bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Orchard Fireblight Susceptibility of Young Apple Stions1
Authors: Mowry James B.
Published: August 2022

Marked variations in the number of fireblight infections were observed on 3-year old ‘Double Red Jonathan’ stions grafted on 8 size-controlling clonal rootstocks. The average number of fireblight infections per tree ranged from 33 with the MM 109 rootstock to 0 with the Alnarp 2 rootstock. The number of fireblight infections was correlated with the number of flower clusters on the stions (r= .70**) but was not correlated with stion vigor as expressed by trunk circumference (r=-.18). The number of fireblight infections on non-flowering shoots also was correlated with the number of flower clusters on the stion (r= .60**) but was not correlated with trunk circumference (r= -.20). The susceptibility of non-flowering shoots to fireblight was influenced by the number of flower clusters on the stion, but flowers were not an essential avenue of bacterial infection, even when present. Within the Merton-Mailing rootstock series, the number of flower clusters was not correlated with the size of the stion.
Phytotoxicity Studies with Tetrachloroisophthalonitrile (Termil*) on 12 Cultivars of Poinsettia (Euphorbia pulcherrima)
Authors: Sheldrake R. , Rodebaugh J.
Published: August 2022

In the past two years a new concept of thermal dusting with Tetrachloroisophthalonitrile (Termil) for the control of Botytris cinerea on greenhouse crops of geranium (Pelorgonium hortorum) has proven to be very successful and practical. This fungus frequently causes leaf and bract injury to crops of poinsettia (Euphorbia pulcherrima) in greenhouses in late November and December. This study was initiated to determine the phototoxicity of the commercial product Termil used with the special alcohol burner and applied as a thermal dust.
Highbush Blueberry Pollen Collection by Honeybees
Authors: Eaton G. W. , Stewart M. G.
Published: August 2022

Honeybees are considered to be important pollinators of the highbush blueberry (Vaccinium corymbosum L.) (2). Shimanuki et al. (4) found one honeybee colony which consistently collected a larger proportion of cranberry pollen than did other colonies in the vicinity of a cranberry bog. Differences among colonies in collection of highbush blueberry pollen are reported here.
Incorporating TMV Resistance into Tomato Hybrids1
Authors: Ibarbia E. A. , Lambeth V. N.
Published: August 2022

The practical significance of incorporating TMV resistance into F1 hybrid tomatoes can hardly be over-estimated. Internal browning, graywall and blotchy ripening disorders continue to plague the greenhouse tomato grower and constitute perhaps his greatest current disease problem. Lewis and Taylor (6) pointed out the confusion which exists with regard to the association of TMV with these disorders.
Seasonal Distribution of Manganese in Leaves and Shoots of Red Delicious Apple Trees Showing Internal Bark Necrosis (IBN)
Authors: Zeiger D. C. , Shelton J. E.
Published: August 2022

Mn in apple leaves rose to a late summer maximum prior to or at abscission. The average levels, or the maxima, were not related to the severity of IBN symptoms. There are indications, but no conclusive evidence, that some withdrawal into the bark of shoots may occur. If such movement does occur, the resulting increase in bark Mn concentration is not great and cannot account for levels of bark Mn associated with IBN by Berg, et al. (1). No redistribution of Mn between bark and wood appears to occur during the winter.
Effect of Preharvest Sprays of Ethrel, Alar, Malathion on Anthocyanin Content of Early Black Cranberry (Vaccinium macrocarpon Ait.)1
Authors: Eck Paul
Published: August 2022

Ethrel at 600 ppm applied as a 200 gal/A preharvest spray to ‘Early Black’ cranberry increased anthocyanin development. Gardner Color Difference Meter readings of fresh fruit indicated that Alar-treated fruit had higher reflectance than control fruits suggesting a delay in surface coloring. Ethrel, Alar, and malathion preharvest sprays did not influence yield or size of the fruit.
Mechanization in Agriculture
Authors: Bainer Roy
Published: August 2022

The strong position of the United States in today's world is largely due to a prospering mechanized agricultural industry-an industry that produces the nation's food and fiber in abundance with around 6 per cent of the nation's working force on the production line. The millions released from producing the necessities of life are freed to other industries, services and professions, thereby contributing to America's remarkable industrial expansion and the prevailing high standard of living.
Plant Analysis and Fertilizer Problems Volume IV
Authors: Bould C. , Prevot P. , Magness J. R.
Published: August 2022

This hardbacked, 430-page volume contains papers presented at the Fourth Colloquim on Plant Analysis and Fertilizer Problems held at Brussels, Belgium in September 1962 in connection with the 16th International Horticultural Congress.
Yield Response of Peas to Foliar Application of Dimethyl Sulfoxide and Cycocel1
Authors: Maurer A. R. , Ormrod D. P. , Adedipe N. O.
Published: August 2022

In field trials at two locations in British Columbia, dimethyl sulfoxide applied as a 5% foliar spray, increased the yield of ‘Dark Skin’ Perfection’ peas by 11.5 and 25.3%. The foliar application of Cycocel at 50 ppm increased yield by 14.6 and 17.4%. The effects of DMSO and Cycocel were additive, there being no interaction.
Reciprocal Grafting of Normal and Dwarf Solo Papaya on Growth and Yield1
Authors: Lange A. H.
Published: August 2022

Scions from ‘Solo’ papaya trees of normal size grafted on dwarf ‘Solo’ stocks resulted in trees with less vigor. Flowering and fruit production occured lower on the stem. The total quantity of fruit was smaller than on normal ‘Solo’ trees.

