bluuebunny/crossref_metadata_2025 huggingface dataset:
Developmental Responses of Zinnia to Photoperiod
Authors: Boyle Thomas H. , Stimart Dennis P.
Published: August 2022

Zinnia elegans Jacq. ‘Carved Ivory’, ‘Cherry Ruffles’, and ‘Rosy Future’ were grown under short days (SD) or long days (LD) to determine the effect of photoperiod on flower initiation and morphological development. Plants grown under LD (14, 16, 18, or 24 hours) were greater in height, leaf size, flower diameter, and node number and flowered later compared to plants grown under SD (8, 10, or 12 hours). The greatest increases in plant responses occurred between 12- and 14-hour treatments. Supplemental irradiation (day continuation, night break, and predawn lighting) resulted in LD responses but did not equally affect days to flowering, stem diameter, or node number. Height and ray petal number were greatest for all cultivars under day continuation and flower diameter was largest under day continuation and predawn lighting. More LD before SD resulted in increases in height, stem and flower diameter, node number, ray petal number, and days to flowering, indicating a cumulative effect of LD on morphological development. Results demonstrate that Z. elegans is a facultative SD plant for floral initiation and development and that photoperiodic responses vary between genotypes.
Root Regeneration of Liriodendron tulipifera in Response to Auxin, Stem Pruning, and Environmental Conditions
Authors: Kelly R.J. , Moser B.C.
Published: August 2022

Root regeneration of tulip tree (Liriodendron tulipifera L.) was greater when seedlings were transplanted in the spring than in the fall. Indolebutyric acid–potassium salt (IBA) applied to the roots increased root regeneration with the greatest response at 1000 to 3000 mg liter−1 in the spring and 3000 mg liter−1 in the fall. Root regeneration and shoot growth increased as time of chilling at 2°C prior to transplanting increased from 0 to 1680 hours; 1008 hours satisfied the chilling requirement. Photoperiod did not directly influence root regeneration during either season. Root regeneration and shoot growth of shoot-pruned plants interacted with season, IBA treatment, and level of stem pruning. Decreasing sunlight intensity by 20%, 47%, or 74% reduced root regeneration and shoot growth. IBA improved root initiation over untreated plants at all light intensities tested, but subsequent growth of these roots decreased with decreased light.
Structure and Composition of Normal Skin (Periderm) and Wound Tissue from Cured Sweet Potatoes
Authors: Walter W.M. , Schadel W.E.
Published: August 2022

The initial response of the sweet potato [Ipomoea batatas (L.) Lam] to wounding involves deposition of a polymeric material on the inside of several layers of parenchyma cells at the site where the root’s protective periderm has been removed. Analysis of normal periderm and wound tissue indicate that the wound tissue is similar to the normal periderm with respect to aromatic components, but contains only 14% as much suberin.
Effects of Storage Procedures and Low Oxygen and Carbon Dioxide Atmospheres on Storage Quality of ‘Spartan’ Apples
Authors: Lau O.L.
Published: August 2022

‘Spartan’ apples (Malus domestica Borkh.) kept in 1.0% O2 + 2.0% CO2 at 0°C for 6–9 months were firmer and had more acids than apples kept at standard commercial atmospheres of 2.5% O2 + 2.0% CO2. The high firmness and juice acidity associated with low O2 atmospheres persisted for 7 days in 20° air. Reduction of storage CO2 from 2.0% to 0.5% appreciably decreased firmness and increased incidence of core browning and scald in fruit stored at 2.5% O2 but not in those stored at 1.0% O2. No fruit injury or increased alcohol or off-flavor production resulted from the low O2 treatments; reduction of storage O2 from 2.5% to 1.0% decreased core browning in the fruit. Fruit stored in 1.0% to 2.5% O2 with a “rapid CA” procedure were firmer than those with a “slow CA” procedure immediately after removal from the storage, but this benefit disappeared in fruit from the 1.0% and 1.5% O2 atmospheres after an additional storage period of 28 days in 0° air and 7 days in 20° air.
Antitranspirant and Root and Canopy Pruning Effects on Mechanically Transplanted Eight-year-old ‘Murcott’ Citrus Trees
Authors: Castle William S.
Published: August 2022

Two groups of 8-year-old ‘Murcott’ [Citrus reticulata Blanco × C. sinensis (L.) Osbeck hybrid?] trees on rough lemon (C. jambhiri Lush.) rootstock were transplanted with a Vermeer tree digger in March and July, respectively. Root and shoot pruning and a 2% (v/v) spray of a pinolene-based antitranspirant (Vapor Gard) formed the treatments either individually or in combination. Canopy size at transplanting had the greatest effect on tree water-stress and subsequent tree growth and yield. The antitranspirant and root pruning tended to reduce leaf water-stress, but the effects generally were small and nonsignificant. Root pruning also seemed to stimulate new root growth. After transplanting, roots grew 2 to 3 m beyond the soil ball in one year. Four years after transplanting there were virtually no differences in tree height or canopy volume. Cumulative yield was less for trees with 30% and 85% of their foliage removed as compared to those with 50% removed. Trees pruned 50% bore fruit the year after transplanting and consistently yielded more throughout the study.
The Morphology of Pistillate Flower Differentiation in Pecan
Authors: Wetzstein Hazel Y. , Sparks Darrell
Published: August 2022

Differentiation and development of the pistillate flower in pecan, [Carya illinoensis (Wang.) K. Koch] were examined using scanning electron microscopy (SEM). Floral differentiation did not occur until growth resumed in the spring, when the outer bud scales were shed and buds were swollen, but before the inner bud scale was broken. Subsequent floral and inflorescence development were correlated highly with stages of bud and early leaf development. The organogenesis of the pistillate flower was described from inception to the stage of visible inflorescence.
Effects of Rootstock and Soil Type on Pratylenchus penetrans Populations in Apple Feeder Roots
Authors: Costante J. F. , Mai W. F. , Klein R. M.
Published: August 2022

