bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Influencing Flower Petal Abscission in the Seed-propagated Geranium1
Authors: Armitage A. M. , Heins R. , Dean S. , Carlson W.
Published: August 2022

Flower petal abscission (shattering) in seed geraniums (Pelargonium X hortorum Bailey) is delayed by low temperature (1-5°C) and ethylene-free air. Naphthaleneacetic acid (NAA) or CO2 (5%) did not delay shattering. Respiration and endogenous ethylene synthesis did not follow a climacteric pattern. A method was devised to test flowers for petal abscission. Variation in petal abscission was found among flowers of 35 cultivars evaluated over a 2-year period.
Root Distribution of ‘Coville’ and ‘Lateblue’ Highbush Blueberry under Sawdust Mulch1
Authors: Gough R. E.
Published: August 2022

The root system of the cultivated highbush blueberry (Vaccinium corymbosum L.) is primarily composed of fine, thread-like roots less than 1 mm in diameter. Essentially all of the roots of 7-year-old ‘Lateblue’ bushes were located within the area between the crown and the dripline. Most of the roots on 13-year-old ‘Coville’ bushes were also within this area. Roots were found 180 cm from the crown and at depths of 81 cm. Roots were in the decomposing low layers of the sawdust mulch but not within the upper, non-decomposing layers.
Carnation Production Responses to Solar Radiation Transmitted through Plastic Greenhouse Covers1
Authors: Sherry William J. , Goldsberry Kenneth L.
Published: August 2022

Dianthus caryophyllus L. cvs. DWF White #1, Scania and Crowley's Pink Sim were grown in greenhouses covered with new corrugated fiberglass reinforced plastic panels (New FRP), single layer UV-resistant polyethylene (Sgl Poly), air inflated double layer polyethylene (Dbl Poly), and 8-year-old weathered corrugated fiberglass reinforced plastic panels (Old FRP). Total flower production in the New FRP, Dbl Poly and Old FRP cover treatments was 1.9, 21.8 and 56.5% less, respectively, than in the Sgl Poly treatment. Significant interactions were noted between cultivar fresh weights, stem lengths, grades and cover treatment. Increase of irradiance in the cover treatments reduced return crop times while increasing stem length, fresh weight and grade.
Daylength and Temperature Effects on Days to Flowering of Early and Late Maturing Beans (Phaseolus vulgaris L.)1
Authors: Wallace D. H. , Enriquez G. A.
Published: August 2022

Starting from daylength (DL) × temperature (T) environments combining short or intermediate DL with low or intermediate T, days to first flower (FF) of beans was progressively decreased as the duration of T was extended and/or as T was raised to intermediate levels. This universal temperature response caused 13 to 22 day decreases, under both 3° and 6°C night temperature/day temperature (NT/DT) difference, for both early and late maturing lines. The decrease in days to FF that appeared to result from extending DL was due to the attendant and simultaneous extending of the duration of DT and decreasing of the duration of NT. Starting from environments combining intermediate to longest DLs with intermediate to highest Ts, which environments had the fewest days to FF, on the contrary, increases in days to FF occurred as DL was further extended and/or as T was further raised. This photoperiod-temperature response (Pp-T response) caused 2 to 5 day increases in days to FF for early-maturing photoperiod-insensitive lines, and 10 fold larger increases of 40 to 53 days for late-maturing, photoperiod-sensitive lines. The gene(s) conditioning the late-maturing, photoperiod-sensitive phenotype, therefore, caused a 10-fold increase in the days of delay to FF, i.e. of a Pp-T response that is weakly expressed in the early-maturing photoperiod-insensitive genotype. The Pp-T responses of the photoperiod insensitive and sensitive genotypes were both half as large, 0 to 4 and 17 to 29 days, respectively, when the NT/DT difference was 3° rather than 6°C; there was also a requirement for a higher T to activate the Pp-T response. This commonly called photoperiod response, was called the Pp-T response because it was altered as much by T as by DL.
Fruit and Leaf Isozymes as Genetic Markers in Avocado1
Authors: Torres Andrew M. , Bergh B. O.
Published: August 2022

Leaf samples of over 100 avocado (Persea americana Mill.) cultivars and 8 other Persea species were analyzed for isozyme variation of peroxidase (PX), malate dehydrogenase (MDH), leucine aminopeptidase (LAP) and phosphoglucose mutase (PGM). MDH, LAP and PGM isozymes of leaf and mesocarp were identical. Isozymes of alcohol dehydrogenase (ADH) and glutamate oxaloacetate transaminase (GOT) were detected in mesocarps but were not available from leaves. Leaf PX isozymes were specified by 3 genes having 11 alleles and MDH isozymes by 1 gene with 3 alleles. To date, 6 enzyme systems specified by 12 genes with 37 codominant alleles are available as genetic markers of possible use in problems of avocado systematics, measurements of outcrossing rates, documentation of parentages and screening of seedlings in breeding programs.
Calcium Oxalate Crystals in the Roots of Sweet Potato1
Authors: Schadel W. E. , Walter W. M.
Published: August 2022

Druse crystals observed with light and scanning electron microscopy in root tissue of Ipomoea batatas (L.) Lam. cv. Jewel were identified as calcium oxalate monohydrate by use of energy-dispersive X-ray analysis and X-ray diffraction techniques. Crystals occurred primarily in the parenchyma cells of the edible root.
Polyethylene Glycol Induced Water Stress Effects on Apple Seedlings. I. Methodology, Water Consumption, and Dry Matter Production1
Authors: Gergely I. , Korcak R. F. , Faust M.
Published: August 2022

