnitude of ethylene evolution was related to stage of fruit development at time of injury, and was most pronounced when the nucellus was the dominant tissue in the seed. Ethephon (500 and 1000 ppm) also caused immature fruits to abscise and abscission was preceded by embryo abortion. The site of ethephon-induced fruit separation differed depending on stage of fruit development at time of treatment. Fruit separation occurred at the peduncle:pedicel abscission zone when immature fruits were treated, and at the pedicel fruit zone when mature fruits were treated. The role of ethylene in the abscission of immature sour cherry fruit is discussed.
Developmental Anatomy of Interlocular Cavitation in Snap Beans Phaseofus vufgaris L.1
Authors: Lee Jung M. , Read Paul E.
Published: August 2022

Developmental anatomy of interlocular cavitation (IC), defined as the formation of cavities in soft parenchymatous endocarp cells between seed locules4, was studied in pods of several snap bean cultivars grown under various cultural and environmental conditions during the years 1969–1972. IC occurred in pods from the stages of rapid pod elongation (6–10 days after anthesis) until the time of pod senescence. Unbalanced swelling of endocarp tissues combined with decreased periclinal cell division and rapid cell elongation are concluded to be the causes of IC. In the most commonly observed form, IC also includes the separation of fused endodermal cells. Pod malformation is greater in pods with severe IC and such pods exhibited more quality defects after processing. Sequential development of this developmental and physiological disorder is illustrated.
The Water Conductivity of Defective Graft Unions in Pome and Stone Fruits1
Authors: Gur A. , Blum A.
Published: August 2022

Using heat pulses the apparent velocity of the transpiration stream was measured in apple (Malus sylvestris Mill.) grafted on French seedlings (M. baccata Desf.), and several cultivars of peach (Prunus persica Sieb. and Zucc.) and Japanese plum (Prunus triflora Roxb.) grafted on almond (Prunus amvgdalus Batsch.) rootstock. The trees varied in compatibility with their respective rootstocks, as established by visual observation and gross morphology of the zone of union. Velocity of the transpiration stream was measured in 3 regions of each tree: the rootstock stem, the zone of union, and the scion stem. In definitely defective unions velocity of the transpiration stream in the zone of union exceeded that in both rootstock and scion. The possible use of this method as a tool for identifying poor graft unions in orchards is evaluated.
Seasonal Nutrient Levels and Peach/Plum Graft Incompatibility1
Authors: Breen Patrick J. , Muraoka Tom
Published: August 2022

‘Lovell’ peach seedlings (Prunus persica Batsch.) and ‘Marianna 2624’ plum (P. cerasifera Ehrh. × P. munsoniana Wight & Hedr.) were spring budded with ‘Fay Elberta’ peach or ‘Marianna 2624’. ‘Fay Elberta’/‘Marianna 2624’ was the only incompatible graft combination and foliar symptoms of ill-health appeared in early August. Levels of N, P, K, Ca, and Mg in leaves and bark of the peach/plum trees before incompatibility symptoms developed were similar to those of compatible combinations. The concentration of foliar nutrients, however, was relatively low in trees with severe incompatibility symptoms. Foliar N and K levels fluctuated concurrently with the onset of decline symptoms on peach/plum trees. The concentrations of K, Mg, and Ca declined during the season in the scion bark of the incompatible combination but remained relatively unchanged in the rootstock bark. Among the 4 graft combinations, the level of P in the scion bark was greatest in peach/plum trees and its distribution profile down the bark was similar to that of inositol; both accumulated to the highest level immediately above the incompatible union.
Calcium Concentration of ‘Spartan’ Apple in Relation to Amount of Senescent Breakdown in Individual Fruits1
Authors: Mason J. L. , Drought B. G. , McDougald J. M.
Published: August 2022

The concentration of Ca in the flesh was closely related to the amount of breakdown in individual apples in 5 lots of ‘Spartan’ apple (Malus sylvestris Mill.) collected over 2 years. Correlation coefficients of 0.9 were obtained using log Ca and linear breakdown or log Ca and log breakdown. The amount of breakdown calculated for the 5 lots by the 2 equations was 100 percent at 70 ppm Ca, from 46 to 100 percent at 100 ppm Ca, from 3 to 12 percent at 150 ppm Ca and less than 2 percent at 200 ppm.
Variations in Levels of Four Natural Growth Regulators During Growth and Flowering of ‘Gloria’ Azalea1
Authors: Sydnor T. Davis , Larson Roy A.
Published: August 2022

Three gibberellins; GA3, GA4, GA7; and abscisic acid (ABA) from the shoot tips of greenhouse grown ‘Gloria’ azaleas, Rhododendron sp.L., were tentatively identified using column chromatography, gas-liquid chromatography, and Rumex leaf senesence bioassay. Growth regulators were quantitatively estimated biweekly from 6 weeks after shoot tip removal until anthesis.

