bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene Introduction to Induce Morphogenesis
Authors: Owens Lowell D. , Cohen Jerry D. , Seelke Ralph
Published: September 2022

In recent years, we have seen the development of many plant cell and tissue culture techniques that, individually or together with recombinant DNA techniques, are being used to modify crops in novel ways. Although these plant biotechnologies may employ a variety of strategies to achieve a particular crop improvement goal, there is one critical element that they all share, the necessity of regenerating a whole plant from a cultured cell, tissue, or organ. Progress has been made in this area with many plant species. For example, reports that were presented at the VI Congress of the International Association of Plant Tissue and Cell Culture (3-8 Aug. 1986) indicate that rice (Oryza sativa L.) now can be routinely regenerated from protoplasts. However, it is still not possible to regenerate plants from protoplasts of most major crops. Included in this list are wheat (Triticum aestivum L.), maize (lea mays L.), barley (Hordeum vulgare L.), oats (Avena sativa L.), and the major grain legume soybean [Glycine max (L.) Merr.]. Our inability to regenerate plants from protoplasts of these crops constitutes a serious block to genetic modification via direct gene transfer techniques. This paper will consider regeneration in the context of soybean, and describe our efforts to devise a genetic, rather than a cultural-physiological solution to the problem.
Mulches and Herbicides in Ornamental Plantings
Authors: Robinson D. W.
Published: September 2022

The present high cost of maintenance is a key factor in every sector of landscape industry. Weed control is a particularly expensive aspect of maintenance and land managers constantly are seeking more effective methods of control. Since soil cultivation is laborious and expensive, herbicides and mulches are becoming popular in many countries. In contrast to herbicides, which have become widely used in ornamentals only in the past 20 years, mulching has been used for centuries.
Field Performance of Osmotically Primed Parsley Seed
Authors: Rabin Jack , Berkowitz Gerald A. , Akers Stuart W.
Published: September 2022

Osmotic priming effects on stand establishment and yield were evaluated for ‘Forest Green’ parsley (Petroselinum crispum Mill.) seed sown on three dates in the field. Stand establishment occurred under progressively higher temperatures for early, middle, and late plantings. Seed priming enhanced early seeded stands 78% at one site and 76% at a second site in comparison with untreated seed. This priming effect on seedling establishment for the earliest planting led to a 67% increase in early yield (96 days from seeding) and a 28% yield increase over untreated seed at a later harvest. Stands of primed seed sown at later dates were enhanced to a lesser extent and yields were not affected by osmotic priming.
Temperature and Photoperiod Effects on Tuber Production and Specific Gravity in Diploid Potatoes
Authors: Haynes K. G. , Haynes F. L. , Swallow W. H.
Published: September 2022

Tuberization response, average number of tubers produced per tuberized plant, total tuber yield, average tuber weight, and average tuber specific gravity were measured for six diploid potato clones grown under long and short day conditions at 22°/18°C and 18°/14° in the phytotron. Average number of tubers and total tuber yield were significantly greater under short days than under long days. Significant temperature × photoperiod interactions were found for these two variables. Lack of significant photoperiod, temperature, and photoperiod × temperature effects on average tuber weight suggests that significant increases in average yield occur due to an increase in the average number of tubers produced and not to an increase in the size of individual tubers. Average tuber specific gravities were significantly greater at 18°/14° than 22°/18°. A significant temperature × photoperiod interaction was found for this variable.
Incorporating Fruit Set Estimates with Thrips Management to Create a Decision Support System for Apples
Authors: DeGrandi-Hoffman Gloria , Terry Irene , Huber Roger T.
Published: September 2022

Control recommendations for western flower thrips (WFT) (Frankliniella occidentalis Pergande) management on apples are combined with fruit set predictions to create the foundation for a decision support system. WFT damage apples during bloom, and population density in positively related to the number of open blossoms. Information concerning bloom stage and fruit set predictions [at time (t)] are helpful for determining when to apply pesticides to most effectively prevent fruit damage. Fruit set predictions also supply information for bee colony removal prior to spray applications if a full crop has been set.
Variability in Flower Bud Number Among Peach and Nectarine Cultivars
Authors: Werner Dennis J. , Mowrey Bruce D. , Chaparro Jose X.
Published: September 2022

Thirty-six peach and nectarine [Prunus persica (L.) Batsch] cultivars were evaluated for flower bud number (flower buds/node) over 2 years. Cultivar, year, and year × cultivar effects were highly significant. Cultivars released from California breeding programs generally had fewer flower buds than those from eastern U.S. programs, suggesting that selection for cropping consistency in eastern breeding programs has resulted in release of cultivars with many flower buds. Variance component estimates from this study and from 2 years of sampling trees of ‘Redhaven’ indicates that sampling over years and increasing the number of shoots sampled per tree is warranted. Variability among trees within cultivar was low.
Various Interstem Effects in Combination with ‘Marubakaido N-1’ Rootstock on ‘Fuji’ Apple Growth
Authors: Koike Hiroo , Tsukahara K.
Published: September 2022

The influence of CG.10, CG.47, CG.80, and M.27 as interstems on ‘Marubakaido N-1’ (Malus prunifolia, var. Ringo) rootstock on growth and yield of ‘Fuji’ apples was evaluated. Trees on M.9 were included as a standard. The order of influence of interstocks from small to large trees was as follows: M.27, CG.80, CG.10, and CG.47. Trees on CG.10/‘Marubakaido N-1’ and CG.80/‘Marubakaido N-1’ were similar in size to those of M.9. Trees on M.9 and CG.10/‘Marubakaido N-1’ produced larger fruit than those on other interstems. Trees on CG.10/‘Marubakaido N-1’ and M.9 were most efficient, followed by M.27/‘Marubakaido N-1’, CG.80/‘Marubakaido N-1’, and CG.47/‘Marubakaido N-1’.
Photoperiodic and Gibberellin-induced Growth and Flowering Responses of Gaillardia × grandiflora
Authors: Evans Michael R. , Lyons Robert E.
Published: September 2022