Apple seedlings (Malus domestica Borkh.) were grown in the greenhouse under a range of polyethylene glycol (PEG)-induced osmotic potential stresses up to −7.5 bars. Water use by seedlings (ml water consumed/dm2 leaf area) responded to ambient temperature fluctuations after 4 days in the solution. During the first 4 days after initiation of the stress, no response was obtained indicating that the seedlings were undergoing an “adaptation period.” Plants receiving higher osmotic stresses were less able to respond to ambient temperature fluctuations as measured by transpiration. Transpiration rate decreased as osmotic stress was increased. PEG-induced osmotic water stress and water stress in soil were compared, the latter by letting the soil mass dry out. Comparable transpiration rates from the 2 methods, when plotted, showed that PEG-induced osmotic stresses of −0.5 and −4.0 bar were equivalent to greenhouse potting soil at 75% of field capacity and approaching the wilting point, respectively. It was concluded that the PEG-induced water stress was similar to water stress in soil, thus PEG-induced stress can be used in experiments with apples to study various effects of water stress. Use of a freezing point depression osmometer in determining solution osmotic potentials of PEG-modified solutions is described.
Effect of Plant Age on Callus Growth, Plant Regeneration, and Anther Culture of Geranium1
Authors: Hammerschlag F. , Bottino P.
Published: August 2022

Callus cultures from 2-week, 2-month, and 2-year-old Pelargonium × hortorum Bailey cv. Sprinter on modified Linsmaier and Skoog medium supplemented with various concentrations of α-naphthaleneacetic acid (NAA) and 6-furfurylaminopurine (kinetin), while anthers from 2-month and 2-year old plants were cultured on a separate medium. Fresh weight increases of callus which were measured 1, 2, and 3 weeks after plating stem explants were ×13.4, ×22.9, and ×39.0 for 2-week-old seedlings; ×4.8, ×7.1, and ×l9.0 for 2-month old plants; and ×3.5, 5.9, and ×19.5 for 2-year-old plants. Only callus from explants of 2-week-old seedlings regenerated shoots and roots after 6-8 weeks on medium containing 0.2 mg/liter NAA and 2.0 mg/liter kinetin. An average of 11.2% of ‘Sprinter’ anthers from flowers on 2-month-old plants yielded callus, whereas only 2% of anthers from 2-year-old plants yielded callus.
Effects of Low Temperature, Cooling Rate, and Moisture Content on Seed Germination of Lettuce1
Authors: Roos Eric E. , Stanwood Phillip C.
Published: August 2022

Seeds of 5 cultivars of lettuce (Lactuca sativa L.) were adjusted to moisture contents between 5 and 22% and subjected to temperatures of 5, -18, -70, and -196°C (liquid nitrogen) for 7 days. Seeds with moisture contents up to 18% were not damaged by either -18 or -196°C; however, the -70°C treatment resulted in loss of germination even with seeds containing as little as 16% moisture. Seeds held at 5°C showed no loss in viability. The loss in germination at -70°C appeared to be related to cooling rate. High moisture (18 to 20%) seeds were cooled to -196°C at different rates from 1 to 200°C/min. Germination was reduced in seeds cooled at rates slower than 25°C/min. At 200°C/min cooling rate and 18 to 20% seed moisture both germination and root growth occurred although at reduced levels compared with control seeds held at 5°C. Prolonged storage (33 days) in liquid nitrogen of rapidly frozen high moisture lettuce seeds did not result in further loss of germination after the initial freezing to -196°C.
Softening and Ripening of ‘d’Anjou’ Pears as Influenced by Simulated Transit Temperatures1
Authors: Mellenthin W. M. , Chen P. M.
Published: August 2022

‘d’Anjou’ pears (Pyrus communis L.) harvested at optimum maturity with flesh firmness of 6.4 kg were stored at -1.1°C for 3 months before being subjected to different intermittent and simulated transit temperatures. Fruit held for 3 days at 1.7 or 7.2°C did not soften significantly at transit temperature of -1.1°C for 4 weeks, whereas fruit held for 3 days at 12.8°C softened from 6.0 kg to 4.0 kg after 4 weeks at -1.1°C. After 4 weeks at 1.7°C, fruit held for 3 days at all intermittent temperatures softened 5.0-3.5 kg. Simulated transit temperatures above 7.2°C caused softening to less than 2.5 kg within 3 weeks. The additive effects of brief intermittent and 4-week simulated transit temperatures indicated that the higher the temperature, the more softening of ‘d’Anjou’ pears occurred. Fruit held for 3 days at 1.7, 7.2, or 12.8°C and 4 weeks at -1.1 or 1.7°C softened rapidly to 1 kg within 8 days in the ripening environment at 20°C, in conjunction with accelerated rates of respiration and ethylene production. However, softening preceded climacteric rises in ethylene and respiration of fruit kept 4 weeks at -1.1°C.
Ethylene Production by ‘Valencia’ Peel Explants Treated with Abscission-accelerating Compounds1
Authors: Evensen Kathleen B. , Bausher Michael G. , Biggs R. Hilton
Published: August 2022

Ethylene production in peel explants of ‘Valencia’ oranges [Citrus sinensis (L.) Osbeck] treated with 5-chloro-3-methyl-4-nitro-1H-pyrazole (Release) was similar in pattern to ethylene production by whole fruits treated with the chemical. Smaller amounts of ethylene were produced by untreated peel explants. Explants from fruit harvested in October and March showed similar patterns of ethylene evolution when untreated and when Release was applied. The response to this chemical was localized in the flavedo. Ethylene production was dependent on temperature in both untreated and Release-treated peel explants, but the ethylene response to the chemical was particularly temperature-dependent. The temperature optimum in both cases was approximately 25°C. Peel disks from regreening fruit generally produced less ethylene than disks from nongreening fruit when Release or glyoxal dioxime (ethanedial dioxime, Pik-Off) was applied. The magnitude of the difference between regreening and nonregreening disks depended on the concentrations of Pik-Off or Release applied.
Alteration of Sex Expression in Cucumber Due to Changes in Temperature, Light Intensity, and Photoperiod1
Authors: Cantliffe Daniel J.
Published: August 2022

