bluuebunny/crossref_metadata_2025 huggingface dataset:
Postharvest Preprocessing Temperature Effects on the Quality and Particle Size of Finished Applesauce
Authors: Massey L. M. , McLellan M. R.
Published: August 2022

Postharvest holding of apples (Malus domestica Borkh) for processing influenced the texture (“graininess”) of the finished sauce in a eultivar-specific but inconsistent manner. Following holding at 0°C and 18°, there was a positive correlation between firmness of ‘Cortland’ and ‘Rome Beauty’ apples and average particle size of the finished sauce in that the softest fruit produced the finest grained sauce. There also was a positive correlation between firmness of ‘Idared’ and sauce texture following holding at 18°, but a negative correlation following holding at 0°. ‘Rhode Island Greening’ fruit appeared to be intermediate in response, but this observation was complicated by the occurrence of low temperature internal breakdown. Uronide analyses on the largest and the smallest particle size fractions of finished sauce indicate that these variations among cultivars may be related in some manner to differences in pectin degradation. However, such differences do not explain the negative correlation between tissue firmness and particle size in ‘Idared’ fruit stored at 0°.
Effects of Vesicular-arbuscular Mycorrhizae and Nitrogen Source on Growth and Transport Amino Acid Composition of Pittosporum tobira
Authors: Coxwell Michael A. , Johnson Charles R.
Published: August 2022

Pittosporum tobira plants were inoculated with the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus mosseae or provided with an inoculum filtrate (nonVAM) and fertilized with 1 of 5 NH4+/NO3− ratios. Colonized plants had more branching, greater fresh weight, and higher visual grades than nonVAM plants, especially when grown at 50%–75% NO3−-N. Colonized plants also had higher concentrations of transport amino acids in xylem sap compared to nonVAM plants. Results suggest that colonization by Glomus mosseae may affect N metabolism in P. tobira.
Comparison of Three Methods for Determining the Floral or Vegetative Status of Strawberry Plants
Authors: Durner Edward F. , Poling E. Barclay
Published: August 2022

Three methods for determining the vegetative or floral status of the cultivated strawberry (Fragaria × ananassa Duch.) were compared. Dissection under a stereoscope was the most reliable method, followed by macroscopic evaluation of flower cluster development under long days. Macroscopic flower cluster production was highly dependent on the amount of natural chilling received by the plants prior to being placed under long day conditions, and differed among cultivars. Central longitudinal microtomed sections of apical meristems were unreliable due to their subjective nature. The time of flower bud initiation also was estimated. ‘Allstar’, ‘Earliglow’, and ‘Tribute’ initiated flower buds in late September; ‘Apollo’ and ‘Sequoia’ in early October; and ‘Titan’ in mid-October.
Effects of Timing and Rate of Glyphosate Application on Toxicity to Selected Woody Ornamentals
Authors: Neal J. C. , Skroch W. A.
Published: August 2022

Thirteen species of woody ornamentals were treated over-the-top with glyphosate in a 6 × 6, rate by time factorial experiment. The influence of application timing on glyphosate phytotoxicity was significant for all species. The times of maximum tolerance and injury were species dependent. Species were organized into 4 response groups based on the effects of application time. Group 1 species, including ajuga (Ajuga reptans L.), azalea (Rhododendron obtusum Planch. ‘Coral Bells’), and a variegated liriope (Liriope muscari L.H. Bailey), were injured on all application dates. Species in groups 2, 3, and 4 exhibited tolerance to fall applications of glyphosate. Group 2, including wax leaf privet (Ligustrum japonicum Thunb.), sustained maximal injury from spring applications. Group 3 species, including Compacta holly (Ilex crenata Thunb. ‘Compacta’), were injured most by summer applications of glyphosate. However, Blue Rug juniper (Juniperus horizontalis Moench ‘Wiltonii’), a representative of group 4, was tolerant of glyphosate applications, sustaining only temporary tip chlorosis from spring and early summer treatments. First season evaluations were not sufficient to describe the ultimate effects of glyphosate on plant quality. Visual and objective evaluations in the 2nd growth season also were necessary. Chemical name used: N-(phosphonomethyl) glycine (glyphosate).
Effects of Sulfur Dioxide and Ambient Ozone on Concord Grapevine Growth and Productivity
Authors: Musselman R. C. , Forsline P. L. , Kender W. J.
Published: August 2022

Three separate experiments were conducted in a mature Vitis labruscana Bailey ‘Concord’ vineyard in New York to determine the response of grapevines to daily, season-long sulfur dioxide (SO2) exposure, or to intermittent SO2 exposure simulating emissions from a 1700 MW coal-fired power plant. There was little SO2-induced necrosis on grape foliage from daily or power plant SO2. However, both treatments in ambient air increased susceptibility of leaves to oxidant stipple injury due to ambient ozone (O3). Daily SO2 increased leaf chlorosis. Power plant SO2 had no effect on vine growth, yield, or shoot maturation. Daily SO2 reduced soluble solids, growth, yield, and shoot maturation of grapevines. Damage to grapevines from SO2 seemed to be independent of SO2 induced leaf necrosis. SO2 reduced foliage tolerance to O3 injury in grapevines already stressed by ambient O3.
Response of Cabbage to Insecticide Schedule, Plant Spacing, and Fertilizer Rates
Authors: Csizinszky A. A. , Schuster D. J.
Published: August 2022