Gaillardia × grandiflora Van Houtte ‘Dazzler’ and ‘Goblin’ were induced to flower under long days. Applications of GA4+7 (GA) substituted for long days and promoted flowering under short days in the same amount of time required by untreated, photoperiodically induced plants. Although cultivar and photoperiod dependent, GA also increased scape length and reduced scape caliper, flower head diameter and ray floret number. Leaf production was accelerated by several weekly applications of GA.
Water Relations of Cut Eastern Redcedar Christmas Trees
Authors: Hinesley L. Eric
Published: September 2022

Eastern redcedar (Juniperus virginia L.) Christmas trees were cut in early December, brought indoors, and dried to different xylem pressure potentials (Ψ) before the stems were recut and placed in water. Redcedar trees dried rapidly, but quickly rehydrated even at Ψ as low as –6.5 to –7.0 MPa. Trees displayed negligible foliage loss while drying, but those dried to Ψ ≤ –4.9 MPa were predisposed to heavy defoliation following rehydration. There was a linear relationship between Ψ and twig moisture content (dry-weight basis).
Carbon/Nitrogen Ratio and Greening and Protocorm Formation in Orchid Callus Tissues
Authors: Chia T. F. , Hew C. S. , Loh C. S. , Lee Y. K.
Published: September 2022

Callus tissues of orchid Aranda Tay Swee Eng (Archnis Lily Chong × Vanda Piha Moon) were cultured in Vacin and Went's medium that contained between 0% and 2% fructose. The chlorophyll content of callus tissues measured after 31 days of incubation ranged from 59 to 133 µg·g–1 tissue and was inversely proportional to the C/N ratio of the initial culture medium. The number of protocorm developed on callus tissue was instead inversely proportional to the residual C/N ratio of the 31-day-old culture medium and ranged from 13 to 74. The interrelationship of the C/N ratio of the medium, chlorophyll content, and protocorm formation in Aranda callus tissues is discussed.
Complementary Genes for Orange Fruit Flesh Color in Cucurbita pepo
Authors: Paris Harry S.
Published: September 2022

The inheritance of fruit flesh color in Cucurbita pepo L. (squash, pumpkin) was studied in filial and backcross generation progenies of the cross between ‘Vegetable Spaghetti’, which has pale flesh, and ‘Precocious Fordhook Zucchini’, which has orange flesh. Orange flesh was found to be conditioned by two complementary dominant genes, B and L-2.
Two Genes that Induce Brachytic Dwarfism in Peach
Authors: Hansche Paul E.
Published: September 2022

Crosses between brachytic dwarf (dwf) and standard (tall) trees in the peach breeding stock of the Univ. of California at Davis revealed two recessive genes with distinguishable effects on stature. It was concluded that one of these is the Dw/dw gene postulated by Lammerts. This gene was introduced to the United States through PI 41395, ‘Swatow’, in 1915. In homozygotes it effects a reduction in the internode length over that of standard trees from 18 ± 3.1 mm to 7.7 ± 2 mm, which results in 6-year-old trees averaging 1.37 ± 0.25 m in stature at Davis, Calif. The recessive allele, dw2, of the other gene, Dw2/dw2, is hypostatic to the Dw allele of the Dw/dw gene. It was found to be present, but not expressed, in the standard (tall cultivars Kearney, Red Cal, and Fire Red). Doubly recessive homozygotes (of genotype dw/dw, dw/2dw2) have an internode distance of 4.4 ± 0.8 mm and a stature, at 6 years, of 0.92 ± 0.18 m.
In Vitro Growth of American Lotus Embryos
Authors: Kane Michael E. , Sheehan Thomas J. , Ferwerda Feiko H.
Published: September 2022

Rhizome cultures of American lotus [Nelumbo lutea (Willd.) Pers.] were established in vitro from excised embryos cultured in liquid half-strength Murashige and Skoog medium. Effects of medium supplementation with either BA, zeatin, GA3, or ABA on growth and development were evaluated. Neither BA nor zeatin had a significant effect on rhizome growth and development. Maximum rhizome growth and node number occurred in medium supplemented with 290 µm GA3 (100 mg·liter–1). Rhizome growth was inhibited in the presence of 0.38 µm ABA (1.0 mg·liter–1) and greater. Chemical names used: N-(phenylmethyl)-1H-purin-6-amine (BA), 2-methyl-4-(1H-purin-6-ylamino)-2-buten-1-ol (zeatin), (1α, 2β, 4aα, 4bβ, 10β)-2,4a, 7-trihydroxy-1-methyl-8-methylenegibb-3-ene-1, 10-dicarboxylic acid 1,4a-lactone (GA3), [S-(Z,E)]-[5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2,4-pentadienoic acid (ABA).
Enhanced Regeneration in Long-term Callus Cultures of Red Fescue by Pretreatment with Activated Charcoal
Authors: Zaghmout Ousama M. F. , Torello William A.
Published: September 2022

Additions of activated charcoal (AC) to maintenance media before regeneration were evaluted for possible enhancement of plant regeneration from long-term embryogenic callus cultures of red fescue (Festuca rubra L.). Pretreatment with AC increased the level of precocious germination during culture and significantly increased shoot and root formation after transfer to regeneration media. Activated charcoal adsorbed and reduced the activity of toxic levels of 2,4-D. Adsorption of 2,4-D along with other inhibitors of morphogenesis by AC are implicated in the enhancement of regeneration. Chemical names used: (2,4-dichlorophenoxy) acetic acid (2,4-D).
Calculation of Growing Medium Bulk Volume Using Medium Height and Pot Dimensions
Authors: Hershey David R.
Published: September 2022