Sixteen nonbearing new and replanted ‘McIntosh’ apple (Malus domestica Borkh.) orchards were surveyed in August of 1983. Rootstock and soil type influenced the number of nematodes [Pratylenchus penetrans (Cobb 1917) Sher and Allen] found in feeder roots of the 12 two-year-old orchards (P = 0.007). Mailing Merton (MM) 111 roots in clay had fewer P. penetrans (12.4/g) than MM 106 roots in clay (42.2/g) or roots of MM 111 in loam (93.2/g). Nematode populations in feeder roots increased with soil depth down to 24 cm. P. penetrans populations were not influenced by soil pH, organic matter, drainage, root conditions, tree vigor, herbicide management, or replant status.
Effects of Calcium, Daminozide, and Fruit Maturity on Canned ‘Bing’ Sweet Cherry Quality
Authors: Drake S. R. , Proebsting E. L.
Published: August 2022

Cherries pitted prior to canning or treated with daminozide had lower drained weights, more total anthocyanin, more turbid syrup, darker Agtron red values, and were softer than nonpitted or nontreated cherries. USDA color grade was higher, but USDA character grade was reduced when cherries were pitted or treated with daminozide. CaCl2 applied as either a 3% dip prior to pitting or as a 1% addition to the syrup increased the firmness, decreased the turbidity of the syrup of pitted and nonpitted cherries, and reduced the number of split fruit in nonpitted cherries. CaCl2 improved the USDA character grade of pitted and nonpitted cherries, and daminozide-treated cherries. Delaying harvest by 8 days reduced drained weight losses, increased total anthocyanin content, pH and soluble solids, and resulted in a darker red canned cherry as measured by the Agtron. CaCl2 compensated for the reduced USDA scores for character caused by pitting or daminozide, increasing character to equal that of nonpitted or nontreated, respectively. Chemical names used: butanedioic acid mono(2,2-dimethylhydrazide) (Daminozide).
Chilling Accumulation and Rest of Sour Cherry Flower Buds
Authors: Felker Frederick C. , Robitaille Henry A.
Published: August 2022

The response of ‘Montmorency’ sour cherry (Prunus cerasus L.) flower buds to controlled chilling was determined using both cut shoots and intact trees. Chilling hours accumulated quantitatively when shoots were held at 5°C. Heat unit accumulation also occurred at 5°, whereas at 15° chilling was either nullified or buds accumulated sufficient heat units to break, depending on how many chilling hours were accumulated previously. Chilling nullification at 15° was reversible, as chilling could be reaccumulated at 5°. A daily cycle of 5°/15° for 16/8 hr, respectively, chilled buds as efficiently as did continuous 5° for the same number of total hours. Buds on entire trees in pots, and on shoots cut from the orchard immediately before forcing, responded identically to buds on control-chilled cut shoots. Differences in bud response to controlled chilling with collection date suggested that bud maturation, chilling, and heat unit accumulation overlap. Gibberellic acid was the only chemical among various putative rest-breaking agents tested that accelerated break of partially chilled buds.
Rescuing Abortive Impatiens Hybrids through Aseptic Culture of Ovules
Authors: Arisumi Toru
Published: August 2022

Aseptic culture of ovules resulted in the germination and development of abortive hybrids in 38 of 66 interspecific crosses among Impatiens. In some crosses, 6- to 11-day-old ovules had significantly higher percentages of germination than 3- to 5-day-old ovules. An average of 19.9% of the germinated seedlings was rescued, and the rest were lost through abnormal development in vitro. About 90% of the abnormal seedlings developed into hard, callus-like masses of varying sizes and shapes, and the rest developed into imperfect seedlings without roots or shoots, albinos, and soft calli. Seedlings were rescued in 25 crosses, and in 13 crosses none of the germinated seedlings was rescued. The 25 rescued progenies were derived from 8 crosses among African species, 1 among Indian species, 4 between African and Indian species, and 12 between African and New Guinea-Indonesian species. All but 2 of the progenies are new and are being reported for the 1st time. The hybrids were usually distinct and easily identified by inspection of leaves and flowers. All were sterile.
Influence of Cultivar and Flower Thinning within the Inflorescence on Competition among Olive Fruit
Authors: Rallo L. , Fernández-Escobar R.
Published: August 2022

Experiments with heavily-flowering olive trees showed only one period of abscission of flowers and fruit in the 5-6 weeks following full bloom. This abscission of flowers and fruit is responsible for the small percentage of fruit retained to maturity. Most of the fruit drop was concomitant with initial fruit growth for all cultivars. There were no differences in the number of fruit per inflorescence among cultivars, but the percentage of inflorescences with fruit at harvest was related negatively to final fruit size for each cultivar. Thinning of perfect flowers within the inflorescence did not affect fruit set at the inflorescence level; thus, the inflorescence behaved as a unit of fruitfulness. Competition among fruits played a significant role in fruit set. Initial setting induced by pollination and fertilization is counteracted early by fruit abscission originated by competition among fruit. In light of this early abscission, the use of fruit set to indicate response to pollination in previous experiments is questioned.
Production and Economic Returns of Vegetable Intercropping Systems
Authors: Brown James E. , Splittstoesser Walter E. , Gerber John M.
Published: August 2022

Cropping systems were compared among vegetable crops which are commonly grown for profit on a 5–10 ha farm. Tomato [Lycopersicon esculentum (Mill.) ‘Jet Star’], cabbage [Brassica oleracea (L.) var. capitata ‘Sunup’], collards [Brassica oleracea (L.) var. acephala ‘Vates’], and muskmelon [Cucumis melo (L.) ‘Gold Star’] were monocropped; cabbage was intercropped with tomatoes; and collards were intercropped with muskmelon. Crop yield, production cost, and economic returns of the intercrop system were comparable to those of the crops produced alone.
Relationship among Ventilation of Citrus Storage Room, Internal Fruit Atmosphere, and Fruit Quality
Authors: Waks J. , Chalutz E. , Schiffmann-Nadel Mina , Lomeniec Ella
Published: August 2022