Dwarf ‘Solo’ scions grafted on normal ‘Solo’ stocks resulted in vigorous trees flowering and producing fruit higher on the stem; there was also more fruit, with less crowding, than on dwarf ‘Solo’.
Pine Mortality Along Michigan Highways1
Authors: Davidson Harold
Published: August 2022

During the spring and fall of 1966, three thousand one hundred and forty-nine pine trees were planted along the Interstate Highway System in Michigan as part of the highway beautification program. The species included: Pinus nigra (Arnold) Austrian pine; P. resinosa (Aiton) red pine; P. strobus (1.) white pine; and P. sylvestris (L.) Scots pine. Plants ranged in size from two feet for some of the red pine, up to six feet for some of the white pine, but most plants averaged four to five feet in height. Specifications required: “that all plants be nursery grown and shall qualify under the AAN Horticultural Standards for the current American Standards for Nursery Stock, ASA Specification Z 60.1.” All of the plantings were made by landscape contractors, who were the successful bidders for each project.
A Technique for Soil Application of a Growth Retardant1
Authors: Holcomb Edmund Jay , White John W.
Published: August 2022

The effectiveness of applying a growth retardant gradually in the irrigation water over an extended portion of the crop cycle was investigated. Cycocel can be applied effectively in this manner and control of plant height is comparable to that produced by a single drench application.
A Rapid Method for Obtaining Leaf Samples for Electron Microscopy
Authors: Campbell William F. , Evans John O.
Published: August 2022

This report, describes a rapid and convenient method to obtain leaf disc samples for electron microscopy. It was developed in connection with bio-chemical-ultrastructural studies of herbicidal effects on protein synthesis. It was important to speed up the sampling time and to obtain uniformly sized samples.
The Relationship of Sulfur Fumes to Defoliation and Fruit Drop of Apples1
Authors: Hoyt S. C. , Benson N. R. , Burts E. C.
Published: August 2022

In early September 1963, extensive leaf drop on Winesap apple trees was reported from an orchard in Yakima County, Washington. Later a high percentage of fruit dropped prematurely, and the remaining fruit failed to color and mature normally.
Metabolic Control of Ripening1
Authors: Looney N. E.
Published: August 2022

It is generally agreed that fruit ripening is a biologically active process often involving high metabolic activity, increased activity of some enzyme systems, and ultimately in fleshy fruits, deterioration of the organ. These events occur in nature only at the proper physiological stage indicating that natural control systems operate to prevent premature ripening. Because of the dynamic nature of ripening in many species, it is probable that endogenous control systems also function to initiate ripening at the proper stage of ontogeny. The presence of these natural control mechanisms suggest that ripening may be subject to manipulation by horticultural, physiological or biochemical means and indeed, we are becoming increasingly aware of and conversant with concepts and techniques leading to control of this important plant process.
Dimethyl Sulfoxide as an Adjuvant of Colchicine in the Treatment of Rubus Seeds and Shoot Apices1
Authors: Sanders Hosea , Hull J. W.
Published: August 2022

The addition of dimethyl sulfoxide (DMSO) to a colchicine solution applied to germinating black raspberry seed increased the percentage of induced polyploids more than did colchicine alone. Concentrations of DMSO higher than 2% were phytotoxic to germinating seeds when combined with colchicine. DMSO had no discernible effect on penetration of colchicine to the apical dome in blackberry shoot apices. There was evidence of synergistic effect of the chemicals on phytotoxicity of apical tissue.
Relationship Between Length of Vernalization, Stem Apex Size, and Initiatory Activity in Lilium longiflorum cv. ‘Ace‘1
Authors: Wang S. Y. , Roberts A. N. , Blaney L. T.
Published: August 2022

A study of shoot apex size and initiatory activity in August-harvested ‘Ace’ bulbs following 0, 6, and 18 weeks vernalization at 40°F showed negetative correlations between leaf and flower number and length of vernalization treatment, and between apex size and this cold treatment. Growth acceleration as reflected in earlier shoot emergence, internode elongation and rapid leaf unfolding was evident following 6 weeks’ 40°F storage, but prolonged (18 weeks) treatment drastically reduced subsequently initiatory activity and rate of leaf unfolding.
A Precision Controlled Atmosphere Storage1
Authors: Greene George M.
Published: August 2022

An inexpensive, versatile, and simple recirculating controlled atmosphere storage system was designed, constructed and tested. It is demonstrated that this controlled atmosphere storage system has minimal variation in O2 and CO2 composition. In addition, the system allows controlled atmosphere research to be conducted in conventional storages that are otherwise unsuited for this type of research.
Introduction to the Symposium
Authors: Dickson Michael H.
Published: August 2022

Quality is rather nebulous and often difficult to measure objectively. This is not surprising since edible quality comprises a number of attributes, both physical and chemical. Some of the components of quality have been measured objectively for a long time; others, such as flavor and aroma, have only recently been measured objectively. Previously they were, and in most cases they still are, subject to personal preferences and prejudices.
Vegetable Flavor
Authors: Allen Stevens M.
Published: August 2022

The instrumentation required for objective evaluation of flavor has been available for only a decade and a half. Most information on the chemistry of flavor has accumulated within the past 5 years. There have been few studies on intercultivar variation of compounds important to flavor. Because an appreciation of the physiology of flavor and an understanding of flavor chemistry are basic to the genetics of flavor, it seems appropriate to discuss briefly these topics.
Natural and Synthetic Sweeteners1
Authors: Inglett G. E.
Published: August 2022