Five pickling cultivars and a breeding line of cucumber (Cucumis sativus L.) were grown under varying environmental conditions to determine the influence of light and temperature on sex expression. More staminate flowers were produced under 17,200 lux light intensity than 8,600,12,900 or 25,800 lux, whereas more pistillate flowers reached anthesis under the highest 2 light intensities. A gynoecious line, MSU 713-5, produced no staminate flowers under varying light intensities, however gynoecious hybrids did. Altering the length of the photoperiod or red and tarred light exposure at the end of the light period had no influence on sex expression. Few staminate flowers were produced when the plants were grown at a constant 16° or 22°C, but all lines or cultivars produced some staminate flowers at 30°. The largest number of pistillate flowers reached anthesis at 26° or 30°. Temperature influenced sex expression more than light intensity or photoperiod.
Preplant Tillage, Soil Strength, and Root Growth of Turnip Greens1
Authors: Phatak S. C. , Threadgill E. D. , Glaze N. C. , Dowler C. C.
Published: August 2022

Disc tillage of turnip greens (Brassica campestris L. Rapifera group) caused an abrupt increase in soil strength below tillage depth, which in turn prevented turnip root penetration. Soil strength of 85 N/cm2 on Lakeland sand and 100 N/cm2 on Tifton sandy loam prevented penetration of turnip roots. In general, root fresh and dry weights were unaffected by tillage treatments. Turnip root growth with the disc treatment was shallow, whereas turnips grown with subsoil-bed and subsoil-plant tillages developed deeper root systems. Balanced downward and horizontal turnip root systems were developed with mold-board plow preplant tillage.
Effect of Irrigation and Tree Density on Peach Production1
Authors: Layne R. E. C. , Tan C. S. , Fulton J. M.
Published: August 2022

An experimental peach (Prunus persica [L.] Batsch cv. Harken/Siberian C) orchard was planted on Fox sand in 1973 at 266, 358 and 536 trees/ha. The plots were either not irrigated or irrigated at a frequency necessary to prevent the available soil moisture (ASM) from falling below 25 or 50%. Irrigation stimulated tree growth in the earlier but not in the later years of the experiment. Growth was reduced by an increase in tree density especially in the later years at the highest density. Only in 50% ASM plots was growth not affected by high tree density. Irrigation (50% ASM) increased cumulative, marketable yields in the first 5 years of production by up to 9.7% while tree density (536 trees/ha) increased similar yields by up to 74.6% without irrigation and up to 99.5% with irrigation (50% ASM + 536 tree/ha). Irrigation consistently improved the proportion of large and medium-sized fruit while reducing the proportion of small, unmarketable fruit. Tree density had a smaller and less consistent influence on fruit size. Neither irrigation nor tree density adversely affected split pits, raw product fruit quality, cold hardiness or canker (Leucostoma spp.) susceptiblity. There were no significant interactions of irrigation and density treatments in any year, indicating that each treatment might be used to advantage without adversely affecting the other, at least in the first 7 years of growth and first 5 years of production.
Sensitivity of Pregerminated Pepper Seed to Low Temperatures1
Authors: Cayer Irwin Christine , Price Hugh C.
Published: August 2022

The effect of storage of pregerminated pepper seed (Capsicum annuum L. cv. Hungarian Wax)at 0°C for 2 to 4 days and 5° for 4 to 21 days on total percent emergence, time to 50% emergence (T50), and tissue viability was examined. An emergence assay at 25°×20° showed that only dry seed and seed held at 0°C for 4 days were slower in emerging than fresh pregerminated seed. Emergence assays at 15°×10° showed that all storage treatments except 5° for 4 days resulted in slower seedling emergence. Dry seed took twice as long to emerge as fresh pregerminated seed at 15°×10°. Percent emergence data and tetrazolium chloride assay results supported the T50 data.
Terrestrial Orchid Seed Germination in Vitro on a Defined Medium1
Authors: Henrich James E. , Stimart Dennis P. , Ascher Peter D.
Published: August 2022

Seeds of 29 terrestrial orchid species representing 15 genera were surface sterilized by immersion in 0.5% sodium hypochlorite containing a wetting agent, washed, sown on a completely defined, semisolid embryo culture medium containing macro- and microelements, sucrose, amino acids, and vitamins, and incubated in the dark at 25°C. Six months after sowing, 16 species from 9 genera germinated and continued development while 13 species from 10 genera failed to germinate. Species of Cypripedium, Goodyera, Platanthera and Spiranthes differed in response in that one or more of each germinated and one or more did not. Seedling development was similar for most germinating species and progressed to the formation of a shoot or shoot initial in all but one. Apparently the mycorrhizal association thought to be required for terrestrial orchid seed germination and early seedling development can be replaced with aseptic culture on a completely defined medium for many terrestrial orchids.
Impact-induced Breakdown in Commercially Screened ‘Howes’ Cranberries1
Authors: Massey L. M. , Chase B. R. , Starr M. S.
Published: August 2022

Physiological breakdown resulting from impacts due to rough handling occurs following commercial screening of fresh market ‘Howes’ cranberries (Vaccinium macrocarpon Ait. cv. Howes.) Development of visible defects from impacted berries frequently involves a lag period of several hours and significant breakdown can occur in impacted berries showing no visible defects as long as 24 hours following impacts.
Agents Influencing Russet on ‘Golden Delicious’ Apple Fruits1
Authors: Creasy L. L. , Swartz H. J.
Published: August 2022

