bluuebunny/crossref_metadata_2025 huggingface dataset:
Fate of 15N-Labeled Urea Applied to Mature Highbush Blueberries
Authors: Retamales Jorge B. , Hanson Eric J.
Published: August 2022

To study the efficiency of fertilizer use by highbush blueberry (Vaccinium corymbosum L.), four mature ‘Bluecrop’ plants were treated before budbreak (21 Apr.) with soil applications of 15N-enriched urea at a rate equivalent to 40 kg N/ha. Leaf samples were collected at 1- to 4-week intervals during the season and whole plants were harvested at the end of the growing season (22 Sept.). Different plant components were separated, dried, weighed, and analyzed by mass spectrometry. Fertilizer-derived N was observed in leaves 2 weeks after application. The percentage of N from the fertilizer peaked 3 weeks after application (16.5%) and declined to ≈11% shortly thereafter. Plants recovered 32% of applied N by the end of the growing season. Leaves accounted for 32% of this total. Shoot tissue also accounted for 32% of fertilizer-derived N in the plant, with the highest percentage accumulating in young shoots. Less than 15% of fertilizer N remained in the soil at the end of the season.
Postharvest Calcium Chloride Infiltration Affects Textural Attributes of Apples
Authors: Abbott Judith A. , Conway William S. , Sams Carl E.
Published: August 2022

‘Golden Delicious’ apples (Malus domestica Borkh.) were pressure-infiltrated (68.9 kPa) at two harvest dates with 0%, 1%, 2%, or 4% (w/v) solutions of CaCl2 and stored at 0C for 2, 4, or 6 months followed by 1 week at 20C. Calcium concentrations, axial compression profiles, and Magness-Taylor firmness were measured. Calcium chloride infiltration increased all measures of tissue strength immediately and relative increases persisted during storage. A 1-week difference in harvest date markedly affected Ca uptake and textural responses; however, for both dates, 2% CaCl2 was effective in firming the apples. Apples from the second harvest, which were treated with 2% CaCl2 and stored for 6 months, had textural measurement values equal to or greater than those of comparable apples infiltrated only with water and measured before storage. Calcium chloride at 4% had a greater firming effect, but caused severe surface damage. Differential reponses to CaCl2 levels and storage durations by various textural measurements indicate that supplemental Ca not only increased firmness retention during storage, but also induced patterns of textural change different from those that occurred under the influence of the endogenous Ca alone.
Ultrastructural Changes Associated with Chilling Injury in Mature-green Tomato Fruit
Authors: Marangoni Alejandro G. , Smith Alexandra K. , Yada Rickey Y. , Stanley David W.
Published: August 2022

The effect of low temperature on cell ultrastructure was investigated in chilling-sensitive and chilling-resistant tomato fruit (Lycopersicon esculentum Mill.) Damage to the chilling-sensitive cultivar included microvesiculation of the endoplasmic reticulum and loss of ribosomes, chloroplast, and mitochondrial swelling; loss of starch granules; disorganization of the internal lamellae of chloroplasts; grana unstacking, as well as plastoglobuli and tonoplast degradation. Only a slight disorganization of the internal chloroplast lamellae was evident in the resistant species after 7 days at 5C. The primary site of damage appeared to be the chloroplast in both chilling-sensitive and -resistant species. The ultrastructural damage observed could be explained in terms of membrane disruption.
Quality of Tropical Sweet Potatoes Exposed to Controlled-atmosphere Treatments for Postharvest Insect Control
Authors: Delate Kathleen M. , Brecht Jeffrey K.
Published: August 2022

Sweet potatoes (Ipomoea batatas L.) were exposed to low O2 and high CO2 for 1 week during curing or subsequent storage to evaluate the use of controlled atmospheres (CA) as insecticidal treatments for sweet potatoes infested with sweet potato weevil (Cylas formicarius elegantulus). Sweet potato roots tolerated 8% O2 during curing, but, when exposed to 2% or 4% O2 or to 60% CO2 plus 21% or 8% O2, they were unsalable within 1 week after curing, mainly due to decay. Exposure of cured sweet potatoes to 2% or 4% O2 plus 40% CO2 or 4% O2 plus 60% CO2 for 1 week at 25C had little effect on postharvest quality. However, exposure to 2% O2 plus 60% CO2 resulted in increased decay, less sweet potato flavor, and more off-flavor. These results indicate that exposure of sweet potatoes to O2 and CO2 levels required for insect control is not feasible during curing, but that cured sweet potatoes are capable of tolerating CA treatments that have potential as quarantine procedures.
The Pillar Peach Tree and Growth Habit Analysis of Compact × Pillar Progeny
Authors: Scorza Ralph , Lightner G.W. , Liverani A.
Published: August 2022

Branch growth of compact (CT) and “Pillar” (PI) peach [Prunus persica (L.) Batsch.], a columnar growth type, and progeny of CT × PI was analyzed. PI trees were distinguished from CT trees by narrower branch angles and relatively fewer and longer branches. CT × PI hybridization produced two distinct classes of trees in a 1:1 ratio—globe shape (GL) and upright (UP). GL trees had a large number of branches, resembling CT trees, but had narrower branch angles. UP trees resembled PI trees, but with wider branch angles. Analysis of seedling growth at 1, 2, and 3 months indicated that height and number of lateral branches could be used to classify UP and GL mature tree form. Branch angle measured at 2 months was important in distinguishing GL from CT seedlings. Such measurements on young seedlings may be used for early selection of growth habit. The reported results indicate that peach tree form, in respect to branching density and branch angle, can be readily manipulated through hybridization of the appropriate growth types. The columnar form of the PI tree suggests its potential for high-density production systems and its use as a parent in developing narrow canopied trees.
Inheritance of Root Color and Carotenoid Synthesis in Carrot, Daucus carota, L.: Orange vs. Red1
Authors: Nakdimon Umiel , Gabelman W. H.
Published: August 2022

