bluuebunny/crossref_metadata_2025 huggingface dataset:
Photosynthesis in the Rose; Effect of Light Intensity, Water Potential and Leaf Age1
Authors: Aikin Warren J. , Hanan Joe J.
Published: August 2022

The net rate of 14CO2 uptake was determined on individual leaves of Rosa hybrida, cv. ‘Forever Yours’, budded on Rosa manetti and grown in gravel. Rose leaves were found to reach an average peak of 11 mg CO2 dm−2 hr−1 about 6 days after the red color disappeared on the leaf underside, or 32 days after harvesting the previous flower on the parent cane. Thereafter, CO2 uptake declined during 14 days to 5 to 6 mg CO2 dm−2 hr−1. At ambient CO2 concentrations of 500 ppm, the maximum net uptake was near 3400 ft-c. However, internal plant water potential influenced the CO2 uptake by reducing it at each increase of radiant energy. This resulted in light saturation at lower energies the lower the plant water potential. Radiant energy affected both net CO2 uptake and water potential. Wilting was generally observed to occur at about –13 bars, and maximum rates of CO2 uptake were found at potentials of –8 bars or higher, over a range of 350 to 450 microeinsteins, or 3000 to 3500 ft-c.
Antitranspirant Effects on the Water Status of ‘Manzanillo’ Olive Trees1
Authors: Davenport D. C. , Uriu K. , Hagan R. M.
Published: August 2022

The water balance of both irrigated and unirrigated olive (Olea europaea L. cv. Manzanillo) trees was improved by spraying a film-forming antitranspirant (AT). This was evidenced by increased resistance to water vapor diffusion from the leaves, reduced daytime shrinkage of limbs, and increased leaf and fruit water potential. The improvement in plant water potential by AT was equivalent to the effect of an irrigation. Transpiration at night through incompletely closed stomates, especially when night humidity was low, retarded normal nocturnal rehydration of the olive limbs and fruit. The improved water balance of AT-treated olive trees indicated a potential for increasing fruit growth.
Embryo Immaturity and Dormancy of Black Ash1
Authors: Vanstone D. E. , LaCroix L. J.
Published: August 2022

The seed of black ash, Fraxinus nigra Marsh., borne in a single samara, normally ripens in the autumn. At that time the seed contains an embryo which is both immature and dormant. In order to overcome this dual delay to germination, the seed can be matured in moist peat moss for 18 weeks at 21° followed by after-ripening for 18 weeks at 4°.

Treatment at warm temperature matured the embryo, whereas the subsequent cool temperature after-ripened the dormant embryo. During maturation the embryo length doubled, the dry weight tripled and the cotyledons showed visual evidence of differentiation. On the other hand, for dormancy to be overcome a metabolic shift in the embryo occurred during the cool period to provide the active metabolism needed by a germinating seed. This was reflected by a 5 percent per week increase in the respiration capacity of the embryo and a reduction in the amount of oil in the seed.
Pine Vole Control with Anticoagulant Baits1
Authors: Byers Ross E. , Young R. S.
Published: August 2022

Hand placement of 2-Diphenylacetyl-1,3-indandone (Diphacinone, DPN) and [(chloro-4-phenyl)-1-phenyl-1] acetyl-2-dioxo-1-3-indane (Chlorophacinone, CPN) baits applied in 2 applications at ca 30 day intervals at 11.2 kg/ha (10 lbs/A) each were effective in the control of pine voles (Microtus pinetorum LeConte) in apple orchards. In a cultural experiment designed to control pine voles, one Diphacinone preparation gave near 100% control with one application in plots previously cultivated and treated with residual herbicide in July and November.
Postharvest Quality of Machine-harvested Strawberries 1
Authors: Morris J. R. , Cawthon D. L.
Published: August 2022

Firm-fruited strawberries (Fragaria × ananassa Duch.) for processing can be mechanically harvested, properly handled and then held for up to 48 hours at 24°C for 7 days at 1.7° without excessive quality loss. High mold count and a reduction in other quality attributes occur after 96 hours at 24°. Ripe fruit held for 48 hours at 24° and then processed was acceptable to a sensory panel. The effects of overwrapping appeared to be limited to quality changes associated with dessication. Benomyl treatment had a suppressing effect on mold count and reduced loss of soluble solids.
Frost Hardiness of Ericoideae1
Authors: Sakai A. , Miwa S.
Published: August 2022

Dormant twigs of a number of Ericoideae (genera Erica and Calluna) species were collected in midwinter at Gotemba, Shizuoka Prefecture. These twigs were artificially hardened at the temperature from −1 to −3°C for 15 days to increase hardiness and then subjected to controlled test temperatures to assess their hardiness. European ericas were observed to be much hardier than those from South Africa, resisting freezing from −15 to −20°C. South African ericas were hardy only from −5 to −8°C. Calluna cultivars survived freezing down to −30°C.
The Influence of Rootstock and Strain on Growth and Production of ‘Delicious’ and ‘Golden Delicious’ Apple Trees1
Authors: Seeley E. J. , Stahly E. A. , Kammereck R.
Published: August 2022

The influence of 6 rootstocks on growth and productivity of spur and non-spur ‘Delicious’ and ‘Golden Delicious’ apple (Malus domestica Borkh.) trees was investigated. The spur-type ‘Delicious strain (‘Miller Spur’) consistently produced more fruit per tree than the regular-type strain (‘Red Prince’). In contrast, standard ‘Golden Delicious’ produced as much or more per tree than the spur-type strain ‘Goldspur’ even in the early years. ‘Miller Spur Delicious’ trees were largest on seedling rootstock, intermediate on Mailing (M) 104, and smallest on M 111, M 106 and M 7. ‘Goldspur Golden Delicious’ resembled ‘Miller Spur Delicious’ in size, except that trees were significantly smaller on M 7 than on M 111 and M 106. At the end of the 9th season, ‘Red Prince Delicious’ and ‘Golden Delicious’ were largest on seedling, followed by M 111, M 106, M 7 and M 26 in descending order. Biennial bearing of some trees on all rootstocks reduced yield and increased tree-to-tree yield variance.
Vegetative Propagation in Everbearing Strawberry as Influenced by a Morphactin, GA3, and BA 1
Authors: Biaiñ de Elizalde María M. , Guitman María R.
Published: August 2022