One of the most important aspects of the physics of growing media in containers is the limited bulk volume of the medium (2,4). Bulk volume (BV) includes the volume of the medium solids and pore spaces (1). Despite the importance of BV in determining the amounts of air, water, and nutrients in the pot, BV is rarely specified in research articles involving plant growth in container media. Without BV, volumetric properties, such as bulk density (g/ml), container capacity (percent by volume), air-filled porosity (percent by volume) and fertilization and liming rates (kg/m3), cannot be converted to absolute amounts per pot. The purpose of this study was to develop equations to calculate BV using pot dimensions and medium height in the pot.
Seven Pea Seedborne Mosaic Virus Resistant Pea Breeding Lines
Authors: Baggett J. R. , Kean D.
Published: September 2022

Seven breeding lines of peas (Pisum sativum L.), OSU 547-29, OSU 559-6, OSU 564-3, OSU 584-16, OSU 589- 12, OSU 615-15, and OSU 620-1, resistant to pea seedborne mosaic virus (PSbMV) and pea enation mosaic virus (PEMV) have been released by the Oregon Agricultural Experiment Station. The lines resulted from three cycles of breeding to transfer pea seedborne mosaic virus resistance from PI lines to commercially usable peas. They have horticultural type approaching that of commercial cultivars, and all have good field resistance to pea enation mosaic virus. The development of cultivars resistant to PSbMV should relieve the pea seed industry of the restrictions and expenses involved in avoidance of PSbMV contamination of seed supplies.
‘Primícia’ Apple
Authors: Denardi F. , Hough L. F. , Camilo A. P.
Published: September 2022

The principal area of apple (Malus domestica Borkh.) production in Brazil is in the south in the states of Santa Catarina, Rio Grande do Sul, and Paraná. In these states, apples are grown using modern technology, and trees are propagated on size-controlling rootstocks (1). Apple production areas are limited because present cultivars have inadequate climatic adaptation and a high level of susceptibility to fungal diseases, including apple scab [Venturia inaequalis (Cke.) Wint.], powdery mildew [Podosphaera leucotricha (Ell. & Ev.) Salm.], and bitter rot [Glomerella cingulata (Ston.) Spauld & Schrenk] (2). There is a need to develop early ripening cultivars that would make it possible to reduce the cost of chemical protection against diseases and also reduce the length of time that late-maturing apples must be stored until the beginning of the next summer's harvest.
Tissue Culture in the Improvement of Eustoma
Authors: Griesbach R. J. , M. Roh P. Semeniuk , Lawson R. H.
Published: September 2022

Genetic engineering offers promise in the development of new plant forms. Alterations in plant size, branching, flower color and form, disease resistance, and many other factors may occur in plants produced by new technologies without sexual breeding and selection. Many desirable characteristics, not always observed in plants developed by breeding, are often expressed in plants engineered by tissue culture technology. Some of the plants showing these different new trait(s) also can be reproduced uniformly from seed, thus indicating genetic transmission of the new trait(s). This exciting approach to plant modification has been used to develop new forms of lisianthus.
Evolution of and Issues Associated with Economically Useful Plastic Greenhouses for Production in the Portuguese Mild Winter
Authors: Monteiro António A. , Lança Cristina , Rosa Armindo , Jordão Antonio , Portas Carlos M.
Published: September 2022

During the past two decades, Europe has seen a marked increase in acreage of vegetables and flowers grown under plastic. The increase in production is most pronounced in the Mediterranean countries, where increased light intensity and favorable winter temperatures made culture under plastic without fossil-fueled heating possible. The migration of the greenhouse industry southward in Europe reflects: a) prohibitive cost of fossil fuels; b) development of simple technologies suitable for small and poorly trained growers; c) decreased investment in structures per square meter and per unit of product produced.
A Review of Taxonomy and Phylogeny of the Genus Lycopersicon
Authors: Warnock S. J.
Published: September 2022

The most recent complete treatments of the genus Lycopersicon were by Muller (17) in 1940 and Luckwill (14) in 1943—these monographs being the first thorough studies since Dunal's (10) treatment in 1852. Muller listed six species for the genus at that time, and three varieties, and three forms within four of these (Table 1). Luckwill (14) was in the course of preparation of his monograph when Muller (17) published his, and, as he indicated, Muller did much to clear up the taxonomic chaos. Luckwill essentially followed Muller in his subgeneric divisions and species treatment, except that Luckwill recognized a seventh species, L. pissisi Phil. (Table 2). In addition, Luckwill attempted to classify, as he indicated, the numerous subspecific and varietal forms, particularly those within L. esculentum Mill. and L. peruvianum (L) Mill., an exercise that Muller avoided.
Citrus Cultivars in Japan
Authors: Iwamasa Masao
Published: September 2022

Total citrus plantings in Japan in 1983 consisted of about 170,000 ha, and the total production was about 3.73 × 106 t. In the past two decades, we have experienced rapid changes in the Japanese citrus industry. Between 1965 and 1975, satsuma (Citrus unshiu Marc.) plantings increased from 115,200 to 169,400 ha, and decreased to 120,700 ha in 1983. Satsuma fruit, which reached a maximum of 3.66 × 106 t in 1975, was overproduced, thus the planting area decreased rapidly, with production diminishing to 2.86 × 106 t by 1983. Plantings of other citrus cultivars increased from 23,800 to 33,900 ha between 1965 and 1975 and to 49,900 ha in 1983. Total production of these cultivars increased from about 308,000 to 872,000 t between 1965 and 1983.
Major Commercial Citrus Varieties of the United States
Authors: Reuther Walter
Published: September 2022