Changes in air composition of the citrus storage atmosphere and of the internal atmosphere of the fruit as affected by the ventilation rate were studied using 1 grapefruit and 2 orange cultivars. These changes were examined in relation to fruit weight loss, ethanol content of the juice, and rot development during storage periods of up to 5 months. Rates of ventilation affected the CO2 concentrations more than the O2 levels of both the external and internal atmospheres of the fruit. In small-scale tests, ventilation rates as low as 10%·hr−1 of the empty volume of the storage space did not cause major changes in the gas composition, nor did they effect fruit quality adversely. In commercial tests, however, an increased rate of ventilation (70% to 100%·hr−1) was needed to reach similar results. On the basis of this information we recommend reducing the ventilation rate in commercial citrus storage rooms from 150% or 200%·hr−1, the rate now commonly employed, to 100%·hr−1. This reduced ventilation rate will help lower costs of refrigeration, while maintaining good fruit quality.
Production and Economic Returns of Three Vegetable Double-cropping Systems
Authors: Brown James E. , Splittstoesser Walter E. , Gerber John M.
Published: August 2022

Double-cropping systems were compared to the same vegetable monocropped. Snap beans [Phaseolus vulgaris (L.) ‘Bush Blue Lake’], sweet corn [Zea mays (L.) ‘Sundance’], cauliflower [Brassica oleracea (L.), Botrytis group, ‘Snow Crown’], summer squash [Cucurbita pepo (L.) ‘Zucchini Elite’], and broccoli [Brassica oleracea (L.), Italica group, ‘Green Comet’] were used. The double-crop systems used were spring snap bean and fall cauliflower, summer squash and fall broccoli, and spring sweet corn and fall snap beans. The monocrop system was used as a control for the double-crop systems. The greatest net returns were: 1) squash monocropped or squash/broccoli double-cropped, 2) squash double-cropped, 3) cauliflower or cauliflower/snap bean double-cropped, and 4) broccoli or cauliflower or snap beans monocropped. Fall snap beans provided the least economic return. The double-cropping system allows an option of crop production with a potential increase in yield and economic returns using half the amount of land per year required for either crop grown in monoculture. In addition, these systems reduce the risk of economic failure during a year of low-market demand for either crop grown alone.
Effect of Ethephon, Gibberellic Acid, and Maleic Hydrazide on Vegetative Growth, Flowering, and Fruiting of Cucurbitaceous Crops
Authors: Arora S.K. , Pandita M.L. , Partap P.S. , Sidhu A.S.
Published: August 2022

A study on the effect of ethephon, GA3, MH, and NAA on vegetative growth, flowering, and yield of bottle gourd [Lagenaria siceraria (Mol.) Standi.], round melon (Citrullus vulgaris ‘Fistulosus’), sponge gourd (Luffa cylindrica Roem.), summer squash (Cucurbita pepo L.), and watermelon (Citrullus lanatus Thunb. Matsum & Nakai) was conducted from 1979–1982. Maleic hydrazide applied at 150 mg/liter to bottle gourd and at 50 mg/liter to round melon, ethephon at 100 mg/liter to sponge gourd and at 250 mg/liter to summer squash, and GA3 at 25 mg/liter to watermelon were most effective in stimulating the elongation of main stem (except in summer squash), increasing branches per plant, lowering the male : female flower ratio, setting additional fruit, and producing highest fruit yield as compared to the untreated control. Chemical names used. (2-chloroethyl)phosphonic acid (ethephon); gibberellic acid (GA3); 1, 2-dihydro-3, 6-pyridazinedione (MH); 1-naphthaleneacetic acid (NAA).
Simplified Method for Rooting Apple Cultivars in Vitro
Authors: Zimmerman Richard H. , Fordham Ingrid
Published: August 2022

The article “Simplified Method for Rooting Apple Cultivars in Vitro” by Richard H. Zimmerman and Ingrid Fordham [J. Amer. Soc. Hort. Sci. 110(1):34–38. 1985.] contained errors within Table 3. The corrected table appears below. Tables 4, 5, and 6 also are being reprinted because the previously published format was difficult to read.
Weed Control Systems for Fresh Market Tomato Production on Small Farms
Authors: Teasdale John R. , Colacicco Daniel
Published: August 2022

The efficacy and economics of several weed control systems for fresh market tomato (Lycopersicon esculentum Mill. ‘Pik Red’) production were compared in a 3-year field experiment. Nearly perfect weed control for 7 weeks after transplanting was required to achieve maximum yields. The increased profits associated with maximum yields more than compensated for the additional costs required to achieve optimal weed control. Under Maryland conditions, black polyethylene mulch in combination with a pretransplant incorporated application of napropamide plus pebulate and a posttransplant directed application of paraquat plus metribuzin provided the most consistent weed control and highest profit. Other profitable treatments included black polyethylene mulch in combination with other posttransplant herbicides, or with cultivation and handweeding. Treatments without black polyethylene, including a pretransplant incorporated application of napropamide plus pebulate followed by a postransplant application of metribuzin and/or cultivation, provided good weed control but did not result in yields or profits as high as those treatments with black polyethylene in 2 out of 3 years.
Effect of Level and Duration of High Temperatures on Rest in the Peach
Authors: Couvillon Gary A. , Erez A.
Published: August 2022