Applications of the morphactin IT 3456 (methyl-2-chloro-9-hydroxy-fluorene-9-carboxylate) (Fragaria × ananassa Duch., cv. Rabunda) at concentrations of 10 to 200 ppm promoted crown division; IT 3456 at 15 ppm with benzyladenine (BA) stimulated vegetative propagation, evaluated by adding the total number of runner plants to that of side-crowns. Gibberellic acid (GA3) alone or morphactin with GA3 had no significant effect on runnering or lateral branching.
Fall Defoliation Date and Seasonal Carbohydrate Concentration of Pecan Wood Tissue 1
Authors: Worley Ray E.
Published: August 2022

Fall defoliation was followed by a depletion of carbohydrate (CHO) reserves and reduction or prevention of yield if defoliation occurred prior to November 1. Refoliation of August-defoliated trees restored the depleted reserves in current season’s wood tissues by December 1 but either completely prevented or greatly reduced yield the next year. September defoliation caused the greatest depletion of reserves and prevented pistillate or staminate flower production the next year. Defoliation on November 1 had no significant effect on CHO reserves.
Effect of Preharvest Antitranspirant Sprays on the Size and Quality of ‘Delicious’ Apples at Harvest 1
Authors: Miller Stephen S.
Published: August 2022

Sprays of poly-l-p-methen-8-9-diyl (Vapor Gard) or di-l-p-menthene (Wilt Prüf NCF), two antitran-spirants, or emulsifiable A-C polyethylene and octyl phenoxy polyethoxy ethanol (Plyac), a latex type spray adjuvant, at 0.5, 1.0 and 2.0% applied 14 days before “normal” harvest generally increased the size of ‘Stark-rimson Delicious’ apples (Malus domestica Borkh.) over unsprayed controls under conditions of low soil moisture. Antitranspirant or spray adjuvant treatments had little or no effect on average fruit diam when applied to trees growing under adequate soil moisture. The rate of chemical application had an effect on the fruit size response. Results indicated no additional benefit in fruit size when fruit were harvested 21 days after treatment (7 days after normal harvest). Treatments generally reduced fruit firmness and hastened the loss of starch from the fruit flesh.
Variation in Ozone Sensitivity and Symptom Expression among Cultivars of Phaseolus vulgaris L. 1
Authors: Butler L. Knudson , Tibbitts T. W.
Published: August 2022

Eighteen bean cultivars were grown from seed in a growth chamber and exposed to 140 pphm ozone for 1 hr. ‘Sanilac,’ ‘Tenderette,’ ‘Blue Lake Stringless,’ ‘Bush Blue Lake 290,’ and ‘Spurt’ were the most sensitive to ozone; ‘Pinto 111’ was moderately sensitive; and ‘Black Turtle Soup’ and ‘French’s Horticultural’ were the most resistant. Necrotic flecking, dispersed over most of the leaf, characteristically developed on the cultivars ‘Spurt,’ ‘Early Gallatin,’ ‘Orbit,’ and ‘French’s Horticultural.’Necrotic patching, restricted to certain areas of the leaf, characteristically developed on ‘Sanilac,’ ‘Blue Lake Stringless,’ ‘Bush Blue Lake 290,’ ‘Bush Blue Lake 274,’ ‘Apollo,’ ‘Coloma,’ ‘Tempo,’ and ‘Black Turtle Soup.’ Pigmented lesions on adaxial surfaces developed on all ‘Sanilac’ plants and on some ‘Resistant Asgrow Valentine’ and ‘Pinto 111’ plants. A generalized chlorosis was observed on some plants of all cultivars. Cultivar sensitivity was evaluated by determination of chlorophyll concentration and visual observations. For most cultivars, similar estimates of injury were obtained by the 2 methods. Injury assessments differed the most for cultivars that developed the necrotic patching symptom.
Blossom-end Rot of Tomato Fruit as Influenced by Osmotic Potential and Phosphorous Concentrations of Nutrient Solution Media1
Authors: Cerda Antonio , Bingham F. T. , Labanauskas C. K.
Published: August 2022

Tomato plants (Lycopersicon esculentum Mill.) were grown to maturity in complete nutrient solution with osmotic potentials (sψo) of −0.8, −2.4, −4.4 and −6.4 bars from NaCl additions, and 0.5, 5.0, and 50 ppm P as variables. The objectives were to evaluate the effects of sψo and P and their interactions with respect to fruit yield and quality, and nutrient concentrations in the plants and fruits. Reducing the sψo (increasing negative values) by NaCl addition significantly decreased tomato fruit yield, but increased the percentages of soluble solids, total solids, blossom-end rot (BER) incidence and non-marketable fruit. Increased solution salinity resulted in higher leaf concentrations of P, Na and Cl. Increased nutrient solution P levels (Ps) significantly increased fruit yield, but decreased the percentage of fruit soluble solids and BER incidence. Leaf P, Ca and Cl concentrations of plants grown in the high P nutrient solution were higher than those of the leaves from low P solution plants. The incidence of BER was greatest under low sψo and low Ps. Reduced Ca concentrations of leaves and mature fruit were associated with the BER development. The Ca concentration of mature normal fruit varied from 0.039 to 0.076% compared with 0.028 to 0.043% for mature BER fruit. Leaf Ca concentrations of 1.5 to 2.0% were associated with the BER condition.
The Effect of Post-veneralization Temperature on Seedstalk Elongation and Flowering in Carrots1
Authors: Hiller L. K. , Kelly W. C.
Published: August 2022