The genetic control of root color and carotenoid synthesis in carrot, Daucus carota L., was studied using 3 carrot cultivars, Kintoki Heian Nagabuto, KHN: Kintoki Osaka, KOS: Kintoki Davis, KDA, and 1 inbred line (W93). Genetic models describing the inheritance of red roots in the F2 were tested in backcross and F3 progenies. In Kintoki cultivars the major pigment is lycopene; beta-carotene is present in smaller amounts; zeta-carotene, gamma-carotene and phytofluene were also detected. In W93 the main pigments are beta-carotene and alpha-carotene; zeta-carotene, gamma-carotene and phytofluene also are detected. The pigments were separated into carotene and carotenol fractions by partition column chromatography. The pigments in the carotene fraction were studied qualitatively and quantitatively by thin layer chromatography. Orange (W93) was dominant to red (KHN, KOS, KDA) in the F1 progeny. The F2 segregation indicated that at least 2 genes are responsible for the differences between orange and red. The segregation of F3, backcrosses, and other progenies revealed the existence of dominant red as well as dominant orange, supporting the digenic composition of F2 populations and indicating the locus with the dominant orange allele to be epistatic to the locus with the dominant red allele. The homozygous recessive would be orange also. The analysis of progenies from the crosses W93 × ‘Kintoki’ suggested a dominant gene for accumulation of alpha-carotene in W93 and a dominant gene for the accumulation of lycopene in ‘Kintoki’.
Effect of Gibberellins and 6-Benzyladenine on the Shape and Fruit Set of ‘Delicious’ Apples1
Authors: Stembridge G. E. , Morrell G.
Published: August 2022

The cytokinin 6-benzyladenine (BA) and gibberellins A4 + A7 (GA4+7), but not GA3, increased the fruit length-diam (L/D) ratio of ‘Delicious’ apples. Prominence of the points near the fruit calyx was increased more by BA than by GA4+7, but increased most when the 2 were combined. Sprays during bloom were more effective than either postbloom or prebloom sprays.

A bloom spray combining GA4+7 and BA at 100 ppm each decreased fruit set of open pollinated flowers in one year, but not in another. Concentration of 50 ppm or less altered fruit shape without any significant effect on the number of seed, fruit set, firmness, or fruit size.
Snapdragon Stem Tip Breakage as Related to Stem Lignification and Flower Color1
Authors: Adams David G. , Urdahl Wesley A.
Published: August 2022

Breakage in the floret area of the stem which occurs during harvesting or post-harvest handling in commercially mature snapdragons was investigated. The point of breakage was not influenced by the number of open florets on the stem, provided many unopened buds remain at the apex. Breaking occurred lower on the stem in crops harvested during fall as opposed to summer months. The break point appears to be related to the end of the concentric column of safranin stainable, lignified xylem. Although not without exception, breakage also appears related to flower pigmentation in that anthocyanin (red) containing cultivars tend to break high whereas aurone (yellow) containing cultivars break low in the floret area. These factors suggest a competition for phenyl propanoid precursors which are consumed in both lignification and pigmentation.
Comparative Anatomy of Pericarps of Four Tomato Mutants1
Authors: Chu Mel Chih-Yu , Thompson A. E.
Published: August 2022

Pericarps of 4 tomato mutants and 1 cultivar were compared anatomically. Sticky peel (pe) had very little cuticle on its epidermal surface and was devoid of hypodermal cells. Peach (p) possessed a heavily cutinized and rough surface over the epidermis with a hypodermal layer comparable to that of the standard cv. Campbell 146. Easy peeling (ep) was more heavily cutinized than Campbell 146, but the hypodermal layer was comparable in structure. The easy peeling characteristic appeared to be associated with more intercellular space among and disintegration of the fully mature parenchyma cells below the hypodermis. Oblong fruits (obl) have a strong skin resulting from a thick hypodermal layer. They also possess a heavily cutinized epidermis and relatively compact, small inner parenchyma cells.
Response of Azaleas to Precisely Controlled Temperatures1
Authors: Larson Roy A. , Biamonte Richard L.
Published: August 2022

Vegetative growth, flower bud initiation, and early flower development of ‘Red American Beauty’ azaleas were enhanced at temp of 30-26°, 26-22°, 30-22°, 26-18°, and 22-18°C. Earliest flowering occurred following temp of 22-18°, 22-14°, and 18-14°C. The 4°C difference between day and night temp resulted in plants superior in quality to those exposed to an 8° difference.
Influence of Detachment from the Tree on the Respiration of Apples1,2
Authors: Smock R. M.
Published: August 2022

Fruit detachment and small branch removal before fruit harvest stimulated the rise in the climacteric. Defoliation and removal of the phloem from the fruit pedicels stimulated the rise in only about one-half of the experiments. IAA sprays gave erratic results, with an increase in the time of the respiratory rise in about half of the cases. Sprays of GA had no effect. Fruit dipping after harvest in IAA, GA, ABA, and trachael sap had no effect on subsequent respiration.
Culture of Apple Shoots from Buds in Vitro1,2
Authors: Dutcher Roger D. , Powell Loyd E.
Published: August 2022

Axillary buds from apple shoots when cultured aseptically in vitro readily develop into new shoots. A nutrient medium is used consisting of sucrose and macro and micro elements. Buds grown in stationary culture develop into shoots with small leaves and short internodes. The miniature condition appears to be due to inability of the rootless explants to absorb sufficient nutrients. When buds are cultured in rotating culture where the developing leaves are bathed in nutrient solution, shoots of near normal size and appearance are produced. Light is essential for growth. Low concn of abscisic acid prevents growth of the buds.
Correlation Among Growth, Yield, and Nutritional Factors for Pecan (Carya illinoesis W. cv. Stuart): Correlations with Yield, Quality, and Terminal Shoot Growth1
Authors: Worley Ray E. , Harmon S. A. , Carter Robert L.
Published: August 2022