Citrus was introduced to Florida by the early Spanish explorers more than 400 years ago, and to Arizona and California about 200 and Texas about 150 years later by Spanish missionaries. Some of the varieties grown today are selections from seedlings planted by these early Spanish explorers and missionaries. Production was confined largely to local use until the development of effective rail transportation beginning about 100 years ago.
Inducing Flowering of Homalomena lindenii (Rodigas) Ridley with Gibberellic Acid
Authors: Henny R. J.
Published: September 2022

Homalomena lindenii (Rodigas) Ridley treated with a single foliar spray of gibberellic acid (GA3) at 100, 200, or 400 mg·liter–1 flowered within an average of 137 days after treatment whereas untreated plants did not flower. In a second experiment, plants treated with GA3 at 25, 50, 75, or 100 mg·liter–1 did not. Blooms displayed no structural abnormalities.
Influence of Temperature and Controlled Atmosphere on Storage of ‘Green Globe’ Artichoke Buds
Authors: Miccolis Vito , Saltveit Mikal E.
Published: September 2022

Storage of large, mature artichoke buds (Cynara scolymus L., cv. Green Globe) in humidified air at 7°C for 1 week, 2.5° for 2 weeks, or 0° for 3 weeks resulted in significant quality losses. There was little or no beneficial effect of controlled atmosphere (CA) on quality retention when buds were stored at 0° under lowered O2 (1%, 2.5%, or 5%) and elevated CO2 (0%, 2.5%, or 5%) atmospheres. Bracts and receptacles blackened in all treatments after 4 weeks of storage. The degree of blackening was insignificant in air, but became severe as the O2 level decreased from 5% to 1% and CO2 increased from 2.5% to 5%. Thus, CA storage of large artichoke buds can not be recommended.
Cold Hardiness of ‘Midiron’ and ‘Tifgreen’ Bermudagrass
Authors: Anderson Jeffrey A. , Kenna Michael P. , Taliaferro Charles M.
Published: September 2022

Electrolyte leakage and regrowth tests were used to estimate cold hardiness levels of field-grown ‘Midiron’ and ‘Tifgreen’ bermudagrass (Cynodon dactylon × C. transvaalensis crowns. The two procedures were in close agreement. ‘Midiron’ was hardier than ‘Tifgreen’ on all sampling dates. Greatest levels of freeze tolerance were –11°C for ‘Midiron’ and –7° for Tifgreen’ during December and January, ‘Midiron’ was killed at –5° in early June while ‘Tifgreen’ had lost all freeze tolerance by this date. Although the electrolyte leakage procedure was rapid and required no greenhouse space, it was relatively difficult to set up and evaluate.
Selection of Pulp Color and Thickness in Calabaza
Authors: Unander David W. , Varela-Ramirez Felicita
Published: September 2022

Genetic differences in internal color need to be detectable to select improved calabaza [Cucurbita moschata (Duchesne) Poir.] for regions where a dark orange pulp is preferred. For 2 years, data were collected from the cultivar ‘Borinquen’ to relate the effect of age of fruit on internal color. Several possible maturity indicators were also followed. Pulp color was quantified by a color chart assigned numerical values. Orange color increased with fruit age during both years, with a commercially desirable color having developed by 50 days after anthesis in ‘Borinquen’. Maturity indicators, such as dried tendrils or change in rind color, were too variable to be used reliably to choose fruit for detecting pulp color differences among lines. We found tagging of sample fruit at anthesis and harvesting 50 days later to be the most consistent method for selecting lines for orange pulp and/or fast maturation. Using this approach, highly significant differences were found among S1 (self-pollinated) lines for pulp color and thickness and among S2 lines for pulp color. S2 lines were equal or better in pulp color than ‘Borinquen’, even though they were derived from populations variable for pulp traits. Pulp color and thickness were also correlated in these lines. We concluded that both traits seem selectable with our method in early generations of self pollination.
Regeneration of Blueberry Plantlets from Leaf Segments
Authors: Billings Sharon G. , Chin Chee K. , Jelenkovic Gojko
Published: September 2022

A procedure to regenerate shoots in vitro from leaf sections of two blueberry genotypes, ‘Berkeley’ and ‘Bluehaven’, in Woody Plant Medium was established. The effect of 20 combinations of growth regulators: NAA at 0, 1, 2, and 4 µM and 2iP at 0, 5, 10, 15, and 20 µM were compared. Combinations containing NAA generally promoted callus formation and suppressed shoot regeneration. Conversely, media containing cytokinin promoted shoot regeneration and suppressed callus formations. The optimal medium for shoot regeneration contained 15 µM 2iP but no NAA. This procedure was highly efficient (70%–100%) in producing large numbers of shoots in a relatively short period (4 weeks). Chemical names used: N-(3-methyl-2-butenyl)-1-H-purine-6-amine (2iP); 2-(l-naphthyl)acetic acid (NAA).
Immunoblotting to Detect a Soluble Glycoprotein from Trifoliate Orange in a Citrus Hybrid
Authors: Witt Wolfgang , Bausher Michael G. , Yelenosky George
Published: September 2022

Polyclonal antibodies against the major soluble glycoprotein of trifoliate orange [Poncirus trìfoliata (L.) Raf.] were produced in rabbits. The antisera were used to detect the glycoprotein in foliar protein extracts from a hybrid of Poncirus and Citrus genotypes by immunoblotting. One of the sera was found to be highly specific and was suited to indicate trifoliate gene expression. Cross-reacting bands in protein extracts from citrus callus tissue and in the medium of suspension cell cultures suggest that tissue culture systems can be used for biochemical studies of glycoproteins, but not for genotype characterization.
In Vitro Propagation of Kohlrabi from Leaf Explants
Authors: Glendening Thomas M. , Sjolund Richard
Published: September 2022