G. E. Inglett earned his PhD in biochemistry at the State University of Iowa in 1952. He has worked with biological toxins at the University of Illinois, 1952-1954, and in cancer research with the U. S. Public Health Service, 1954-1956. He has been a food chemist with the Corn Products Company, 1956-1960, Griffith Laboratories, 1960-1963, and International Minerals and Chemical Corporation, 1963-1966. Although Dr. Inglett is presently associated with the Cereal Properties Laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture at Peoria, Illinois, this paper is based on experience prior to joining the USDA.
Effects of Gibberellin and Alar Sprays upon Fruit Set, Seed Development, and Flowering of ‘Bartlett’ Pear1
Authors: Dennis F. G. , Edgerton L. J. , Parker K. G.
Published: August 2022

Spray applications of gibberellic acid (GA3) were tested for their effects in increasing fruit set when applied during bloom in two commercial pear orchards in which cross-pollination was limited. No beneficial effects were obtained, and flower bud formation was inhibited at concentrations of 20 to 100 ppm. In one year, the inhibitory effect of GA3 upon flowering was partially offset by spraying with 500 or 1000 ppm of succinic acid, 2,2-dimethylhydrazide (Alar) at petal fall.
Physiological Differences Between a Green and a Tan Dry Podded Line of Snap Bean1
Authors: Bouwkamp J. C. , Honma S.
Published: August 2022

A green and tan dry podded line of snap bean was compared with respect to respiration rate, chlorophyll degradation, % dry matter of the leaves, effects of light and Ethrel treatment on abscission of petiole expiants, and fresh weight increase of leaf discs floated on a nutrient solution. The green dry podded Une respired at a higher rate, degraded chlorphyll at a slower rate and contained a higher percentage of dry matter than the tan dry podded line. Petiole explants from the green dry podded line abscised faster in the dark and slower in the light than petiole explants from the tan dry podded line. Ethrel treatment of petiole explants resulted in promotion of abscission in both phenotypes but did not change the relative rates of abscission. Fresh weight increase in leaf discs floated in nutrient solution was greater than for the green dry podded line than the tan. These observations suggest that the green dry podded line has a higher endogenous level of kinetin or kinetin-like substance.
Incompatibilities Between Herbicides and Insecticides in Direct-Seeded Brassica Crops1
Authors: Freeman Jack A. , Finlayson D. G.
Published: August 2022

The compatibility of 5 preemergence herbicides and 3 insecticides applied in silt loam was assessed in 4 brassica crops by comparing their effects on germination, plant stand, and yield. Several combinations were deleterious. The herbicides CDEC and DCPA in combination with the insecticide thionazin reduced plant stand in cabbage and cauliflower. Herbicide C-7019 in combination with the insecticide fensulfothion was incompatible for cabbage and broccoli. Cabbage germination was reduced; while with broccoli both the germination and crop yield were affected. C-7019 alone reduced the germination of cauliflower and in combination with fensulfothion the damage was increased. This herbicide was phytotoxic to rutabaga. When nitrofen was combined with the insecticides, plant stands of cauliflower and rutabaga were affected. Nitrofen and thionazin together reduced the plant stand of cabbage. Propachlor at 4 lb./acre was compatible with any of the three insecticides for the four crops. However, the plant stand and yields of all four crops were reduced in plots treated with propachlor at 6 lb./acre in combination with thionazin. Propachlor with the insecticide carbofuran injured only broccoli. The herbicides did not affect the efficacy of the insecticides.
Environmental Pollution: A Dual Problem for Horticulture
Authors: Ryder Edward J.
Published: August 2022

It is said that environmental pollution is a cause that everybody can identify with, perhaps because it is so easy to blame others for it. Yet a little closer inquiry will show that nearly all of us contribute to pollution. The automobile emits polluting substances, but only when we drive it. High phosphate detergents cause eutrophication in our fresh waters, but only because we wash with them. We buy the products of the steel industry, and we use the electricity provided by the power companies.
Effect of Auxin-Herbicides on Plant and Animal Biochemistry1
Authors: Cherry Joe H.
Published: August 2022

Joe H. Cherry received his BS from the University of Tennessee (1957) and MS (1959) and PhD (1961) from the University of Illinois. He spent a year at the Seed Protein Pioneering Research Laboratory, U. S. Department of Agriculture, in New Orleans before coming to Purdue in 1962 where he is now Professor of Horticulture. A “Molecular Horticulturist” and proud of it, Dr. Cherry believes that the exciting arena for horticulture today is unraveling the biochemistry of gene action in relation to regulation of fundamental plant processes.
Preparing Slides to Show at Scientific Meetings
Authors: Maxie E. C. , Nelson K. E.
Published: August 2022

Success in presenting a paper at meetings of the Society requires that slides be of high quality and properly used. A paper has only one purpose- to inform. A slide has only one purpose- to portray information for quick understanding.
2, 4-D as an Air Pollutant: Effects on Growth of Representative Horticultural Plants1
Authors: Sherwood C. H. , Weigle J. L. , Denisen E. L.
Published: August 2022