GA3 levels remained nominal for the normal commercial treatment until after plants were returned to 19°C from the 9° cooler. Endogenous GA3 levels then peaked at 0.6 μg/bud at anthesis. GA4 levels remained fairly constant for all treatments and times at 0.1 μg/bud. GA7 levels remained fairly constant below 2 μg/bud except in the cold-treated plants when endogenous GA7 levels peaked at 0.6 μg/bud at the time that plants were removed from the cooler.

ABA levels were similar until 24 wks. from pinch when the levels dropped to undetectable levels in cold-treated plants and increased in treatments not given a cold treatment by peaking at 0.1 μg/bud at 28 wks. from pinch.

Of the commercially available gibberellins that were monitored, GA7 seemed to be the best treatment for chemically overcoming flower bud dormancy in azalea.
Breeding Progress in Tomato with Pedigree Selection and Single Seed Descent1
Authors: Casali Vicente W. D. , Tigchelaar E. C.
Published: August 2022

Estimation of breeding progress in 9 tomato populations subject to 4 generations of pedigree selection revealed significant generation differences for 5 of 12 variables measured. Cross effects were of greater magnitude than generation effects with response to pedigree selection measurable only for highly heritable characters.

Mean value of lines derived from 2 or 3 generations of pedigree selection followed by single seed descent (SSD) to F6 or F7 were similar to their corresponding pedigree lines and approximately 50% of SSD lines derived following selection to F4 surpassed pedigree lines in weighted value. Early generation pedigree selection to F4 followed by selection among F6 SSD derived lines appears to be the most rapid and effective means of sampling variability in segregating populations.
Effect of Scion and Rootstock on Mineral Composition of Mandarin-type Citrus Leaves1
Authors: Smith Paul F.
Published: August 2022

Marked differences were found in the mineral composition of leaves from 8 closely related scions grown on 6 different rootstocks for 7 years. The scions were ‘Owari’ Satsuma mandarin (Citrus reticulata Blanco): ‘Orlando’ tangelo (C. paradisi Macf. × C. reticulata); ‘Robinson’, ‘Bower’, ‘Nova’, ‘6-9-10’ and ‘6-6-21’ hybrids of ‘Clementine’ tangerine × ‘Orlando’ (C. reticulata × (C. paradisi × C. reticulata)); and ‘Page’ hybrid of ’Minneola’ tangelo × ‘Clementine’ ((C. paradisi × C. reticulata) × C. reticulata). The rootstocks were rough lemon (C. limon (L.) Burm. f.); ‘Milam’, rough lemon hyb.?; sour orange (C. aurantium L.); ‘Rusk’ citrange (C. sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.); ‘Carrizo’ citrange (P. trifoliata × C. sinensis); and ‘Orlando, tangelo. The differences caused by scion or rootstock were of about the same magnitude.
Effect of Tree Density on the First Ten Years of Growth and Production of ‘Washington’ Navel Orange Trees1
Authors: Boswell S. B. , McCarty C. D. , Hench K. W. , Lewis L. N.
Published: August 2022

High density planting of tree crops has the potential of increasing yield and income during the early years of an orchard’s life. Eleven different planting densities of citrus were studied over a 10-year period to determine the effect of tree spacing on yield, tree growth, root distribution, nutrition, and economic factors involved. Extremely close plantings soon crowded to the point where they were unmanageable and tree removal became necessary. Pruning was needed to maintain a workable orchard in more moderatley spaced plots.
Influence of Plant Spacing on Yield of Muscadine Grape1
Authors: Brightwell W. T. , Austin M. E.
Published: August 2022

Plants set 6.1, 6.4 and 6.7 m apart in each of 3.0-, 3.7- and 4.3-m rows of the muscadine grape, Vitis rotundifolia, Michx., cv. Hunt, were compared for 25 years. The highest plant density, 477 plants/ha, gave the greatest yield per m2 almost consistently for 25 years. The highest yields per plant were obtained from the wider in-the-row spacings. Alternate bearing was rather consistent from 1949 through 1963, but irregular thereafter.
Phenotypic Analysis of Progenies of Artificial and Natural Amphiploid Cultivars of New Guinea and Indonesian Species of Impatiens L.1
Authors: Arisumi Toru
Published: August 2022

Phenotypic analysis of selfed and crossed progenies of colchicine induced and natural amphiploid cultivars of New Guinea and Indonesian Impatiens showed that the amphiploids were comparable to inbreds; i.e., seedlings within progenies were identical in nearly all of the floral, foliage, and plant characteristics studied. Most frequent Variation occured in patterns and intensity of flower colors.
Growth and Nutrient Response of Pecan Seedlings, Carya illinoensis Koch, to Nitrogen Levels in Sand Culture1,2,3
Authors: Sparks Darrell , Baker Donald H.
Published: August 2022