Russet on ‘Golden Delicious’ apple (Malus domestica Borkh.) was induced by sprays of butanedioic acid mono-(2,2-dimethylhydrazide) (daminozide), Diazinon, superior oil, and by environmental factors. Russet severity was reduced by application of a silicon dioxide formulation and by protecting fruit from environmental conditions by bagging, plastic covers, or by filtering ambient air.
In Vitro Propagation of Hosta decorata ‘Thomas Hogg’ Using Cultured Shoot Tips
Authors: Papachatzi Marietta , Hammer P. Allen , Hasegawa Paul M.
Published: August 2022

Shoot tips proliferated in vitro were used as explants to determine the effects of various nutrient medium components and environmental conditions on shoot multiplication of Hosta decorata L. H. Bailey ‘Thomas Hogg’. The rate of axillary shoot multiplication was stimulated by the addition of either 0.01 or 0.10 mg×liter α-naphthaleneacetic acid (NAA) to medium containing 5 mg×liter 6-benzylamino purine (BA). Indoleacetic acid (IAA) and indolebutyric acid (IBA) did not promote axillary shoot formation. All 3 auxins were effective in promoting adventitious shoot initiation. In medium with 0.1 mg/liter NAA, BA at 5 mg/liter stimulated a higher number of shoots of axillary origin than did N6-isopentenylaminopurine (2iP) or N6-furfurylaminopurine (kinetin). However, equivalent or greater proliferation of adventitious shoots was achieved with 2iP or kinetin. Sucrose was essential for shoot multiplication and 30 g×liter was optimum. Inorganic phosphate (NaH2PO4 · H2O) and adenine sulfate stimulated growth and shoot multiplication while i-inositol, although not essential, enhanced shoot formation at 30 mg×liter. Axillary and adventitious shoot multiplication was optimum under photosynthetkally active radiation (PAR) of 70 or 130µE m-2s-1 at 21°C and under PAR of 70 µE m-2s-1 at 26°C. Rooting of shoots in vitro was obtained on basal medium without growth regulators or on medium containing 0.01 mg/liter NAA, and the plants were successfully established in soil. Plants obtained from culture which had lost leaf margin variegation regained it after receiving a cold room treatment of 3-6°C for 20 weeks.
Studies of Ovipositional Preference of Cabbage Looper on Progenies from a Cross between Cultivated Lettuce and Prickly Lettuce
Authors: Kishaba A. N. , McCreight J. D. , Coudriet D. L. , Whitaker T. W. , Pesho G. R.
Published: August 2022

In the paper, Studies of Ovlpositional Preference of Cabbage Looper on Progenies from a Cross between Cultivated Lettuce and Prickly Lettuce by A. N. Kishaba, J. D. McCreight, D. L. Coudriet, T. W. Whitaker, and G. R. Pesho (J. Amer. Soc. Hort. Sci. 105(6):890–892. 1980), the last sentence of the first paragraph should read: Two of the plant introductions, PI261653 (Lactuca saiigna) and PI274372 (L. serriola) were less preferred as oviposition sites (7). In addition, reference 2 of the literature cited should be deleted and references 3 through 12 should be renumbered 2 to 11 to accurately correspond with citations in the text.
Response of Bell Pepper to Irrigation, Nitrogen, and Plant Population1,2
Authors: Batal K. M. , Smittle D. A.
Published: August 2022

In field experiments, yields of pepper (Capsicum annum L.) were obtained by more frequent irrigation, nitrogen topdressings, and increased plant population. The highest marketable yield resulted when sufficient N was added to maintain soil NO3–N levels between 20 (spring) and 30 (fall) ppm. In both seasons, the number of N topdressings was doubled in order to raise the soil NO3–N maintenance levels from 10 to 20 ppm or from 15 to 30 ppm. Yield increases were influenced by frequent irrigation only when additional N was applied to maintain a higher soil NO3–N. Populations greater than 27,000 plants/ha increased marketable yields in spring and fall by 2.8 and 7.1 MT/ha respectively.
The Effects of Sequential Applications of Different Chemical Growth Regulators on Growth and Flowering of F1 Hybrid Geraniums (Pelargonium × hortorum Bailey)1
Authors: Hamza Ali M. , Koranski David S. , Rogers Marlin N.
Published: August 2022

Sequential treatment of F1 hybrid geranium seedlings with different kinds and concentrations of chemical growth regulators produced well-proportioned plants with increased numbers of large-sized inflorescences and decreased flowering time compared with controls. (2-Chloroethyl)trimethylammonium chloride (chlormequat),α-cyclopropyl-α-(4-methoxzphenyl)-5-pyrimidine methanol (ancymidol) or (2-chloroethyl)phosphonic acid (ethephon) applied 2 to 3 weeks after potting caused increased production of branches and closely spaced initiation of several flower buds. These were hastened in growth and development by subsequent applications of gibberellic acid (GA3). Excessive increases in plant height caused by high-concentration GA3 applications were partly controlled by carefully timed second applications of either ancymidol or chlormequat.
The Relationship between Starch Accumulation and Soluble Solids Content of Tomato Fruits1
Authors: Dinar M. , Stevens M. A.
Published: August 2022

The soluble solids content of ripe fruit of tomato (Lycopersicon esculeutum mill.) is positively associated with starch content early in fruit development. When 14C-sucrose or 14C-glucose were injected, the young fruits of the breeding line LA 1563 contained greater amounts of 14C in starch than those of the cultivars ‘UC 82B’. This, and the larger pool of hexoses in young fruits of ‘UC 82B’, implies that difference in starch synthesis is a primary factor affecting starch levels. The differences between 2 genotypes for fruit respiration and their ability to take up sucrose from an agar medium suggest that starch accumulation is a result of greater sink activity.
Growth Inhibitors in Cucumber Plants and Seeds1
Authors: Lockerman R. H. , Putnam A. R.
Published: August 2022

