scholarly journals Soybean Oil as a Prebloom Flower Bud Thinner for Peaches

HortScience ◽  
1998 ◽  
Vol 33 (4) ◽  
pp. 600c-600
Author(s):  
Gregory L. Reighard ◽  
David R. Ouellette
Keyword(s):  
Soybean Oil ◽  
Fruit Size ◽  
Fruit Weight ◽  
Late Winter ◽  
Flower Buds ◽  
Flower Bud ◽  
Cold Temperatures ◽  
Fruit Maturity ◽  
Flower Phenology ◽  
Peach Orchard

Survival of peach flowers during spring or winter freezes and large fruit size at harvest are critical for profitable peach production in the Southeast. Delaying both bud swell in late winter and flower phenology in spring reduces the risk of flower bud death from cold temperatures. Preliminary research in Tennessee using soybean oil (SO) as a dormant oil spray in place of Superior oil showed SO delayed peach bloom, thinned flower buds, and increased fruit size. In 1997, a `Harvester' peach orchard in Monetta, S.C., and a `Redhaven' orchard near Clemson, S.C., were sprayed in early February with 0%, 6%, 8%, 10%, and 12% SO mixed with 1% (by volume) Latron B-1956. Number of dead flower buds and the flower bud stages for each SO treatment were recorded during the first pink to full bloom flowering period. Excess fruit were hand-thinned in late April. Fruit set, maturity date, weight, and yield/tree were taken. Bud death increased from 14% (control) to 17% to 20% at the 8%, 10%, and 12% SO rates for `Redhaven' and from 13% (control) to 21% at the 10% and 12% rates for `Harvester'. Phenology was delayed 3-4 days for `Redhaven' at 8%, 10%, and 12% SO, but no differences were noted in the `Harvester' trees. No differences in fruit maturity occurred. Fruit weight and yield/tree was higher for all `Harvester' SO treatments and the `Redhaven' 10% and 12% SO treatments. No shoot phytotoxicity was observed.

Thinning Peaches with Dormant Applications of Soybean Oil

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 496d-496
Author(s):  
R.E. Moran ◽  
D.E. Deyton ◽  
C.E. Sams ◽  
J.C. Cummins ◽  
A.L. Lancaster
Keyword(s):  
Soybean Oil ◽  
Yield Loss ◽  
Flower Buds ◽  
Flower Bud ◽  
Fruit Maturity ◽  
Before And After

Dormant applications of 0% to 20% soybean oil were tested as a prebloom thinner of `Georgia Belle' and `Redhaven' peach flower buds. Five separate experiments were conducted with soybean oil applied in late Jan. or early Feb. 1992, 1993, 1995, and 1997. The number of living and dead flower buds was counted on five or 10 shoots per tree before and 1 month after application in Expts. 1, 2, 3, and 4. In Expt. 5, buds were counted on two to three shoots per tree before and after a freeze of –4 °C during petal fall. Soybean oil thinned flower buds in all five experiments. The amount of flower bud death was concentration dependent with maximum bud kill of 53% occurring with application of 12% oil. Thinning was fairly consistent from year to year, ranging from 34% to 51% when 10% oil was applied, but was less uniform when 5% oil was applied and ranged from 6% to 40%. Overthinning occurred in Expt. 3 by all oil concentrations tested. Bud death in untreated trees was 40% in this experiment indicating that no thinning was needed. Mild to moderate spring freezes occurred in Expts. 2, 4, and 5, but did not result in greater yield loss in thinned than untreated trees. Soybean oil at 10% and 12% resulted in greater flower bud survival of a freeze in Expt. 5. Dormant applications of soybean oil thinned flower buds, reduced the amount of hand thinning and hastened fruit maturity.

scholarly journals Applying Soybean Oil to Dormant Peach Trees Thins Flower Buds

HortScience ◽  
2000 ◽  
Vol 35 (4) ◽  
pp. 615-619 ◽  
Author(s):  
Dennis E. Deyton ◽  
Renae E. Moran ◽  
Carl E. Sams ◽  
John C. Cummins
Keyword(s):  
Soybean Oil ◽  
Prunus Persica ◽  
Flower Buds ◽  
Flower Bud ◽  
Spring Frost ◽  
Fruit Maturity ◽  
Peach Trees

Applications of soybean oil to dormant peach [Prunus persica (L.) Batsch] trees were tested for prebloom thinning of flower buds in five separate experiments. Data were combined from experiments in which 2.5% to 20% emulsified soybean oil was sprayed on `Belle of Georgia' or `Redhaven' trees. The number of dead flower buds was concentration-dependent with maximum bud kill of 53% occurring with application of 12% soybean oil. The amount of thinning was fairly consistent from year to year, ranging from 34% to 51% when 10% soybean oil was applied, but was less consistent when 5% was applied, ranging from 6% to 40%. Overthinning by midwinter applications of soybean oil occurred in one experiment when bud mortality on nontreated trees was 40% due to natural causes. Mild to moderate spring freezes occurred in three experiments, but did not reduce yield more in soybean oil–thinned than in nontreated trees. Flower bud survival was improved when trees were sprayed with 10% or 12% soybean oil prior to a –4 °C spring frost. Applications of soybean oil to dormant trees thinned flower buds, reduced the amount of hand thinning required, and hastened fruit maturity.