Seedstalk height of carrot (Daucus carota L.) was reduced as the post-vernalization temperature increased from 15/21° to 27/32°C (night/day) with no significant effect on flowering and seed formation. Seedstalks of ‘Royal Chantenay ’ carrot were most affected by the high temperatures and ‘Scarlet Nantes’ were the least affected while ‘Danvers 126’ was intermediate. Few plants had macroscopic seedstalk development 6 weeks after vernalization although the temperature during this period had a permanent influence on ultimate seedstalk height. Carrots grown at 27/32° during the initial 6 weeks following vernalization and then transferred to the optimum 15/21° grew no taller than plants held at 27/32°. Vernalization temperatures of 0°, 5°, and 10° for 10 weeks did not affect the percentage of plants flowered, time of bolting, or rate of seedstalk elongation. Ultimate seedstalk height was reduced only in ‘Royal Chantenay’ vernalized at 10°. Flowering was decreased by post-vernalization temperatures of 27/32° and 2l/27°C when carrots were stored only 5 weeks at 5° but not, after storage for 10 weeks or more. Increasing the vernalization time to 10 weeks hastened the rate of bolting in all three cultivars and increased ultimate seedstalk height in only ‘Royal Chantenay’ and ‘Danvers 126.’ Temperature during the first year of root growth, foliage removal from mature roots prior to storage, and photoperiod following vernalization did not affect seedstalk elongation or flowering.
The Influence of Node Number, Light Source, and Time of Irradiation during Darkness on Lateral Branching and Cutting Production in ‘Bright Golden Anne’ Chrysanthemum1
Authors: Heins R. D. , Wilkins H. F.
Published: August 2022

Plants of Chrysanthemum morifolium Ramat. cv. Bright Golden Anne irradiated as a day continuation or night interruption with light from cool white fluorescent tubes wrapped with red cellophane (red) produced more cuttings than plants irradiated with incandescent light. There were no significant differences in cutting production when plants were irradiated just prior to dawn. Increased cutting production from plants irradiated with red light was attributed to increased axillary bud activity, especially at the middle nodal position. When shoots were pruned to 4 or 8 nodes, the apical axillary bud produced the maximum number of cuttings and the basal produced the minimum, irrespective of light quality or time span of irradiation.
Effect of Ethylene, Maturity, and Attachment to the Parent Plant on Production of Volatile Compounds by Muskmelons1
Authors: Bliss Meredith L. , Pratt Harlan K.
Published: August 2022

Gas samples from the central cavities of 3 cultivars of muskmelon fruits (Cucumis melo L.) were resolved by gas chromatography into at least 12 organic volatile fractions. Harvesting of ‘Top-Mark5 and ‘PMR-455 cantaloupe up to 12 days before normal abscission did not reduce the final concentration of volatiles attained. Production of volatiles by cantaloupe was inhibited while still attached to the parent plants, but no evidence for inhibition by the parent plant was obtained in ‘Honey Dew’, nor was the final concentration of volatiles reduced by early harvest. High concentrations of exogenous ethylene applied to harvested melons accelerated the onset of production of the organic volatiles but did not significantly affect their ultimate concentrations. Exogenous ethylene altered the relative amounts of at least 2 fractions. The production of volatiles is closely coordinated with the other aspects of ripening, but the control mechanisms appear to be different.
Effect of Physiological Age of Fruit, Temperature, Relative Humidity, and Formulations on Absorption of l4C-release by ‘Valencia’ Oranges1
Authors: Kossuth S. V. , Biggs R. H. , Martin F. G.
Published: August 2022

Absorption of 5-chloro-3-methyl-4-nitro-lH-pyrazole (Release) by ‘Valencia’ fruit (Citrus sinensis (L.) Osb) was determined at 6 different times of the year under 8 temperature and humidity regimes. Significantly greater absorption occurred with immature than with mature fruit. In general, adjuvants did not increase uptake over an aqueous control. The 3-way combination of Release plus Sweep plus 1 ppm cycloheximide (CYH) in April and May significantly increased uptake as did Release plus a formation of chlorothalonil (Sweep) on regreened fruit in July. One ppm CYH caused sufficient tissue damage to stimulate active uptake whereas 20ppm is toxic and inhibits uptake and/or symplastic retention. Best absorption for April and May, the usual harvest period, was obtained at 33°C and 50 to 65% relative humidity. Mature, regreened oranges in July had higher 14C-Release absorption than fruit from the same trees tested in April.
Controlling Tomato Transplant Height with Chlormequat, Daminozide, and Ethephon1
Authors: Pisarczyk James M. , Splittstoesser Walter E.
Published: August 2022

(2-Chloroethyl)phosphonic acid (ethephon), succinic acid-2,2-dimethylhydrazide (daminozide) or (2-chloroethyl)trimethylammonium chloride (chromequat) inhibited transplant growth of tomato (Lycopersicon esculentum Mill.) when applied in the glasshouse. In descending order of effectiveness were daminozide-chlormequat combinations, daminozide, ethephon, and chlormequat. Ethephon, daminozide, or chlormequat reduced transpiration. Clipped plants were delayed in fruit set 1 month while daminozide-chlormequat and chlormequattreated plants were delayed 10 days. Total season yield was unaffected by any treatment.
Effect of Seeding Rate, Pattern, Row Position, and Clipping on Size Uniformity of Field-grown Tomato Transplants1
Authors: Williamson R. E. , Jaworski C. A.
Published: August 2022