Experimental techniques are described for concentric circular test patterns with intentional exposure to a 2,4-D source at the center. With the intensity of exposure as a function of distance from the center, various degrees and symptoms of expression of 2,4-D damage were obtained for a wide variety of horticultural plants. Observations were made on overwintering damage, carry-over effects on potted specimens returned to the greenhouse, seed carry-over effects (none), and effects on virus-infected plants.
2, 4-D as an Air Pollutant: Effects on Market Quality of Several Horticultural Crops1
Authors: Weigle J. L. , Denisen E. L. , Sherwood C. H.
Published: August 2022

Crops were grown in field plots under plastic-covered greenhouses for 3 years under ambient, charcoal-filtered, and charcoal-filtered with 2,4-D added atmospheres. No differences in market quality were found with green beans and raspberries. Deformed fruit in strawberries, uneven berry ripening in grapes, and blotchy ripening and deformed fruit in tomatoes occurred in “2,4-D added” treatment but not in “charcoal-filtered” treatment, while “ambient” was generally intermediate. The amount of 2,4–D in the atmosphere also influenced yields of grapes and strawberries.
Rusty-Brown Discoloration, a Serious Market Disorder of Western Winter Head Lettuce1
Authors: Ceponis M. J. , Porter F. M. , Kaufman J.
Published: August 2022

A serious market disorder of California and Arizona crisp-head lettuce is described and named “rusty-brown discoloration.” The disorder occurs in lettuce marketed during January-April, with a pronounced maximum in February. Losses on the New York market have increased steadily in recent years and were particularly severe in 1969. In February 1969, 90% of all western lettuce shipments inspected on the market were commercially damaged. Studies made with freshly harvested, air-shipped lettuce showed that the disorder increased markedly during 7-10 days’ storage at refrigerated temperatures. There was less rusty-brown discoloration development at 45° and 50° than at temperatures below 40°F. The cause of the disorder is not known.
Effects of Certain Soil Fumigants on Essential Nutritive Components and the Respiratory Rate of Carrot1 (Daucus carota L.) Roots
Authors: Wu Maureen , Singh B. , Wu M. T. , Salunkhe D. K. , Dull G. G.
Published: August 2022

Telone (10, 20, 30 gal/acre) and Nemagon (1, 2, 3 gal/acre) were applied to the soil one week before planting of carrots. Compared to the untreated controls, the roots of the treated plants had a significantly higher content of total carotene, β-carotene and total sugars and a lower rate of respiration.
Effect of Succinic Acid 2,2-Dimethylhyrazide on the Growth of Marigold in Long and Short Photoperiods1
Authors: McConnell Dennis B. , Esther Struckmeyer B.
Published: August 2022

Succinic acid 2, 2-dimethylhydrazide (Alar) was applied as a foliar spray to ‘Sovereign’, an F1 cultivar of Tagetes erecta L., grown in a complete nutrient solution. Alar was applied weekly as a foliar spray at concn of 500, 1000, and 2000 ppm to plants grown under both short and long days. Short day control plants were shorter, flowered earlier, and had shorter leaves than the long day control plants. In each photoperiod, all plants treated with Alar were significantly shorter than the controls because of shorter in tern odes. Dry wt of the tops of treated plants were significantly less than the controls, but the dry wt of the roots were not significantly different. Leaf length and no. of nodes were not affected by the different concn. In short days, Alar delayed flowering up to 8 days, but did not affect the size of the terminal flower.
Photoperiodic Effects on Lilium longiflorum cv. ‘Georgia’ Grown by the Controlled Temperature Forcing Method1
Authors: Carlson William H. , Carpenter William J.
Published: August 2022

The effects of daylength during the 63°F lily rooting period prior to 40° storage and the duration and scheduling of the storage period were determined for Japanese-grown ‘Georgia’ lilies. Benefits from the Controlled Temperature Forcing (CTF) method for increased flower buds and leaves were lost if used with 16-hr day lengths during the 63° period before storage. Artificial fluorescent light of 5 watts per ft2 to create a 16-hr daylength was found adequate to reduce the CTF effects. The length of the 63° period prior to cold treatment affected the days from bulb planting to flowering, no. of flowers, plant height, and no. of leaves. These results were similar at both the 10 and 16-hr day lengths. The effects of 6 week 40° cold period decline at both photoperiods as the duration of the 63° period before storage increases. Delaying the 40° cold period until 10 weeks after planting at the 16-hr daylength resulted in flowering only 4 days before lilies receiving no cold treatment.
Relation of Fall and Winter Temperatures to Flower Bud Behavior and Wood Hardiness of Deciduous Fruit Trees
Authors: Proebsting E. L.
Published: August 2022

As pomologists, our primary responsibility is to fruit trees growing in the frequently hostile environments which we insist on calling “fruit sites.” For most of the country the most consistently and effectively hostile element in a fruit tree’s environment is low temperature.
Crop Protection by Heating, Wind Machines, and Overhead Irrigation1
Authors: Gerber J. F.
Published: August 2022

Cold weather can change the yield of fruit crops faster than any other factor. This change may range from mild effects to total disaster involving not only the current year’s crop, but also future year’s. Much effort has gone into the protection of fruit crops from the damage of cold weather by the producer; much less effort has been spent by the researcher. No doubt, a part of the reason is the multitude of disciplines that are required to solve the problem of prevention of cold injury by microclimatic modification.
A Further Note on Longevity of Strawberry Seed in Cold Storage1
Authors: Scott D. H. , Draper A. D.
Published: August 2022