Testa of cucumber (Cucumis sativus L. PI 169391) seed contain inhibitor(s) that suppressed germination of proso millet (Panicum miliaceum L.) and seedling growth of cucumber. Seed fermentation and/or leaching with distilled water reduced inhibition, while activated charcoal eliminated the toxicity. Inhibitory effects of cucumber seed extracts on cucumber and proso millet germination decreased with maturity of the cucumber seed and fruit. PI 169391 seeds were both autotoxic and allelopathic during early seedling development. Partitioning with organic solvents demonstrated that the toxic compound(s) were polar. Extracts of other seed tissues were non-toxic as were extracts from seed and fruit of ‘Pioneer’ cucumber. Fruit juice extracts from PI 169391 suppressed growth of both cucumber and proso millet.
Influence of Alternating Day and Night Temperatures on Flowering of Freesia hybrida1
Authors: Gilbertson-Ferriss T. , Wilkins H. F. , Hoberg Randy
Published: August 2022

Plants of Freesia hybrida Bailey ‘Moya’, grown from corms and ‘Royal Crown’ from seed flowered when the temperature was 13°C continuously or with 13° during an 8 hour light span or with 13° during a 16 hour dark span both of which were alternated with 24°. Flower quality was poor but marketable on plants treated a 13° light or dark temperature alternated with 24°. Results suggest that the commercial production season could be extended into warm seasons by maintaining 8 hours of inductive temperature (13°) in greenhouses or coolers. Flowering or corm filling did not occur at continuous 24°.
Screening of Carica papaya L. Seedlings for Resistance to Root Rot Caused by Phytophthora palmivora Butl.1
Authors: Mosqueda-Vázquez R. , Aragaki M. , Nakasone H. Y.
Published: August 2022

Papaya seedlings being tested for resistance to Phytophthora palmivora root rot were inoculated with sporangial suspensions which varied from 0 to 18,000/plant. Mortality counts and disease ratings of seedlings taken 1 month after inoculation showed that: (a) developmental resistance increased as seedlings became older and appeared totally developed by the time seedlings were 2 months old; (b) comparisons among papaya lines inoculated with increasing concentrations of inoculum demonstrated a dosage response; (c) 1-month-old papaya lines inoculated with a uniform concentration of inoculum (5,250 sporangia/plant) could be separated into 3 distinct groups. Line 8, ‘Waimanalo’-23, ‘WaimanaIo’-24, and line 40 were resistant; 45-T22 and ‘Kapoho Solo’ were moderately resistant and ‘Higgins’ was susceptible. The correlation between greenhouse and field mortality was r = 0.955, which supports the reliability of the method.
Components of Processed Watermelon Fruit1
Authors: Crandall Philip G. , Kesterson James W.
Published: August 2022

Watermelon fruit [Citrullus lanatus (Thunb.) Matsu. and Nakai] cultivar ‘Charleston Grey’ were processed by removing the rind with a knife, separating the juice from the flesh with a screw-type finisher, and concentrating the juice in a high-temperature, short-time evaporator. The yield was 41% juice, 8% pulp, 1% seeds, and 50% rind on a wet-weight basis. The rind was further processed by chopping, treating with lime, and pressing, and then it was dried; 63% of the wet weight of the rind was water that could be removed by mechanical means. The residue, after juice extraction, was made into an animal feed with a nutrient composition of 13% protein, 7% ether extract, 20% fiber, 5% ash, and 51% nitrogen-free extract. Watermelon rind yielded 20% 150-grade pectin, dry-weight basis.
Abaxial Transpiration and Water Loss in Aseptically Cultured Plum1
Authors: Fuchigami L. H. , Cheng T. Y. , Soeldner A.
Published: August 2022

Scanning electron microscopy was used to investigate leaf epicuticular wax of Prunus instititia L. ‘Pixie’ from aseptically cultured plants before and after acclimatization to the greenhouse. Leaves from plants acclimatized for 2 weeks in the greenhouse had more adaxial wax than those from non-acclimatized (culture flask-grown) plants. Acclimatized plants had more adaxial than abaxial wax. No abaxial wax was observed on leaves of non-acclimatized plants. Stomata were present on the abaxial leaf surface only of both acclimatized and non-acclimatized plants. Epicuticular wax layers surrounded guard cells of acclimatized plant leaves but were not present on non-acclimatized plant leaves. Weight changes in non-acclimatized plant leaves coated with silicon rubber on adaxial, abaxial, and both surfaces indicated that excised leaf water loss occurred only through the abaxial surface. Water loss from plants during the acclimatization process thus may be due to abaxial cuticular and stomatal transpiration.
Influence of Tillage System, Plant Spacing, and Nitrogen on Head Weight, Yield, and Nutrient Concentration of Spring Cabbage1
Authors: Knavel Dean E. , Herron J. W.
Published: August 2022

Spring cabbage plants (Brassica oleracea L. Capitata group) grown by no-tillage culture yielded less than conventionally tilled plants when grown under the same N treatment and spacing. No-till yields could be compensated somewhat by increasing plant population and N, but head size was generally smaller than for conventionally tilled plants. Large head size was positively correlated with high N content of wrapper leaves in 3 of 4 years, while high Ca was associated with large plants or heads in 2 of 4 years.
Inheritance of PGI and LAP Isozymes in Octoploid Cultivated Strawberries1
Authors: Arulsekar S. , Bringhurst R. S. , Voth Victor
Published: August 2022

