Preliminary examination of thinning strategies on young ‘Jonagold’ and ‘Pink Lady’ apples

1997 ◽  
Vol 37 (3) ◽  
pp. 377 ◽  
Author(s):  
K. M. Jones ◽  
S. A. Bound ◽  
C. R. Summers ◽  
M. J. Oakford
Keyword(s):  
Fruit Size ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Naphthalene Acetic Acid ◽  
Fruit Firmness ◽  
Full Bloom ◽  
Quality Outcomes ◽  
Chemical Treatments ◽  
Combination Treatments ◽  
Preliminary Examination

Summary. Strategies were examined for thinning 5-year-old apple trees of ‘Jonagold’ and ‘Pink Lady’ with chemical thinners. Both cultivars were left unthinned (control), hand-thinned at 20 days after full bloom (DAFB) or chemically thinned. The chemical treatments consisted of full bloom (FB) sprays of naphthalene acetic acid (NAA) at 2.5, 5 or 10 mg/L or ethephon at 25, 50 or 100 mg/L or combination treatments of 2.5, 5 or 10 mg NAA/L at FB followed by 50 mg ethephon/L at 7 DAFB. In addition 5 mg NAA/L or 50 mg ethephon/L were followed by 150 mg CyLex/L (6-benzyladenine, Abbott Laboratories) at 20 DAFB. Neither NAA, ethephon alone or NAA followed by ethephon were effective at the 2 lower concentrations. The highest level of NAA with ethephon did some thinning of ‘Pink Lady’ but overthinned ‘Jonagold’. The CyLex combination treatments were the most effective. Combining NAA and CyLex did not thin enough to increase fruit size in ‘Pink Lady’ and slightly overthinned ‘Jonagold’. The most effective treatment of ethephon and CyLex removed about half the crop load compared with the control for both cultivars. This resulted in a 29% increase in fruit weight and a 48% increase in fruit size for ‘Jonagold’. ‘Pink Lady’ increases were less, being 16% for fruit weight and 38% for fruit size. All mean fruit weight and size outcomes for the ethephon–CyLex treatment exceeded provisional targets. The ethephon–CyLex combination had important fruit quality outcomes other than fruit weight and size. Fruit soluble solids were increased by this treatment by 10% for ‘Jonagold’ and 6% for ‘Pink Lady’ and fruit firmness by 11% for ‘Jonagold’ and 5% for ‘Pink Lady’. The overall results for the ethephon–CyLex combination were most encouraging for both cultivars. Further work is required to substantiate these results.

Integrating Cytolin into a chemical thinning program for red ‘Delicious’ apple

1997 ◽  
Vol 37 (1) ◽  
pp. 113
Author(s):  
S. A. Bound ◽  
K. M. Jones ◽  
M. J. Oakford
Keyword(s):  
Fruit Size ◽  
Soluble Solids ◽  
Naphthalene Acetic Acid ◽  
Consistent Difference ◽  
Fruit Firmness ◽  
Split Application ◽  
Full Bloom ◽  
Long Term Storage ◽  
Return Bloom ◽  
High Concentrations

Summary. The thinning efficiency of Cytolin and its interaction with the blossom thinner naphthalene acetic acid (NAA) and the post-bloom thinner CyLex (a formulation of 6-benzyladenine) were examined in a trial on Hi-Early red ‘Delicious’ apples in northern Tasmania. Cytolin was applied as either a single or split application at 4 concentrations (25, 40, 55, 70 mg/L). The split application was followed by a low rate of NAA at full bloom or by CyLex as a post-bloom thinner. While the higher concentrations of Cytolin achieved some thinning it was not sufficient. Satisfactory thinning levels, with a corresponding increase in fruit size, were achieved by the addition of either NAA or CyLex to the program. There was no consistent difference in thinning effect or fruit size between the single and split applications of Cytolin. High concentrations of Cytolin followed by NAA resulted in a high proportion of pygmy fruit but there were no pygmy fruit at the lower Cytolin rates. In general, split applications of Cytolin improved fruit typiness better than single applications. Cytolin alone had no effect on seed numbers, whereas addition of either NAA or CyLex to the program reduced seed numbers. Fruit firmness was improved by the CyLex treatments. Return bloom decreased with increasing concentration of Cytolin. Thinning and fruit quality can be improved with the recommended label rate of Cytolin (25 mg/L) applied as a split application (12.5 mg/L applied at king petal stage and 12.5 mg/L 3 days later) followed by 3 mg/L NAA at full bloom or by CyLex as a post-bloom thinner. The improvement in fruit firmness and increase in soluble solids by CyLex compared with NAA may make this combination preferable for long-term storage fruit although further assessment is needed.