Cabbage (Brassica oleracea L. Capitata Group ‘Market Prize’) was grown in the spring (February to April) 1981 and fall-winter (October to January) 1981–82 with 2 insecticidal spray schedules conducted weekly and on demand; 2 in-row spacings, 23 and 38 cm; and 2 fertilizer rates, low (152N–53P–139K and 8 Mg kg/ha), and high (257N–99P–261K and 15 Mg kg/ha). Fenvalerate [Cyano (3-phenoxyphenyl) methyl-4-chloro-alpha-(1-methylethyl) benzeneacetate] at 0.112 kg a.i./ha was applied either weekly or when a threshold of 0.5 lepidopterous larval feeding injuries/plant was equalled or exceeded. With the weekly insecticide treatment, 12 and 10 sprays were applied, respectively, in the spring and fall, vs. 1 and 2 applications, respectively, for the 2 seasons in the demand plots. Insect damage ratings were lower in the weekly sprayed than in the demand plots; however, marketable yields (kg/ha) and average head size were not affected by spray schedules. In both seasons, marketable yields were greater at the 28 cm spacing than at 38 cm, whereas average head sizes were greater at 38 cm than at 23 cm. The high fertilizer rate increased head size in both seasons, but increased marketable yields only in the spring.
Relationship between GA Application and Phyllomorph Length in Streptocarpus
Authors: Lyons R. E. , Veilleux R. E. , Booze-Daniels J. N.
Published: August 2022

In the article “Relationship between GA Application and Phyllomorph Length in Streptocarpus” by R.E. Lyons, R.E. Veilleux, and J.N. Booze-Daniels [Journal 10(5):647–650, 1985] the figure captions were reversed. The correct figures and captions appear below.
Roles of Four Sorbitol Related Enzymes and Invertase in the Seasonal Alteration of Sugar Metabolism in Apple Tissue
Authors: Yamaki Shohei , Ishikawa Kazuko
Published: August 2022

Activities and roles of 4 sorbitol enzymes, sorbitol-6-P dehydrogenase, NAD+-dependent sorbitol dehydrogenase, NADP+-dependent sorbitol dehydrogenase and sorbitol oxidase, and acid invertase in apple (Malus domestica Borkh. ‘Jonnagold’) leaves and fruit were studied. Almost all of the soluble carbohydrates in leaves are present as sorbitol throughout the season. Sorbitol-6-P dehydrogenase had the highest activity among the enzymes, being high in young leaves and decreasing with age; whereas NAD+- and NADP+-dependent sorbitol dehydrogenases and sorbitol oxidase activities were barely detectable. Sorbitol was translocated from leaves to fruits where it was readily metabolized to other sugars, so the sorbitol concentration did not increase. NAD+-dependent sorbitol dehydrogenase that converts sorbitol to fructose had the highest activity of the 4 enzymes in developing fruits. Its activity rose in June, decreased in midseason, and increased again with fruit maturation. The fluctuation in enzyme activity corresponded to changes in fructose concentration. Sorbitol oxidase activity, which was about one-fifth that of NAD+-dependent sorbitol dehydrogenase, increased proportionately as fruits enlarged. Acid invertase activity was distinctly higher than sorbitol enzyme activities in both leaves and fruit, but its roles in sugar translocation and metabolism were not clearly established. The levels of sorbitol in stems and peduncles remained relatively constant during the season indicating that little metabolism occurred in the phloem during transit.
Response of Potatoes to Nitrogen Form and to Change in Nitrogen Form at Tuber Initiation
Authors: Davis Jeanine M. , Loescher Wayne H. , Hammond Max W. , Thornton Robert E.
Published: August 2022

A controlled environment study was conducted to determine if ‘Russet Burbank’ potatoes (Solanum tuberosum L.) were more tolerant of NH4-N as established plants than as young plants. When grown on one N source for 86 days, root and shoot growth were best with NO3-N, intermediate with NH4 + NO3, and least with NH4-N. Changing the N source from NO3-N or NH4 + NO3 to NH4-N at tuber initiation (58 days after planting) reduced both shoot and root growth. Conversely, changing the N source from NH4-N to NH4 + NO3 improved growth. The highest tuber weights were obtained with continuous NH4 + NO3 or when NH4-N was applied at tuber initiation to plants previously grown on NO3-N alone. Nitrogen source also influenced absorption of other nutrients. Changing the N source once plants were established, however, did not have a consistent effect on mineral composition. We conclude that when NH4-N is the sole form of N available to the plant, it is detrimental to potato growth regardless of stage of development.
Carbon Balance Model of a Growing Apple Shoot: I. Development of the Model
Authors: Johnson R.S. , Lakso A.N.
Published: August 2022

A computer model simulating the C balance of a growing ‘Jonamac’ apple (Malus domestica Borkh.) shoot was constructed to estimate the time of first net carbohydrate export from the shoot. The model was based on measurements of net photosynthesis and dark respiration rates and estimates of the dry weight in the different components of the shoot. Under the prevailing weather of 1981, the model indicates that a shoot growing to a final length of 50 cm became a net exporter of carbohydrates 19 days after budbreak, a time corresponding to a shoot 4 cm long with 10 unfolded leaves. Assuming the same early growth rates, a shoot with a final length of 2 cm starts exporting at 15 days after budbreak. The total export of carbohydrates remains higher from short shoots than long shoots until 36 days after budbreak, indicating that short shoots supply greater amounts of carbohydrates to the rest of the plant during this early period. The model estimates the total import of carbohydrates from reserves of about 165 mg for the long shoot and 80 mg for the short shoot. In each instance, these reserves only accounted for about 20% of the total carbohydrates used by the shoot up to that point. The remainder was supplied by current photosynthates.
Root Cell Membrane Heat Tolerance of Two Dwarf Hollies
Authors: Ingram Dewayne L.
Published: August 2022