Rooted ‘Redhaven’ peach [Prunus persica (L.) Batsch] cuttings were exposed to diurnal temperature cycles. A severe reduction in lateral vegetative bud break was found in plants refrigerated at 4°C and given 8 hr daily exposure to 19° (±0.1°). Nearly complete chilling negation occurred in plants exposed to diurnal cycles including 8 hr of 20° or 21°. Also, effect decreased with increased time (0 to 8 hr per day) of exposure to 24°. Buds on plants exposed to cycles including 20° for 2 and 4 hr showed no chilling negation, but gradual increases in chilling negation occurred with longer exposures to 20°. ‘Harvester’ peach plants were exposed to 2, 7, or 12 days of 23° following the accumulation of one-fourth, one-half, or three-fourths of the chilling requirement. Chilling negation occurred only with the 12-day exposure to 23° when high temperatures were applied following the accumulation of one-fourth and one-half of the chilling requirement. No chilling negation was found after 12 days’ exposure to 23° if three-fourths of the chilling requirement had accumulated before exposure.
High Temperature Effects on CO2 Gas Exchange in Heat-tolerant and Sensitive Tomatoes
Authors: Bar-Tsur A. , Rudich J. , Bravdo B.
Published: August 2022

The effect of temperature on CO2 fixation was studied in 2 tomato (Lycopersicon esculentum Mill.) cultivars; the heat-sensitive “Roma VF” and the heat-tolerant “Saladette". A decrease in apparent photosynthesis was found in both cultivars after plant exposure for various lengths of time to temperatures of 35° to 40°C. An increase in temperature also increased transpiration and raised the CO2 compensation point. The decrease in photosynthesis after a short exposure to high temperature was due to an increase in mesophyll resistance and, to a lesser extent, to an increase in stomatal resistance to CO2 diffusion. Saladette was less affected by high temperature and had a slightly greater photosynthetic capacity than the heat-sensitive Roma VF, after pretreatment at high temperature.
Quality Measurements of Carnation Treatment Solutions in Relation to Flower Silver Distribution and Longevity
Authors: Gorin N.
Published: August 2022

In the article “Quality Measurements of Carnation Treatment Solutions in Relation to Flower Silver Distribution and Longevity,” by N. Gorin et al. [Journal 110(1): 117–123. 1985], the following corrections should be noted:

Page 118. Left column, line 34, 55° should read 550°.

Page 122. Left column, 3rd part of first formula. Exponent in denominator should read 10.84 not 104.

Page 122. Left column, equation 5. et should be ct.

Page 123. Left column, line 5. The word (black) should appear below Ag2S ↓.

Table 1. The symbol before 0.93 in the left column should be > instead of <,

Table 3. The last line under the table footnotes should include three dashes (– – –), not one dash (–).

Table 4. Under the column byKI, the symbol > should appear before 0.93 with Commercial C-fresh and Commercial F.
Effects of Production Systems, Plant Populations, and Harvest Dates on Yield and Quality of Machine-harvested Strawberries
Authors: Morris J. R. , Sims C. A. , Cawthon D. L.
Published: August 2022

A study was designed to examine the effects of production systems (i.e., standard bed, wide bed, and black plastic bed), a high and low plant population, and 3 harvest dates on the machine-harvested yield and quality of 2 strawberry (Fragaria × ananassa Duch.) clones. ‘Cardinal’ produced higher yields than A-5344, but had poorer quality. The wide-bed production system produced higher yields than the other production systems and had no adverse effects on quality. ‘Cardinal’ had optimum yield when produced under a low plant population, while A-5344 had optimum yield under a high plant population. Fruit quality was maintained throughout the 5- to 7-day harvest season each year.
F1 Hybrids Obtained through the Regulation of Polyembryony by Continuous Gamma Irradiation in Citrus unshiu Cultivars
Authors: Watanabe Hiroshi
Published: August 2022

Continuous gamma irradiation was applied to the polyembryonic unifoliolate Citrus unshiu ‘Miyagawa-wase’ (Miyagawa Early), during polyembryogenesis. The number of embryos was reduced markedly in response to the irradiation dosage; however, the fertilized embryo in each seed was seldom inhibited by the irradiation treatment. Based on these results, potted young trees of 2 C. unshiu ‘Miyagawawase’ and ‘Sugiyama’ hand-pollinated with Poncirus trifoliata (L.) Raf., were placed in a gamma field (the Institute of Radiation Breeding, 60Co source) and exposed to gamma-rays at the rates of 200, 300, or 400R per day for 32 or 55 days. Seeds from irradiated fruit were sown, and leaf shape of seedlings was examined. A high percentage (85.7% to 100%) of seedlings with the trifoliolate leaf character of Poncirus, indicating they were from gametic embryos, resulted from the exposure of 200 and 300R/day for 32 days.
Structure and in Vitro Germination of the Pollen of Pecan
Authors: Wetzstein Hazel Y. , Sparks Darrell
Published: August 2022

The morphology of pecan [Carya illinoensis (Wangenh C. Koch)] pollen from 4 cultivars was examined using light and scanning electron microscopy. Pollen was triporate, paraisopolar and suboblate, with a tectate and microechinate surface. The exine was thickened around pores. Pollen from the 4 cultivars was indistinguishable. Pollen germinated in vitro after 1 hr. Pollen tubes grew from 1 or 2 pores, with one germ tube becoming dominant. Pollen germination decreased dramatically after anther dehiscence. Less than 1% of the pollen germinated 5 days after collection.
Pollen Staining and High-temperature Tolerance of Bean
Authors: Weaver M. L. , Timm H. , Silbernagel M. J. , Burke D. W.
Published: August 2022