Genetic analysis of phosphoglucoisomerase and leucine amino peptidase allozymes clearly indicated that the octoploid cultivated strawberries Fragaria × ananassa Duch. are highly diploidized. A 4-locus genetic model is proposed for the PGI allozymes in the octoploid strawberries commensurate with the genomic structure. The LAP system needs further investigation in order to establish the number of loci and alleles present. The possible adaptive value of the biochemical diversity found in the Fragaria species is discussed.
Stem-end Decay and Quality of Low Oxygen Stored ‘d’Anjou’ Pears1
Authors: Chen P. M. , Spotts R. A. , Mellenthin W. M.
Published: August 2022

Stem-end decay caused by several several fungi was less in ‘d’Anjou’ pears (Pyrus communis L.) stored in a low O2 (1% O2 + 0.05% CO2, −1.1°C) room than in ones stored in −1.1° air. Ethylene concentration in the low O2 room was about 120 times higher than in the air room hut did not cause fruit softening or peel degreening after 8 months storage at −1. 1°. The 1% O2-stored fruit softened faster than the air-stored fruit during ripening and also ripened with better dessert quality. Juice binding capacity of ripened fruit pulp from 1 % O2-stored pears was greater than that of air-stored fruit; the texture of ripe fruit from the 1% O2 storage was buttery and juicy while that of air-stored fruit was coarse and dry. The high performance liquid chromatographic analysis revealed that organic acids in 1% O2-stored and air-stored fruits were qualitatively identical.
Effects of Between-row Spacing, Cultivation, and Genotype on Growth and Yield of Black Beans1
Authors: Kahn Brian A. , Stoffella Peter J. , Sandsted Roger F. , Hymes W. Larry
Published: August 2022

Two lines of black bean (Phaseolus vulgaris L.), ‘70001’ and ‘Strain 39’, were grown at between-row spacings of 76, 61, and 46 cm. Cultivation treatments included an uncultivated check and a single cultivation at 1 of 3 plant growth stages: first trifoliolate leaf fully expanded; anthesis; or pod elongation. Root weight, shoot weight, and shoot:root ratio of individual plants decreased linearly as between-row spacing decreased. Biological yield increased linearly as between-row spacing decreased, but seed yield and harvest index did not show significant responses to spacing. None of the measured parameters gave a significant response when the uncultivated control was compared with the average of the 3 time-of-cultivation treatments. Root weight of individual plants and biological yield gave quadratic responses within the 3 time-of-cultivation treatments, both decreasing most markedly with cultivation at the pod elongation stage. Plants of ‘70001’ were larger and lodged less compared to those of ‘Strain 39’. Seed yields of both lines were similar. Results suggest that a single shallow cultivation may be used for black beans grown in narrow rows through anthesis. Although cultivation at the pod elongation stage was generally not detrimental to seed yield, it is not recommended.
Isolation and Characterization of Glutamate Synthase in the Apple1
Authors: Kang Seong-Mo , Titus John S.
Published: August 2022

Glutamate synthase (L-glutamine:2-oxoglutarate aminotransferase, NADPH-oxidizing, E.C. 2.6.1.53) was isolated from bark tissue of the apple (Malus domestica Borkh. cv. Golden Delicious). The enzyme was partially purified by ammonium sulfate fractionation and diethylaminoethyl-cellulose chromatography. The enzyme was specific for L-glutamine and α-ketoglutarate as a nitrogen donor and acceptor, respectively. Both NADH and NADPH were found to be equally effective as reductants, although NADH appeared to be a physiological electron donor. The enzyme exhibited maximal activity at pH 8.0. Michaelis-Menten constants of the enzyme were 440, 50, 2.6, and 2.4 μΜ for L-glutamine, α-ketoglutarate, NADH and NADPH, respectively. L-Glutamate inhibited the enzyme activity competitively with respect to α-ketoglutarate, the estimated inhibition constant being 0.48 mm. The significance of this enzyme in the annual nitrogen recycling process in the apple is discussed.
Rickettsia-like Bacteria in Peach Roots Preceded Development of Visual Symptoms of Phony Peach Disease and Changes in Leaf Elemental Concentrations1,2
Authors: Evert Dean R. , Gaines T. Powell , French William J.
Published: August 2022

Rickettsia-like bacteria (RLB) are the presumptive cause of phony peach disease and are most numerous in peach (Prunus persica (L.) Batsch) roots. Of apparently healthy peach trees in a heavily infected orchard, 54% had RLB in root samples evaluated by 400 × phase contrast microscopy. Removing all peach trees with visible symptoms of phony peach disease would minimize the number of trees in the orchard infected with RLB. Of trees visibly infected with phony peach disease, 8% had root samples free of RLB on both sampling dates. Leaf concentrations of Mg and B varied significantly (P < 0.7%) with RLB levels in peach roots on 3 of 4 sampling dates. No element tested (P = 5%) separated roots free of RLB on two sampling dates from roots averaging 1 to 9 RLB per microscope field on one date and free of RLB on another date. RLB in peach roots preceded development of visible symptoms of phony peach and changes in leaf elemental concentrations. Soil analysis did not identify RLB infected tree roots (P = 5%).
Influence of Soil pH, Sulfur, and Sawdust on Rabbiteye Blueberry Survival, Growth, and Yield1
Authors: Cummings G. A. , Mainland C. M. , Lilly J. P.
Published: August 2022

Growth and yield of rabbiteye blueberries (Vaccinium ashei Reade cv. Tifblue) decreased as soil pH was raised from 4.5 and 7.0. Plant survival decreased at pH 6.0 and 6.5 and all bushes died at pH 7. After 3 growing seasons, bushes were sacrified, plots split, and S added to lower pH to 5.00 or weathered sawdust was added to all plots and the experiment replanted. Replanted bushes in the sawdust plots were greener and produced greater linear growth during the first growing season. Sawdust, even the first year, overcame the harmful effects of high initial soil pH except at pH 7. Optimum growth and production resulted from incorporated sawdust at initial soil pH 5.0. Addition of S was less effective than sawdust in overcoming the harmful effects of high soil pH.
The Effect of Soil Phosphorus Levels on Mycorrhizal Infection of Field-grown Onion Plants and on Mycorrhizal Reproduction1
Authors: Nelsen C. E. , Bolgiano N. C. , Furutani S. C. , Safir G. R. , Zandstra B. H.
Published: August 2022