In a germination test with strawberry seed of different ages stored at 40°F, 23-year-old seed germinated as well as 1-year-old seed. Germination was relatively high for all of the seed lots, despite differences in age.
Effect of Daylength on pH and Soluble Solids Content in Tomato (Lycopersicon esculentum L.)1
Authors: Sinnadurai Suppiah , Amuti Kofi
Published: August 2022

In 6 tomato cultivars soluble solids of fruits significantly increased under 16 hr as compared to 12 hr daylength but pH remained fairly constant.
A Tissue Culture Technique for Studying Chilling Injury of Tropical and Subtropical Fruits1
Authors: Vakis N. , Grierson W. , Soule J. , Albrigo L. G.
Published: August 2022

Visual observations of chilling-injury symptoms and respiration data indicated that discs from ‘Lacatan’ banana, ‘Taylor’ avocado, ‘Key’ and ‘Persian’ limes, and ‘Marsh’ grapefruit on tissue-culture medium and intact fruits had similar responses when stored at chilling and non-chilling temperatures.
Graduate Programs in Horticulture
Authors: Krezdorn A. H.
Published: August 2022

There is much ferment among horticulturists as to the posture of horticultural research and teaching. Some question the very existence of horticulture as a science and the need for graduate degrees in a commodity-oriented field.
Are We Training Our Students for the Job?
Authors: Floate Ray
Published: August 2022

The opportunity of participating in this program is certainly a challenge. Although I am not an expert in the field of education or personnel relations, I believe that I do know something about the kind of people we need to successfully operate a fruit and vegetable processing business.
Cucumber Sex Expression Modified by Growth Regulators1
Authors: Freytag A. H. , Lira E. P. , Isleib D. R.
Published: August 2022

Application of 2,3,5-triiodobenzoic acid (10 ppm) to monoecious cucumber plants at the first true leaf has produced predominately staminate flowers on treated plants while treatment with 2-chloroethylphosphonic acid (100 ppm) resulted in predominately pistillate flowers on treated plants. These 2 growth regulators applied together produced about the same effect as 2-chloroethylphosphonic acid alone.
Changes in Endogenous Growth Substances in the Embryos of Juglans regia During Stratification1
Authors: Martin George C. , Iona M. , Mason R. , Forde Harold I.
Published: August 2022

Kernels from Juglans regia walnuts stratified at 0°C were sampled at weekly intervals and extracted with methanol. The extracts were partitioned into 4 phases which were water, neutral ether, acidic ether and acidic butanol, then bioassayed for cytokinins, gibberellins, auxins and inhibitors. No cytokinins nor gibberellins were found in the tissue. There was activity analogous to that from auxins. An inhibitor which diminished during stratification was found. This inhibitor is believed to be abscisic acid, on the basis of UV absorption spectrum, Rf values established by co-chromatography on paper and silica gel plates, and derivatives analyzed by gas liquid chromatography.
Effect of Cytokinins and Gibberellins on Shape of ‘Delicious’ Apple Fruits1
Authors: Williams M. W. , Stahly E. A.
Published: August 2022

The application of cytokinins and gibberellins alone and in combination to ‘Delicious’ apples just after full bloom affected fruit shape by increasing the length-to-diameter ratio of the fruits. Cytokinins caused fruits to be longer with prominent well-developed calyx lobes. The treated fruit had the appearance of fruits grown where early season temperatures are cool. Gibberellin A4 + A7 caused fruits to be longer but did not appreciably affect the development of the calyx lobes.
Chemical Thinning of Apple Trees Using Concentrate Sprays1
Authors: Rogers B. L. , Thompson A. H.
Published: August 2022

Sevin was used in thinning sprays in dilute—1x—and concentrate form—ranging from 3X to 33X —over a 4-year period on mature ‘Rome Beauty’ apple trees. Although treatments were not the same in each year, all sprays applied significantly thinned in 3 out of 4 years. There was some evidence that concentrate sprays thinned less than dilute sprays, but usually not significantly so. When using 33X concentrates, significant thinning was achieved in 1 year when Sevin was used at full strength—33 lb./100 gal. Approximately the same degree of thinning was obtained when the rate was reduced by one-half. Adding pesticides commonly used in petal-fall sprays to Sevin—all concentrated to the same extent—did not alter significantly the thinning obtained with Sevin alone.

Results on ‘Jonathan’ apples in a 1-year experiment revealed significant thinning with NAD and Sevin in a dilute spray, as well as Sevin at 3X and 6X concentrates. In a 1-year experiment on ‘Golden Delicious’, NAA thinned significantly as a dilute spray, and at 3X and 6X concentrates. The dilute spray was more effective.
Vegetative and Reproductive Responses of Highbush Blueberry to Succinic Acid 2, 2-Dimethyl hydrazide (Alar)1
Authors: Hapitan Jose C. , Shutak V. G. , Kitchin J. T.
Published: August 2022

One spray application of 5000 ppm succinic acid 2, 2-dimethyl hydrazide (Alar) on July 18 or August 22, or 2 spray applications, one on July 18 and another on August 22, significantly retarded new shoot elongation of ‘Collins’ and ‘Bluecrop’ highbush blueberries. The number of flower buds per unit length of new growth was increased. Blossom opening and ripening of the berries was delayed, but fruit size was not appreciably affected. All responses of the 2 cultivars to treatments were more pronounced when they received the 2 spray applications.
Interactions of Applied Growth Regulators and Temperature on Root Initiation in Salix Cuttings1
Authors: Domanski R. , Kozlowski T. T. , Sasaki S.
Published: August 2022