Coated seed of tomato (Lycopersicon esculentum Mill.) were precision seeded at 4 rates and 3 patterns to determine the effects on size variation of field-grown transplants. No significant differences in the number of marketable or cull transplants were obtained with the 3 planting patterns. Seeding rates greater than 63 seeds/m usually increased the number of cull transplants with no significant increase in the number of marketable transplants. About 20% more marketable transplants were produced in the 2 inside rows than in the 2 outside rows on 4 row beds.
Seed Coat Scarification of Albizia julibrissin Durazz. by Natural Mechanisms1
Authors: Gogue G. J. , Emino E. R.
Published: August 2022

Fungal and fire treatments were applied to seeds of Albizia julibrissin to simulate natural mechanisms of seed coat scarification. Seeds in unsterilized soil which contained natural microorganisms resulted in increased germination compared to seeds in sterilized media. Germination in cultures of Rhizoctonia, Fusarium, and Pythium indicated Rhizoctonia was most effective as a seed scarifier. Fire treatment at 1, 3, 5, and 10 seconds indicate that 1 second enhanced seed germination. Scanning electron micrographs of treated seed indicated that fungal hyphae alters the surface of the macrosclereid cells which may allow for imbibition of water. Seeds sub-jected to fire had large cracks in the macrosclereid layer.
Differential Thermal Analysis and Freezing Injury in Cold Hardy Blueberry Flower Buds1
Authors: Biermann J. , Stushnoff C. , Burke M. J.
Published: August 2022

Freezing injury of highbush blueberry flower buds (Vaccinium corymbosum L. cv. Rancocas and an experimental hybrid) were investigated after natural freezing and by differential thermal analysis (DTA). Terminal buds were less hardy than median and basal buds on the same twig. Apical, less mature florets were also less hardy than median or basal, more mature florets within each bud. DTA analysis of intact flower buds showed that a rate independent free water exotherm was followed by numerous rate dependent floret exotherms. Floret lethality was associated only with the rate dependent low temperature exotherms. Buds were held over water-glycerol solutions in desiccators so that they came into equilibrium with a relative humidity of 100%, 98% or 96% at 4°C. Artificially hydrated buds were hardy to –10° and artificially dehydrated buds were 15°C hardier. A mean survival temperature of the florets (MSTF) from DTA analysis, derived at slow cooling rates related closely to lowest survival temperature (LST66) from artificial freezing hardiness tests. In mid-winter, under environmental conditions of low temperature and low relative humidity, flower buds of a hardy hybrid lost all DTA exotherms and were hardy to at least –40°. Tissue dehydration and accompanying loss of floret low-temperature exotherms was associated with extreme cold tolerance of blueberry flower buds with the hardy experimental hybrid.
Changes in Pectic Substances in Ripening Pears1
Authors: Ben-Arie Ruth , Sonego Lillian , Frenkel Chaim
Published: August 2022

The compositional changes occurring in the cell wall of maturing and ripening pear fruits (Pyrus communis L. cv. Spadona) were examined in relation to the activity of pectolytic enzymes and cellulase. Fruit softening was accompanied by a rise in water and EDTA-soluble pectic fractions, and in free galacturonic acid. The latter reached peak levels after 15 weeks of cold storage and thereafter declined. Simultaneously with the degradation of pectin there was a 4 to 5 fold increase in polygalacturonase activity, but pectin-methyl-esterase activity declined as it did throughout the harvest and storage seasons. Cellulase activity which was present also in immature fruit increased 2 to 3 fold as the fruit softened, but in the last stages of softening it decreased. Treatment of the firm fruit with partially purified preparations of cellulase and polygalacturonase both caused a dissolution of insoluble pectin material.
Influence of Cucumber Mosaic Virus on Growth and Elemental Composition of Susceptible (Capsicum Annuum L.) and Resistant (Capsicum Frutescens L.) Peppers1
Authors: Cordrey T. D. , Bergman E. L.
Published: August 2022

A greenhouse and a growth chamber experiment were conducted to study the influence of cucumber mosaic virus (CMV) on growth and elemental composition of a hydroponically-grown, susceptible and a resistant pepper cultivar. Foliar symptoms were more severe and appeared 2 weeks earlier on the CMV-infected susceptible than on the CMV-infected resistant cultivar. CMV-infected susceptible plants were stunted before foliar symptoms appeared. Roots were stunted to a greater extent than the aerial portions. Virus infection had no effect on the growth of the resistant cultivar. The amount of solution taken up by the infected susceptible plants was lower than by noninfected ones either before or after symptoms appeared on terminal leaves. The pH of the nutrient solution in which the infected plants were grown was lower prior to symptom expression and conductivity readings were higher than for the solution with noninfected plants. At 1 week after inoculation, prior to the expression of foliar symptoms, concentrations of P, K, Mn, Fe, and Cu were lower in the CMV-infected susceptible than noninfected plants. At 3 weeks after inoculation, and after symptoms were observed, infected resistant plants had a lower concentration of K, Mn, and Fe in the basal leaves than infected resistant plants. Little change in elemental concentration of susceptible plants occurred after symptoms appeared on the terminal leaves. However, due to the stunting effect of virus on susceptible plants, several elements were lower on a total accumulation basis at 2, 3, and 4 weeks after inoculation. The CMV effect on individual elements was dependent on cultivar, severity of stunting, and the number of days after inoculation leaf samples were collected.
Quantitative Chilling Enhancement and Negation in Peach Buds by High Temperatures in a Daily Cycle1
Authors: Erez A. , Couvillon G. A. , Hendershott C. H.
Published: August 2022