Viability of pollen grains of isogenic sibling bean (Phaseolus vulgaris L.) selections of known tolerance of sensitivity to high temperatures (HT), as previously determined by pod retention and seed yield, was compared to that of a common parent bean selection and a cowpea [Vigna unguiculata (L.) Walp.] cultivar. Exposure of newly opened flowers to temperatures of 35° or 41°C reduced the viability of pollen grains in all bean selections. Pollen of all sibling selections was less affected by HT than pollen of their common parent suggesting transgressive segregation of factors for HT tolerance. At 41°, most pollen grains were destroyed in the parent bean selection and the 2 HT-sensitive siblings, whereas 44% to 55% of the pollen grains appeared to be viable in the 2 HT-tolerant siblings. Pollen viability of the HT-tolerant cowpea cultivar was not reduced by temperatures to 41°. Pollen staining indicated an interrelationship between pollen viability and tolerance to HT stress among the bean selections. The technique described has the potential for rapid selection of HT-tolerant genotypes in hybrid populations.
Translocation and Metabolism of Cytokinin in Cut Carnations
Authors: Kelly John W. , Staby George L. , Chism Grady W.
Published: August 2022

When silver thiosulfate (STS), an antiethylene agent, was used prior to a preservative holding solution for carnations (Dianthus caryophyllus L.), there was no benefit in using the cytokinin benzyladenine (BA). If no STS or preservative was used, BA extended longevity. Most of the BA applied to the cut carnation remained localized in stem tissue. Stem, petal, gynoecium, and leaf tissue all metabolized BA. The applied BA levels increased in the gynoecium during carnation senescence, but STS prevented this increase. It is likely that STS altered the source:sink relationship between petals and gynoecium, since movement of cytokinin into the gynoecium corresponded to increased gynoecium fresh weight.
Mite Responses and Trichome Characters in a Full-Sib F2 Family of Lycopersicon esculentum × L. hirsutum
Authors: Carter Catherine D. , Snyder John C.
Published: August 2022

A full-sib family of F2 individuals from a cross between mite-susceptible Lycopersicon esculentum Mill and mite-resistant Lycopersicon hirsutum Humb and Bonpl. was assayed for trichome characters and resistance to spider mites (Tetranychus urticae Koch). Mite responses primarily were associated with density of the Type IV trichome and, to a much less degree, with the leaflet surface bioassayed and phenol content of the Type VI trichome tip. Mite survival on F2 hybrids with at least 5.6 Type IV trichomes per mm2 was comparable to that on L. hirsutum.
Influence of Light Duration and Irradiance on Micropropagation of a Hardy Deciduous Azalea
Authors: Economou Athanasios S. , Read Paul E.
Published: August 2022

Shoots harvested from the first and 2nd reculture of azalea (Rhododendron sp.) accession 800374 shoot tip cultures grown under 16 hr photoperiod from cool-white fluorescent light were taller and achieved higher quality ratings than shoots from 24 hr daily photoperiod. The number of shoots produced during the first reculture was the same for both 16 and 24 hr photoperiod, whereas significantly more shoots were harvested from cultures grown under 16 hr in the 2nd reculture. Similarly, 24 hr light inhibited elongation of shoots and decreased quality rating from in vitro-derived shoot cultures without any effect on the number of shoots per culture. Photosynthetic photon flux density (PPFD) of 30 and 75 μmol s−1m−2 (400–700 nm) increased number, length, and quality rating of shoots harvested from in vitro-derived shoot explants when compared to a 10 μmol s−1m−2 PPFD. However, recultured in vitro-derived shoot explants produced similar number and length of shoots under 10, 30, and 75 μmol s-1m-2, whereas the quality rating was reduced in cultures under 75 μmol s−1m−2. The highest percentage of rooting occurred in microcuttings harvested from cultures grown under 10 and the lowest under 75 μmol s−1m−2. Increasing the PPFD from 10 to 75 μmol s−1m−2 reduced shoot length and quality rating of rooted microcuttings, as well as root length and quality rating.
Comparison of Three Methods for Determining the Floral or Vegetative Status of Strawberry Plants
Authors: Durner Edward F. , Poling E. Barclay
Published: August 2022

In the article “Comparison of Three Methods for Determining the Floral or Vegetative Status of Strawberry Plants” by Edward F. Dumer and E. Barclay Poling [Journal 110(6):808–811, Nov. 1985], the Fig. 2 caption was incorrect. The correct caption should read: Representative central longitudinal section of A. Questionable meristem (bar = 10 μ), B. Vegetative apex (bar = 10 μ), and C. Reproductive meristems (bar = 20 μ).
Effect of Shoot Density and Crop Control on Growth, Yield, Fruit Composition, and Wine Quality of ‘Seyval blanc’ Grapes
Authors: Reynolds Andrew G. , Pool Robert M. , Mattick Leonard R.
Published: August 2022

A factorialized thinning level/shoot density experiment which was started in 1980 demonstrated that ‘Seyval blanc’ grapes benefits from cluster thinning in terms of vine size maintenance, cane ripening, berry weight, and Brix. Reducing shoot density led to increased cane ripening. Concomitant increases in cluster exposure improved fruit composition and led to higher berry weights. However, maintaining reasonably high shoot densities (4 shoots/30 cm of row or more) also was essential to maintain yield and vine size, even when crop was controlled by thinning. Levels of 4 shoots/30 cm of row and 17 clusters/500 g cane prunings are recommended to maximize yield and maintain reasonable fruit quality and vine size. Postbloom cluster thinning was found to reduce the incidence of bunch rot and to reduce the production of 2nd crop in 1982, without affecting any parameters of yield or fruit composition.
Simulated Spotted Tentiform Leafminer Injury and its Influence on Growth and Fruiting of Apple Trees
Authors: Kappel Frank , Proctor J. T.A.
Published: August 2022