The effects of various combinations of naphthaleneacetic acid (NAA), gibberellic acid (GA), and benzyladenine (BA) at 5 or 50 ppm of each and temperature (22 and 25°C) on root initiation in Salix viminalis, L. cuttings were studied. Highly significant influences of temperature, exogenous growth regulators, and temperature-growth regulator interactions on root initiation were demonstrated. Root formation generally was stimulated by increasing temperature from 22 to 25°. NAA stimulated root formation markedly and its effects were further enhanced for at least 10 days by increasing temperature from 22 to 25°. In contrast to NAA, both GA and BA inhibited root initiation. The inhibitory effect of GA was greater at 25 than at 22°; BA had the greater depressive effect at 22°. Addition of GA or BA, or both, to NAA generally reduced the stimulation of root formation by NAA. As temperature increased toward an optimum for root initiation the balance of endogenous growth regulators and possible cofactors may have changed to bring out the stimulatory effects of auxins over the inhibitory influences of cytokinins and gibberellins.
Use of Centrifugation to Obtain Auxin Extracts from Cuttings Treated with Terminal Applications of 3-indoleacetic Acid1
Authors: McGuire John J. , Albert Luke S. , Shutak V. G.
Published: August 2022

A method of extracting indole compounds from stem segments of woody cuttings of Ilex crenata ‘Convexa’ by refrigerated centrifugation has been developed. Effective extraction was obtained when segments were immersed in a solution of 40% ethanol (v/v) and exposed to a force of 2750 X g for at least 2 hr. Exposure to that force for more than 4 hr did not result in a significant increase in extractable auxin. Quantitative determinations of 14C measured by liquid scintillation counts of the extracts revealed that this method reliably depicted changes in levels of IAA or its metabolized forms in different stem segments as a result of different treatments. Chromatographic separation of extracts revealed that at least 35% of the label was still in the form of IAA after 48 hr. The increased levels of auxin in stem segments was also portrayed by significant rooting increases as determined by rooting index. Centrifugation extracts separated into 2 phases and were removed separately, most of the isotope was contained in the smaller lower phase. Proportionate levels of the 2 phases changed in segments over time and the lower phase disappeared at the time of rooting.
Laboratory Studies on the Effects of Chemicals on the Coloration of Apples1
Authors: Smock R. M.
Published: August 2022

Post harvest screening of compounds that might influence coloration of apples was done in the laboratory. A number of carbonates such as glycol carbonate and carbonate buffers increased anthocyanin development. Certain compounds that were phytotoxic increased coloration. Other compounds such as chloro-IPC, quercetin, and sym-dimethyl diphenylurea decreased coloration. Diuron decreased coloration at relatively high concentrations and increased it at 10 ppm. The possible side effects of this compound are not yet known. Monuron at 10 ppm also increased coloration.
Abscisic Acid, a Component of the Beta-inhibitor Complex in the Prunus Endocarp1
Authors: Ryugo Kay
Published: August 2022

Aqueous and ethanolic extracts of the Prunus endocarp were found to delay germination and subsequent growth of peach, almond, cucumber and plantago embryos. Constituents in the extracts were partially purified by chromatographic separation on paper and thin-layer plates. While there are several components in the inhibitor complex, one has been identified tentatively as abscisic acid3 by its Rf values in different solvent systems, reactions with chromogenic reagents and absorption of ultraviolet light. Most of the inhibitors in the endocarp were fixed on anion exchange resins but not on nylon or hide powder. Mild acid hydrolysis of the endocarp yielded no HCN which eliminates cyanoglucosides as having a role in the inhibition. The extractives induced a marked reduction in oxygen uptake by germinating pea seedlings and growth inhibition in cucumbers. The latter was reversible with gibberellic acid (GA).
Influence of Preharvest Applications of Malathion and Indole-3-Acetic Acid on Anthocyanin Development in Vaccinium macrocarpon, var. ‘Early Black’1
Authors: Devlin Robert M. , Zuckerman Bert M. , Demoranville I. E.
Published: August 2022

The purpose of this study was to test the effect of malathion and IAA on color development in the cultivated cranberry, Vaccinium macrocarpon var. ‘Early Black’. Dosage and time of application were evaluated. Quantitative analyses for antho-cyanins of berries fresh-frozen at harvest showed that applications of 800, 1600, 2400 ppm malathion all caused a highly significant increase in color. Applications of IAA at 30 and 50 ppm did not affect color development. Treated and untreated berries were also analyzed for anthocyanin development after 7 and 14 days in common storage. No significant differences in size or yield were observed between treated and untreated berries. It was concluded that malathion applied 2 weeks before harvest at 1600 ppm would give good color enhancement and still be within the label restrictions for the use of this material on cranberries.
Pre-emergence Weed Control in Young Deciduous Fruit Trees1
Authors: Lange A. H. , Crane J. C. , Fischer W. B. , Roberts K. O. , Elmore C. L.
Published: August 2022

A number of pre-emergence soil residual herbicides were tested at 2 locations on varieties of young peach, plum, cherry, pear and walnut rootstocks. The greatest variation in response resulted from differences in location. Important differences in varietal response were also obtained with the various herbicides in light soils. Simazine appeared sufficiently safe to trees in heavier soil but gave variable weed control. Diuron gave about the same degree of weed control but more safety than simazine on young trees. Of the uracil herbicides tested, DP-733 was the least toxic to the fruit tree species tested, while bromacil and isocil were generally the most toxic, except to peach trees. Of the commercial uracil herbicides, only DP-732 (terbacil) was of sufficient interest for further study.
Carotenes, Xanthophylls, and Color in Carrot Varieties and Lines as Affected by Growing Temperatures1
Authors: Bradley G. A. , Rhodes B. B.
Published: August 2022