Tissue culture techniques now are used to propagate species of brassica, many of which are used as vegetables, forage and fodder, and oilseed (2). Tissue culture has been especially beneficial in the maintenance of self-incompatible parent lines of Brassica oleracea and also in eliminating the reduction of vigor associated with continuous inbreeding of parent lines (4). Although many members of B. oleracea have been propagated by tissue culture techniques, the study of the in vitro growth of kohlrabi has been limited (1). In most cases where in vitro growth has been reported, either no plants were regenerated or the regeneration percentage was extremely low (3, 6, 7). We determined the optimum concentration of plant growth regulators needed to induce shoots and to promote their subsequent rooting.
Root Initiation in Root-pruned Hardwoods
Authors: Gilman Edward F. , Yeager Thomas H.
Published: September 2022

Lateral root pruning and rootstock undercutting is practiced in field tree production. The timing, frequency, pruning distance from the trunk, and depth of pruning vary within the industry. Lateral roots formed in response to pruning usually originate close to the cut surface (1, 2, 5). Two recent studies indicated that root pruning field-grown landscape-sized trees increased root density within the root ball (3, 4). This research was conducted to determine the effect of root pruning on the location of regenerated roots and growth of existing unpruned lateral roots.
Growth of Live Oak from Seed Hydrothermally Treated to Control Acorn Weevil Larvae
Authors: Crocker Robert L. , Morgan David L. , Longnecker Michael T.
Published: September 2022

Live oak (Quercus virginiana Mill.) acorns harvested for commercial seedling production frequently are heavily infested by larvae of Curculio spp. (2). Many nurserymen routinely soak acorns for 30 min in 49°C water to kill weevil larvae before planting the seed (4). Microwave radiation is effective against some stored products pests, but it is too damaging for use against acorn weevil larvae (2). Crocker and Morgan (1) measured the short-term (12-day) effects of hydrothermal treatments of tree-harvested acorns on survival of weevil larvae and seed germination, using 0- to 60-min immersion of the seed in 43.3° to 60.0° baths. Treatment for any of the tested times at a minimum of ≈49° controlled 100% of the weevils; it also produced dosage-related plant mortality and reduction in the short-term growth of seedlings. In the present research, we examined the survival and long-term vigor of acorns that were exposed to a 49° hydrothermal treatment.
‘Princesa’ Apple
Authors: Denardi F. , Hough L. F. , Camilo A. P.
Published: September 2022

Production of early ripening apples is becoming important in many areas at intermediate altitudes in southern Brazil, which have a subtropical climate with mild winters (1). However in these areas, winter temperatures only allow cultivation of apple cultivars that require ≈400 hr of chilling at <7.2°C. The cultivars Anna, Ein Shemer, and Vered from Israel, and several local cultivars, such as Rainha, Ohio Beauty, Bruckner do Brasil, and Culinaria, have satisfactory adaptation and are reasonably productive in these areas. With few exceptions, however, the fruit quality is unsatisfactory for Brazilian tastes.
Use of Farming Systems Research Extension (FSR/E) Methods to Identify Horticultural Research Priorities in The Gambia, West Africa
Authors: Gaye G. O. , Jack Isatou , Caldwell John S.
Published: September 2022

In the article “Use of Farming Systems Research Extension (FSR/E) Methods to Identify Horticultural Research Priorities in The Gambia, West Africa”, by G.O. Gaye, Isatou Jack, and John S. Caldwell (HortScience 23(l):21–25, February 1988), the authors wish to make the following acknowledgment: “The work reported herein was done under the Gambia Agricultural Research and Development Project of the Ministry of Agriculture, Government of The Gambia; the United States Agency for International Development; and the Univ. of Wisconsin. We express our appreciation to these institutions for their support.”
Towards a Standardized Nomenclature, Procedures, Values, and Units in Determining Fruit and Nut Tree Yield Performance
Authors: Lombard P. B. , Callan Nancy W. , Dennis F. G. , Looney N. E. , Martin G. C. , Renquist A. R. , Mielke E. A.
Published: September 2022

Flowering, fruit set, fruit size, and bearing potential are the main components of tree fruit and nut yield. The contributions of the individual components to yield and their interrelationships must be clearly defined in research addressing tree fruit productivity. Researchers have been inconsistent in terminology and procedures used to evaluate treatment effects on the major yield components. Although the relative effect of a treatment may be evident within an individual study, standardized measuring and reporting procedures are necessary if one wishes to compare results within the same species from various investigators, locations, and disciplines.
Fungal-induced Blemishes of Snap Peas Associated with Adherence of Blossom Parts to the Pods
Authors: Dillard Helene R. , Hunter James E.
Published: September 2022

Snap peas (Pisum sativum L.) grown under the humid conditions of New York State often retain blossom parts on the pods. Blemishes caused by several fungi (Alternaria, Ascochyta, and Penicillium species) that developed on these blossom parts resulted in the pods being unmarketable. Symptoms included punctate lesions and protuberances that formed a rough surface on the pods. Affected areas exhibited reddish-brown to black discoloration. Commercial production of snap peas may not be successful in warm, humid regions until cultivars are developed that release blossom parts following anthesis.
Sooty Mold Fungus on Pecan Foliage Suppresses Light Penetration and Net Photosynthesis
Authors: Wood Bruce W. , Tedders Walker L. , Reilly Charles C.
Published: September 2022