Defoliation (0%, 25%, 50%, 75%, or 100% leaves removed) of apple trees (Malus domestica Borkh.) to simulate loss in photosynthetic area caused by spotted tentiform leafminer (Phyllonorycter blancardella F.) reduced trunk cross-sectional area, yield, and fruiting the following year. Shoot growth responded the year of injury and the following year. Fruit size and maturity also were affected. Punching holes (0, 2, 4, 8 simulated mines of 0.56. cm2) into leaves of mature fruiting trees had no effect on vegetative growth. Fruiting may have been reduced. Leaf punching reduced rootstock growth of small potted apple trees.
Sugar Content and Uptake in the Strawberry Fruit
Authors: Forney Charles F. , Patrick J. Breen
Published: August 2022

Sucrose was not detected in developing fruit of ‘Brighton’ strawberry (Fragaria × ananassa Duch.) until 10 days after anthesis. Thereafter, its concentration increased rapidly but then declined as fruit became red ripe. The concentration of glucose and fructose were similar and higher than that of sucrose during early fruit growth and in ripe fruit. Uptake of 14C-sugars was followed in excised disks of cortical tissue from fruit 15–17 days old. The addition of CaCl2 was necessary to maintain tissue respiration. Sucrose uptake into tissue disks was nearly constant over 4 hr and had a pH optimum of 5.0. Kinetic analysis of sucrose uptake revealed both linear and saturable components. The kinetic characteristics of fructose uptake was similar to those for sucrose. Glucose, however, was taken up much more rapidly than either sucrose or fructose and only demonstrated saturation kinetics. The metabolic inhibitors NaCN (5 mM), dinitrophenol (DNP, 3 Mm) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP, 100 μM) stimulated sucrose uptake 34%, 94%, and 54%, respectively. DNP eliminated the saturable component. Uptake of sucrose was inhibited by 36% with 10 μm DNP, 16% with 5 mM glucose, and 16% in a 100% N2 atmosphere. After incubation in 14C-sugars for 2 hr, about 90% of the label recovered from disks was in a neutral fraction. Half or more of this was in either glucose or fructose, depending upon the sugar fed. The distribution of 14C between glucose and fructose moieties of sucrose isolated from tissue fed (14C-fructosyl) sucrose indicated that a portion of the sucrose recovered underwent hydrolysis and randomization. Similar results were found with sucrose isolated from attached, whole fruit 8 hr after abraded leaves were fed labeled sugars. Results suggest that sucrose may be hydrolized prior to uptake into fruit tissue.
Minimum Fluorescent Light Requirements and Ancymidol Interactions on the Growth of Easter Lily
Authors: Wilkins H.F. , Grueber K. , Healy W. , Pemberton H.B.
Published: August 2022

Easter lily (Lilium longiflorum Thumb. ‘Nellie White’) bulbs forced under an 8-hr duration of fluorescent light at 400 μmol·s−1·m−2 were acceptable for commercial sales. The total number of flowers initiated were not influenced by light intensity or duration during forcing. The number of flowers reaching anthesis was influenced by light duration. Ancymidol was effective in reducing internode elongation.
Rates of Change in Firmness, Acidity, and Ethylene Production of ‘McIntosh’ Apples in Simulated Low-ethylene CA Storage
Authors: Liu F.W. , Samelson D.
Published: August 2022

‘McIntosh’ apples (Malus domestica Bork.) sprayed with 1000 or 2000 mg−1 liter−1 daminozide were stored in simulated low-ethylene controlled atmosphere (CA) storage for 7.5 and 9.5 months in 3 consecutive years. The simulated CA was a flow-through system with 2.5–3% O2, 3–5% CO2, <1 μ1·liter−1 ethylene, 2.2° to 3.3°C, and 90–95% relative humidity. A maturity index based on the date of the onset of autocatalytic ethylene production (AEP) of apples not sprayed with daminozide was used. ‘McIntosh’ apples, which were harvested within 10 days after the onset of AEP, lost <10% of their original firmness, 27–29% of acidity, and 0% of soluble solids after 7.5 months of storage. The rates of ethylene production of these apples were very low in the first 4 months, gradually increased thereafter, but remained <0.5 μl·kg−1·hr−1 for at least 7 months. The low-ethylene CA effectively preserved the quality and inhibited the ethylene production of ‘McIntosh’ apples. Chemical name used: butanedioic acid mono(2,2-dimethylhydrazide) (daminozide).
Equivalent Stress Comparisons Among Tomato Strains Differentially Tolerant to Phosphorus Deficiency
Authors: Coltman R.R. , Gerloff G.C. , Gabelman W.H.
Published: August 2022

Physiological and morphological features of tomato (Lycopersicon esculentum Mill.) strains differentially adapted to phosphorus (P) deficiency differed depending on whether the strains had been grown under a single level of low P in screening experiments or under specific levels of P that reduced growth of each of the strains to about 50% of maximum, i.e., at “equivalent stress”. These differences indicated that stress compensation contributed significantly to the physiological and morphological phenotypes of strains under the specific P level used for screening for low-P tolerance. Consequently, the true extent of genetic differences for these traits was not directly measurable. Differences between strains for root:shoot ratios, internal-P-use ratios, and kinetic parameters of P uptake still were observed at equivalent stress. Thus, the genetic bases of these differences seem secure. The P concentration in lower leaves of tolerant strains was lower than in intolerant strains, and the maximum rates of 32P by uptake excised roots were increased in the tolerant strains.
The Relationship of Ethylene and Ethane Production to Tissue Damage in Frozen Rhododendron Leaf Disks
Authors: Harber R.M. , Fuchigami L.H.
Published: August 2022