Thinning Golden Delicious apples with pre-bloom naphthalene acetic acid and later carbaryl sprays

1984 ◽  
Vol 24 (126) ◽  
pp. 453 ◽  
Author(s):  
KM Jones ◽  
TB Koen ◽  
RJ Meredith
Keyword(s):  
Acetic Acid ◽  
Fruit Size ◽  
Fruit Weight ◽  
Naphthalene Acetic Acid ◽  
Full Bloom ◽  
Golden Delicious

A trial in southern Tasmania examined the thinning effects of naphthalene acetic acid (NAA) on Golden Delicious apples. The NAA was applied at pink bud or balloon blossom at 12, 18 and 24 ppm, with or without carbaryl at 1800 ppm applied 10 d after full bloom. Carbaryl was also applied alone 10 and 20 d after full bloom, and a hand thinned treatment was included. The higher concentrations of NAA did the most thinning but only the hand-thinned and 24 ppm NAA at balloon blossom with carbaryl treatment thinned enough to produce the required fruit size. The NAA sprays at balloon blossom thinned considerably more than those at pink bud. Neither NAA nor carbaryl alone was as effective as the combination. Reduction of fruit numbers increased mean fruit weight from 101 g in the control to 149 g in the 24 ppm NAA at balloon blossom with carbaryl. There was no evidence that increasing the concentration of NAA reduced mean fruit weight. This trial demonstrates that the effect of balloon stage sprays of NAA combined with later carbaryl sprays on Golden Delicious is similar to that achieved by the normal practice of spraying with NAA 7-14 d after full blossom, followed by carbaryl at 20 d. Reduction from 128 fruit/ 100 blossom clusters in the control to 76 after spraying at balloon blossom is still outside present aims of 30-50 fruit and is not considered to be severe enough thinning to assure adequate fruit size.

Control of pudding spot in Crofton apple

1992 ◽  
Vol 32 (4) ◽  
pp. 503
Author(s):  
KM Jones ◽  
SA Bound ◽  
MJ Oakford ◽  
TB Koen
Keyword(s):  
Acetic Acid ◽  
Fruit Size ◽  
Fruit Weight ◽  
The Other ◽  
Naphthalene Acetic Acid ◽  
Full Bloom ◽  
Apple Trees ◽  
Low Incidence ◽  
Thinning Effect

Regularly cropped Crofton apple trees in southern Tasmania were thinned using sprays of naphthalene acetic acid (NAA) at 10 mg/L or ethephon at 200 mg/L at balloon blossom (BB), full bloom (FB), 10 days after full bloom (DAFB) or 20 DAFB. These treatments were compared with hand thinning and an unthinned control. Ethephon had a uniformly mild thinning effect (about 30% compared to control), except at 10 DAFB, where no thinning occurred. NAA was inconsistent, thinning well at BB (50%), overthinning at both FB (85%) and 10 DAFB (88%), and underthinning at 20 DAFB (similar to the control). Ethephon applied at BB and FB increased both mean fruit weight (12 and 22%) and fruit size (28 and 79%), but later applications did not. NAA applications generally resulted in increased mean fruit weight and size, except for the 20 DAFB treatment, which was similar to the control. All ethephon treatments had a low incidence (43%) of pudding spot similar to the controls and hand-thinned treatments. Most NAA treatments showed significantly higher levels of pudding spot than the other treatments. It is concluded that ethephon is a more predictable thinner for Crofton than NAA, and its use to control pudding spot is recommended.

scholarly journals Tergitol TMN-6 for Thinning Peach Blossoms

HortScience ◽  
2004 ◽  
Vol 39 (7) ◽  
pp. 1611-1613
Author(s):  
B.S. Wilkins ◽  
R.C. Ebel ◽  
W.A. Dozier ◽  
J. Pitts ◽  
R. Boozer
Keyword(s):  
Relative Humidity ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Full Bloom ◽  
Fruit Number ◽  
Time Of Application ◽  
Chemical Treatments ◽  
Leaf Yellowing

This study was conducted to determine efficacy of Tergitol TMN-6 in thinning peach blossoms. A pretest was conducted and demonstrated no difference between TMN-6 and TMN-10 in efficacy when applied at full bloom or petal fall and at rates of 20 and 40 mL·L-1. In the main test, Tergitol TMN-6 was sprayed once at 10, 20, or 30 mL·L-1 at full bloom or petal fall and compared to an unsprayed control for 3 years. Tergitol caused widespread necrosis of flower parts including sepals, petals, pistils, stamens and peduncles. There was a difference among chemical treatments with more fruit removed at higher concentrations, although the amount of fruit removed was similar for the 20 and 30 mL·L-1 rates. There was no difference in thinning response at full bloom or petal fall, indicating a wide window of efficacy. There was also a difference among years, which was apparently not related to temperature or relative humidity during time of application. Tergitol caused some leaf yellowing and tip burn especially at the higher rates when leaves were present, but the trees did not appear to be seriously affected. Fruit weight was either not affected or larger in some years from treatment. Unlike higher concentrations, tergitol at 10 mL·L-1 did not negatively impact fruit number per tree at harvest. At harvest, fruit weight, skin blush, firmness, and soluble solids at harvest were not affected by treatment. Tergitol TMN-6 proved to be an effective thinning agent and when applied from full bloom to petal fall at 10 mL·L-1 it did not adversely affect the tree or fruit.