Seeds of onion (Allium cepa, L.) were sown on 2 muck soils that were high and low in available phosphorus and which contained an indigenous population of mycorrhizal spores (Glomus sp.). Treatments were 4 levels of P (0, 30, 97, and 193 kg/ha) and inoculum of the mycorrhizal fungus Glomus etunicatus Becker & Gerdemann. In the soil that was low in available P (3 kg/ha) bulb weight increased with added P. Root infection by the mycorrhizal fungus and mycorrhizal spore numbers in the soil were negatively correlated with added P. Bulb weight and mycorrhizal spore number at harvest increased when mycorrhizal inoculum was added to the soil. In the soil that was high in available P (97 kg/ha) bulb weight, root infection, and spore numbers were not influenced by added P or added mycorrhizal inoculum. Root infection data from both soils suggested a threshold level of soil P below which mycorrhizal infection was high and above which infection was low. The levels of P commonly added to muck soils may negate any usefulness of mycorrhizae but addition of P might be reduced if mycorrhizal spore numbers were increased through inputs of mycorrhizal inoculum or cultural practices.
Performance of Six Apple Cultivars on M9, M26, and M7 Rootstocks1
Authors: Denby L. G.
Published: August 2022

‘Harrold Red Delicious’, ‘Golden Delicious’, ‘Spartan’, ‘McIntosh’, ‘Tydeman's Red’ and ‘Quinte’ apples were compared over a 12-year period on Mailing (M) 9, M 26 and M 7 rootstocks on variable soil at Summerland. ‘Harrold Red Delicious’ performed well on M 7, poorly on M 26 and M 9. ‘Golden Delicious’ was precocious and productive on all rootstocks, with fairly uniform performance on M 7 and M 26, but was extremely variable on M 9. ‘Spartan’ trees were precocious, productive and uniform on M 7, but variable on M 26 and of poor habit on M 9. ‘McIntosh’ performed best on M 7, being variable on M 26 and M 9. ‘Tydeman's Red’ and ‘Quinte’ lacked precocity and productivity on all 3 rootstocks.
Tree Yield and Nut Characteristics of Pecan with Drip Irrigation under Humid Conditions1
Authors: Worley Ray E.
Published: August 2022

Drip irrigation on 1 and 2 sides of pecan [Carya illinoensis (Wang.) Koch.] trees was programmed to irrigate when soil water suction 61 cm from the emitter was greater than 0.1 bar at either 15, 30, or 45 cm depth. Results were compared with no irrigation. The data indicate little advantage of 2 lines of emitters over one line when the same number of emitters/tree are used. The data often favored 1 line over 2 lines. Total yield of pecans was increased substantially by drip irrigation on one side (‘Desirable’ and ‘Elliott’) or both sides of the tree (‘Elliott’), but increases from ‘Farley’ were not significant. In 1968, an extremely dry year, ⅓–½ of the shucks did not dehisce completely on nonirrigated trees while 1 to 7% of the shucks did not dehisce on irrigated trees. Irrigation increased nut size. Percentage kernel was increased by irrigation in 1968 but not in other years. In 1968, percentage fancy kernels was almost doubled by irrigation for ‘Desirable’ but was reduced for ‘Elliott’.
Growth and Flowering of Vigorous Apple Trees as Affected by Summer or Dormant Pruning1
Authors: Marini Richard P. , Barden John A.
Published: August 2022

Summer pruning of ‘Starking Delicious’, ‘Golden Delicious’, or ‘Stayman’ apple (Malus domestica Borkh.) trees in mid-August (about 14 weeks after full bloom) did not suppress shoot growth the following year, as compared to similar pruning prior to budbreak in early April. ‘Stayman’ trees pruned in June had more regrowth than those pruned in August. A 1% naphthaleneacetic acid (NAA) solution applied to the summer pruning cut prevented regrowth. The increase in trunk and branch circumference was reduced by August pruning, as compared to dormant pruning. Summer pruning did not influence total bloom the year following treatment, but summer pruning for 2 consecutive years reduced the amount of bloom on 2-yr-wood. Cutting to the first spur on 2-year-wood in August did not suppress shoot growth the following year as compared to heading back to 4 leaves on current season's wood.
Salt Tolerance of Eight Ornamental Tree Species1
Authors: Francois L. E.
Published: August 2022

Salt tolerance of 8 ornamental tree species was determined in plots artificially salinized with NaCl and CaCl2. Tolerant species such as Italian stone pine (Pinus pinea L.) and evergreen pear (Pyrus kawakamii Hayata) were affected very little bv soil salinities of 9 dS/m (electrical conductivity of the saturation extract: ECe). Sweet gum (Liquidambar styraciflua L.), cherry plum (Prunus cerasifera J. F. Ehrh), Southern magnolia (Magnolia grandiflora L.), orchid tree (Bauhinia purpurea L.h crape myrtle (Lagerstroemia indica L.), and tulip tree (Liriodendron tulipifera L.) exhibited moderate to severe injury symptoms and a 33% or greater growth reduction. Injury symptoms became more severe with each growing season.
Screening Azalea Cultivars for Sensitivity to Nitrogen Dioxide, Sulfur Dioxide, and Ozone Alone and in Mixtures1
Authors: Sanders J. S. , Reinert R. A.
Published: August 2022