Correlations between pecan yield, quality, tree growth, and various nutritional variables were studied over an 8-year period. Yield was negatively correlated with yield the previous year, but yield was positively correlated with yield accumulated over several years. Terminal shoot growth and nuts/lb. varied in a pattern similar to yield. Soil and leaf analysis was not often correlated with yield, nut quality, or tree growth. Degree of leaf retention in a heavy crop year was positively correlated with yield the following season.
Histochemical Study of Xylem Blockage in Cut Roses1
Authors: Parups E. V. , Molnar J. M.
Published: August 2022

Unfixed sections of fresh, or 5-day-old, xylem plugged rose stems were examined histochemically. There was evidence that the material blocking xylem vessels of senescing rose stems contained carbohydrates, pectin-, lipid-, and protein-like compounds and some enzymes. Tannins, lignin, and callose were not encountered in the blocked vessels.
Ethephon for Postharvest Degreening of Oranges and Grapefruit1
Authors: Grierson W. , Ismail Fawzeya H. , Oberbacher M. F.
Published: August 2022

Ethephon [Ethrel, (2-chloroethyl) phosphonic acid, 2-CEPA] was tested on ‘Hamlin’ oranges in 2 seasons and on ‘Valencia’ oranges and ‘Marsh’ grapefruit in 1. In 1 picking, very green oranges, mature enough to degreen with gaseous ethylene (C2H4), failed to degreen with ethephon. Once mature enough to respond to ethephon, rate of chlorophyll disappearance was comparable to C2H4 degreening. Waxing sharply arrested color change due to C2H4 degreening, but had comparatively little effect on ethephon-dipped fruit. Stem feeding was effective but impractical. Little correlation was found between degreening rate and: ethephon concn (from 1,000 to 12,000 ppm); immersion time (from 1 to 10 min); or use of vacuum vs. atmospheric pressure during immersion. Duration of color change was sometimes sharply curtailed after brief immersion periods or low ethephon concn. Internal C2H4 levels increased from 0 prior to ethephon treatment to 5-16 ppm 24 hr after, with emanation rates from the fruit of 1 to 6 µl/Kg/hr. It is theorized that a threshold concn is necessary for degreening with no indication of stimulation of autogenous C2H4 production.
Isolation of Three Lipid Root-Initiating Substances from Juvenile Hedera helix Shoot Tissue1
Authors: Heuser Charles W. , Hess Charles E.
Published: August 2022

Three lipid-like root-promoting compounds were isolated from the easy-to-root juvenile form of English ivy, Hedera helix L. The purification procedure involves extracting with methanol-chloroform and chromatography on columns of charcoal-celite, silica gel and LH-20 Sephadex. Ultraviolet and infrared spectroscopic studies suggest the presence of alcohol and nitrile functional groups. The 3 compounds are unstable and the instability is greatest when the substances are purified. In the purified state, the lipid-like compounds are colorless but become orange-yellow after breakdown. A loss of root-promoting activity occurs with the color change.
Fruit Size Increase in Tomato Following Application of Gibberellic Acid1
Authors: Sawhney V. K. , Greyson R. I.
Published: August 2022

Application of gibberellic acid (GA3) to nonflowering plants of tomato induced multilocular, multicarpellary ovaries. These multilocular ovaries, which were larger at anthesis than nontreated controls, upon pollination produced fruits which were significantly larger both in size and in fresh wt. At least 50% increase in both size and wt was noted in 2 cultivars.
Effect of Intrastylar Pollination Methods on Seed Set of Lilium X ‘Mid-Century’ Hybrid Lilies1
Authors: Cheng Isabell Hsu , Mattson Richard H.
Published: August 2022

A complete 4 × 4 diallel showed significant self-incompatibility and reciprocal differences in L. × ‘Mid-Century’ hybrid lily crosses. For all crosses, normal stigmatic pollination produced more seed set than did either intrastylar pollination method. For selfed flowers, intrastylar pollination methods generally resulted in more seed set but this was statistically nonsignificant. Significant reciprocal differences were found among crosses of ‘Harmony’, ‘Cinnabar’, and ‘Enchantment’ no reciprocal differences existed among ‘Joan Evans’ crosses. Seed set was highly correlated with pod width, length, and days to maturity.
Differentiation of Citrus Stem In vitro1
Authors: Grinblat Uri
Published: August 2022

Concentrations of 10 mg/1 benzyl adenine (BA), 0.1 mg/1 naphthaleneacetic acid (NAA) and 500 mg/1 malt extract, caused maximum initiation of buds from citrus stem explants grown in vitro. Minimum bud initiation occurred in explants grown on basal medium supplemented with 0.1 mg/1 BA, 0.1 mg/1 NAA and 500 mg/1 malt extract (ME).

Roots were initiated in explants grown on basal medium supplemented with 0.1 mg/1 NAA and 500 mg/1 ME, and in medium lacking growth regulators. Plants were produced from these seedling stem explants.
The Relationship of Exotherms to Cold Injury in Apple Stem Tissues1,2
Authors: Quamme H. , Stushnoff C. , Weiser C. J.
Published: August 2022

During controlled freezing as many as 4 exotherms were detected in apple twigs by differential thermal analysis (DTA). Three of the exotherms usually occurred at relatively high temperatures above the killing point of stem tissues. There was no apparent association between any of these exotherms and freezing injury to cambium, cortex, phloem, or vegetative buds. The temp of the fourth exotherm (D), however, coincided with the killing temp of xylem ray and pith parenchyma as hardiness changed during the season. DTA studies and hardiness tests performed on whole and dissected twigs indicated that the fourth exotherm arose from the xylem and pith tissues; that injury to xylem and pith occurred when twigs were frozen below the initiation temp of the fourth exotherm independent of cooling rate and that bud and bark tissues were considerably hardier than xylem in mid-winter while in early autumn and late spring xylem and pith were hardier than buds and bark.