The effect of exposure of small peach plants (Prunus persica (L.) Batsch cvs. Redhaven and Redskin) to daily fluctuating temperatures (16 hours low: 8 hours high) of 6-15°, 6-18°, 6-21° and 6-24°C was examined in comparison with continuous chilling at 4° and a non-chilled control. Even though all chilling treatments received the same amount of chilling (weighted chilling hours), good leaf bud break was obtained only in the continuous 4°, 6-15° and 6-18° treatments. No lateral leaf buds opened in the 6-21°, 6-24° or the non-chilJed controls of both cultivars. The 6-15° temperature regime was more efficient than continuous chilling in breaking bud rest on a weighted chilling hour basis. ‘Redskin’ lateral buds were shown to have a higher chilling requirement than ‘Redhaven’. Terminal buds especially of ‘Redhaven’ showed a very low chilling requirement. Treating plants with 50 or 150 mg/liter GA3 slightly advanced bud break but did not affect the level of sprouting.
Resistance of ‘Marsh’ Grapefruit to Deformation as Affected by Picking and Handling Methods1
Authors: Rivero L. G. , Grierson W. , Soule J.
Published: August 2022

Harvesting and prepacking conditions sharply influenced subsequent resistance to deformation of ‘Marsh’ grapefruit (Citrus paradisi Macf.) when stacked fruit-on-fruit. Gently handled grapefruit kept under humid, shaded conditions until packing were far more resistant to deformation than were those roughly handled and exposed to sun and wind as too commonly occurs under commercial conditions. Loss of fruit elasticity, and hence susceptibility to permanent deformation, increased with advancing season, tending to correlate with various internal quality factors.
N Form and Concentration: Effects on N Absorption, Growth, and Total N Accumulation with Southernpeas1
Authors: Sasseville David N. , Mills Harry A.
Published: August 2022

Nitrate and absorption by southernpeas (Vigna unguiculata (L.) Walp.) during the growth cycle was determined in solution culture at 7-day intervals. Dry weight and total mg of N for each plant part were determined at bloom initiation, pod initiation, and seed maturity. When the N concentration was deficient virtually all of the was absorbed by southernpea plants from the 3rd week until harvest. At sufficient N concentrations a single peak uptake period occurred in the growth cycle prior to bloom initiation. Nitrate absorption predominated when constituted 50% or more of the N form at both N concentrations. Ammonium had either 1, 2 or 3 absorption peaks depending upon its relative concentration with . The first absorption peak was the largest and coincided with the growth cycle just prior to bloom initiation. Dry weight and N accumulation were greatest prior to bloom initiation. Subsequent accumulation occurred primarily in the seed. A reduction in N content and dry weight in the vegetative portions, particularly the leaves, coincided with the accumulation of N and dry weight in the seeds. Use of total mg of N in the vegetative tissue as a means of indicating the N status of the plant and subsequent yield was not accurate.
Temperature Measurements, Survival, and Growth of Container-grown Ornamentals, Overwintered Unprotected, in Nursery Shelters and under Microfoam Thermo-blankets1
Authors: Gouin F. R. , Link C. B.
Published: August 2022

Ilex crenata Thumb. (Japanese holly), Buxus sempervirens L. (American boxwood), Prunus laurocerasus L. (cherry laurel) and Cotoneaster congestus Bak. (dense cotoneaster) plants overwintered under the microfoam thermo-blanket survived the winter of 1976-77 better and grew larger the following growing season than plants stored unprotected or overwintered in shall shelters covered with white poly. Irrigating plants at 3 week intervals in shelters during winter storage did not improve plant survival. Plants stored unprotected suffered the greatest amount of winter injury. Soil temperatures under the microfoam thermo-blanket were consistently higher during the coldest part of winter than in all other treatments. Air temperatures under the thermo-blanket fluctuated the least initially until mid-February, but began to fluctuate more as days grew longer and ambient air temperature increased in late winter.
Set and Growth of Annona cherimola Mill. Fruit Obtained by Hand-pollination and Chemical Treatments1
Authors: Saavedra E.
Published: August 2022

Concentrations from 50 to 1,600 ppm gibberellic acid (GA3) 20 to 100 ppm naphthaleneacetic acid (NAA) and 500 ppm 6-benzylamino purine (BA) were sprayed either once on cherimoya (Annona cherimola Mill.) flowers in anthesis or 5 times on fruits at 3-week intervals commencing with anthesis to study their use as growth promotors. Only GA3 significatively enhanced fruit set and stimulated growth of seedless fruit. No synergism was found between GA3 and NAA and BA was antagonistic to GA3 relative to fruit set. Growth curves followed a double sigmoid pattern for fruits treated both naturally and chemically. GA3 induced severe cracks on fruits before harvest which makes its application impossible for practical purposes at the present state of this investigation. Cracking was not related with differential growth rates induced by hormonal treatment or absence of seeds. A possible role of GA3 on the determination of the secondary wall pattern, as observed on fruit stalk tissues, is suggested as one of the causes contributing to fruit cracking.
Reproductive Responses of Heat-tolerant Tomatoes to High Temperatures1
Authors: El Ahmadi A. Beshir , Stevens M. Allen
Published: August 2022

High-temperature responses of heat-tolerant tomato (Lycopersicon esculentum Mill. cvs. Saladette, PI 262934, BL6807, S6916, CIAS161, and VF36) were studied at 38/27°C day/night temperature. Flower production was reduced in all cultivars except BL6807 which partitioned a greater proportion of total assimilates to the flowers. Only ‘Saladette’ and VF36 showed a total lack of stigma exsertion, which in effect is functional male sterility. Pollen production was reduced in all cultivars, and there was a lack of pollen dehiscence. Several techniques were used to evaluate gamete viability. There was poor agreement among the 3 methods used to assess pollen viability. ‘Saladette’ suffered the least reduction for in vitro germination but had the greatest loss in seed set when high-temperature pollen was used. Seed set is probably the most reliable method to measure gamete viability. CIAS 161 and S6916 had the least reduction in pollen viability according to seed set criteria. Ovule viability is much more difficult to adequately evaluate. According to seed set criteria PI 262934 ovules suffered the least damage due to high temperatures. Whether the male or female gamete was affected more severely depended on genotype. Pollen viability was greatly reduced in PI 262934 but ovule viability was less severely affected. In BL6807 ovule viability was more severely reduced than pollen viability.
Weed Control in ‘Concord’ Grapes in Arkansas1
Authors: Kennedy J. M. , Talbert R. E. , Morris J. R.
Published: August 2022