The heavy levels of sooty mold commonly present on pecan [Carya illinoensis (Wangenh.) C. Koch] foliage in the autumn prompted an evaluation of its influence on net photosynthesis (Pn) of pecan leaves. Extra heavy sooty mold levels were observed to block light penetration to the leaf surface by up to 98%. Heavy mold levels suppressed leaflet Pn by up to 70% with suppression due to a blockage of photosynthetically active radiation (PAR). An observed 4°C increase in abaxial leaf surface temperature may also contribute to this suppression. The results indicate a possible need to introduce sooty mold control methods into orchard management programs.
Rapid Determination of Urea Hydrolysis and Nitrification in Potting Media
Authors: Elliott George C.
Published: September 2022

Rapid assays for urea hydrolysis and for the oxidation of NH4+ to NO2– and NO3– are required for extensive studies of these processes in potting media. Methods originally developed for use with field soils were evaluated and modified for use with soilless media. Effects of urea concentration, buffer pH, and incubation temperature on rates of urea hydrolysis were tested with two media. Response to these variable was less pronounced in soilless potting media than in field soils. Urea hydrolysis can be conveniently assayed in soilless media under the following conditions: 5 mol urea/m3 medium, Tris buffer pH 8.0, 37°C. Rates of NH4+ and NO2– oxidation were estimated from the accumulation of NO2– in samples incubated for 0 to 24 hr with 4 mol NH4+/m3 medium as substrate in 1.0 mM phosphate buffer, pH 7.0, with or without 20 mol NaClO3/m3 medium. The rate of NO2– accumulation in the presence of ClO3–, an inhibitor of NO2– oxidation, estimates NH4+ oxidation, and the slope of the difference in NO2– between samples with and without ClO3– estimates the rate of NO2– oxidation. Although ClO3– does not completely inhibit NO2– oxidation in one of the two media tested, the method is useful for comparison of nitrification activity in potting media.
Alleviation of Chilling Injury in Papayas
Authors: Chan Harvey T.
Published: September 2022

Susceptibility to chilling injury in ‘Kapoho’ papayas (Carica papaya L.) was reduced by ripening the fruit before storage at 5°C. The relationship between the decrease in chilling injury (CI) and postharvest ripening time at 24° was found to follow first order kinetics, hence, the half-lives for reducing the symptoms of CI of scald and hard core are 14.8 and 33.5 hr, respectively.
Plant-Water Relations of Young Highbush Blueberry Plants
Authors: Byers Patrick L. , Moore James N. , Scott H. Don
Published: September 2022

Diurnal and seasonal measurements of leaf water potential (ψ1), leaf diffusive resistance (R1), and leaf stomatal conductance (gs) of highbush blueberry (Vaccinium corymbosum L. cv. Bluecrop) were made in 1984 and 1985. Marked diurnal variation in ψ1, R1, and gs was observed. The most negative values of ψ1 were usually reached by 1000 Central Standard Time and were maintained until late afternoon. Leaf stomatal conductance values were high in early morning, remained high throughout the day, and decreased in late evening. Stomata were absent on the adaxial leaf surface, while the abaxial surface averaged 553 stomata/mm2. Unexplained seasonal changes in ψ1 and R1 were noted in 1985. Leaf water potential and R1 were significantly correlated in one year. Leaf water potential and R1 were significantly correlated with air temperature and relative humidity, respectively, in both years.
Diurnal Temperature Cycling Influences Flowering and Node Numbers of Broccoli
Authors: Miller Conrad H.
Published: September 2022

Broccoli plants (Brassica oleracea L. var. italica) were subjected to two diurnal chilling temperature cycles that varied between 2° and 14°C and from 14 to 52 days. Cycles differed in the length of time in transition between the minimum and maximum temperatures. In two experiments, plants were grown in an air-conditioned greenhouse phytotron at 22°/18° (day/night temperature) for 7 to 21 days before chilling. Plants (and germinating seeds) placed in the chilling environment for 28 to 49 days from 0 to 21 days from seeding, flowered as much as 13 days earlier than plants not chilled. Further, plants 14 days from seeding and chilled for an additional 28 days flowered 16 days earlier than controls. Similarly, chilled plants had fewer nodes at flowering attributable to the temperature cycling regimes, except in a third experiment when seeds in pots were placed immediately into the chilling cycles for 31 to 52 days. ‘Futura’ flowered earlier than ‘Early One’ but neither was different from ‘Bravo’ or ‘Apollo’ in this third experiment.
Effects of Starchy Sugary-2 and Sugary Sugary-2 Endosperm on Pericarp Thickness in Sweet Corn
Authors: Schmidt D. H. , Tracy W. F.
Published: September 2022

The thickness of the pericarp is one of the most important factors determining quality in sweet corn (Zea mays L). A study was conducted to determine if differences observed in pericarp thickness between kernels with starchy sugary-2 (Su su2) and sugary sugary-2 (su su2) endosperm types were due to linkage effects or endosperm genotype effects. Reciprocal crosses were made between near-isogenic lines with Su su2 and su su2 endosperm types in four inbred backgrounds. The F1 plants were self-pollinated and ears segregating at the sugary locus were analyzed for pericarp thickness. The pericarp is maternal tissue, therefore all kernels from an ear have the same genotype regardless of the endosperm genotype. Highly significant effects (p ≤ 0.01) for pericarp thickness were found for endosperm, inbred, and endosperm by inbred interactions. If differences between Su su2 and su su2 endosperms were due to linkage effects, endosperm type would not have been significant. Endosperm type Su su2 had thicker pericarp than su su2 in all inbred backgrounds, but differences were significant in only two of the four backgrounds. Averaged over four inbred backgrounds, the pericarp thickness of Su su2 kernels and of su su2 kernels was 45 and 35 µm, respectively. A difference of this magnitude might be detectable as a difference in sweet corn tenderness.
Embryo Culture as a Means of Introgressing Seedlessness from Vitis vinifera to V. rotundifolia
Authors: Goldy Ron , Emershad Richard , Ramming David , Chaparro Jose
Published: September 2022