Growth of pecan seedlings in sand culture under various N levels (0 to 1260 ppm) induced N deficiency, normal growth, and N toxicity. Deficiency symptoms and N concentration of leaflets suggest N translocation does not occur from older to younger tissues or is minimal and that early growth is dependent on stored reserves of N. When growth exceeded N reserves, a “Steenbjerg effect” occurred, i.e., N concentration in leaflets decreased as growth increased. The symptom of N toxicity was an overall suppression of tree growth. Leaflet concentration of N was the best indicator of the N status of the tree; but, due to a diminishing return effect of N uptake to N supply, the N ranges associated with cardinal growth points were relatively narrow. Nitrogen application affected K, Ca, Mg, Mn, Cu, and Zn concentration in the leaflet.
Endogenous Plant Growth Substances in Developing Fruit of Prunus cerasus L. IV. Extractable Auxin in the Seed and Pericarp1
Authors: Hopping Murray E. , Bukovac Martin J.
Published: August 2022

Endogenous acidic and neutral growth-promoting substances were extracted from sour cherry (Prunus cerasus L. cv. Montmorency) seed and pericarp tissues, separated by ascending paper chromatography and detected by the Avena first internode bioassay. Although correlations were established between the levels of seed auxin and concomitant development of the nucellus and integuments and the development of the endosperm and embryo, no correlation was found between the levels of seed and pericarp auxin or between the level of pericarp auxin and concomitant fruit development.
Chimeral Structure of Red Sports of ‘Northern Spy’ Apple1
Authors: Pratt Charlotte , Way Roger D. , Einset John
Published: August 2022

Blushed-fruited sports of striped ‘Northern Spy’ apple (Malus pumila Mill.) are thought to have a mutation for this color pattern in layers I and II of the apical meristem. 1) Increased anthocyanin occurred in the epidermis (derived from L I) and in the hypodermis and outer flesh cells (derived from L II) of mature fruits of 5 sports. 2) One sport crossed with a yellow cultivar produced more blushed- than striped-fruited progeny, indicating that gene(s) for blush were in L II. 3) Three sports consistently produced blushed fruits in the orchard or following gamma irradiation of 3000–5000 rads applied to dormant buds, suggesting that the mutation was in at least the 2 outer layers. Furrowed-fruit mutants were the result of unequal cell size and unsymmetrical growth of the flesh. In 2 of 11 such mutants, anthocyanin was not formed in the depressed area, where the outer cells degenerated.
Flowering Date of Onion Bulbs as Affected by Light and Temperature Treatments during Storage1
Authors: DeMille Brent , Vest Grant
Published: August 2022

Onion (Allium cepa L.) bulbs exposed to light during all or a half of a 6-month storage period produced plants that flowered 2 to 4 days earlier than those kept in continuous dark. Bulb storage at 7°C resulted in earlier flowering than did a temperature regime of 2° the first half and 7°C the last half of the storage period.
Content of Thiocyanate Goiterogen in Radishes as Related to Nutrient Concentration and Sulfur Nutrition1
Authors: Bible B. , Chong Calvin
Published: August 2022

Thiocyanate ion (SCN−) content was determined in root and foliage of ‘Burpee White’ and ‘French Breakfast’ radishes (Raphanus sativus L.) grown hydroponically in modified Hoagland’s solution at 2 concentrations (½ × and 2×) and sulfate at 3 levels (1, 4, and 8 meq/liter). Root and foliage of both cultivars grown in ½ × solution contained more SCN− than tissues from plants grown in 2 × solution. Although SCN− content of ‘Burpee White’ roots increased linearly with sulfate level in ½ × solution, SCN− content in corresponding ‘French Breakfast’ roots and in roots of both cultivars grown in 2× solution was not significantly affected by sulfur nutrition. Nutrient concentration altered the synthesis or accumulation of thiocyanate-yielding compounds without affecting growth. Results indicate that the enforcement of regulations governing permissable amounts of toxicants, such as SCN−, in new cultivars may be difficult because of genotype-nutrient interaction which can induce variability in toxicant content.
Citrus Yield and Quality as Affected by Subsurface Irrigation1
Authors: Constantin Roysell J. , Brown Ralph T. , Braud Harry J.
Published: August 2022

Supplemental subsurface irrigation resulted in increased yield and fruit size of ‘Washington’ navel and ‘Owari’ satsuma oranges. The larger fruit size, as a result of irrigation, induced a slight but significant increase in peel thickness. Supplemental moisture resulted in a reduction in juice content of ‘Owari’ satsuma. With ‘Washington’ navels irrigation increased juice content, or was equal to the control, in 4 out of 6 years. Irrigation did not greatly influence pH, percent soluble solids or solids/acid ratio of the juice. Two years results showed that irrigation did not affect peel color of ‘Washington’ navels. In 1973 irrigation had no effect on juice color of both types of oranges.
Rejuvenating Highbush Blueberries1
Authors: Howell Gordon S. , Hansen C. M. , Bittenbender H. C. , Stackhouse S. S.
Published: August 2022