scholarly journals Comparison of Soybean Oil and Ammonium Thiosulfate for Peach Bloom Thinning in a Short Bloom Duration Year

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 583c-583
Author(s):  
William C. Olien
Keyword(s):  
South Carolina ◽  
Soybean Oil ◽  
Fruit Set ◽  
Fruit Size ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Maximum Effect ◽  
Flower Bud ◽  
Ammonium Thiosulfate ◽  
Dormant Season

Dormant application of soybean oil formulations (SBO) effectively thin peach flower buds and delay bloom. Alternatively, thinners applied at bloom, such as ammonium thiosulfate (ATS), must be applied before pollination is complete. Consistent thinning with ATS is complicated by bloom duration and weather at bloom. Overall, 1995 peach bloom in South Carolina was delayed and progressed rapidly from 20% to 90% bloom in 2 days. Under these conditions, we compared thinning response of control (untreated), ATS (2%) applied at 70% bloom, SBO concentrations (2.5%, 5%, 7.5%, or 10%) applied 3 weeks before bloom (WBB), and application time of 5% SBO (1, 2, or 3 WBB). SBO was not available for applications earlier than 3 WBB. Treatments were applied by hand gun to six replications of single-tree plots of Redhaven. ATS had no effect on fruit set, yield, or fruit size, contrary to normal bloom years. Flower bud death increased linearly from 8% to 28% with increasing rate of SBO. Delay in SBO application decreased bud death. SBO at 5%-10% rates caused minor delay of 50% bloom, did not effect bloom duration, and increased mean fruit weight over control. Maximum effect was achieved with 10% SBO, reducing fruit number/ha and firmness by 72% and 18% and increasing fruit weight and soluble solids by 67% and 5% from control, respectively. Results show the advantage of bud thinning with SBO during the dormant season in a short bloom duration year.

scholarly journals THE RELATIONSHIP BETWEEN SWEET CHERRY FLOWER BUD DEVELOPMENT AND FRUIT QUALITY

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 668b-668
Author(s):  
Preston K. Andrews ◽  
Shulin Li ◽  
Margaret L. Collier
Keyword(s):  
Negative Correlation ◽  
Sweet Cherry ◽  
Prunus Avium ◽  
Fruit Size ◽  
Significant Negative Correlation ◽  
Flower Buds ◽  
Flower Bud ◽  
Bud Development ◽  
The Relationship ◽  
Flower Bud Development

The development of sweet cherry (Prunus avium L., `Bing') flower buds from winter through anthesis was examined. Shoots were collected from the top and bottom of the canopy. The weight and size of flower buds and primordia produced on last-season's and 1-year-old wood were measured. As early as mid-December bud and primordia size and weight were greater on last-season's wood than on 1-year-old wood, with the largest and heaviest buds and primordia produced on last-season's wood in the bottom of the canopy. There was a significant negative correlation between the number of primordia per bud and primordium weight. The relationship between flower bud and primordia size during mid-December and ovary size at anthesis suggests a causal relationship, which may be a major source of variation influencing harvested fruit size and quality.

scholarly journals Regulating Budbreak, Flowering, and Fruit Maturity in Sweet Cherry (Prunus avium L.) cv. `Bing' by Surfactant and Nitrate Applications

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 603e-603
Author(s):  
K.G. Weis ◽  
S.M. Southwick ◽  
J.T. Yeager ◽  
W.W. Coates ◽  
Michael E. Rupert
Keyword(s):  
Sweet Cherry ◽  
Prunus Avium ◽  
Fruit Set ◽  
Fruit Size ◽  
Calcium Nitrate ◽  
Potassium Nitrate ◽  
Fruit Weight ◽  
Full Bloom ◽  
Fruit Maturity ◽  
Flower And Fruit Development