The thermostability of Ilex crenata Thunb. ‘Helleri’ and Ilex vomitoria Ait. ‘Schellings’ root cell membranes at supraoptimal temperatures were determined using electrolyte leakage procedures with excised roots. Mathematical models were developed to describe effects of treatment temperature and exposure time interactions on membrane thermostability. Critical temperature, Tc, decreased linearly as exposure duration increased exponentially, and predicted Tc for ‘Helleri’ and ‘Schellings’ were 51.0 ± 0.8 and 52.6 ± 0.7°C, respectively, for a 30-min exposure and 43.9 ± 0.8 and 46.7 ± 0.3° for a 300-min exposure. Three dimensional plots of the fitted mathematical functions are presented.
Response of Citrus Seedlings to Various Field Inoculation Methods with Glomus deserticola in Fumigated Nursery Soils
Authors: Ferguson J.J. , Menge J.A.
Published: August 2022

Broadcasting, banding, and drilling were more effective in the field inoculation of plants with the vesicular arbuscular mycorrhizal fungus, Glomus deserticola Trappe, Bloss and Menge than seed inoculation or the application of lyophilized roots to both direct-seeded and transplanted citrus seedlings. Mechanized field inoculation of direct seeded and transplanted citrus seedlings is feasible, using fertilizer banding equipment, and seeding machines. In oculum remained consistently infective after soil inoculation for up to 2.5 months in fumigated field soil and for up to 1.5 months in mycorrhizal pot cultures of citrus grown in the greenhouse.
Resistance of Sweet Corn to Damage by Blackbirds and Starlings
Authors: Dolbeer R.A. , Woronecki P.P. , Stehn R.A.
Published: August 2022

Twenty-five cultivars of sweet corn were evaluated for resistance to bird damage in an aviary during 1983 and 1984. A free-choice test was used in which red-winged blackbirds (Agelaius phoeniceus L.), common grackles (Quiscalus quiscula L.), and starlings (Sturnus vulgaris L.) could select from among 8 cultivars at a time. In addition, no-choice conditions in which red-wings were presented with only one cultivar at a time were tested. In the free choice test, there were significant differences among bird species and corn cultivars in the amount of damage. The most damaged cultivar had 4.8 times the damage of the least damaged cultivar. Starlings did the most damage and grackles the least, but all bird species damaged the cultivars in the same approximate order. Differences in damage among cultivars were diminished in the no-choice tests; however, the damage ranking of cultivars was similar to that of the free-choice test. Husk weight, length of husk beyond kernels, and weight of husk extension were the best correlates (all negative) with damage. The incorporation of these characteristics into sweet corn lines should increase cultivar resistance to damage by birds.
Constriction and Decline of ‘Stanley’ Prune Associated with Tomato Ringspot Virus
Authors: Cummins James N. , Gonsalve Dennis
Published: August 2022

Tomato ringspot virus (TmRSV) was consistently detected in myrobalan (Prunus cerasifera) and in 8 other plum rootstocks that exhibited prune brownline (PBL) symptoms at the graft unions. The infected rootstocks included Prunus domestica cvs. St. Julien A, Brompton, Ackermanpflaume, and Pershore and 6 seedling lines of P. cerasifera. Own-rooted ‘Stanley’ prune trees remained free of natural infection by TmRSV for 14 years on a site where 36% of the ‘Stanley’ trees on other rootstocks became infected. Mortality among TmRSV-infected trees on myrobalan stocks was higher than among infected trees on P. domestica roots. Own-rooted ‘Stanley’ trees are suggested for extensive commercial trial in areas infected with TmRSV.
Effect of Different Artificial Shading Times and Natural Light Intensities on the Fruit Quality of ‘Bing’ Sweet Cherry
Authors: Patten K.D. , Proebsting E.L.
Published: August 2022

Limbs of ‘Bing’ cherries (Prunus avium L.) were shaded with neutral density shade structures to reduce light levels to 10–15% full sun. Three placement times were used: a) petal fall to pit hardening (PF-PH), b) pit hardening to harvest (PH-H), and c) petal fall to harvest (PF-H). Shaded limbs had reduced fruit set, and fruit color and soluble solids were less in comparison to fruit from unshaded limbs. Fruit from shaded limbs were smaller than unshaded for the first 2 harvests, but for the last 2 harvest dates, fruit shaded from PF-PH or PF-H were larger. The time to reach dark red maturity was delayed 5 days by shading from PF-PH or PH-H and 12 days by shading from PF-H. When compared at equal color maturities, fruit from unshaded limbs were firmer than those from shaded limbs. In a study using natural shade, the relationship of fruit color and soluble solids to the percentage of full sun (FS) was logarithmic, with both variables dramatically reduced at light levels below 10–15% FS. Neither fruit weight nor firmness were related to the percentage of FS.
Effect of Excess Boron on Broccoli, Cauliflower, and Radish
Authors: Francois L.E.
Published: August 2022

The boron tolerance of broccoli (Brassica oleracea L. Italica Group), cauliflower (Brassica oleracea L. Botrytis Group), and radish (Raphanus sativus L.) was determined in large, outdoor sand cultures. Boron treatments were imposed by irrigation with culture solutions that contained 1.0, 4.0, 8.0, 12.0, 16.0, or 20.0 mg B·liter−1 for broccoli and cauliflower, and 1.0, 3.0, 6.0, 10.0, 13.0, or 16.0 mg B·liter−1 for radish. Relative yield was reduced 1.8%, 1.9%, and 1.4% with each unit (mg·liter−1) increase in soil solution B (Bsw) above 1.0, 4.0, and 1.0 mg B·liter−1 for broccoli, cauliflower, and radish, respectively. Increasing Bsw significantly reduced plant size of all 3 vegetables. Over the B range tested, no leaf injury was apparent for these 3 vegetables.
Factors Affecting the Anthocyanin Content of Cranberry
Authors: Sapers Gerald M. , Graff Gavin R. , Phillips John G. , Deubert Karl H.
Published: August 2022