The results suggest that freezing injury to xylem and pith cells is caused by a specific freezing event, and that it is different from freezing injury to other stem tissues. Measurements of the fourth exotherm may provide a convenient way of studying freezing injury and resistance in xylem – a recurring problem in many fruit species.
A Genetic Study of Tolerance in Pea (Pisum sativum L.) to Aphanomyces Root Rot1
Authors: Marx G. A. , Schroeder W. T. , Provvidenti R. , Mishanec W.
Published: August 2022

The genetic basis for tolerance to Aphanomyces root rot found in a selection of P.I. 175227 was studied in a greenhouse tank test. Parental, F1, BC, F2, and F3 populations were screened by subjecting the seedlings to a pure culture of the pathogen.

The results showed that tolerance was associated with dominant, “wild-type”, alleles at 3 unlinked marker loci (Le, A, Pl) and that substitution of the recessive, horticulturally desirable, allele at each of these loci led to a decrease in tolerance. The demonstrated associations were ascribed to genetic linkage rather than to pleiotropy.
Effects of Rootstock on Leaf Element Content of ‘Italian’ Prune (Prunus domestica L.)1
Authors: Chaplin M. H. , Westwood M. N. , Roberts A. N.
Published: August 2022

Plantings of the ‘Italian’ prune (P. domestica L.) were established on seedling peach (P. persica L. Batsch) and clonal Myrobalan 29-C, B, 2-7 (P. cerasifera, Ehrh.); Marianna 4001, 2623, 2624 (P. cerasifera × Munsoniana?, Wight and Hedr.); and St. Julien A (P. insititia L. Bullace) rootstocks in 7 orchard sites in Oregon. Leaf samples were collected in the years 1968 to 1970 and analyzed for element content. Trees with plum rootstocks had greater leaf N, K, Mn, and Zn and slightly less B and Mg than those on peach. Plum clones, Myrobalan 29-C, Myrobalan B, and St. Julien A, were more efficient in the uptake of Ca. There were positive correlations between N and Ca, N and Mg, N and B, N and Zn, Ca and Mg, Ca and B, and Mg and B for most of the stocks. There was a negative correlation between K and Mg for Myrobalan 2-7 and the 3 Marianna clones. Myrobalan B and Marianna 2623 and 2624 had a negative corrleation for K and Ca whereas St. Julien A had a positive correlation.
Effect of the Early Environment on Flowering in Pepper (Capsicum annuum L.)1
Authors: Rylski Irena
Published: August 2022

Air and soil temp have a great influence on the development and flowering of the pepper plant. The time interval between emergence and flowering increases as temp drop. Plants which grew under low temp in any particular growth stage developed an equal or greater number of leaves before the first flower than did plants growing under high temp, regardless of day length.

A soil temp of 10°C retarded plant development, whereas 17°C allowed normal development. The rate of growth increased as soil temp rose. The total plant wt after 100 days of growth under various soil temp increased with rising temp. The top continued to develop with rising temp, but root development was retarded at a soil temp of 30°C or above.
Peach Seed Dormancy in Relation to Endogenous Inhibitors and Applied Growth Substances1
Authors: Diaz Daniel H. , Martin George C.
Published: August 2022

An inhibitor was present in both seed coat and embryo of a high and a low chilling cv. of unstratified peach seeds and its concn decreased as stratification proceeded, Embryonic tissue retained more of the inhibitor than the seed coat. As the concn of inhibitor decreased, seed germination increased. The inhibitor was tentatively identified as abscisic acid (ABA) by chromatography. A bound inhibitor was also present in the seed parts of both cvs., and its concn increased in the embryo as stratification proceeded. More ABA and bound inhibitor were present in the high-chilling cv. than in the low-chilling counterpart, indicating that they may be related as factors which cause a cv. to require long periods of chilling. Application of ABA reduced germination percentage on stratified seeds without seed coats. Application of gibberellic acid (GA) and N-benzyladenine (BA) combined had a synergistic effect in promoting germination of dormant seeds.
Nitrate Accumulation in Spinach Grown at Different Temperatures1
Authors: Cantliffe Daniel J.
Published: August 2022

Nitrate accumulated in spinach plants that did not receive additional fertilizer N when temp was increased above 15°C. When 50 mg N/kg soil was added the NO3 concn increased above 10°C and with 200 mg N/kg soil NO3 increased with temp increments above 5°C. When N fertilizer was added the NO3 concn decreased with a subsequent increment in temp from 25°C to 30°C. The effect of N fertilizer on NO3 accumulation became more apparent with each 5°C rise in temp to 25°C. Either N fertilizer or a temp rise from 5°C to 25°C led to a significant increase in the total N concn of the plants. Changes in total N were correlated with changes in NO3-N when N fertilizer was added to the soil or when the temp was changed. Nitrite did not accumulate appreciably at any of 6 temp or 3 N fertilizer levels used.
Effect of Postharvest Calcium Treatments on Internal Breakdown and Respiration of Apple Fruits1
Authors: Bangerth F. , Dilley D. R. , Dewey D. H.
Published: August 2022