The years 1995 and 1996 were low chill years in California with respect to stone fruit dormancy. Advancing reproductive budbreak and flowering was accomplished in `Bing' cherry (Prunus avium) by single-spray treatments of a surfactant {a polymeric alkoxylated fatty amine [N,N-bis 2-(omega-hydroxypolyoxyethylene/polyoxypropylene) ethyl alkylamine]} and potassium nitrate in combination when applied at “tightbud,” ≈ 42 days (1 Feb. 1995) before full bloom and with surfactant and potassium nitrate in combination when 10% green calyx was apparent, 33 days before full bloom. Applying 2% surfactant (v/v) + 6% potassium nitrate (w/v) was most effective in advancing bloom, speeding progression through bloom, and advancing fruit maturity when applied at tightbud stage. Surfactant (2% or 4%) applied with 25% or 35% calcium nitrate (w/v) on 2 Feb. 1996 significantly advanced full bloom compared to nontreated controls. Fruit maturity (1995) was somewhat advanced by surfactant–nitrate treatments, but fruit set and final fruit weight were equivalent among treatments. No phytotoxicity was noted in foliage or fruit. In California, marginal and insufficient winter chilling often causes irregular, extended, or delayed bloom periods, resulting in poor bloom-overlap with pollenizers. As a result, flower and fruit development may be so variable as to have small, green and ripe fruit on the same tree, making harvest more time consuming and costly. Data indicate that this surfactant, in combination with a nitrogenous compound, has potential to advance reproductive budbreak and advance maturity in sweet cherry without reducing fruit set or fruit size. Advancing the ripening time of sweet cherry even 2 to 3 days can increase the price received per 8.2-kg box by $10 to $20.

scholarly journals 614 PB 290 FLOWER BUD POSITION DETERMINES BLOOM AND FRUIT CHARACTERISTICS IN `ROME BEAUTY' APPLE

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 520b-520
Author(s):  
Randy R. Lee ◽  
John K. Fellman ◽  
Esmaeil Fallahi
Keyword(s):  
Fruit Quality ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Flower Buds ◽  
Flower Bud ◽  
Terminal Flower ◽  
Fruit Maturity ◽  
Lateral Bud ◽  
Bud Position ◽  
Lateral Flower

The influence of flower bud position on bloom, fruit quality, and fruit maturity was investigated on `Rome Beauty' apple (Malus domestica Borkh.). Limbs on trees containing spur terminal flower buds and lateral flower buds were tagged and the number of blossoms counted every three days until bloom ended. At harvest, fruit from each bud type were selected and seed number, fresh weight, fruit quality characteristics, and onset of ethylene production were measured. Spur terminal flower buds began blooming earlier, blossomed for a longer period of time, and produced more blossoms than lateral flower buds. Fruit from spur terminal flower buds had more seeds, were heavier, and contained more starch than lateral bud fruit. Lateral bud fruit had higher pressure values, due to smaller size, and higher soluble solids, due to consumption of starch reserves. Fruit color and titratable acidity were not significantly different regardless of bud position. Spur terminal fruit started producing ethylene eight days later than lateral bud fruit, indicating they were maturing less quickly. Cultivars such as `Fuji', `Gala', and `Braeburn' display similar growth and fruiting habits.

scholarly journals Field Applications of Fungicides Improve Quality and Size of Some Pumpkin Cultivars

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 676a-676
Author(s):  
Charles A. McClurg
Keyword(s):  
Cucurbita Pepo ◽  
Fruit Size ◽  
Poor Quality ◽  
Fruit Weight ◽  
Marketing Strategies ◽  
Fungal Diseases ◽  
Didymella Bryoniae ◽  
Erysiphe Cichoracearum ◽  
Fruit Maturity ◽  
General Benefit

Commercial producers of pumpkin (Cucurbita pepo) in the mid-Atlantic region frequently experience losses of fruit size and quality from the fungal diseases powdery mildew (Erysiphe cichoracearum) and black rot (Didymella bryoniae). In addition to loss of fruit size in some cultivars, the diseases can result in poor quality handles (fruit stems) and pre- and postharvest decay. Since the pumpkins are grown for ornamental use, their appearance, size, and quality are important in marketing strategies. Applications of recommended fungicides during the growing season, although costly, reduce losses in fruit size and quality in susceptible cultivars during years in which the pathogens become established prior to fruit maturity. Larger-fruited cultivars, in general, benefit more from fungicide application than smaller-fruited types in fruit weight, although both benefit in improved handle quality. Cultivars with apparent tolerance to fungal diseases are identified for producers who choose not to use fungicides.

scholarly journals Production and Postharvest Characteristics of Rosa hybrida L. `Meijikatar' Grown in Pots under Carbon Dioxide Enrichment

1993 ◽  
Vol 118 (5) ◽  
pp. 613-617 ◽  
Author(s):  
David G. Clark ◽  
John W. Kelly ◽  
Nihal C. Rajapakse
Keyword(s):  
Carbon Dioxide ◽  
Root Growth ◽  
Chlorophyll Concentration ◽  
Early Spring ◽  
Rosa Hybrida ◽  
Late Winter ◽  
Carbon Dioxide Enrichment ◽  
Flower Buds ◽  
Flower Bud ◽  
Leaf Chlorosis