Eight cultivars of azalea were tested for sensitivity to 0.25 ppm of nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3), alone and in mixture. Sixty-eight days after pruning, the 1 yr-old liner plants were exposed to the pollutants for 6, 3-hr fumigations over a 4 week period. Cultivars demonstrated a range of sensitivity (tolerant to moderately sensitive) based on both visible injury and growth. Neither NO2 nor SO2 (alone and in combination) induced foliar injury on any of the cultivars. Ozone and mixtures of O3 with NO2 and/or SO2 induced small amounts of injury (10% or less) to foliage of ‘Pink Gumpo’, ‘Mme. Pericat’ and ‘Red Wing’. ‘Red Luann’, ‘Glacier’, and ‘Hershey Red’, sustained >10% foliar injury from mixture treatments containing O3. No significant interactions among NO2, SO2, and O3 were detected by measurements of plant weight. The pollutants did not change the weight of leaves or stems of ‘Pink Gumpo’ and ‘Mme. Pericat’. Significant weight loss occurred in leaves or stems from exposure of ‘Hershey Red’, ‘Red Luann’, and ‘Red Wing’ to treatments containing O3 and from exposure of ’Mrs. G. G. Gerbing’, ‘Glacier’, and ‘Red Luann’ to treatments containing SO2.
Origin and Distribution of Secondary Articulated Anastomosing Laticifers in Manilkara zapota van Royen (Sapotaceae)1
Authors: Mustard Margaret J.
Published: August 2022

Differentiating articulated secondary vertical laticifers and secondary ray laticifers occur in the phloem in the terminal 1.3 cm of sapodilla branches. In older branches and in the bark of mature trees, the outer ends of laticifer rays become dilated and ultimately lose their identity within the secondary laticiferous mass which lies internal to the surface layers of cork. The outer laticiferous mass may be largely composed of secondary ray laticifers. Dilation of secondary laticifer rays displaces other components of the secondary phloem including some of the secondary vertical laticifers. This investigation clearly shows that anastomoses occur between the components of the secondary articulated laticifer system of the sapodilla.
Water Stress Effects on Pickling Cucumber1
Authors: Ortega D. G. , Kretchman D. W.
Published: August 2022

The rate of increase in vine length and node number of fruiting plants of cucumber (Cucumis sativus L.) was reduced after 1 week of water stress and completely inhibited after 2 weeks. Control plants also experienced a reduction in growth rate of vine length and node number but not as pronounced as in the stressed plants. Fruit growth rate was severely reduced in water stressed plants, however, the larger fruits were less affected than the smaller ones. Osmotic and water potentials were lower in the large stressed fruits than in the small stressed fruits.
Quantum Flux Density Studies of Chrysanthemum in a Controlled Environment with High-pressure Sodium Lamps. I. Rooting Studies1
Authors: Stefanis James P. , Langhans R. W.
Published: August 2022

Growth of chrysanthemum (Chrysanthemum morifolium Ramat) was studied as a function of quantum flux density (QFD), QFD duration, and temperature. Unrooted cuttings were rooted under high-pressure sodium (HPS) lamps in a controlled environment (CE) at 4 QFD, 3 QFD durations, and 3 temperatures, and plants were grown to flowering in a greenhouse to determine treatment effect on flowering time and plant size at flowering. Increasing QFD duration was more effective in increasing root and shoot dry weight than increasing QFD. Root and shoot dry weights were greatest at 21°C after 13 days rooting. Light treatment during rooting had no effect on flowering time or shoot length at flowering, but there were differences of up to 35% in fresh weight at flowering. A photochlorosis was observed on all treatments irradiated with HPS lamps; the photochlorosis was irreparable at a QFD of 420 μEm−2s−1.
Vermiculite, a Source of Metals for Arabidopsis thaliana1
Authors: Tingey David T. , Raba Susan , Rodecap Kent D. , Wagner Jerome J.
Published: August 2022

Plants of Arabidopsis thaliana (L.) Heynh. were grown in hydroponic systems using vermiculite as a growth medium at nutrition levels ranging from adequate to deficient. Plants grown on the low-total nutrient or low-iron nutrient contained more of iron, magnesium, and aluminum, frequently twice as much as plants grown at normal nutrient levels. Plants grown in iron-deficient nutrient were initially chlorotic; after about 5 weeks the chlorosis disappeared and these plants contained higher tissue iron levels than those receiving iron in the solutions. Concentrations of aluminum in the foliage ranged between 2 and 5 mg/g dry weight. Chemical analysis of the nutrient solution indicated that there was not sufficient aluminum, as a contaminant, in the nutrient solution to account for the concentrations that occurred in the plant tissue. Apparently, plants experiencing nutrient stress may modify the root environment so that vermiculite is solubilized and iron, magnesium, and aluminum are taken up by the plant. Levels of aluminum that accumulate in Arabidopsis foliage suggest that it should be classified as an aluminum-accumulating plant.
Physical Properties of Media Composed of Peanut Hulls, Pine Bark, and Peatmoss and their Effects on Azalea Growth1
Authors: Bilderback T. E. , Fonteno W. C. , Johnson D. R.
Published: August 2022

Equal volumes of peanut hulls, pine bark, and sphagnum peatmoss were combined into 5 media. Particle size distribution, total porosity, air space, easily available water, water buffering capacity, and bulk density were determined for each medium. Top dry weight, root dry weight, and percent growth of Rhododendron indicum (L.) Sweet cv. George L. Taber were measured 14 weeks after potting in 1-liter containers. Peanut hulls increased particle size, total porosity, and air space, and decreased easily available water, water buffering capacity, and bulk density of media. Peatmoss generally reduced total porosity and air space and increased easily available water, water buffering capacity, and bulk density regardless of other component combinations. Top dry weight, root dry weight, and percent growth were greater in peanut hull-containing media. Addition of peatmoss to the container media tended to produce less growth.