Dipping ‘Jonathan’ apples in CaCl2 solution prior to storage greatly reduced the development of internal breakdown (IB) and retarded flesh softening during 19 weeks at 2.2°C plus 1 week at 23°C. Infiltration of fruit with sorbitol produced IB symptoms, whereas glucose caused a dissimilar browning coloration and sucrose yielded no visible damage. Infused Ca inhibited IB symptoms and browning, retarded respiration, reduced the metabolism of endogenous substrates, and increased the oxidation of exogenous substrates. The results suggest Ca inhibits IB by enhancing the uptake and compartmentation of substrates, particularly sorbitol.
Effect of Ethephon-Induced Ethylene on Abscission of Leaves and Fruits of Peaches1
Authors: Daniell Jeff W. , Wilkinson R. E.
Published: August 2022

Mature peach trees (Prunus persica (L.) Batsch. cv. Southland) were treated with 0, 1.73, 2.42, and 3.11 Mmoles/1 of (2-chlorethyl)phosphonic acid (ethephon) and ethylene evolution was measured up to 9 days after treatment. Ethephon caused a marked increase in ethylene evolution, a sharp decrease in the breaking force of fruit abscission, and a pronounced increase in leaf abscission. Ethylene evolution was higher in leaves than fruits. In general, ethylene from tissue explants containing the abscission zone of fruits was higher than that of explants from the side of fruits from treated trees. However, it was postulated that ethylene has an overall affect on all tissue with subsequent abscission rather than a direct effect on the abscission zone of leaves and fruits of peaches.
Effect of Light on Growth of Sweet Cherry (Prunus avium L.) Fruits1
Authors: Ryugo Kay , Intrieri Cesare
Published: August 2022

Sweet cherry fruits covered with aluminum foil bags at the beginning of pit hardening were visibly larger than those exposed to light when examined 14 days later. With ‘Bing’ fruits this difference in size remained nearly constant until harvest while with ‘Royal Ann’ it continued to diverge during “final swell.” The size of covered fruits was larger at harvest, but soluble solids content was much less than in exposed fruits. The alcohol insoluble substances (AIS) of control mesocarp tissue of ‘Bing’ decreased from 15 to 7% during the 2 weeks prior to harvest; those of dark-grown fruits decreased from 13 to 10%. The trends for the ‘Royal Ann’ fruits were similar. About 45% of the AIS was hydrolyzable with pectinase. Comparisons of levels of gibberellins, auxin-like and ABA-like substances between covered and exposed fruits showed neither consistent trends nor differences correlative to size increase during 3 weeks before harvest wherein the possible roles of these hormones could be ascribed. Humidity and ambient temp were not effective factors compared to light in this growth phenomenon.
Reduction of Ozone Damage to Petunia hybrida Vilm. by Use of Growth Regulating Chemicals and Tolerant Cultivars1
Authors: Cathey Henry M. , Heggestad Howard E.
Published: August 2022

Sixty-five cvs. of petunia, Petunia hybrida Vilm., were evaluated for sensitivity to ozone and the reduction in damage afforded by applications of growth regulating and other chemicals. Plants were exposed to ozone concn at 15, 30, 45, and 60 parts per hundred million (pphm) in a growth chamber for 1.5, 3, and 6 hr at 25°C, 78-88% relative humidity, and an illumination of 2,000 ft-c. Chemicals which retarded internode elongation and promoted dark green color of the foliage reduced visible injury induced by ozone.4,5 The compounds 2,4-dichlorobenzyltributyl phosphonium chloride (CBBP) and succinic acid 2,2-dimethyl hydrazide (SADH) retarded growth and modified sensitivity of the foliage to ozone. Concentration of SADH needed to reduce injury significantly was at least twice that used to retard stem elongation. Adding L. ascorbic acid and a wax coating to the spray solution increased the protection afforded by SADH. Chemicals which did not retard growth of petunia such as the chemical growth retardants (2-chloroethyl) trimethyl ammonium chloride (chlormequat), α-cyclopropyl-α (4-methoxyphenyl)-5-pyrimidine methanol (ancymidol), and the systemic fungicide methyl 1-butylcarbamoyl-2-benzimidazolecarbamate (benomyl) afforded no protection for ozone treated plants. The 65 cvs. were placed in 6 classes based on an average rating of injury after exposures to 4 doses of ozone. Five cvs. were in the very tolerant class and have most potential for use in the development of new petunia cvs. resistant to ozone and possibly to other phytotoxicants.
The Relation of Endogenous Abscisic Acid to the Dwarfing Capability of East Malling Apple Rootstocks1
Authors: Yadava U. L. , Dayton D. F.
Published: August 2022

Roots, shoots, and leaves of 1- and 2-year-old ungrafted plants of EM IX, VII, and I, and roots of EM XVIa, were extracted to detect an inhibitor that appears identical with abscisic acid (ABA). The extracts were coned, partially purified chromatographically, and bioassayed using the wheat coleoptile straight growth and Lepidium seed germination tests. A strongly inhibitory substance was found in both bioassays at or close to the Rf values reported for maximum ABA activity or determined with the synthetic form.

Extracts of EM IX tissue contained the highest levels of this inhibitor, presumed to be ABA. Progressively lower levels were found in extracts of EM VII, I, and XVIa, which is the same as the order of these clones in increasing vigor of grafted scions. This same order was indicated in nearly all bioassays of the 3 types of tissue extracts. Extracts of roots collected in early spring after overwintering either in storage or out-of-doors, in midsummer, and in the fall after cessation of growth all placed the clones in the same order. Levels in root and leaf extracts were generally higher than in those of shoots.