Embryos from five seedless Vitis vinifera L. clones were cultured in ovulo 6 weeks after pollination with V. rotundifolia Michx. A total of 19 hybrid seedlings from about 16,000 pollinations were identified using leaf morphology and starch-gel electrophoresis. Efforts to obtain more V. vinifera/V. rotundifolia hybrids carrying the seedless gene(s) using embryo rescue should be increased and these plants could act as breeding stock to introduce the seedless gene(s) from V. vinifera into V. rotundifolia.
Seasonal Variation of Leaves and Mite Resistance of Lycopersicon Interspecific Hybrids
Authors: Good Donald E. , Snyder John C.
Published: September 2022

Clones of 10 F2 mite-susceptible Lycopersicon esculentum Mill. × mite-resistant L. hirsutum Humb. & Bonpl. were raised in summer and winter in the greenhouse. Leaflets from clones grown in both seasons were assayed for two-spotted spider mite survival (Tetranychus urticae Koch); Type IV, Type V, and Type VI trichome densities; and zingiberene and γ elemene concentrations. Clone, season, and their interaction were significant sources of variance of all six variables. Between season, among clones, and among clones between seasons, mite survival was inversely correlated with Type IV trichome density. No evidence for involvement of sesquiterpene presence or concentration or Type V or Type VI densities with mite survival was observed. Covariance analysis of mite survival using Type IV trichome density as the covariable removed the significance of the clone × season interaction, reduced the significance level of clonal variation, and reduced the mean square of seasonal variation. Because Type IV trichome density and mite survival were related across all sources of variation, Type IV trichome density is probably mechanistically and causally related with host-plant resistance of Lycopersicon hirsutum to mites.
An Improved Technique for Counting Chromosomes in Grapes
Authors: Martens Mary-Howell R. , Reisch Bruce I.
Published: September 2022

Various procedures were compared to identify a technique that would produce clear countable chromosomes in grape (Vitis L.) root tip squashes. Harvesting roots at 1100 hr from greenhouse-grown plants, pretreating with 0.02 m 8-hydroxyquinoline at 18°C for 6 hr, fixing in Farmer's Fluid at 26° for 24 hr, hydrolyzing in 1 n HCl at 60° for 1 hr, and staining with an altered form of carbol fuchsin gave the best results.
Computerized Individual-nutrient Fertilizer Injector: The System
Authors: Bauerle W. , Short T. , Mora E. , Hoffman S. , Nantais T.
Published: September 2022

The Ohio State Univ. Computerized Individual-nutrient Fertilizer Injection System is being developed to give greenhouse growers the ability to control precisely the concentration of individual nutrients delivered to plants (Fig. 1). This system allows for changes of individual nutrients as dictated by growing conditions.
Fabric Plant Covers as an Aid in Muskmelon Breeding
Authors: Ng Timothy J
Published: September 2022

Muskmelon (Cucumis melo L.) plants primarily are pollinated by honey bees (5) and naturally pollinated fruits contain highly varying percentages of self-pollinated seed (3, 8). Muskmelon breeders often rely on controlled hand pollinations for making out-crosses and self-pollinations in the field; natural pollinators must be excluded from perfect or pistillate flowers until fruit set has occurred. If fruits are set from natural pollination, they often are removed since the presence of fruits on a plant may suppress subsequent fruit set (4).
Hibiscus Freezing Tolerance
Authors: Teets Thomas M. , Hummel Rita L.
Published: September 2022

The objective of this research was to identify cold hardiness levels of some Hibiscus species in response to natural environmental conditions in Gainesville, Fla. by determining the lowest survival temperature (LST) in laboratory tests.
‘Southern Blush’ Anthurium
Authors: Henny R. J. , Poole R. T. , Conover C. A.
Published: September 2022

Many cultivars of Anthurium andraeanum are grown for production of cut flowers because of their large and showy spathes, which occur in shades of red, orange, pink, or white. Most A. andraeanum have been bred for large spathes, which may reach 0.25 m in length and 0.16 m in width. However, their long petioles and large leaves are not in good proportion for growing as a pot plant. Since A. andraeanum can be grown under the same cultural conditions as ornamental foliage plants, attempts were made to produce hybrids suitable for use as potted ‘flowering’ foliage plants.
‘Aross Central Park’ Chinese Elm
Authors: Karnosky David F.
Published: September 2022

Chinese elm (Ulmus parvifolia Jacq.) is an attractive, medium-sized ornamental tree with excellent urban-hardiness and pest resistance. Introduced into cultivation in the late 1700s, this species is commonly grown in parks, lawns, and streetside locations in the southern United States and California. There have been only three Chinese elm cultivars selected in this country (1, 2). Nurserymen have expressed their desire to find a Chinese elm with an increased level of cold hardiness so that the species could be used in cities in the northern United States. The ‘Aross Central Park’ Chinese elm is cold hardy to zone 6 (Arnold Arboretum hardiness zones) and will grow in protected areas in zone 5. Thus, it is the most cold hardy Chinese elm available.
‘Ohio 8243’ Processing Tomato
Authors: Berry Stanley Z. , Gould Wilbur A.
Published: September 2022