Samples of 16 cranberry (Vaccinium macrocarpon Ait.) clones, sorted into subsamples on the basis of berry size and coloration, were analyzed for juice content, soluble solids, titratable acidity, and anthocyanin content. The soluble solids : acidity ratio was greater for more highly colored subsamples but did not vary with berry size. The anthocyanin content of subsamples of different berry size varied in proportion to the surface to volume ratio. Anthocyanin recovery in expressed juice was independent of berry coloration and size. Variability in anthocyanin content within samples reflected differences in environmental factors, such as light exposure, superimposed on ripeness differences. Variability in sample anthocyanin content depended more on berry size differences than on differences in surface coloration.
Characterization of Peach Roots in Fox Sand as Influenced by Sprinkler Irrigation and Tree Density
Authors: Layne R.E.C. , Tan C.S. , Perry R.L.
Published: August 2022

The trench profile method was used to map peach [Prunus persica (L.) Batsch cv. Harken/Siberian C] roots in an 11-year-old experimental orchard with 3 levels of irrigation and 3 tree densities. Roots near the drip line, 150 cm from the trunk, were mapped to a depth of 120 cm, while those 30 cm from the trunk were mapped to a depth of 240 cm. Location, number, and diameter of roots near the drip line were greatly affected by irrigation and only moderately affected by tree density. The total number, and number of small-diameter (<2 mm) roots were highest in nonirrigated plots and decreased with increasing levels of irrigation. A similar but much reduced pattern was evident for medium- (2 to 5 mm) and large- (>5 mm) diameter roots. Irrigation promoted shallow rooting near the drip line. Trees receiving the low and high level of irrigation had 35% and 42%, respectively, of their roots in the top 30 cm of soil, compared with only 18% for those in nonirrigated plots. At depths of 30 to 120 cm in nonirrigated plots, 82% of the roots near the drip line were found in these soil layers, compared with 65% for the low and 58% for the high level of irrigation. Tree density had no effect on total root number near the drip line, although there was an increase in root number with an increase in tree density 90 to 120 cm from the trunk on both sides of the tree, and a decrease in root number with an increase in tree density within 60 cm of the trunk. Rooting occurred readily in the Ap, Bm, and Bt soil horizons, but very little rooting occurred in the gray sand comprising the Ck horizon, which had a high pH (7.8) and poor soil water retention characteristics.
Field Performance and Clonal Variability in Sweet Potatoes Propagated in Vitro
Authors: Templeton-Somers Karen M. , Collins Wanda W.
Published: August 2022

Six methods of propagating sweet potato (Ipomoea batatas L.), including 3 in vitro propagation methods, nodal propagation, and propagation by slips and cuttings from bedded roots of ‘Jewel’, were evaluated for field performance of the resulting plants and for the degree of plant-to-plant variability. The 2-year experiment (1982 and 1983) included a carryover study with plants obtained from the bedded roots of the first year's study. Plants were evaluated individually for yield, skin and flesh color, mutation frequency, dry matter, and protein content. In both years, plants propagated by stem cuttings and by slips from bedded roots produced higher yields than those propagated by tissue culture methods. Plants propagated by regeneration from cultured leaf explants were consistently lower in yield than plants obtained by all other methods. In the 1983 study, plants from stem cuttings from field-bedded roots significantly out-yielded plants from all other treatments. Stem cuttings from roots bedded in pots in a growth chamber out-yielded all tissue culture propagation methods, even though the tissue-culture explants also were obtained from these same roots. The carryover study showed that all differences in yield due to propagation method were dissipated with a single cycle of the normal propagation method for sweet potato. When yield data were analyzed according to the mother root origin of the plant material, there were significant differences among plants originating from different roots. Differences in skin color mutation frequencies due to propagation method existed in the 1982 study; however, the 1983 study demonstrated that these differences were also due to the origin of the plant material.
The Influence of Nitrification on the Medium Solution and Growth of Holly, Azalea, and Juniper in a Pine Bark Medium
Authors: Niemiera Alexander X. , Wright Robert D.
Published: August 2022

Three genera of woody plants were container-grown in a pine bark medium. Pine bark was amended or unamended with nitrapyrin (NI) and fertilized with an NH4-N fertilizer. Medium solution NH4-N concentrations of bark without NI decreased rapidly for the first 3 to 5 weeks with a concomitant increase in NO3-N concentrations. Medium solution pH at 0 NI decreased 0.8 unit during periods of rapid NO3-N accumulation. The low medium solution pH of the 0 NI treatment resulted in solution Ca, Mg, and Mn concentrations that were several times greater than at 82 μg of NI. Correspondingly, tissue concentrations of these ions were generally greater at the 0 NI treatment than at the 82 μg NI treatment. In general, there were no differences in shoot dry weight in response to NI treatment. Results indicate that nitrification is important in the nutrition of container-grown plants.
Responses of Daminozide-treated ‘Delicious’ and ‘Idared’ Apples to Simulated Low-ethylene CA Storage
Authors: Liu F.W.
Published: August 2022

Daminozide-treated and non treated ‘Delicious’ and ‘Idared’ apples (Malus domestica Borkh.) were stored for 7 to 7.5 months in simulated low-ethylene (<1 μl·liter−1) or normal-ethylene (500 μl·liter1) controlled-atmosphere (CA) storage. The simulated CA storage was a flow-through CA storage in 19-liter jars at 0°C. The storage atmosphere contained 2.5-3% O2, 3% CO2, 94-94.5% N2, and nearly 100% RH. Nontreated ‘Delicious’ and ‘Idared’ apples did not respond to low-ethylene CA, except that low-ethylene CA reduced the incidence of storage scaled on ‘Delicious’ apples. Daminozide-treated ‘Delicious’ apples did not respond to low-ethylene CA; the apples being firm after both low-ethylene and normal-ethylene CA storage. The response to low-ethylene CA by daminozide-treated ‘Idared’ apples was a reduced rate of softening of the apples after storage. The daminozide treatment significantly suppressed the ethylene production of both cultivars of apples in simulated low-ethylene CA storage. Chemical names used: butanedioic acid mono(2,2-dimethylhydrazide)(daminozide).
Effects of Fruit Detachment on Ethylene Biosynthesis and Loss of Flesh Firmness, Skin Color, and Starch in Ripening ‘Golden Delicious’ Apples
Authors: Lau O.L. , Liu Y. , Yang S.F.
Published: August 2022