The Lepidium seed bioassay appears to offer a convenient method for identification of strongly or semi-dwarfing individuals or clones. Leaves offer an obvious advantage over shoots or roots.
Endogenous Plant Growth Substances in Developing Fruit of Prunus cerasus L. I. Levels of Extractable Gibberellin-Like Substances in the Seed1
Authors: Naito R. , Inoue H. , Bukovac M. J.
Published: August 2022

Levels of gibberellin (GA)-like substances were determined in sour cherry (Prunus cerasus L.) seed in relation to fruit development using the cucumber and dwarf pea bioassays. Two GA-like substances were found; one was soluble in ethyl acetate and the other, a more polar substance, in butanol. Concentrations of both substances increased to a maximum 14 days after anthesis and then decreased and remained low during Stage III. Changes in seed GA-like substances coincided with development of the seed components, nucellus, endosperm, and embryo, and the early enlargement of the pericarp, but not with subsequent development of the pericarp. Both the ethyl acetate- and butanol-soluble GA-like seed substances chromatographed at a lower Rf than GA3. The butanol-soluble component is probably not a glycoside, since no ethyl acetate-soluble GA was released on hydrolysis. The butanol-soluble component resembles GA32 in polarity, partitioning characteristics and Rf.
Effect of Ethylene on Carnation Keeping Life1
Authors: Barden Laura E. , Hanan Joe J.
Published: August 2022

Carnation (Dianthus caryophyllus L., cv. White Sim) buds and flowers were exposed to various ethylene concn for different periods and at different temp. A dosage term, ppb-hr, was used to evaluate C2H4 concn and exposure time. Keeping life was highly correlated with dosage, depending upon temp. Buds were less susceptible than flowers to C2H4 injury at all temp, with no significant loss of keeping life at the highest dosages and a temp of 1.7°C. Open flowers exhibited zero keeping life with 47,000 ppb-hr at the same temp. At 21.1°C, zero keeping life was obtained with mature flowers at 4,400 ppb-hr, whereas buds required 8,400 ppb-hr. Mathematical relationships showed the effect of increasing C2H4 dosages on rate of keeping loss to be linear. Over a dosage range of 103 to 105 ppb-hr, the effect of temp on open flowers was linear, and slightly curvilinear on buds. Increasing exposure temp from 1.7 to 21.1°C increased the effect of ethylene nearly 1,000 times on open flowers.
A Comparison of Hardiness Responses in Fruit Buds of ‘Bing’ Cherry and ‘Elberta’ Peach1
Authors: Proebsting E. L. , Mills H. H.
Published: August 2022

Several aspects of hardiness behavior in ‘Bing’ cherry and ‘Elberta’ peach fruit buds were compared. Cherries averaged 2.1°C hardier than peaches. The difference was least in late fall and early spring, and greatest during winter. High temp caused the minimum hardiness level of peaches to rise by mid-winter; cherries not until late winter or early spring. Cherries hardened more rapidly than peaches during cold days. During dormancy cherry and peach buds hardened when temp was below -1.1 to -2.2°, dehardened when above that level. Hardening rates up to 1.9° per day for peaches and 2.8° for cherries were observed. Cherry buds hardened by cold days lost 6.1° of hardiness in 4 hr when exposed to 24°C.

Understanding of fruit bud hardiness in peach and cherry has progressed far enough that use of low temp control measures during winter, based on critical temp from laboratory evaluations, seems feasible.
Effects of Subatmospheric Pressure Storage on Ripening and Associated Chemical Changes of Certain Deciduous Fruits1
Authors: Salunkhe D. K. , Wu M. T.
Published: August 2022

Subatmospheric pressure (hypobaric) treatments increased the storage life of apricots by 15 to 37 days, peaches by 7 to 27 days, sweet cherries by 16 to 33 days, pears by 1.5 to 4.5 months, and apples by 2.5 to 3.5 months. In general, chlorophyll and starch degradation, losses of sugars and titratable acidity, and formation of carotenoids were delayed by the subatmospheric pressure treatments.
Effects of Induced Polyploidy in Cucumbers1
Authors: Smith O. S. , Lower R. L.
Published: August 2022

Autotetraploid cucumbers were induced by soaking diploid seed in solutions of colchicine. Triploids were made by reciprocal crosses between diploids and tetraploids. The fruit yield of the polyploids was approx 1/2 that of diploids. The fertility of the tetraploid plants as measured by viable seed was approx 1/5 that of diploids. The reduced seed yields of tetraploids appeared to be due to reduced no. of functional male gametes and genic factors. Differences in seed yields were measured among tetraploid lines. Tetraploid by diploid crosses were extremely infertile in either direction.
Histochemical Localization of Enzymes in the Abscission Zones of Maturing Sour and Sweet Cherry Fruit1
Authors: Poovaiah B. W. , Rasmussen H. P. , Bukovac M. J.
Published: August 2022

Dehydrogenase, acid phosphatase, and peroxidase activities were localized histochemically in the lower (pedicel-fruit) abscission zones of sour (Prunus cerasus L.) and sweet (Prunus avium L.) cherry fruits. Highest enzyme activity generally occurred at the juncture of the receptacle and fruit tissues; the region where separation occurred. Both species had a similar peroxidase isozyme pattern; however, 2 bands in sweet cherry had lower intensities than sour cherry. The implications of localized activities of these enzymes in cherry fruit abscission are discussed.
Morphological Studies of Flower Bud Initiation and Development in Bulbous Iris Stored at Various Temperatures1,3
Authors: Uhring Joseph
Published: August 2022

Flower buds are absent in dormant iris bulbs, but floral initiation occurs after subjecting them to a high temp, heat curing treatment, followed by a holding period at a moderate temp, and then a low temp pre-cooling period. The effects of cultivars, digging dates, ethylene gas treatment, and different storage temp on earliness and uniformity of flowering were studied in microscopic sections of bulb growing points of samples collected at intervals from the different treatment lots. The results indicated that variations in field growing conditions produced bulbs with varying degrees of maturity, of which some would respond properly to curing treatments and others would not. Properly matured bulbs grown in the Pacific Northwest can be heat cured by exposing them to a temp of 32.2°C for 10 days. Holding temp lower than 15.5°C delayed subsequent flower bud initiation. Ethylene gas treatment prior to heat curing appeared to stimulate floral initiation.
Levels of Hydrogen Sulfide Toxic to Citrus Roots1
Authors: Ford H. W.
Published: August 2022