Radical pruning rejuvenated highbush blueberries (Vaccinium australe Small) which had become excessively large and unproductive. The method returned poorly productive bushes (less than 3,390 kg/ha or 1.5 tons/acre) to superior production (11,300 kg/ha or 5 tons/acre) in 2 years. After 4 years, yields were greater yet (18,080 kg/ha or 8 tons/acre).
Abnormalities in Seed Development in Pistacia vera L.1
Authors: Bradley Muriel V. , Crane Julian C.
Published: August 2022

In the pistachio cv. Kerman an average of 26% of the fruits contain no seeds or only poorly developed ones at maturity. A study of aberrations revealed; a) pollen tubes sometimes entered the embryo sacs at the chalazal end (the pistachio is chalazogamous), which may result in eventual degeneration of endosperm or zygote nuclei; b) frequent degeneration of zygote (or egg) or young endosperm nuclei from unknown causes; c) occurrence of a brown spot on the funiculus of many young seeds in some years, the necrosis usually spreading to the embryo sac; d) and hypertrophy of nucellar cells in some older seeds was frequently accompanied by proliferation of other nucellar cells, both limiting development of embryo and endoperm. In cv. Bronte a frequent aberration is protrusion of endosperm or embryo through a greatly distended endostome.
Effect of Short-Term High CO2 Treatment on Storage of ‘d'Anjou’ Pear1
Authors: Wang C. Y. , Mellenthin W. M.
Published: August 2022

Treatment of ‘d'Anjou’ pears (Pyrus communis L.) with high CO2 atmosphere for a short period immediately following harvest prolonged storage life, retarded ethylene production, delayed the climacteric rise in respiration, reduced loss of malic acid, suppressed increase in protein N, retained firmness, quality and the capacity to ripen after long storage. Treatment with 12% CO2 for 2 or 4 weeks provided the best results without injury.
Yield-Tenderness Relationships in ‘Dark Skinned Perfection’ Peas1
Authors: Pumphrey F. V. , Ramig R. E. , Allmaras R. R.
Published: August 2022

Maturity effects on yield of fresh peas (Pisum sativum L.) were identified by yield-tenderometer measurements. A percent yield-tenderometer reading relationship was shown to be a useful means for yield adjustment to a common maturity—100 tenderometer reading. Analysis of random error in the predicted percent yield, as a function of tenderometer reading, indicates the need to plan harvests within the 90 to 110 tenderometer range. Alternatively, the yield-tenderometer reading relationships show the possible magnitude of errors incurred in comparing green pea yields when no adjustment is made for dissimilar tenderometer ratings.
Influence of Sampling Time on Elemental Composition of Strawberry Leaves and Petioles1
Authors: John Matt K. , Daubeny Hugh A. , McElroy Fred D.
Published: August 2022

Concentrations of 13 macro and micro elements in leaves and petioles of 3 strawberry (Fragaria × ananassa Duch.) cultivars were determined biweekly during the growing season. Concentrations of most elements changed rapidly during flowering and fruiting. For most elements, leaf analysis was preferred since markedly greater concentrations occurred in leaves than petioles. These sampling dates and tissue factors, and significant cultivar differences must be considered in interpreting foliar analysis data. Concentrations were relatively stable during the 6 weeks following harvest and this period appeared optimum for sampling.
Carbohydrates in Two Rhododendron Cultivars1
Authors: Wright R. D. , Aung L. H.
Published: August 2022

Determinations of carbohydrates in the plant organs of Rhododendron spp. cv. ‘Sweetheart Supreme’ and ‘Hexe’, were made by chemical analysis, thin-layer chromatography (TLC) and gas-liquid chromatography (GLC). Reducing sugar content was 1.5 times higher in buds than in leaves for ‘Hexe’ with no significant differences for ‘Sweetheart Supreme’. Reducing sugars were also higher in the roots than stems with both cultivars. Sucrose content was 1.4 times greater in leaves than in buds of ‘Hexe’ and 1.6 times greater in ‘Sweetheart Supreme’. Starch was significantly higher in leaves and buds than in stems and roots. The predominant soluble sugars identified by TLC and GLC were sucrose, glucose, and fructose. Small but detectable amounts of raffinose and maltose and an unidentified compound were also found in the plant organs.
An Economic Evaluation of Consumer Characteristics Affecting Sweet Potato Consumption1
Authors: Mathia Gene A.
Published: August 2022

The purpose of this report was to relate several economic and social characteristics of sweet potato consumers to level of fresh sweet potato consumption. National cross-sectional data were used to identify consumption patterns using the least squares regression procedure. Relationships were estimated for white and non-white households.