Prior to 25 Oct., about 4-6 weeks (1983) or 3-5 weeks (1984) after the normal commercial harvest period, 1-aminocyclopropane-l-carboxylic acid (ACC), ethylene-forming enzyme (EFE), and internal ethylene concentration (IEC) in ‘Golden Delicious’ (Malus domestica Borkh.) apples attached to the tree were low. Thereafter, they began to increase rapidly. The increase in both ACC and IEC was earlier in detached preclimacteric fruit than in fruit attached to the tree. The increase of EFE coincided with that of IEC in detached fruit kept at 20°C. Attached fruit subsequently attained a higher level of ACC but a lower level of IEC as compared to the detached fruit. The results suggest that inhibitor(s) supplied from the tree not only delayed the accumulation of ACC in the fruit but also greatly inhibited its subsequent conversion to ethylene. Once the ripening process is initiated, the development of EFE precedes the development of ACC synthesis in both attached and detached fruit. Since attached fruit showed a steady loss of flesh firmness, green skin color, and starch, these changes did not appear to be related directly to the levels of ACC and internal ethylene. Detached fruit stored at 0° accumulated ACC and increased IEC slightly earlier than those stored at 20°. The magnitudes of these increases during subsequent storage at 0° were, however, smaller than those at 20°.
Manganese Toxicity in Watermelon Plants as Influenced by Nitrogen Form
Authors: Elamin Osman M. , Wilcox Gerald E.
Published: August 2022

Watermelon [Citrullus lanatus (Thunb.)] ‘Sugar Baby’ seedlings were grown in sand culture leached with nutrient solution containing 2, 25, or 50 mg·liter−1 Mn in combination with NH4 or NO3-N to evaluate the effects of N form on growth, composition, and development of Mn toxicity. Nitrogen form treatments consisted of continuous NO3, continuous NH4, and a treatment in which NH4 was replaced by NO3 after Mn toxicity symptoms were first observed on NO3-treated plants. Watermelon plants produced the most growth at all Mn levels with N supplied as NO3, least with NH4, and intermediate with the NH4-to-NO3 shift treatment. Plants grown with NO3-N at 25 and 50 mg·liter−1 Mn had reduced growth and developed Mn toxicity symptoms with Mn concentrations >1700 μg·g−1 in shoot tissues. However, with NH4 the Mn treatments had no effect on growth, no Mn toxicity symptoms developed, and Mn concentrations in shoot tissue were <800 μg·g−1. Shifting plants from NH4-to-NO3 nutrition at 50 mg·liter−1 Mn in solution stimulated rapid Mn absorption and produced Mn toxicity symptoms within 3 days.
The Mechanism of Regulation of ‘Bartlett’ Pear Fruit and Vegetative Growth by Irrigation Withholding and Regulated Deficit Irrigation
Authors: Chalmers D.J. , Burge G. , Jerie P.H. , Mitchell P.D.
Published: August 2022

After initially withholding irrigation (WI) to dry out the root zone of pear trees, regulated deficit irrigation (RDI) applied to replace 23% and 46% of evaporation over the planting square (Eps) was compared with 69% and 92% Eps applied during the WI and RDI periods, respectively (full irrigation). Irrigation was increased to 120% Eps on all treatments after rapid fruit growth commenced. Leaf water potential (ψ1) measured at dawn and midday became less negative during RDI than during WI but in both periods was more negative than the control (69%/92% Eps). On the other hand, ψ1 of treatments receiving WI and RDI became less negative than the control when all irrigation treatments were increased to 120% Eps. Withholding irrigation followed by RDI reduced vegetative growth by 52%. In contrast, however, WI did not inhibit fruit growth, while, during RDI following WI fruit, growth was stimulated. A similar but greater stimulation of fruit growth (consistent with relatively less negative ψ1) was measured on WI/RDI plants when all treatments received 120% Eps. This stimulation of fruit growth increased yields by about 20%. The results indicate fruit osmoregulate to maintain and/or increase growth at the expense of inhibited vegetative growth when WI and or RDI reduce ψ1 in spring to values approaching −0.5 MPa at dawn.
Dry Matter Distribution and Responses to Pruning Within a Population of Standard, Semidwarf, Compact, and Dwarf Peach Seedlings
Authors: Scorza Ralph , Zailong Li , Lightner G.W. , Gilreath Lenard E.
Published: August 2022

In the article “Dry Matter Distribution and Responses to Pruning Within a Population of Standard, Semidwarf, Compact, and Dwarf Peach Seedlings”, by Ralph Scorza, Li Zailong, G.W. Lightner, and Lenard E. Gilreath (J. Amer. Soc. Hort. Sci. 111:541–545, July 1986), Table 2, under the “Variable” column, which reads “Avg length of shoots (cm)”, should read “Avg length of shoots (mm)”.
Auxin Movement in Strawberry Fruit Corresponds to Its Growth-promoting Activity
Authors: Southwick Stephen M. , Poovaiah B.W.
Published: August 2022