scholarly journals CPPU Influences Fruit Quality, Fruit Set, Return Bloom, and Preharvest Drop of Apples

HortScience ◽  
1993 ◽  
Vol 28 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Eric A. Curry ◽  
Duane W. Greene
Keyword(s):  
Fruit Set ◽  
Fruit Size ◽  
Fruit Weight ◽  
Linear Increase ◽  
Soluble Solids ◽  
Naphthalene Acetic Acid ◽  
Flesh Firmness ◽  
Application Rates ◽  
Solids Concentration ◽  
Return Bloom

CPPU was applied to whole spur `Delicious' apple (Malus domestica Borkh.) trees in central Washington at 0,6.25,12.5,25, or 50 mg·liter-1 at full bloom (FB) or FB plus 2 weeks. At both application times, the flesh firmness of treated fruit linearly increased with increasing concentration. CPPU applied at 0,5,10,15, or 20 mg·liter-1 to spur `Delicious' trees in Massachusetts at king bloom resulted in a linear increase in flesh firmness at harvest and following 28 weeks in air storage at 0C. CPPU did not affect the incidence of senescent breakdown, decay, or cork spot. Fruit length: diameter (L/D) ratios generally increased at all doses. Fruit weight was not influenced at either location. All CPPU concentrations reduced return bloom on `Delicious' apples in Massachusetts in 1989. Of the 10, 20, or 40 mg·liter-1 treatments for `Empire' apples, only CPPU at 40 mg·liter-1 reduced return bloom. CPPU applied to `Empire' apples in Massachusetts did not effect fruit set, soluble solids concentration, L/D, or firmness; however, fruit weight increased linearly with concentration. CPPU applied at 100 mg·liter-1 retarded preharvest fruit drop of `Early McIntosh' in Massachusetts for ≈7 days but was not as effective as NAA at 20 mg·liter-1. In a larger semicommercial trial, `Delicious' fruit treated with CPPU at 5,10, or 15 mg·liter-1 at FB, petal fall (PF), or PF plus 1 week, respectively, were harvested and graded over a commercial packing line. Malformities caused by CPPU at the highest doses reduced packout, although all CPPU application rates reduced the percent fruit culled due to poor color. CPPU increased packed fruit size, since the size of fruit (64 mm in diameter) in the >150-fruit/box size decreased, while the size of fruit (72 mm in diameter) in the 100- and 130-fruit/box sizes increased. Treated fruit stored for 7 months at 1C were firmer than nontreated controls. Chemical names used: N-(2-chloro-4-pyridyl)- N' -phenylurea (CPPU); 1 naphthalene-acetic acid (NAA).

scholarly journals Performance of an Elite Strawberry Population Derived from Wild Germplasm of Fragaria chiloensis and F. virginiana

HortScience ◽  
2010 ◽  
Vol 45 (8) ◽  
pp. 1140-1145 ◽  
Author(s):  
Travis L. Stegmeir ◽  
Chad E. Finn ◽  
Ryan M. Warner ◽  
James F. Hancock
Keyword(s):  
Fruit Size ◽  
Transgressive Segregation ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Linkage Drag ◽  
Fruit Firmness ◽  
Production Traits ◽  
Flower Number ◽  
Seasonal Flowering ◽  
Positive Correlations

Fragaria ×ananassa Duchesne ex Rozier, or the cultivated strawberry, resulted from the hybridization of two wild species, F. chiloensis (L.) Miller and F. virginiana Miller. In an attempt to recreate the cultivated strawberry, elite clones of F. chiloensis and F. virginiana were crossed within species and then hybridized to produce 26 reconstructed populations. Of these populations, FVC11 [(Frederick 9 × LH 50-4) × (Scotts Creek × 2 MAR 1A)] had unusually large fruit size and was selected for further analysis. In the summer of 2008, 78 individuals of this population were evaluated for their seasonal flowering patterns, inflorescence number, inflorescence height, crown production, flower number, fruit size, yield, internal color, soluble solids, fruit firmness, and plant vigor. Progeny means were compared with those of the parental means and most traits exhibited transgressive segregation, most notably yield and fruit weight. Significant positive correlations were found between many of the production traits, although there were significant negative correlations between fruit firmness and flower number per inflorescence, fruit firmness and soluble solids, and yield per plant and soluble solids. Overall performance scores were assigned to each genotype by summing their relative performance for each trait in the population. Individuals were identified that combined high values for fruit weight and yield with higher than average values for fruit color, firmness, and soluble solids. Use of this population in breeding programs could help expand the genetic base of the cultivated strawberry with limited linkage drag.