Midsummer grapehoeing following spring application of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] or simazine [2-chloro-4,6-bis(ethylamino)-s-triazine] plus paraquat (1,1’-dimethyl-4,4’-bipyridinium ion) adequately controlled weeds growing in grapes (Vitis labrusca L.). When grapehoeing was used to control grape root borer [(Vitacea polistiformis Harris) lower initial rates of preemergence herbicide could be used. An additional half-rate of herbicide was required after grapehoeing to maintain weed control through the fall. Plots not grapehoed were almost completely weed free following a glyphosate [N-(phosphonomethyl)glycine] treatment. Injury to grapes the following spring was associated with fall glyphosate applications where low hanging foliage, that had not been removed, intercepted the spray. Glyphosate was most effective and paraquat more effective than dinoseb (2-sec-buty1-4,6-dinitrophenol) plus diesel fuel for postemergence control of weeds in grapes. Preemergence herbicides, napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide], norflurazon [4-chloro-5-(methylamino)-2-(α,α,α-trifluoro-m-tolyl)-3(2H)-pyridazinone], oxadiazon [2-tert-buty1-4-(2,4-dichloro-5-isopropoxyphenyl)-∆2-l,3,4-oxadiazolin-5-one], oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide), and oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene], were effective as residual type treatments.
Barrenberry Control in Lowbush Blueberry Fields through Selective Application of 2,4-D and Glyphosate1
Authors: Yarborough David E. , Ismail Amr A.
Published: August 2022

Effects of selective contact application of 2,4-dichlorophenoxyacetic acid (2,4-D) or N-phosphonomethylglycine (glyphosate) on a mixed stand of blueberry (Vaccinium angustifolium Ait.) and barrenberry (Aronia melanocarpa (Michx.) Ell.) were studied using a selective herbicide applicator. The greater height of barrenberry in its second year of growth provided the selectivity. Herbicide application on the burn year reduced both blueberry and barrenberry plant stands. Selective application of glyphosate or 2,4-D reduced the number of barrenberry plants without seriously affecting blueberry plant stem length or fruit bud number when applied to crop year plants after harvest. Higher rates of herbicides resulted in a greater reduction in barrenberry plant stand. Glyphosate or 2,4-D provided adequate control of regrowth of black barrenberry plants in lowbush blueberry fields.
The Dormancy Status of Apple Buds as Determined by an In Vitro Culture System1
Authors: Borkowska Bozena , Powell L. E.
Published: August 2022

Single axillary bud explants of apple (Malus domestica Borkh.) were removed from ‘Antonovka’ seedlings or from ‘Delicious’ trees budded on seedling rootstocks, and cultured aseptically under controlled conditions. Many excised buds grew, even though similar buds on intact resting trees did not. Chilling excised buds of ‘Antonovka’ seedlings for 2 weeks in vitro did not increase the number of bursting buds, but promoted shoot elongation on some dates. Chilling ‘Delicious’ trees for 6 and 8 weeks before excising buds promoted both bud burst and shoot elongation. A substantial number of buds excised from ‘Delicious’ trees chilled for as long as 21 weeks did not burst, suggesting other limiting factors.
Identification of Deformation Parameters and Fruit Response to Mechanical Damage in Sweet Cherry1
Authors: Lidster P. D. , Tung M. A.
Published: August 2022

The incidence of surface pitting and bruises in sweet charries (Prunus avium L. cv. Van) increased with distance of free fall. Mature fruit developed less surface pitting but developed more flattened bruises than less mature fruit in response to impact forces. Increased impact force applied to fruit resulted in a decrease in titratable acidity after storage. Fruit firmness and bioyield determined after storage increased to a maximum with the height of free fall of 45 cm for the intermediate fruit maturity only. Fruit contact with rough surfaces resulted in a significantly higher incidence of surface pitting than in fruit damaged by smooth surfaces.
Fruit Set and Development of Seeded and Seedless Tomato Fruits under Diverse Regimes of Temperature and Pollination1
Authors: Rylski Irena
Published: August 2022

Fruit set and fruit development of seeded, naturally seedless, and growth-regulator-induced seedless tomatoes (Lycopersicon esculentum Mill. cv. Azes), were examined under 17°, 22° and 27°C day temperatures, all with natural daylight and constant 10° night temperature. The best seeded fruit set and development were at 22° day temperature. A high positive correlation (r = 0.9) was found between number of seeds per fruit and fruit size with a day temperature of 27°; there was a lower but still positive correlation with lower temperature. Seedless fruit developed, and attained marketable weight (above 40 g), only when the inflorescences had been sprayed with 20% β naphthoxyacetic acid (B-NOA). Day temperature also affected fruit shape. At 27° the fruit was almost globe-shaped, but at the lower temperatures the fruit became more oblate. Fruit puffiness was particularly related to lack of fertilization resulting from flower emasculation or to lower day temperature affecting set of seed-deficient fruits. “No-Seed” treatment led to green jelly production and pointed blossom-end in fruits, under all temperature regimes.
Influence of Photoperiod and Daminozide Stock Plant Pretreatments on Ethylene and CO2 Levels and Callus Formation from Dahlia Leaf Segment Cultures1
Authors: Gavinlertvatana P. , Read Paul E. , Wilkins H. F. , Heins R.
Published: August 2022