NAA at 10–3 m concentration plus 2% dimethylsulfoxide (DMSO) in lanolin paste, applied to apices of unpollinated strawberry (Fragaria × ananassa Duch. ‘Ozark Beauty’) flower receptacles, promoted growth and receptacle elongation resulting in full-sized fruit. Movement of [14C]NAA occurred predominantly in a basipetal direction from the treated apex to the receptacle base. Growth occurred only at the site of application when NAA was applied to the receptacle base or longitudinal half. Acropetal or lateral movement of [14C]NAA in receptacles was minimal. Movement of [14C]NAA out of receptacles and into pedicels was basipetal in nature and was slower than that noted within the receptacles. These data demonstrate that polar auxin movement in strawberry receptacles appears to promote uniform growth at some distance from the point of application. Chemical names used: 1-naphthaleneacetic acid (NAA); indole-3-acetic acid (IAA); and 2,3,5-triiodobenzoic acid (TIBA).
Control of Soil Insect Injury by Resistance in Sweet Potato
Authors: Jones Alfred , Schalk J.M. , Dukes P.D.
Published: August 2022

Soil insect root injury to resistant sweet potato [Ipomoea batatas (L.) Lam.] cultivars ‘Regal’ and ‘Southern Delite’ was compared to injury to ‘Jewel’ and ‘Centennial’ in trials with the resistant-standard W-13 and the susceptible-standard SC 1149-19. Injury by three groups of insects was evaluated: the wirewoom-Diabrotica-Systena complex (WDS), which includes the southern potato wireworm (Conoderus falli Lane), the tobacco wireworm (C. vespertinus Fabricius), the banded cucumber beetle (Diabrotica balteata LeConte), the spotted cucumber beetle (D. undecimpunctata howardi Barber), the elongate flea beetle (Systena elongata Fabricius), the pale-striped flea beetle (S. blanda Melsheimer), and S. frontalis Fabricius (a flea beetle); the sweet potato flea beetle (Chaetocnema confinis Crotch.); and a white grub (Plectris aliena Chapin). Relative control estimates were obtained by comparison to the susceptible standard. ‘Regal’ and ‘Southern Delite’ provided good control of all three insect groups with control of all insect injuries of 79.2% and 81.0%, respectively. ‘Jewel’ and ‘Centennial’ were resistant to the sweet potato flea beetle and sustained less damage by WDS than the susceptible standard, but would still be classed as susceptible to WDS. ‘Centennial’ was as susceptible to the white grub as SC 1149-19. The levels of resistance demonstrated for ‘Regal’ and ‘Southern Delite’ would provide growers an alternative to insecticides for the control of these insects.
Growth and Fruiting of Apple and Cherry Trees as Affected by Trunk Looping
Authors: Byers R.E. , Carbaugh D.H.
Published: August 2022

Trunk looping of several apple cultivars on seedling roots reduced terminal shoot growth and trunk enlargement below the loop and increased root suckers. Growth was reduced most in the early years of tree growth. In the 5th, 6th, and 7th growing seasons, annual trunk enlargement was not affected, but growth suppression in the 2nd, 3rd, and 4th years reduced final trunk diameter measurements after seven seasons. Similarly, terminal shoot length was suppressed greatest in the early years and to a lesser extent in the 5th through the 7th growing seasons. Fruit number was unaffected by looping in the 5th growing season, but looping increased fruit number and fruit/cm2 trunk cross-sectional area in the 6th and 7th seasons in ‘Golden Delicious’, ‘Starkrimson Delicious’, and ‘Northwest Greening’, but not ‘Stayman’.
Changes in Water Potential and Dermal Extensibility During Grape Berry Development
Authors: Matthews M. A. , Cheng G. , Weinbaum S. A.
Published: August 2022

A comprehensive analysis of fruit water relations and the extensibility of the dermal tissue (skin) of Vitis vinifera cv. Cardinal berries was conducted throughout the period of biphasic growth. The pattern of berry growth was not coordinated with the patterns of berry water potential or turgor. It was anticipated, therefore, that cell wall extensibility and yield threshold varied during berry development. Measurements of uniaxial extensibility of dermal strips removed from berries indicated that total and plastic extensibility were relatively constant during stages I and II of berry growth, but increased significantly in the transition from stage II to stage III. The functional interrelationships between sugar accumulation, skin extensibility, and berry growth, which increases at the onset of stage III, remain to be elucidated.
The Role of Ethylene in Initiating Gum Duct Formation in Almond Fruit
Authors: Morrison Janice C. , Labavitch John M. , Greve L. Carl
Published: August 2022

Intact almond fruits [Prunus dulcis (Mill.) D.A. Webb.] showed a transient increase in ethylene production at the time of gum duct initiation. Treatment with ethylene promoted gum duct formation if applied 1 week before natural duct initiation, but had no effect when applied earlier. Silver thiosulfate, applied either as a spray or through bark-feeding, was found to delay natural duct initiation. AO A also delayed duct initiation when applied through bark-feeding, but not when applied as a spray. Chemical name used: aminooxyacetic acid (AOA).
Urea Hydrolysis in Potting Media
Authors: Elliott George C.
Published: August 2022

In the article “Urea Hydrolysis in Potting Media”, by George C. Elliott (J. Amer. Soc. Hort. Sci. 111:862–866, November, 1986), Figs. 2 and 3 were reversed. The correct figures and legends are printed below.
Floral Development, Flowering Patterns, and Growth Rate of Monoecious and Gynoecious Buffalo Gourd
Authors: Scheerens J.C. , Yousef Y.M.R. , Ralowicz A.E. , Gathman A.C. , Scheerens H.M.
Published: August 2022