The relationships for white households indicated that price of sweet potatoes, family income, number of meals eaten-at-home, family size, and expenditures for white potatoes were important determinants of weekly sweet potato consumption. Regional, urbanization, and seasonal differences were also apparent for white households. Education, age, and employment status were not critical in determining consumption patterns.

The relationship for the non-white households was similar structurally to the white household relationship but the sample size was not sufficiently large to yield statistically significant coefficients for some of the variables found important in the white household. Nevertheless, price, age and number of households did exhibit statistically significant coefficient. Seasonal and urbanization differences were noted.

Sweet potato merchants should find the relationships useful in market segmentation. Sales efforts should take into account at least regional, seasonal, and urbanization differences.
Effect of Seed Coating on Performance of Lettuce Seeds in Greenhouse Soil Tests1
Authors: Roos E. E. , Moore F. D.
Published: August 2022

Performance of raw seeds of 2 lettuce, Lactuca sativa L., cultivars was compared with that of seeds from the same lots that had received 7 different seed coatings. Total emergence and coefficient of variability Of plant weights at 20 days were equal for coated and raw seeds in most instances. Coated seeds emerged 1 to 2 days later than raw seed and resulted in lower seedling weights. Seed coatings make possible precision planting of lettuce with apparently no sacrifice in overall performance.
Effect of Washing ‘Hamlin’ Orange on Chlorophyll and Carotenoid Changes During Degreening1
Authors: Jahn Otto L.
Published: August 2022

‘Hamlin’ oranges were washed by hand or with various mechanical-washer procedures. The latter included variations in washing and brushing time and brush-bristle size. Washing procedures had little effect on subsequent chlorophyll loss during degreening. Carotenoid synthesis was significantly reduced by washing before degreening. These reductions in carotenoid levels were not appreciably affected by changes in washing time or brush-bristle size. Hand-washing oranges with a sponge reduced carotenoid synthesis less than mechanical washing. Carotenoid synthesis was reduced by less brushing than was required to clean the fruit, but “over” brushing had little further effect.
Method of Diplandroid Formation and Yield of Progeny from Reciprocal (4x-2x) Crosses1
Authors: Kidane-Mariam Haile-Michael , Peloquin S. J.
Published: August 2022

In 6 families of reciprocal crosses involving 3 tetraploid (2n = 4x = 48) cultivars (‘Wis. 639’, ‘Merrimack’, and ‘Superior’) and 3 diploid (2n = 2x = 24) Phureja-haploid hybrids (W5293.3, W5295.7, and W5845.1), significantly higher tuber yields were obtained in 1970 in families only when the 2x clone W5295.7 was the female parent. The differences in yield in the progeny of these reciprocal crosses were attributed to the mode of 2n gamete formation, since of the 2x clones used, only W5295.7 forms diplandrous gametes by first division restitution. In 1971 with the same materials at 2 locations, significantly higher tuber yields were obtained only in the progeny of 4x × 2x crosses with W5295.7 as the pollen source. These results agree with the hypothesis that the method of diplandroid (2n pollen) formation is responsible for differences in yields of the progeny from reciprocal crosses. Data agreeing with this hypothesis resulted from reciprocal crosses involving four 4x cultivars (‘Kennebec’, ‘Katahdin’, ‘Platte’, and ‘Wis 231’) and two 2x clones (W5295.7 and W5293.3). The progeny from these reciprocal crosses were tested for yield in 1971 and 1972. Differences in yield from progeny of reciprocal crosses again were obtained only with the 2x clone W5295.7 which forms diplandroids by first division restitution.
Cultivar Ratings for Susceptibility and Resistance to The Leaf Roll—Necrosis Disorder of Lilac1
Authors: Walker J. T. , Hibben C. R. , Allison John C.
Published: August 2022

Lilacs (Svringa vulgaris L. and other spp.) at 6 locations in Northeastern United States were evaluated over several years for their sensitivity or resistance to urban-generated pollutants responsible for the leaf roll-necrosis disorder. Twenty-three cultivars were classified as slightly injured, 71 were moderately injured, and 5 were severely injured. S. vulgaris cultivars were more sensitive than non-S. vulgaris and interspecific hybrids.
Regeneration of Whole Plants from Isolated Stem Parenchyma Cells of Solanum sisymbriifolium1
Authors: Fassuliotis George
Published: August 2022