Ethylene (C2H4) and CO2 levels and callus formation were influenced by photoperiods (8 hours-SD; 16 hours-LD) under which ‘Nita’ dahlia stock plants were grown and leaf segments incubated in vitro. Larger callus and higher levels of C2H4 and CO2 were detected when tissues from stock plants under SD were incubated under SD (SD-SD) than when incubated under LD (SD-LD). Tissue under LD-LD or LD-SD formed similar amounts of callus to SD-LD cultures, but C2H4 and CO2 levels were higher. Compared to water-sprayed controls, 2500 mg/liter butanedioic acid mono-(2,2-dimethylhydrazide) (daminozide) sprayed on SD stock plants one day before explant removal promoted callus formation, and C2H4 and CO2 production in tissue incubated under either SD or LD. Daminozide sprayed on LD stock plants had no influence on callus or C2H4, but CO2 was increased under SD or LD incubation.
Some Physiological Effects of Delaying Deterioration of Citrus Fruits by Individual Seal Packaging in High Density Polyethylene Film1
Authors: Ben-Yehoshua S. , Kobiler Ilana , Shapiro B.
Published: August 2022

Seal-packaging of individual fruits of ‘Shamouti’ and ‘Valencia’ oranges (Citrus sinensis L. Osbeck), grapefruit (C. paradisi Macf cv. Marsh) and lemons (C. limon Burm. f. cv. Eureka) with a film of high-density polyethylene (0.01 mm) markedly delayed their deterioration as measured by peel shrinkage, softening, deformation and loss of flavor. This film was applied to fruit that had received conventional treatments of disinfection with sodium orthophenylphenate and waxing. Sealed fruit maintained their fresh appearance more than twice as long as conventionally handled fruit. Weight loss of fruit was reduced about five-fold. Sealed fruit at 20° were firmer and lost less weight than non-sealed fruit at the lowest optimal temperature. Sealing various citrus fruits in high density polyethylene reduced both their respiratory activity and ethylene production. CO2 and O2 content in the internal atmosphere of the sealed and control fruit were similar but ethylene content was lower in the sealed fruit.
Quantitative Relation of Bush Snap Bean (Phaseolus vulgaris L.) Yields to Plant Population Density1
Authors: Stang J. R. , Mack H. J. , Rowe K. E.
Published: August 2022

The yield-plant density relationships of 5 bush snap bean cultivars and the effect of rate of N application on the yield-density relationship of a single cultivar were studied in 2 separate experiments. Responses were described by the equation W-θ = α + βρ where W is the pod weight per plant, ρ is the plant population density, and θ, α and β are constants. The θ, α and β values were tested for significant differences among the cultivars and levels of N. In experiment 1, θ = 0.836 was acceptable for all 5 cultivars and in experiment 2, θ = 0.897 was acceptable for the 3 rates of N. Values of θ were similar to those found for bush snap beans by other researchers. Significant differences existed among both α and β values of the cultivars. In the N experiment, α was constant but values of β differed significantly and were inversely related to the level of N. Optimum plant density was dependent on the cultivar and increased with the level of N.
Variation of Tobacco Mosaic Virus Resistance in Tomato Breeding Lines1
Authors: Kwaje S. L. , Young R. J. , Schubert O. E.
Published: August 2022

The Tm-2a gene and probably the Tm-2 gene, both of which confer resistance to tobacco mosaic virus (TMV), were used to develop fresh-market type red tomato (Lycopersicon esculentum Mill.) lines. Crosses were made between lines carrying these genes and susceptible fresh-market type tomato cultivars. Progenies were screened for resistance to TMV by inoculating with 5 known Ohio strains and inheritance was studied at 17° and 28°C. The highest level of resistance to all virus strains was obtained when the 2 resistant genes were combined in a single cross.
Organic Acids in Grapefruit Fruit Tissues
Authors: Monselise Shaul P. , Galily David
Published: August 2022

Organic acid components of tissues of grapefruit (Citrus paradisi Macf.) were analyzed by gas-liquid chromatography. At harvest, in autumn, malic acid was the main component of the flavedo (78% of total acid content), with malonic, adipic, citric, succinic and oxalic, ranging in order from 11% to 2%. In the albedo, malic was again the prevalent acid (67%), with malonic, adipic, oxalic and succinic acids ranging in order from 19% to 2%; citric acid was present in traces only. In the juice, citric was the prevalent acid (87%), malic attained 12% while other acids were present only in minute amounts. Malic, malonic, adipic and succinic acids in the flavedo declined when the fruit was left on the tree but increased during off-tree storage. Oxalic acid disappeared from the flavedo during storage. Orange and grapefruit acids are compared.
Influences of Polyethylene-Coated Paper Mulch on Soil Environment1
Authors: Liptay A. M. , Tiessen H.
Published: August 2022

The effectiveness of polyethylene-coated paper mulches in altering soil environment was investigated. The increase in maximum daily soil temperatures under mulch compared to bare soil was approximately the same for a clear polyethylene laminated on black paper as the clear polyethylene alone. Minimum daily soil temperatures were higher under laminated paper mulch than under black polyethylene. Polyethylene coated paper was as effective as polyethylene in reducing soil moisture evaporation. Studies of bulk density indicated that soils under all mulches were less compacted than the bare soil. Nitrate N levels under mulches were also higher than in the bare soil. The disposal problem encountered with polyethylene mulches at the end of the growing season is eliminated by the use of polyethylene coated paper mulches because the very thin coating of polyethylene disintegrates during the growing season, and the residual paper decomposes in the soil after tilling.
Simulated Mechanical Damage to Garden Beans During Germination1
Authors: Pollock B. M. , Manalo J. R.
Published: August 2022

Seeds otherwise free from mechanical breakage may be subjected to stress during a germination test to give symptoms of mechanical damage typical of those resulting from harvesting and cleaning machinery. This physiological breakage occurs when seeds at low moisture levels are imbibed in a wet germination medium, and is an artifact of the testing procedure. It is not clear whether the potential susceptibility to such damage should be considered as a factor in planting quality.
Greenhouse and Field Tests for Determining the Resistance of Onion Lines to Fusarium Basal Rot1
Authors: Retig Nira , Kust A. F. , Gabelman W. H.
Published: August 2022

A greenhouse method was developed for testing the resistance of onion lines to Fusarium basal rot. Roots of onion seedlings at the first true leaf stage were dipped in a heavy suspension of the pathogen. The seedlings were then planted in silica sand and grown at a soil temperature of 24° C. The first disease symptoms in a susceptible progeny appeared in about 10 days and continued to appear for up to 10 to 14 days thereafter. Infected seedlings died or were severely stunted in growth. Resistant seedlings exhibited no disease symptoms.