‘Ohio 8243’ is a main season tomato (Lycopersicon esculentum Mill.) adapted for machine harvest and bulk handling and exhibits processing quality especially suitable for the production of peeled, coreless whole-canned tomatoes (whole-pack), as well as for juice and sauce. Extensive test acreages have been grown by the mid-western and eastern U.S. and Canadian tomato processing industries. The new cultivar has been well received by growers and processors and its use is increasing.
Sensitivity of Seed Germination of Amaryllis to Light and Temperature
Authors: Carpenter William J. , Ostmark Eric R.
Published: September 2022

Amaryllis, (Hippeastrum × hybridum Hort.) seed germination was light-independent, but temperature influenced the germination rate. Constant 25°C promoted higher total germination (86%), fewer days (8.3) to germinate, and a shorter span of days (4.3) than other constant temperatures or alternating temperatures of 25°–30°, 20°–30°, 15°–25°, 25°–35°, or 15°–35°. Exposures to 10° or 40° for 1 to 3 days during various seed germination phases reduced germination by 14% to 23% and delayed radicle emergence, but 40° for 1 to 3 days caused larger reductions in germination than comparable durations at 10°. Exposure of seeds to 10° or 40° between days 2 and 4 caused the largest reductions in total germination.
Comparison of Paclobutrazol Tablets, Drenches, Gels, Capsules, and Sprays on Chrysanthemum Growth
Authors: Sanderson Kennath C. , Martin Willis C. , McGuire John
Published: September 2022

Paclobutrazol drenches were more effective in retarding chrysanthemum (Chrysanthemum × morifolium ‘Charm’) plant height than paclobutrazol incorporated in plaster-of-paris tablets, injected hydrogels, and gelatin capsules applied at the same rate (0.5 mg a.i./15-cm pot) in three experiments. Capsules containing paclobutrazol also controlled plant height effectively in all three experiments. Drenches consistently reduced plant area, whereas a 50-ppm paclobutrazol spray did not. Paclobutrazol tablets, gels, and capsules reduced plant area in two of three experiments. Drenches were the only treatment to reduce flower number per plant. Chemical name used: β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).
Application of Poultry Manure Influences Thompson Seedless Grape Production and Soil Properties
Authors: Bhangoo Mahendra S. , Day Kenneth S. , Sudanagunta Venkateswara R. , Petrucci Vincent E.
Published: September 2022

Raw and composted poultry manure application rates of 0, 4.5, and 9.0 t·ha–1 in a ‘Thompson Seedless’ grape (Vitis vinifera S.) vineyard on a Ramona sandy loam (Typic Haploxeralfs) were studied for 3 years (1984–1986). Manure was side-dressed on both sides of vine rows and incorporated in the top 0.1 m of soil in November each year. Petioles of the recently matured leaves at bloom, veraison, and maturity were taken (1985–1986) for NO3-N, P, and K determination. Soil samples to 0.3 m depth were taken in 1986 to evaluate soil properties. Fruit yield and quality increased over the control with manure applications. The response to the 4.5 and 9.0 t·ha–1 rates was similar. In 1985 and 1986 berry yield increased 26% and 61%, respectively, over the control. Berry size (1986), cluster numbers per vine (1985–1986), and cluster weight (1986) increased with applied manure. Raisin quality in 1986 improved linearly (r = 0.93) with manure rates. Petiole NO3-N (1984–1986), P, and K contents (1986) increased with applied manure over the control. Soil pH decreased with the 9.0 t·ha–1 rate. Soil available P, exchangeable K, NO3-N, and organic matter content and water infiltration rate increased with manure application. Manure at 4.5 t·ha–1 was as effective as 9.0 t·ha–1 in increasing fruit yield and quality. Manure type was not a significant factor.
K and N Fertilization Rates Influence Susceptibility of Trickle-irrigated Tomato Plants to Bacterial Spot
Authors: Jones J. B. , Stanley C. D. , Csizinszky A. A. , Kovach S. P. , McGuire R. G.
Published: September 2022

Field studies were conducted over three seasons to determine the effect of N and K on susceptibility of tomato to bacterial spot. A factorial randomized complete block design consisting of four rates of N (167, 334, 501, and 668 kg·ha–1) and three rates of K (334, 668, and 1335 kg·ha–1) were used. Liquid fertilizer was injected via trickle irrigation. Increasing N rates reduced disease severity, whereas the effect of increasing K was inconsistent from season to season. The concentration of N in leaf tissue showed a significant negative correlation with disease severity, whereas the concentration of Ca in leaf tissue exhibited significant positive correlation with disease severity and negative correlation with N rate during two seasons of data collection.
Influence of pH on Cadmium and Zinc Concentrations of Cucumber Grown in Sewage Sludge
Authors: Falahi-Ardakani Ali , Corey Kenneth A. , Gouin Francis R.
Published: September 2022

Parthenocarpic cucumber (Cucumis sativus L. ‘La Reine’) plants were grown in the greenhouse in containers filled with equal parts by volume of peatmoss and vermiculite blended with 0%, 25%, or 50% by volume compost made from ferric-chloride-precipitated, lime-stabilized, digested sewage sludge composted with wood-chips and amended with various rates of sulfur. The Cd concentration of leaf and fruit samples from plants grown in media amended with 25% or 50% compost and S at 0, 10, 20, or 40 g·liter–1 was unaffected by changes in pH from 7.2 to 3.4. However, Zn concentration in fruit samples from plants grown in media amended with 25% compost and S at 40 g·liter–1 increased relative to other rates of S, whereas Zn concentration of leaf tissue was unaffected by rate of S application. Yield of fruit was not significantly affected by any of the treatments. Cucumber plants can be grown successfully in media amended with as much as 50% composted sewage sludge low in heavy metal content and over a wide range of pH values without the accumulation of fruit Cd levels hazardous to human health.