Embryogenic callus was induced when pith of Solanum sisymbriifolium Lam. was cultured on Linsmeier-Skoog (LS) medium supplemented with (6-[(3,3-dimethylallyl) amino]-purine) (2iP), indole-3-acetic acid (IAA), and (2,4-dichlorophenoxy) acetic acid (2,4-D). Combinations of 2iP and IAA were tested for best growth rate of stock callus cultures. Differentiation of leaflets was induced when explants were grown on LS medium with high concentrations of 2iP and low IAA. Roots were formed upon transfer to Nitsch's medium that contained IAA. Morphologic variations in the leaves and cytological studies of callus-induced plants indicated that they were genetically aberrant. Callus-induced plants retained their resistance to the root-knot nematode, Meloidogyne incognita.
Seasonal Changes in Origin and Rate of Development of Root Initials in Douglas-fir Stem Cuttings1
Authors: Bhella H. S. , Roberts A. N.
Published: August 2022

We determined origin and time required for development of callus and root initials in Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stem cuttings from stained sections. Callus originated principally from the vascular cambium, but phloem and xylem parenchyma also contributed. Continuous cell division, elongation, and differentiation within callus gave rise to root primordia. Once formed, root primordia elongated within 15–30 days.

There was no apparent difference in tissue origin of adventitious roots in stem cuttings collected from sheared juvenile or sheared or non-sheared adult trees during pre-, true, and post-dormancy. Time required for callus formation and root initiation varied with degree of bud dormancy. Rooting was low during pre-, almost none during true, and highest during post-dormancy.
Effect of Ethylene on Carnation Growth1
Authors: Piersol John R. , Hanan Joe J.
Published: August 2022

Carnation (Dianthus caryophyllus L) cv Red Sim plants were treated with 100, 300 and 500 ppb C2H4 for varying durations at different growth stages. Carnations treated during rapid elongation (Stage III) were more susceptible to C2H4 than were plants treated at stages of less rapid growth (Stages I and IV). An effective dosage term (ppb-days) was used to correlate C2H4 concentration and exposure length. Although the highest dosages produced the greatest growth reduction, the rate of inhibition was higher at low dosages commonly found in metropolitan areas.
Comparison of Instrumental Methods for Measuring Ripening Changes of Intact Tomato Fruit1
Authors: Jahn Otto L.
Published: August 2022

Instrumental methods evaluated for effectiveness in following color changes in ripening tomato fruit (Lxcopersicon esculentum Mill.) included a light-reflectance and 2 light-transmittance sample systems. Each system was tested with wavelength pairs of 500–595, 540–595, and 595–650 nm. Instrument methods, with appropriate photomultipliers, generally were more sensitive to color changes than were visual observations. The light-transmittance systems were also more sensitive to small changes than the light-reflectance system. However, with all systems, measurements at 595 650 nm were highly correlated with visual color ratings during ripening. Light-transmittance measurements at 540–595 nm were effective in detecting changes at an earlier ripening stage than either reflective or visual observations. Because of complex pigment changes, this measurement increased rapidly during initial ripening stages, and then decreased during later stages, making it more difficult to relate to visual color.
Artificial Lighting and Spacing as Photosynthetic and Yield Factors in Winter Greenhouse Tomato Culture1
Authors: Rodriguez B. P. , Lambeth V. N.
Published: August 2022

Photosynthetic and yield responses of tomato, Lycopersicon esculentum L., ev. Tuckcross V and Tuckcross 533 supplemental lighting and spacing were studied during the unusually dark winter of 1972–73. Supplemental lighting and wide spacing increased total flowers, % fruit set, fruit size, and total fruits/plant. and contributed to greater early and total fruit yields. The increases were related to increased apparent photosynthetic rate and efficiency. Supplementary top lighting (184 W/m2) increased fruit weight/plant 1107 g/plant (89%) over natural lighting for an increase of 6.0 g/plant for each watt/m2. Supplementary top + side lighting (368 W/m2) increased fruit weight 2853 g/plant (121%), an increase of 7.7 g/plant for each watt/m2.

Maximum fruit yield/plant was obtained with top + side lighting at a spacing of 50.8 × 41 cm in a staggered double row bed. Plant spacing of 38.1 × 41 cm with maximum lighting gave greatest yield/unit area. Photosaturation was not attained bv supplementary lighting.
Chemical Regulation of Sex Expression in a Gynomonoecious Line of Muskmelon1
Authors: Loy J. Brent , Natti Thomas A. , Zack Cheryl D. , Fritts Susan K.
Published: August 2022

Applications of (2-chlorothyl)phosphonic acid (ethephon) at 240 ppm in the greenhouse and at 480 ppm in the field extended the pistillate flowering stage of a gynomonoecious line of muskmelon (Cucumis melo L.). Foliar application of the aminoethoxy analog of rhizobitoxine, aminoethoxyvinyl glycine (AVG), enhanced staminate and/or perfect flower formation in the gynomonoecious line. The results support the feasibility of using gynomonoecious parents for producing hybrid muskmelons without hand pollinations.
Accumulation of Sodium and Chloride in Leaves of Sprinkler-irrigated Grapes1
Authors: Francois L. E. , Clark R. A.
Published: August 2022