The effect of sex expression on floral development, floral distribution, plant form, and growth rate was observed in monoecious and gynoecious buffalo gourd (Cucurbita foetidissima HBK.). Monoecious plants exhibited vegetative, male floral, mixed floral, and secondary vegetative phases in progression. During potentially male and potentially mixed floral phases of gynoecious plants, staminate flowers developed normally until male buds reached 2 to 3 mm in length. Thereafter, stamens degenerated and the resulting stamenless buds aborted. Gynoecious phenotypes produced pistillate flowers at earlier nodes than did their monoecious counterparts and, on individuals selected for detailed study, gynoecious plants produced about four times as many pistillate flowers as did monoecious plants. However, sex expression did not affect female bud ontogeny. On monoecious individuals, pistillate buds reached an thesis in about half as many days as was required for development of staminate buds. Growth rates and the patterns of growth were similar in monecious and gynoecious plants.
Changes in Apple Leaf Water Status and Vegetative Growth as Influenced by Crop Load
Authors: Erf Jeff A. , Proctor J.T.A.
Published: August 2022

Eleven-year-old ‘Golden Delicious’/M. 26 apple (Malus domestica Borkh.) trees were left unthinned (483 fruit/tree), thinned to one fruit/spur (370 fruit/tree), or completely defruited. Leaf water potential, leaf stomatal conductance, and leaf water content were monitored during the growing season. From 3 weeks after thinning and continuing to harvest, trees with an average of 483 or 370 fruit had significantly lower leaf water potentials than defruited trees. Trees thinned to 370 fruit had consistently higher leaf water potentials than unthinned trees with 483 fruit. Leaves on unthinned or one fruit/spur trees had higher stomatal conductances than leaves on completely defruited trees, although these differences were detected later in the season than those for leaf water potentials. No treatment differences in leaf water content were observed. Defruited trees had higher specific leaf weights, longer shoot extension, and greater increases in trunk cross-sectional area than those not defruited. Fruit size was greatest on trees thinned to one fruit/spur.
Isozyme Variation Among California Almond Cultivars: II. Cultivar Characterization and Origins
Authors: Hauagge R. , Kester D.E. , Arulsekar S. , Parfitt D.E. , Liu L.
Published: August 2022

Horizontal starch gel electrophoresis was used to study the variation of aspartate aminotransferase (AAT-1), glucose phosphate isomerase (GPI-2), leucine aminopeptidase (LAP-1) and phosphoglucomutase (PGM-1 and PGM-2) isozymes in 76 cultivars and accessions of almond. Cultivars could be separated into 40 classes for identification. Relationships among cultivars, based on historical records and isozyme similarities, show an original pool of seedling selections made before 1900. Most later-introduced cultivars are offspring or descendents of ‘Nonpareil’ and ‘Mission’ (‘Texas Prolific’), the other dominant parent.
Correlative Inhibition of Axillary Buds in Apple Nursery Trees in Relation to Node Position, Defoliation, and Promalin Application
Authors: Theron K.I. , Jacobs G. , Strydom D.K.
Published: August 2022

Sprouting of axillary shoots was studied in nursery apple trees (Malus domestica Borkh) following defoliation and Promalin application. Both Promalin and defoliation stimulated lateral bud outgrowth. Promalin was more effective when applied to buds without the inhibition imposed by the subtending leaf. In the absence of the subtending leaves there was a decreased tendency for buds to sprout at lower node positions. Buds most responsive to Promalin were between those subtended by small, partially expanded leaves and those subtended by fully grown leaves.
Root Hypoxia and Storage Breakdown of ‘Jonathan’ Apples
Authors: Gur Arye , Meir Shimon
Published: August 2022

Stored ‘Jonathan’ apple (Malus domestica Borkh) fruit from poorly aerated trickle-irrigated plots had a high incidence of “Jonathan breakdown” (starting as flesh browning beneath the peel) and, from sprinkle-irrigated plots, “Senescent breakdown” (starting from the core area). The flesh of such fruit was high in ethanol at picking time and in acetaldehyde after several months of storage. High ethanol levels in the fruit after 4 months of storage were related to a high ethylene production of the fruit. High soluble solid levels were characteristic of fruit prone to Jonathan breakdown but not to senescent breakdown. The acid content of the fruit flesh was directly correlated with the acetaldehyde content after several months of storage. The acetaldehyde content of the flesh of fruit from plots suffering from root hypoxia rose after 3 months of storage at 1°C. In contrast, the ethanol content of healthy fruit decreased gradually during storage. Fruit from plots suffering from root hypoxia, and particularly their peel, were low in Ca, Β, and Fe, but high in K. Low fruit Ca was related to high acid, acetaldehyde, and sorbitol levels. Fruit low in Ca softened rapidly in storage.
Genetics and Linkage Analysis of 19 Isozyme Loci in Apple
Authors: Weeden N.F. , Lamb R.C.
Published: August 2022

The polymorphism in nine enzyme systems in apple (Malus domestica Borkh.) was analyzed using horizontal starch gel electrophoresis. The systems studied included aspartate aminotransferase, diaphorase, glucosephosphate isomerase, isocitrate dehydrogenase, phosphoglucomutase, and triosephosphate isomerase. The products of at least 27 loci could be distinguished in these systems, 19 of which displayed polymorphism. Joint segregation analysis in populations derived from crosses between highly heterozygous cultivars revealed four multilocus linkage groups: Aat-c–Idh-1, Dia-2–Mdh-4, Gpi-c2-Aat–p, and (Dia-5, Pgm-p1)–(Mdh-2, Tpi-c2). Although several of the populations investigated had been prescreened for resistance to apple scab, cedar-apple rust, or fire blight, no correlation could be established between the inheritance of an allozyme and a resistant phenotype. The high frequency of duplicate loci encountered is in accordance with the postulated tetraploid nature of the genome.
Isozyme Banding Patterns and Their Usefulness as Genetic Markers in Peach
Authors: Durham R.E. , Moore G.A. , Sherman W.B.
Published: August 2022