The toxicity level for H2S, generated under waterlogged conditions, is a concn-time relationship associated with the dissolved molecular H2S concn in the root rhizosphere. A molecular concn of 2.8 ppm for 5 days is one toxicity threshold for significant root injury in controlled tests with rough lemon (Citrus jambhiri Lush.) seedlings. Rapid bacterial generation of H2S in the root rhizosphere was indicated by a doubling of the concn every 24 hr. Sulfides were present in root tissues that died.
Effects of Growth-Regulators on Cellulase, Polygalacturonase, Respiration, Color, and Texture of Ripening Tomatoes1
Authors: Babbitt J. K. , Powers M. J. , Patterson M. E.
Published: August 2022

Changes in firmness, protein, color, respiration, cellulase, and polygalacturonase were followed during maturation and ripening of tomatoes, Lycopersicon esculentum L., on the plant and in detached fruit allowed to ripen at 20°C. Cellulase activity in the young fruit increased steadily during the maturation period. Cellulase activity in detached fruit ripened at 20°C increased rapidly during the onset of ripening and reached a higher level than in fruit ripened on the plant. Polygalacturonase activity was not detectable in developing fruit until after the fruit had initiated ripening. Polygalacturonase activity in detached fruit ripened at 20°C did not appear until the onset of the climacteric and then increased rapidly. This corresponded to the polygalacturonase activity in fruit allowed to ripen on the plant.

The changes during ripening appeared to follow a pre-determined pattern. Grow-regulating substances only moderately affected the onset of the climacteric rise, but markedly influenced the time interval to reach the climacteric peak. They also markedly affected the rate of the normal sequence of changes during ripening. Such changes as softening, color formation, and enzyme activities of cellulase and polygalacturonase were accelerated by ethephon and SADH and delayed by gibberellic acid and indoleacetic acid. Gibberellic acid suppressed polygalacturonase activity. After 14 days polygalacturonase activity in the control fruit was 25 times greater than in fruit treated with gibberellic acid. Cellulase activity in gibberellic acid treated fruit increased steadily during this period. The loss of firmness in treated fruit suggests that softening is initiated by action of cellulolytic enzymes and that pectinolytic enzymes are involved in subsequent changes in texture.
Effects of N, P, and K Fertilizer on Leaf Composition, Yield, and Fruit Quality of Bearing ‘Ben Lear’ Cranberries1
Authors: Eaton G. W. , Meehan C. N.
Published: August 2022

Data from a 3-yr experiment on ‘Ben Lear’ cranberries (Vaccinium macrocarpon Ait), by multiple stepwise regression at the 1% level, showed that N, P, and K applications increased their respective tissue levels. Tissue Ca and Mn were decreased by N applications in 1969; 1970 tissue Ca was decreased by applications of both N and P. Nitrogen, P, and K applications all tended to decrease 1969 tissue Mg.

Yield was increased by N applications in 1971. A cubic effect of N applications was noted in 1970 anthocyanin and soluble solids contents. Pooled data for 1970 and 1971 were fitted to linear and quadratic equations relating tissue levels to fertilizer applications and yield and quality measurements to tissue levels. Desirable tissue levels of N, P, K, Ca, Mg, Fe, and Mn are suggested.
Genetic Control of Reaction to Common Blight Bacterium in Bean (Phaseolus vulgaris) as Influenced by Plant Age and Bacterial Multiplication1
Authors: Coyne D. P. , Schuster M. L. , Hill K.
Published: August 2022

Reaction to Xanthomonas phaseoli (E.F. Smith) Dowson, cause of common blight disease in beans, Phaseolus vulgaris L., was inherited quantitatively in the cross early flowering susceptible cv. Great Northern (GN) 1140 × late flowering tolerant line ‘GN Nebr. #1, sel. 27’. F1 populations showed partial dominance for susceptibility at 25 days and nearly complete dominance at 43 days after inoculation. Genes controlling delayed flowering, under long photoperiod and high temp, and tolerant reaction were linked. Early, blight tolerant advanced lines were not obtained by pedigree selection. They were obtained, however, by the backcross method, using ‘GN Nebr. #1, sel. 27’ as the recurrent parent. Different photoperiod × temp regimes in growth chambers induced flowering at the same or different times in nearly-isogenic lines of the same age. Vegetative plants exhibited higher levels of tolerance and lower bacterial populations than did plants in the pod stage. The bacterial population in susceptible ‘GN 1140’ was higher than in early and late tolerant lines.
Activity of Foliar Applied Ancymidol on Girdled Chrysanthemum morifolium Ramat1
Authors: Weisser D. , Sachs R. M.
Published: August 2022

In ‘Bright Golden Anne’ chrysanthemums girdling below the treated leaves does not reduce, rather it may enhance, growth retarding activity of foliar applied ancymidol. Experimental evidence with 14C sucrose shows that the compound does not pass the girdle to enter the root system, and it is assumed that ancymidol transport is similarly restricted. Our results indicate that the major site of action of ancymidol is in the shoot tissues. One suggestion accounting for greater activity of soil, as compared to foliar, applications is that the chrysanthemum root system may absorb ancymidol more rapidly than the leaves.
The Influence of Rootstocks and Interstocks on the Nutrient Concentrations in ‘Valencia’ Orange Leaves1
Authors: Labanauskas C. K. , Bitters W. P.
Published: August 2022

It was clearly demonstrated that rootstocks have a strong influence on nutrient concentrations in scion leaves. The concentrations of Cl and B in leaves from ‘Valencia’ trees on several trifoliate orange rootstocks were 56% and 43%, respectively, higher than in leaves from trees grown on sweet orange rootstock.