Three grape cultivars (Vitis vinifera L.) were sprinkler-irrigated to determine if they would absorb sufficient sodium and chloride through their leaves to attain toxic levels. The concentration of both Na and Ca within the leaves increased linearly with sprinkling time. Both ions were approaching known tolerance levels after 54 hours of sprinkling. The counter ion of the 3 salt species tested (NaCl, CaCl2, and Na2SO4) had no effect on the amount of sodium or chloride accumulated.
The Mung Bean Rooting Bioassay: A Re-examination1
Authors: Blazich Frank A. , Heuser Charles W.
Published: August 2022

Inconsistent results obtained with the mung bean (Phaseolus aureus Roxb.) rooting bioassay led to a reexamination of procedures. Autoclaving the double distilled water used completely eliminated the inconsistent results, but boiling and filter sterilization were not completely satisfactory. A decrease in rooting of both control and auxin-treated cuttings was noted in seedlings older than 10 and 9 days respectively. Adventitious roots were initiated within 5 days; incubation for 2 additional days did not increase rooting response. Increasing irradiance from 380 to 4080 μW/cm2 decreased rooting of both control and auxin treated cuttings.
Postharvest Wound Healing in Citrus Fruit: Induction of Phenylalanine Ammonia-lyase in Injured ‘Valencia’ Orange Flavedo 1
Authors: Ismail M. A. , Brown G. E.
Published: August 2022

Healing of minor injuries to ‘Valencia’ orange (Citrus sinensis (L) osbeck) occurs rapidly at 30°C and 96-98% relative humidity. It is manifested by a marked increase in the activity of phenylalanine ammonia-lyase (PAL) and deposition of lignin. PAL activity is confined mainly to injured flavedo while uninjured peel and albedo tissues exhibit very little activity. Inoculation of injured flavedo, immediately after injury, with P. digitatum sacc. disrupts the increase in PAL activity. When acetone powder from decayed peel was mixed with that of healed injured fruit and enzyme preparation was made from the mixture, there was no apparent reduction in phenylalanine ammonia-lyase activity, except that cuased by dilution. The synthesis of both PAL and lignin in mature fruit is strongly inhibited by cycloheximide, but not by actinomycin D.
Tolerance of 5 Warm-season Turfgrasses and 36 Ornamental Plant Species to Asulam 1
Authors: Neel P. L. , Burt E. O. , Carlyle S. L.
Published: August 2022

Methyl sulfanilylcarbamate (asulam) was effective for the selective control of several grassy weeds in established st. augustinegrass (Stenotaphrum secundatum (Walt.) Kuntze), ‘Tifway’ bermudagrass (Cynodon dactylon L.), and ‘Emerald’ zoysiagrass (Zoysia matrella Merr.). Bahiagrass (Paspalum notatum Flugge) and centipedegrass (Eremochloa ophuroides (Munro) Hack.) were severely injured when asulam was used at a rate of 2.24 kg ai/ha. Thirty-six species of ornamental plants were relatively tolerant to foliage applications of asulam at rates of 2.24 and 4.48 kg ai/ha with growth normal on all but 4 ornamental species 22 weeks following treatment.
Pest Control and Phytotoxicity on Indoor Ornamental Plants with Dichlorvos Fumigation 1
Authors: Hamlen R. A. , Henley R. W.
Published: August 2022

A 20% dichlorvos impregnated polyvinyl chloride (PVC) resin strip (6.3 × 15.9 × 0.7 cm) per 28.3 m3 interior room significantly reduced the number of mealybugs (Phenacoccus solani Ferris) 48 hour posttreatment. Greenpeach aphid (Myzus persicae Sulzer) and twospotted spider mite (Tegranychus urticae Koch) populations were not suppressed. Exposure of pests to a stake label with an attached dichlorvos impregnated PVC strip produced the same effects as the room fumigation test. Placement of a 20% dichlorvos PVC resin strip per 25.4 × 70 cm polyethylene bag with infested plant material for 12 or 24 hr reduced populations of M. persicae, P. solani and T. urticae, however, 3 exposures at 7-day intervals were more effective in maintaining low populations. Fumigation in bags produced phytotoxic effects with specific plants.
Measurement and Variation of Sugar Concentration of Pickling Cucumbers
Authors: McCreight J. D. , Lower R. L. , Pharr D. M.
Published: August 2022

In the paper, Measurement and Variation of Sugar Concentration of Pickling Cucumbers by J. D. McCreight, R. L. Lower, and D. M. Pharr (J. Amer. Soc. Hort. Sci. 103(2):145-147. 1978), the first sentence of the introduction should read “Bloating of commercially brined cucumbers results in a 5 million dollar loss each year to the U.S. pickle industry (6).”
Selected Leaf Wax Alkanes in Chemotaxonomy of Citrus1
Authors: Nordby Harold E. , Nagy Steven , Smoot John M.
Published: August 2022