The usefulness of isozyme banding patterns as genetic markers in peach [Prunus persica L. (Batsch)] was investigated using starch gel electrophoresis. Samples for electrophoresis included leaves of both juvenile and mature plants. A survey of 38 enzyme activity stains and five electrophoretic buffer systems was conducted. Only 12 staining systems produced well-resolved banding patterns; of these, nine were monomorphic among all genotypes surveyed and three showed some variation. Genetic analysis of the variable banding patterns observed for diaphorase, malate dehydrogenase, and peroxidase revealed the presence of single independently inherited loci, designated Dia-1, Mdh-1, and Per-1. These loci are inherited in a simple Mendelian manner and are useful as genetic markers in peach. Some possible applications to peach breeding are discussed.
Crossability of BC1 Aneuploid and Tetraploid Progeny Derived from Vaccinium ashei/corymbosum Pentaploid Hybrids
Authors: Vorsa Nicholi , Jelenkovic Gojko , Draper Arlen D. , Galletta Gene J.
Published: August 2022

V. corymbosum L./V. ashei Reade pentaploid blueberry hybrids backcrossed to tetraploid V. corymbosum yield tetraploids and aneuploids. Six BC1 derivatives, a tetraploid (2n = 4x = 48) and five multiple aneuploids (2n = 4x + 3, 4, 5, 8, and 9 = 51, 52, 53, 56, and 57) were selfed, intercrossed, and backcrossed to the V. corymbosum cv. Bluecrop. The fertility parameters measured were percent fruit set (FS), total seeds/berry (TS), developed seeds/berry (DS), percent developed seeds/berry (PDS), percent seed germination (PG), and number of seedlings (NS). Values of all parameters decreased as aneuploidy level of the cross (sum of extra chromosomes, number of chromosomes over 2n = 48, in the seed and pollen parent) increased; the relationship was principally linear. A significant quadratic relationship was noted for PDS. Diallel analysis revealed that reciprocal effects were significant for all parameters except PG and were the second most important factor contributing to variability among crosses for NS. All parameters indicated a high level of self sterility. Although the aneuploids in this study had reduced crossability, they can produce sizable progenies with practical efficiency. Contrary to previous reports, these results suggest that pentaploid hybrids and their BC1 derivatives can be used to facilitate gene transfer from V. ashei into V. corymbosum.
Growth Response and Weed Control in Slicing Cucumbers Under Row Covers
Authors: Hemphill Delbert D. , Crabtree Garvin D.
Published: August 2022

Five weed-control treatments (unweeded; hand-weeded; bensulide and naptalam; bensulide, naptalam, and paraquat; black polyethylene mulch) were combined factorially with three row-cover treatments (no cover, spun-bonded polyester, highly perforated polyethylene) in a 2-year experiment. Slicing cucumbers (Cucumis sativus L.) were transplanted 26 (1985) or 23 (1986) days after application of the bensulide-naptalam. This combination of herbicides provided weed control for up to 4 weeks after transplanting, but was less effective in 1986 than in 1985. Row covers reduced herbicide efficacy. Spraying paraquat through the covers 2 to 3 days before setting transplants significantly improved weed control and cucumber yield. Soil crusting was reduced, and earliness and total yield were enhanced by mulch and row covers. Greatest yields and estimated net economic return in both years occurred with row covers with mulch followed by mulch alone in 1986 and by mulch alone or hand-weeding with row covers in 1985. Weed control, earliness, and yield were not affected significantly by type of row cover in either year. Chemical names used: O,O-bis(1-methylethyl)-S-[2-(phenylsulfonyl)amino]ethyl]phosphorodithioate (bensulide); 2-[(1-napthalenylamino)carbonyl]benzoic acid (naptalam); 1,1′-dimethyl-4,4′-bipyridinium salts (paraquat).
Growth of Foliage Plants in Differentially Compacted Potting Media
Authors: Conover C.A. , Poole R.T.
Published: August 2022

Six potting media (Metro Mix 200, 300, 350, 500, 2 sedge peatmoss : 1 pine bark : 1 cypress shavings (by volume) and 3 sedge peatmoss : 1 mason sand (v/v) were compacted at 0, 0.1, 0.2, or 0.3 kg·cm−2. Noncapillary pore space was reduced in all media at 0.1 kg·cm−2 as compared to 0 pressure, but increasing compaction pressure had more effect on 2:1:1 than on 3:1 or Metro Mixes. Pilea pubescens Liebm. ‘Silver Tree’ and Dracaena sanderana Hort. Sander ex M. T. Mast. were used in two additional experiments where the six media were combined factorially with compaction pressures of 0.1 and 0.2 kg·cm−2 and irrigation rates of two or four applications/week. Both genera were affected more by potting media and irrigation levels than by compaction, with best plants generally produced in Metro Mixes receiving the higher irrigation level.
Outcrossing Rates in Pecan and the Potential for Increased Yields
Authors: Marquard Robert D.
Published: August 2022

Nuts produced from controlled crosses of ‘Western’ pecan [Carya illinoensis (Wangenh.) C. Koch] pollinated with ‘Wichita’ were 20% heavier and 12% larger by volume than self-pollinated nuts. The inherited biochemical marker of malate dehydrogenase was used to quantify outcrossing in a ‘Western’ orchard with ‘Wichita’ as the pollinator. The frequency of cross-pollination declined with distance from the pollinator, and the linear equation y = 53.9 − 6.1x was derived to estimate percent cross-pollination (y) in row (x) away from the pollinator. A model to estimate relative orchard production predicts maximum efficiency of a ‘Western’ orchard when the frequency of the pollinator is 25% to 33%. Nut quality of ‘Western’ field samples was positively related to percent cross-pollination of the sample. Cross-pollination under field conditions of ‘Western’ by ‘Wichita’ increased nut weight and volume 31% and 16%, respectively.