The effects of carbon dioxide enrichment on growth, photosynthesis, and postharvest characteristics of `Meijikatar' potted roses were determined. Plants were grown in 350, 700, or 1050 μl CO2/liter until they reached 50% flower bud coloration and then were placed into dark storage for 5 days at 4 or 16C. Plants grown in 700 or 1050 μl CO2/liter reached the harvest stage earlier and were taller at harvest than plants produced in 350 μl CO2/liter, but there were no differences in the number of flowers and flower buds per plant among CO2 treatments. Plants grown in early spring were taller and had more flowers and flower buds than plants grown in late winter. Shoot and root growth of plants grown in 700 or 1050 μl CO2/liter were higher than in plants produced in 350 μl CO2/liter, with plants grown in early spring showing greater increases than plants grown in late winter. Immediately after storage, plants grown in 350 μl CO2/liter and stored at 4C had the fewest etiolated shoots, while plants grown in 1050 μl CO2/liter and stored at 16C had the most. Five days after removal from storage, chlorophyll concentration of upper and lower leaves had been reduced by ≈50% from the day of harvest. Carbon dioxide enrichment had no effect on postharvest leaf chlorosis, but plants grown in early spring and stored at 16C had the most leaf chlorosis while plants grown in late winter and stored at 4C had the least leaf chlorosis.

scholarly journals Flower Bud Density Affects Vegetative and Fruit Development in Field-grown Southern Highbush Blueberry

HortScience ◽  
1999 ◽  
Vol 34 (4) ◽  
pp. 607-610 ◽  
Author(s):  
B.E. Maust ◽  
J.G. Williamson ◽  
R.L. Darnell
Keyword(s):  
Leaf Area ◽  
Fruit Development ◽  
Fruit Size ◽  
Dry Weight ◽  
Vaccinium Corymbosum ◽  
Soluble Solids ◽  
Highbush Blueberry ◽  
Flower Buds ◽  
Flower Bud ◽  
Southern Highbush

Floral budbreak and fruit set in many southern highbush blueberry (SHB) cultivars (hybrids of Vaccinium corymbosum L. with other species of Vaccinium) begin prior to vegetative budbreak. Experiments were conducted with two SHB cultivars, `Misty' and `Sharpblue', to test the hypothesis that initial flower bud density (flower buds/m cane length) affects vegetative budbreak and shoot development, which in turn affect fruit development. Flower bud density of field-grown plants was adjusted in two nonconsecutive years by removing none, one-third, or two-thirds of the flower buds during dormancy. Vegetative budbreak, new shoot dry weight, leaf area, and leaf area: fruit ratios decreased with increasing flower bud density in both cultivars. Average fruit fresh weight and fruit soluble solids decreased in both cultivars, and fruit ripening was delayed in `Misty' as leaf area: fruit ratios decreased. This study indicates that because of the inverse relationship between flower bud density and canopy establishment, decreasing the density of flower buds in SHB will increase fruit size and quality and hasten ripening.

scholarly journals Influence of Blossom and Fruit Thinning on Peach Flower Bud Tolerance to an Early Spring Freeze

HortScience ◽  
1994 ◽  
Vol 29 (3) ◽  
pp. 146-148 ◽  
Author(s):  
Ross E. Byers ◽  
R.P. Marini
Keyword(s):  
Prunus Persica ◽  
Fruit Set ◽  
Unit Length ◽  
Early Spring ◽  
Late Winter ◽  
Flower Buds ◽  
Flower Bud ◽  
Cross Sectional ◽  
Fruit Thinning ◽  
Crop Density

Peach trees [Prunus persica (L.) BatSch.] blossom-thinned by hand were overthinned due to poor fruit set of the remaining flowers; however, their yield was equivalent to trees hand-thinned 38 or 68 days after full bloom (AFB). Blossom-thinned trees had three times the number of flower buds per unit length of shoot and had more than two times the percentage of live buds after a March freeze that had occurred at early bud swell the following spring. Blossom-thinned trees were more vigorous; their pruning weight increased 45%. For blossom-thinned trees, the number of flowers per square centimeter limb cross-sectional area (CSA) was two times that of hand-thinned trees and four times that of the control trees for the next season. Fruit set of blossom-thinned trees was increased four times. Flower buds on the bottom half of shoots on blossom-thinned trees were more cold tolerant than when hand-thinned 68 days AFB. Fruit set per square centimeter limb CSA was 400% greater the following year on blossom-thinned trees compared to controls. Removing strong upright shoots on scaffold limbs and at renewal points early in their development decreased dormant pruning time and weight and increased red pigmentation of fruit at the second picking. The number of flower buds per unit shoot length and percent live buds after the spring freeze were negatively related to crop density the previous season for trees that had been hand-thinned to varying crop densities at 48 days AFB. According to these results, blossom thinning and fruit thinning to moderate crop densities can influence the cold tolerance of peach flower buds in late winter.

Sign in / Sign up

Export Citation Format

Share Document