Long-chain alkanes present in epicuticular wax of citrus leaves changed in composition as the leaves matured. From 89 to 95% of the hydrocarbons in the mature leaves were linear, saturated, and C29 to C33 compounds. Alkane profiles changed during the year but were not influenced by the period of leaf flush (spring or fall). The alkane profiles for 67 citrus cultivars, representing 11 citrus biotypes, were determined by gas liquid chromatography (GLC). The mean alkane profile of 9 of the bio types were distinct from the others as determined by Duncan's multiple range test, Twelve other citrus and related taxa were examined, and the profile of each showed possible inheritance patterns.
Observation of a Low Temperature Effect on Roses1
Authors: Hanan Joe J.
Published: August 2022

Rosa hybrida L. cvs. Forever Yours and Cara Mia, were subjected to split night temperatures from November 1, 1977 to February 8-18, 1978. During the 22 weeks of treatment, split temperatures seriously delayed production and markedly reduced quality. Split temperatures for roses as a means of energy conservation did not appear to be a viable practice. Following the experiment, however, for a 9 week period, after returning night temperatures to 16.7°C, plants in the lowest temperature treatment produced twice as many flowers as compared to the entire previous record with a significant increase in quality and marked increase in bottom shoots. The effect appeared to be cumulative and suggested an inexpensive means for rejuvenating old rose plants.
Endogenous Plant Growth Substances in Developing Fruit of Prunus cerasus L. VI. Cytokinins in Relation to Initial Fruit Development1
Authors: Hopping Murray E. , Young Harry , Bukovac Martin J.
Published: August 2022

Ethanolic extracts of sour cherry (Prunus cerasus L. cv. Montmorency) fruit were partitioned into butanol and water-soluble fractions. Following paper chromatography, each fraction was tested for cytokinin activity by the radish cotyledon and soybean callus bioassays. Activity in both fractions increased between 14 and 21 days after anthesis, and remained high at 28 days, although cell division in the pericarp had ceased. One growth promotor in the butanol fraction resembled zeatin in its chromatographic mobility on both paper and Sephadex LH-20, and was identified as zeatin by gas chromatography-mass spectrometry of its trimethylated derivative. A water-soluble growth promoter, which exhibited activity in only the radish cotyledon bioassay, was unaffected either by acid or by alkaline phosphatase hydrolysis.
Seasonal Changes in Stomatal Response to Leaf Water Potential in Apple1
Authors: Lakso Alan N.
Published: August 2022

The relationship between stomatal conductance and leaf water potential in field-grown apple trees (Malus domestica Borkh.) was determined throughout one growing season. Between May and September the leaf water potential required to close stomates decreased (became more negative) by about 25 bars, indicating decreasing sensitivity of the stomates to leaf water stress. A good linear correlation was found between stomatal conductance and net photosynthesis in trees grown under a wide range of water stress conditions. In September net photosynthesis of excised leaves of field trees was not reduced to zero until leaf water potentials reached −50 to −60 bars. The results emphasize the importance of pre-conditioning and time of season in plant water relations studies.
Asexual Embryogenesis in Theobroma cacao L.1
Authors: Pence Valerie Creaser , Hasegawa Paul M. , Janick Jules
Published: August 2022

Cultured immature sexual embryos of Theobroma cacao proliferated asexual embryos, but embryogenesis was not observed from leaf, pericarp, or ovule tissues. Cotyledons from immature, unpigmented embryos (2.5 to 10 mm long) were highly embryognie, while larger more mature, pigmented cotyledons initiated roots as their only form of organized development. Embryogenesis occurred in light and darkness when a basal medium was supplemented with coconut water and 1.5 mg/liter NAA. Proliferated embryos recultured in a liquid medium continued development.
Siberian C Rootstock Delays Bloom of Peach 1
Authors: Young Eric , Brenda Olcott-Reid
Published: August 2022

Siberian C seedling rootstock delayed the bloom of 3 cultivars of peach (Prunus persica (L.) Batsch) as compared to seedling rootstocks Harrow Blood, Lovell, and Halford. Starting about 1 month before bloom, trees on Siberian C developed more slowly than those on other rootstocks as measured by flower bud moisture content. Bloom was delayed 5 days by Siberian C in both 1977 and 1978, with no adverse side effects.
Pecan Yield, Quality, Nutlet Set, and Spring Growth as a Response to Time of Fall Defoliation 1
Authors: Worley Ray E.
Published: August 2022

Defoliation of pecan trees [Carya illinoensis (Wang) K. Koch] prior to October 1 prevented nutlet formation the next year in 2 out of 3 years. September defoliation was most damaging to yield, October defoliation was less damaging, and defoliation on November 1 did not reduce yield. Early defoliation delayed bud break the next year and August defoliation reduced nut size. Percentage kernel was reduced when defoliation date moved from August 1 to September 15.