Ethylene and ethane production of freeze-stressed rhododendron (Rhododendron sp. ‘Sappho’) leaf disks were compared to visual rating, TTC reduction, and electrolyte leakage as possible means of measuring tissue viability. Ethane production, as caused by freezing temperatures, was highly correlated with visual rating, TTC reduction, and electrical conductivity (r = 0.96, r = −0.81, and r = 0.96, respectively). Ethylene production peaked concurrently with initial stages of visual tissue damage, then decreased as the temperature was lowered until complete death occured. Ethane production and electrolyte leakage peaked coincidentally with the decrease of ethylene. Ethylene:ethane ratios are suggested as a measurement of freeze-induced tissue damage. This study supports the view that ethylene production is related to stress and ethane production to cell death. Chemical names used: 2,3,5-triphenyltetrazolium chloride (TTC).
Influence of Seed Harvesting and Handling Procedures on Germination of Cucumber Seeds
Authors: Edwards M.D. , Lower R.L. , Staub J.E.
Published: August 2022

Three cucumber (Cucumis sativus L.) populations were evaluated to determine the effects of several seed harvesting and handling procedures on seed quality. Fruit maturity at seed harvest, fermentation duration in seed extraction, seed storage time, and germination temperature all significantly influenced germination percentage and rate. About 30% of the observed variation in germination percentage was due to interactions between handling factors rather than to main effects of factors. Although germination in excess of 90% was observed for some combinations of factors with as little as 28 days of fruit maturity (post-pollination), the advantages of greater seed maturity at harvest were evident for rate of germination and tolerance to long fermentation times. Positive responses to short fermentation durations (≤4 days) occasionally were observed, but longer fermentation durations were markedly deleterious under some conditions. Six months of seed storage were effective in improving germination of seed at 15° and 20°C, but had little effect on germination at 25°. The 3 cucumber populations were markedly different in response to some seed handling factors.
31P-NMR Monitoring of Ethephon Decomposition in Olive Leaves
Authors: Lang Gregory A. , Martin George C.
Published: August 2022

The possibility of using 31P-nuclear magnetic resonance (NMR) spectroscopy to detect ethephon (ET) in olive leaves has been examined. 31P-NMR spectroscopy can be used as a nondestructive technique (tissues excised but not extracted) with the unique attributes of monitoring ET hydrolysis internally and without radiochemicals. A characteristic spectral peak for the parent ET molecule was found 17-21 ppm (a measure of relative frequency, not concentration) downfield from the H3PO4 reference, and a nonreactive, minor contaminant spectral peak was found at 26-27 ppm. Absolute spectral peak location (“chemical shift”) is pH-dependent. The ET hydrolysis product, orthophosphate, produces a spectral peak at 2 to 3 ppm, which coincides with the broad spectral peak attributed to major endogenous phosphate compounds in leaves, such as inorganic phosphate. The lower limit of 31P-NMR detection of ET in solution was 10−3 m; however, spray applications of ET were not detectable in olive leaves unless concentrations of 5 × 10−2 m or more were used, which is far greater than current agricultural use levels for mechanical harvest of olive. Nevertheless, 31P-NMR spectroscopy was useful in following ET uptake and decomposition for more than 48 hr in olive leaves from xylem-fed shoots, and the resolution of the ET spectral peak into separate, adjoining peaks presents the potential to identify and quantify subcellular compartmentalization of ET according to pH-induced chemical shifts. Such knowledge would contribute to understanding long- and short-term in vivo decomposition of ET to ethylene. Chemical name used: (2-chloroethyl)phosphonic acid (ethephon).
Effect of Magnesium and Manganese Nutrition on Watermelon Growth and Manganese Toxicity
Authors: Elamin Osman M. , Wilcox Gerald E.
Published: August 2022

Watermelon [Citrullus lanatus (Thunb.) ‘Sugar Baby’ was grown in sand culture to evaluate Mn uptake as affected by solution concentration of Mn and Mg. Manganese toxicity symptoms were developed first on the lower mature leaves as small, distinct, blackish-brown speckling on the lower leaf surface that progressed to extensive vein browning and necrotic lesions. Leaves developed toxicity symptoms when they contained ≥1325 mg·liter−1 Mn. Growth was reduced at Mn concentrations in nutrient solution ≥22.5 mg·liter−1. Development of Mn toxicity symptoms was delayed with increasing Mg concentrations in solutions. Increasing Mg concentration in solution to 48 or 96 mg·liter-1 reduced Mn composition and Mg uptake per unit root surface at 2 and 30 mg·liter-1 Mn in solution, but had no effect at 60 mg·liter-1 Mn in solution.
Bermudagrass Germplasm Adaptation to Natural Pest Infestation and Suboptimal Nitrogen Fertilization
Authors: Busey Philip
Published: August 2022

Bermudagrass (Cynodon spp.) turf in subtropical Florida normally requires higher levels of N than other grasses and frequently requires pesticide applications. Three sequential 2-year cycles of clonal selection were performed in replicated field plots to recognize bermudagrass germplasm adapted to suboptimal fertilization and natural pest infestation. Low fertility, 19 to 25 g N·m−2, was applied yearly, including the establishment phase. No nematicides, fungicides, or insecticides were applied. Severely damaging mole cricket (Scapteriscus sp.) populations were left uncontrolled. Among 95 clones, 4 experimentals (FB-109, PI-291586, T-72-54, and FL-2400) survived repeated cycles with relatively high turfgrass coverage and quality. Among cultivars, only ‘Tifgreen-II’ and ‘Ormond’ performed well. African introductions and artificially-induced mutants of hybrid cultivars were the best sources of adapted germplasm. Although the mechanism of this adaptation is unknown, field tests were an effective prescreening method for clonal selection.
Effect of Light Intensity and Carbohydrate Reserves on Flowering in Olive
Authors: Stutte G.W. , Martin G.C.
Published: August 2022