Eleven of 39 varieties and lines resulted in good canned slice color in both unusually warm and unusually cool growing seasons for carrots. A number of lines showed seasonal interaction in color, with better color in the cool season, while others resulted in consistently fair or poor color in both growing seasons. No single pigment was highly correlated with color across the range of environmental and genetic diversity encountered in the study. Beta-carotene was the only single component showing a significant positive correlation with color. The highest multiple relationship with color considered beta-carotene, other carotenes except alpha carotene, and xanthophylls. Within a season this multiple correlation accounted for 47 to 50% of the color variance (R of .710 for spring and .686 for fall grown carrots).
The Influence of Population Density and Competition on Phenotypic Stability of Tomato Plants1
Authors: George B. F. , Peirce L. C.
Published: August 2022

Three varieties, ‘Red Top’, ‘Fireball’ and ‘Valiant,’ and their hybrids were grown in a split-plot design of mixed and pure populations at high and low population densities. The frequencies with which varieties or hybrids were selected for earliness and fruit size within high density (1 ft in-row spacing) and low density (3 ft in-row spacing) plots when genotypes were mixed did not differ significantly. Selections for concentrated ripening within the 2 densities were significantly different. The mean response of hybrids to density change was not significant. The mean response of inbreds to density change was significantly different for earliness and fruit size. Fruit size of the inbreds was also affected by competition when grown in mixed stands.
A Morphological Study on the Time of Reproductive Differentiation of the Apical Meristem of Brassica oleracea L. var. italica, Plenck, cv. ‘Coastal’1
Authors: Gauss James F. , Taylor George A.
Published: August 2022

Various histological criteria were employed in studying the chronological and morphological development of the apex of field-grown plants of Brassica oleracea var. italica, cv. ‘Coastal’. Time of differentiation was based on changes in the size and configuration of the apex. The earliest evidence of reproductive differentiation was 5 weeks after sowing or at the time of macroscopic appearance and unfolding of the eighth true leaf. First order floral stalks began to appear at 7 weeks or at the time of macroscopic appearance of the 14th true leaf. Thus, the time interval for the transition from a vegetative to a reproductive apex appears to be approximately 2 weeks, under field conditions. By 9 weeks after sowing, or after the macroscopic appearance of the 22nd true leaf, second order floral stalk initiation and hence inflorescent head formation predominated.
Some Effects of a Growth Retardant on Shoot Meristems of Apple1
Authors: Wilde Mary H. , Edgerton L. J.
Published: August 2022

Uniform, actively growing apple seedlings, 10-15 cm high, were sprayed with 1000 ppm succinamic acid 2-2 dimethyl hydrazide (Alar). The apical portion of treated and control seedlings was collected at the following intervals after treatment: 3, 27 hr; 3, 6, 8, 14 days; 5 weeks. Sections through the apex were prepared, stained and examined microscopically for mitotic figures. As compared with controls, the frequency of mitotic figures in the stem apex of treated plants progressively decreased through 3 days, thereafter the number of figures increased to 69% of that in untreated plants on the 14th day. In the rib meristem frequency of mitosis declined slightly at 3 hr, then progressively until the 3rd day, after which the number of figures increased progressively to the 14th day when it was 28% of that in untreated plants. Only a temporary decrease in mitotic activity occurred in young leaf primordia during the first 6 days. Five weeks old treated seedlings were examined for histological abnormalities associated with extreme shortening of internodes.
Degreening of Citrus Fruits in Response to Varying Levels of Oxygen and Ethylene
Authors: Jahn Otto L. , Chace William G. , Cubbedge Randall H.
Published: August 2022

The responses of ‘Hamlin’ oranges to varying levels of oxygen and ethylene were studied in a series of tests during the fall of 1967. Increasing ethylene levels up to 5 to 10 ppm resulted in rapid losses of chlorophyll. With 2 days’ degreening, the optimum ethylene level appeared to be higher than during a 1-day period. High oxygen (50%) alone increased the rate of degreening, but high oxygen plus ethylene did not produce any additive degreening response over ethylene alone. Low oxygen (10%) reduced the degreening response to ethylene in both ‘Hamlin’ and ‘Washington’ Navel oranges. In a test on ‘Dancy’ tangerines, the rate of degreening was slower at 70° than at 85°F. Degreening frequently continued after removal from the degreening atmospheres, resulting in modification or elimination of original treatment differences.
Growth Response of One-Year-Old Pecan Seedlings, Carya illinoensis, Koch, in Sand Culture to Various Levels of Potassium123
Authors: Upson J. R. , Sparks Darrell
Published: August 2022

The growth response of 1-year-old pecan seedlings in sand culture to various levels (0, 60, 120, 240, 615, 990, 1365, and 1740 ppm) of K was determined.

Leaves of the plants receiving no K exhibited deficiency symptoms; and those receiving 1740 ppm K exhibited toxicity symptoms. In both cases, plant dry weight was suppressed when compared to plants grown with intermediate levels of K (60 to 1365 ppm). Growth response (weight of roots, stems, and leaves) to intermediate treatments of K was normal and did not vary significantly.