The concentration of nutrients in leaves from trees grown on sweet orange rootstocks were not affected by Rubidoux trifoliate (C), Rubidoux trifoliate (A), English small trifoliate, Benecke trifoliate, and Jacobsen trifoliate interstocks.
Insect Pollinators Frequenting Strawberry Blossoms and the Effect of Honey Bees on Yield and Fruit Quality1
Authors: Nye William P. , Anderson J. LaMar
Published: August 2022

Open plots of strawbery (Fragaria sp.) or plots caged with colonies of honey bees (Apis mellifera L.) produced less malformed fruit than plots screened to exclude large insects. Bees and large Diptera, mostly drone flies (Eristalis spp.), were the most numerous visitors to the strawberry blossoms. A list of insects including 108 species representing 35 families frequenting strawberry blossoms in Utah was compiled. The most efficient pollinators were Apis mellifera, Halictus ligatus Say, and Eristalis spp.
Effect of N, P, K, and Lime on Yield, Nut Quality, Tree Growth, and Leaf Analysis of Pecan (Carya illinoensis W.)1
Authors: Worley Ray E.
Published: August 2022

Mature ‘Stuart’ pecan trees in good condition on Tifton loamy sand did not respond to fertilizer [10-4.4-8.3 (N-P-K)] at rates from 0-1344 kg/ha annually over a 10-year period, but color and vigor of trees receiving no fertilizer were reduced near the end of the study. Highest yields were obtained with 448 kg/ha. Fertilizer effects on shoot growth and nut quality were inconsistent, but quality tended to be poorer for heavily fertilized than lightly fertilized trees near the end of the study. Fertilizer and limestone effects on yield and shoot growth were also inconsistent for mature ‘Stuart’ trees on Leefield sand at Way cross, Ga. over a 10-year period. Leaf analysis responded very slowly to nutrient application with leaf N and K being first increased by fertilizer application in the 6th and 9th years, respectively. Fertilizer P had little effect on leaf P. Liming to pH 60 with calcite increased leaf Ca and decreased leaf Mg and Al.

Yield and shoot growth of young ‘Desirable’ trees increased with the first 56 kg/ha increment of N, but further increases due to the second increment were seldom significant. Phosphorus and K additions had little effect on yield and shoot growth, but increasing K reduced nut size. Increasing N rates to 112 kg/ha improved vigor and color of trees. Leaf N and K for young trees increased from increasing application levels the first year, and leaf K was maintained in the desired range when soil test plus applied K equaled 112 kg/ha annually. Increasing N and K applications reduced leaf Mg, and increasing K applications increased leaf Mn, Fe, Al, and Na in young trees.
Effects of Harvest Date and Specific Gravity on Storage Behavior and Raw and Processed Quality of ‘Jonathan’ Apples1
Authors: Shaw Glenn W.
Published: August 2022

The composite specific gravity (SG) of ‘Jonathan’ apples decreased and size increased with each of 3 successive harvest dates. The SG of all but the least dense fruit decreased during storage. Correlation r values of some raw product attributes are shown. Analysis of sauce made from fruits of different SG and stored for up to 4 months showed that separation according to SG at early and late harvest dates may have some value in obtaining a higher quality product.
Host-parasite Interrelations of Lactuca saligna L. and the Cabbage Looper, Trichoplusia ni (Hubner)1
Authors: Whitaker Thomas W. , Kishaba A. N. , Toba H. H.
Published: August 2022

A collection of Lactuca saligna (P.I. 261653), although heterozygous, contained individuals that retard the development of cabbage loopers (Trichoplusia ni Hubner) compared with preferred hosts such as cultivars of lettuce and broccoli. Development of 1st instar to adult required 5 to 6 days longer on L. saligna than on broccoli. Comparable development of lst-instar larvae to 2nd instar required 32 hours more for larvae fed exclusively on leaves of L. saligna than for those confined to L. sativa cv. Hanson. Also, more significantly, in this test 26% of the larvae died before the 2nd-instar stage compared to 0% in the control.

Interspecific hybrids between L. saligna and L. sativa were produced. The F1 plants were fertile to a limited extent. These interspecific crosses will allow an exchange of genes between the 2 species and make possible the development of lettuce cultivars resistant to the cabbage looper.

Five collections of L. saligna (other than P.I. 261653) were evaluated for their effect on looper development from 1st to 2nd instar. A significant delay in larval development was established for 2 entries (P.I. 253299 and P.I. 281876). However, they were more preferred than P.I. 261653 in a preference test. A collection of Lactuca species, consisting of 19 entries were tested for antibiosis. Two entries listed as L. perennis L. were uncovered where development from 1st instar to 2nd instar was suppressed. This result suggests that antibiosis for cabbage looper is not widespread in the genus, but probably fairly common in L. saligna as evidenced by plant to plant variation among numerous collections.
Physical and Chemical Changes Associated With Growth of the Pistachio Nut1
Authors: Crane Julian C. , Al-Shalan Ismat M.
Published: August 2022

Markedly different curves of growth of the pistachio nut were obtained when increases in cross-diameter, fresh weight and dry weight were plotted. The dry weight data indicated that carbohydrates are not involved in abscission of inflorescence buds and resulting alternate bearing, as previously reported.

The predominant sugar in the kernel was sucrose, followed in decreasing order by glucose, fructose, and inositol (a sugar alcohol). Total sugars reached a peak of 43.3% of the dry weight early in development of the kernel, but then decreased to 7% at nut maturity. Concomitantly, crude fat increased from a low of 3.2% early in kernel development to a maximum of 40.1% at maturity.