In the article “Effect of Light Intensity and Carbohydrate Reserves on Flowering in Olive” by G.W. Stutte and G.C. Martin (J. Amer. Soc. Hort. Sci. 111:27–31, Jan. 1986), the following correction should be noted. On p. 28, under Materials and Methods, the sentence “The 80% methanol insoluble materials were suspended in saturated CaSO4 at pH 12.0 and boiled …” should read “The 80% methanol insoluble materials were suspended in saturated CaOH at pH 12.0 and boiled …”.
Improved Performance of Bearing ‘Delicious’ Apple Trees with Nitrogen and Phosphate Fertilization in a Low-phosphorus Soil
Authors: Raese J. Thomas
Published: August 2022

Bearing 15-year-old ‘Oregon Spur’, ‘Redspur’, and ‘Wellspur Delicious’/seedling apple (Malus domestica Borkh.) trees in a low-P (2 to 4 ppm) soil were treated over 3 years with different forms and rates of N and N + P fertilizers to overcome a severe condition pf low vigor and low yields. Fruit size and leaf N were greater on trees receiving all forms of N fertilizer than on the untreated controls. Levels of leaf P were up to 2 times greater on NH4H2P04 [mono-ammonium phosphate (MAP)] treated trees than on the controls or N-only [(NH4)2S04, NH4NO3, Ca(NO3)2 or urea] treated trees. In most instances, the higher rates of MAP (applied in 1983 and 1984) resulted in greater shoot extension and leaf weight than the controls and most of the N-only treated trees. Yield (3-year mean) was greater on ‘Oregon Spur’ and ‘Redspur’ cultivars treated with the moderate rate of MAP than in the controls or in most of the N-only treated trees.
Effect of Harvest Maturity on the Final Fruit Composition of Cherry and Large-fruited Tomato Cultivars
Authors: Picha David H.
Published: August 2022

Fruit of 2 cherry tomato (Lycopersicon esculentum var. cerasiforme Alef.) cultivars [‘Large Red Cherry’ (‘LRC’) and ‘Small Fry’ (‘SF’)] and 2 large-fruited tomato (Lycopersicon esculentum Mill.) cultivars (‘Duke’ and ‘Sunny’) were harvested green, ripened at 23°C, and analyzed for sugars and organic acids 6 days after breaker stage. Both fructose and glucose concentration decreased in ‘LRC’ and ‘SF’ fruit with less-mature harvested fruit. Maturity at harvest had no effect on the concentration of either sugar in ‘Duke’ or ‘Sunny’ fruit. ‘LRC’ had the highest fructose and glucose concentration among cultivars. Increased citric acid concentration was found with less-mature harvested fruit, except in ‘LRC’. Malic acid concentration within cultivars was similar in the fruit harvested more mature, but decreased with less-mature fruit in ‘Duke’ and ‘Sunny’. ‘LRC’ and ‘SF’ fruit had more citric and malic acid than ‘Duke’ or ‘Sunny’. Cherry tomato cultivars had a higher percentage of locular tissue than the large-fruited cultivars.
Effects of Fruit Maturity, Juice Storage, and Juice Extraction Temperature on Quality of ‘Concord’ Grape Juice
Authors: Morris J.R. , Sistrunk W.A. , Junek J. , Sims C.A.
Published: August 2022

A factorial study was designed to examine the effects of fruit maturities, juice extraction temperatures, storage time, and storage temperature on the quality of ‘Concord’ grape (Vitis labrusca L.) juice. Mature grapes produced juice with superior sensory quality and better objective color initially than less-mature grapes, but juice from grapes at both maturities had similar sensory quality after 18 months. The high extraction temperature (99°C) resulted in juice with better color initially than extraction at 60°, but juice extracted at 85° or 99° resulted in greater browning and loss of total anthocyanins during storage than extraction at 60°. High storage temperature (35°) greatly accelerated quality loss. Sensory color ratings correlated better with a ratio of absorbances at 520/430 nm (r = 0.95) and a/b (r = 0.92) than other objective color measurements.
Effects of Lime Type on Yields and Leaf Concentrations of Several Vegetable Crops as Related to Soil Test Levels
Authors: Smith C.B. , Demchak K.T. , Ferretti P.A.
Published: August 2022

The effects of liming with and without fertilizer on tomatoes (Lycopersicon esculentum Mill), sweet corn (Zea mays L.), snapbeans (Phaseolus vulgaris L.), and cabbage (Brassica oleracea L.) were evaluated in experiments in 11 production areas in 1981–83. Calcitic, calcitic with 3% Mg, and dolomitic lime types (fineness—95% through a 100-mesh sieve) at rates of 4.5–15.7 t·ha−1 were compared with unlimed checks. High lime rates increased yields and had no deleterious effects. Substantial changes in soil pH and Ca and Mg saturation took place within a year of application. Leaf Mn concentrations and to a lesser extent leaf Zn and B were decreased by liming. Calcitic lime increased leaf Ca but depressed leaf Mg, especially at rates of 13.4–15.7 t·ha−1. Comparable dolomitic lime treatments enhanced leaf Mg substantially but did not increase leaf Ca. Within 2 to 3 months of lime application, leaf analyses showed that the calcitic type usually supplied reasonable amounts of Ca, the dolomitic type consistently supplied substantial quantities of Mg, and both types reduced leaf Mn.
Effect of Fertilizer Applications, Plant Age, and Rainfall on the Yield and Fruit Size of Rabbiteye Blueberry Clone T-110
Authors: Austin Max E. , Bondari K.
Published: August 2022

A field planting on a Leefield loamy sand soil of clone T-110, a mature rabbiteye blueberry (Vaccinium ashei Reade.), was subjected to 6 types of fertilizer using various carriers of N and/or different supplements. The rates of fertilizer applied were 0 (no fertilizer), 1 (N at 67.25 kg·ha−1), and 2 (N at 134.5 kg·ha−1) over an 8-year period. Yield and fruit size were responsive to plant age, fertilizer rate, and the rate of annual precipitation. The 6 fertilizer formulations did not vary in their effects on blueberry yield or fruit size.