In all tissues, increase in per cent K was a diminishing response to the increasing supply of K in the nutrient solution. Per cent K in the leaf or leaflet was a better indicator of K availability than K in the roots or stems. Potassium in the leaf or leaflets was equally reliable indicator of K availability, but the percentages of K associated with a given availability varied with the tissue sampled and the time of sampling. Under the conditions of this study, the data indicate that K deficiency will probably occur when K, on a leaf dry weight basis, falls to some value below 1.0%.
Comparison of Staminate Flower Production on Gynoecious Strains of Cucumbers, Cucumis sativus L., by Pure Gibberellins (A3, A4, A7, A13) and Mixtures1
Authors: Clark R. K. , Kenney D. S.
Published: August 2022

The mixture of GA4 and GA7 was effective in staminate flower production in gynoecious cucumbers and was nearly equal to pure GA7. Although GA13 produced male flowers on gynoecious cucumbers, it is much less active than GA7 or the mixture of GA4 and GA7.
Fertility Levels in Soil-Substitute Media: Their Influence on Transplant Development, Macro-Nutrient Content, and Yield in Tomato1
Authors: Knavel Dean E.
Published: August 2022

Tomato transplants were grown in soil-substitutes of peat moss-Turface and peat moss-perlite. Nutrients were added to the mixtures in factorial combinations by varying the levels of N, P, K, and dolomite. Plants grown in peat-Turface were taller and heavier than those grown in peat-per-lite. In either medium, plants grown with the high level (10 lb./yd3) of dolomite were taller than the plants grown with the low level (5 lb./yd3) of dolomite. Plants grown in peat-Turface contained more N, K, and Ca than did the plants grown in peat perlite. Plants grown in peat-perlite contained more P than plants grown in peat-Turface. The growing medium had no influence on Mg content of plant tops. The highest and earliest yielding plants were those grown in peat-Turface. The 10-lb. rate of dolomite was essential for high early yields in peat-Turface, but the additional increment of dolomite had no effect on early yields for plants grown in peat-perlite. Interactions existed between media and nutrient levels for growth, nutrient uptake, and early yields.
Automated System for Determining Respiratory Gas Exchange of Plant Materials1
Authors: Dilley David R. , Dewey D. H. , Dedolph R. R.
Published: August 2022

A continuous gas flow system is described which utilizes a paramagnetic O2 analyzer and an infra-red CO2 analyzer to automatically sample, analyze, and record respiratory gas exchange of plant material. The system monitors gas exchange of up to 96 plant samples sequentially, repeatedly, and over extended time periods.
Determination of Need for Potato Irrigation Using Refractometric Index of Sap from Frozen Leaves1
Authors: Ewing E. E. , Farkas L.
Published: August 2022

A modified technique for detecting plant moisture stress through refractometric measurement of expressed cell sap was evaluated for potato, Solarium tuberosum L. The difference between readings of unwatered and watered plants, defined as the Deficiency Index, was used as the basis for determining need for irrigation. The Deficiency Index was found to be greater in young than in old leaves. It reached maximum levels in the late morning and then declined. Irrigation based on the Deficiency Index increased potato yields during 2 of 3 years. Deficiency Indices made before August 5 were negatively correlated with soil moisture block readings, but no correlation was found later in the season. Contrary to earlier reports, the refractometer method does not appear well suited for use by potato growers.
Effects of Ripening Processes on Chemistry of Tomato Volatiles123
Authors: Shah B. M. , Salunkhe D. K. , Olson L. E.
Published: August 2022

Investigations were carried out to isolate, identify, and characterize major volatile components of tomato fruit. Simultaneously, the confirmation was extended to the reported tomato volatiles. The volatile extracts from field and artificially-ripe fruits were compared qualitatively as well as quantitatively. The changes occurring in the volatile components of the fruit at the onset of senescence also were delineated.

A typical chromatogram from field ripe tomatoes contained 60 peaks. The functional group properties of individual peaks were derived by chemical analysis and approximate concentrations of individual groups were calculated. Among alcohols and carbonyls, 3-pen tanol, 1-nonanal, 1-decanal, and 1-dodecanal, and among esters, propyl acetate, geranyl acetate, and citronellyl butyrate were tentatively identified as volatile compounds of tomato fruit. Linalyl acetate, citronellyl butyrate, and geranyl butyrate were identified for the first time as the components of tomato volatiles.

The concentrations of short-chain (C4-C6) compounds were higher in the artificially ripe fruits while the long-chain (C9-C12) carbonyls and the terpene esters were predominant in the field ripe fruits. These differences were discussed. It was indicated that major contributions of the long-chain carbonyls and the terpene esters are essential for ripe tomato aroma. An attempt has been made to theorize the mechanisms of the biogenesis of these compounds. During senescence the amounts of alcohols, aldehydes, ketones, acetates, and propionates generally decreased. However, the concentrations of diacetyl and butyric acid esters increased.
A Study of the Relationship Between Optimum Harvest Dates for Storage and the Respiratory Climacteric Rise in Apple Fruits1
Authors: Blanpied G. D.
Published: August 2022

‘McIntosh’ and ‘Cortland’ fruits were harvested at 3—4 day intervals and ‘Delicious’ and ‘Golden Delicious’ fruits were harvested at 5 day intervals in several seasons. The respiration rate was measured 24 hr after each harvest in order to locate the position of the fruit on the respiratory climacteric curve. The optimum harvest dates for each variety were determined by evaluations of the quality and condition of the fruit after removal from storage. Optimum harvest dates were not found to be associated with any definite position on the climacteric curve.