Field tests were conducted on muck soil known to be heavily infested with the Fusarium organism. Counts of infected plants were taken during the growing season and at harvest time. All bulbs which did not show disease symptoms were then put in cold storage for 4 months. A considerable number of bulbs which appeared to be uninfected at harvest time showed the typical decay after storage. After storage, infected and non-infected bulbs were counted and a total per cent infected was calculated.

A high positive correlation existed between greenhouse and field results.
A Bud-Graft Incompatibility in Rosa1
Authors: Buck Griffith J. , Heppel Bunny J.
Published: August 2022

A study of the histology of the bud-graft unions involving a rose cultivar, Rosa × ‘Fire King’ and two rose understocks, R. multiflora, ‘Brooks’ and R. × ‘Manetti’, was made. These 2 combinations produce a growth phenomenon termed “brittleness”. The graft unions were characterized by large quantities of fragments of necrotic material in the understock-scion interface and delay in the reconstruction of the cambial cylinder with a corresponding decrease in thickness of the cylinders of cambial derivatives derived as a result of cambial activity.
A Method of Estimating the Potential Yield of a Vegetable Crop Obtainable in a Single Harvest1
Authors: Davis R. M. , Fildes R. , Baker G. A. , Zahara M. , May D. M. , Tyler K. B.
Published: August 2022

A table is presented from which the percentage distribution of a crop into various maturity classes can be estimated for an optimizing or non-optimizing harvest day. Two or three characteristics of the crop must be known or guessed for predictive or speculative purposes. The use of the table throws light on the type of information which must be at hand in order to work intelligently toward a once-over harvest in those perishable crops which at present are not well adapted for it.
Effect of Succinamic Acid, 2-2-Dimethyl Hydrazide and Late-Season Night Temperature on the Maturity Indices of ‘Stayman’ Apples1
Authors: Albrigo L. G. , Childers N. F.
Published: August 2022

The effects of succinamic acid, 2-2-dimethyl hydrazide (Alar) and controlled late-season night temperatures on maturity indices of the sun-exposed and shaded sides of ‘Stayman’ apples were studied. The inhibitory effects of Alar on maturity were apparently reduced by warmer night temperatures. Warmer nights decreased soluble solids and red color but increased softening and acidity. These effects are attributed to an increased night respiration rate. Maturity indices data suggest that metabolic activities of the sun-exposed and shaded sides of the fruit respond differentially to increases in night temperature.
Peach Cultivar Responses to Fruit Thinning with CPA1
Authors: Bausher Michael G. , Christ Ernest G. , Childers Norman F.
Published: August 2022

Chemical thinning of peaches was conducted under orchard conditions using CPA,3 followed by standard hand thinning, on the cultivars ‘Jerseyqueen,’ ‘Sunhigh,’ ‘Redhaven’, ‘Sunqueen’ and ‘Rio Oso Gem.‘ Timing of the 3 sprays at 150 ppm was based on the water volume displacement of 100 fruits selected at random from each plot: a) at 200 ml displacement, b) at 280 ml, and c) at 280 ml plus 4 days. The control was hand thinned only. Ovule length was measured at each spray timing and found to be 7–10 mm at the 280 ml water displacement; both ovule length and water displacement techniques were used to time CPA sprays in over 2000 acres of New Jersey orchards in 1968.

Timing of the CPA thinner for optimum effectiveness in this experiment varied with cultivar. Individual fruit weight was greater on CPA-thinned trees than on the controls for the cultivars ‘Redhaven,’ ‘Rio Oso Gem,’ ‘Sunqueen’ and ‘Sunhigh’ at harvest. Chemically thinned ‘Jerseyqueen’ did not show an increased mean fruit weight at harvest. Yield reductions occurred on ‘Sunhigh’ at the 280 ml timing and on ‘Redhaven’ at the 280 ml + 4 days timing, due apparently to subsequent over-thinning by hand. Shading increased the thinning effectiveness of CPA on all cultivars. ‘Jerseyqueen’ and ‘Redhaven’ were difficult to thin with CPA under the conditions of this experiment. ‘Rio Oso Gem’ was moderately difficult, while ‘Sunhigh’ and ‘Sunqueen’ were thinned readily.
Consistency of Intercellular Space in 4 Sweet Potato Cultivars at Harvest1
Authors: Pope D. T. , Kushman L. J. , Monroe R. J.
Published: August 2022

‘Nugget’, ‘Gem’, ‘Goldrush’ and ‘Centennial’ sweet potato cultivars were grown for 3 yr at 3 locations in North Carolina. Root samples were collected at peak harvest (about October 1) each year and examined for intercellular space (IS). At 1 location each year a collection was made 3 wk prior to peak harvest, at peak harvest, and 3 wk after peak harvest. Cultivars differed significantly from one another in IS at harvest and averaged 6.26, 7.32, 8.41 and 9.85 ml/100 ml of root for ‘Nugget’, ‘Gem’, ‘Goldrush’ and ‘Centennial’, respectively. Over the 3-yr period IS did not differ significantly due to location, time of harvest, or years.