Blossom Thinning in Pome and Stone Fruit

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 553b-553
Author(s):  
Esmaeil Fallahi
Keyword(s):  
Fruit Size ◽  
Naphthalene Acetic Acid ◽  
Full Bloom ◽  
Flower Bud ◽  
Hydrogen Cyanamide ◽  
Ammonium Thiosulfate ◽  
The Past ◽  
Apple Cultivars ◽  
Ortho Cresol ◽  
Bud Initiation

Early thinning of apples is important because of its impact on fruit size and next season's flower bud initiation. In the past, apple cultivars were often sprayed with the blossom thinner sodium dinitro-ortho-cresol(Elgetol) during full bloom, followed by a post-bloom application of a fruit thinner such as carbaryl with or without naphthalene acetic acid (NAA). Elgetol was removed from the market in 1989 because of the high cost of re-registration. Full-bloom sprays of sulfcarbamide (Wilthin), pelargonic acid (Thinex), and endothalic acid (Endothal), ammonium thiosulfate (ATS) or petal fall spray of carbaryl (Sevin XLR Plus) were developed as replacements for Elgetol. Hydrogen cyanamide (HC) and other chemicals have been used to eliminate or to reduce chilling requirements of peaches grown under the warm desert conditions. HC applied at “pink bloom” stage was observed to reduce the number of open blooms in `Florda Prince' peach; therefore, it was first used for blossom thinning in this cultivar in Arizona. Later, HC was also found to be an effective blossom thinner for plums in Idaho. HC has recently been found to effectively thin apple and peach blossoms. Armothin has also been an effective blossom thinner for peach in California.

scholarly journals Higher Temperatures Decrease Fruit Size in Strawberry Growing in the Subtropics

Horticulturae ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 34
Author(s):  
Christopher Menzel
Keyword(s):  
Fruit Size ◽  
Negative Relationship ◽  
Titratable Acidity ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Marketable Yield ◽  
Significant Relationships ◽  
Small Fruit ◽  
Solids Content

Five strawberry (Fragaria × ananassa Duch.) cultivars were grown in Queensland, Australia to determine whether higher temperatures affect production. Transplants were planted on 29 April and data collected on growth, marketable yield, fruit weight and the incidence of small fruit less than 12 g until 28 October. Additional data were collected on fruit soluble solids content (SSC) and titratable acidity (TA) from 16 September to 28 October. Minimum temperatures were 2 °C to 4 °C higher than the long-term averages from 1965 to 1990. Changes in marketable yield followed a dose-logistic pattern (p < 0.001, R2s = 0.99). There was a strong negative relationship between fruit weight (marketable) and the average daily mean temperature in the four or seven weeks before harvest from 29 July to 28 October (p < 0.001, R2s = 0.90). There were no significant relationships between SSC and TA, and temperatures in the eight days before harvest from 16 September to 28 October (p > 0.05). The plants continued to produce a marketable crop towards the end of the season, but the fruit were small and more expensive to harvest. Higher temperatures in the future are likely to affect the economics of strawberry production in subtropical locations.

scholarly journals Daminozide, Root Pruning, Trunk Scoring, and Trunk Ringing Effects on Fruit Ripening and Storage Behavior of `McIntosh' Apple

1991 ◽  
Vol 116 (2) ◽  
pp. 195-200 ◽  
Author(s):  
D.C. Elfving ◽  
E.C. Lougheed ◽  
R.A. Cline
Keyword(s):  
Ethylene Production ◽  
Fruit Size ◽  
Soluble Solids ◽  
Starch Hydrolysis ◽  
Root Pruning ◽  
Full Bloom ◽  
Ethylene Evolution ◽  
Flesh Firmness ◽  
Solids Concentration ◽  
Storage Behavior

A midsummer foliar daminozide (DZ) application (750 mg a.i./liter) to `Macspur McIntosh'/M.7 apple trees (Malus domestics Borkh.) reduced preharvest drop and retarded flesh firmness loss and starch hydrolysis when tested at harvest; DZ also reduced fruit ethylene production at harvest and after 19 weeks of storage at 0.5C. Root pruning at full bloom (May) resulted in increased soluble solids concentration (SSC) and firmer flesh and less starch hydrolysis at harvest, but not consistently each year. Full-bloom root pruning reduced the incidence of stem-cavity browning and brown core, but again not each year. Full-bloom root pruning did not influence ethylene evolution at harvest but did reduce post-storage ethylene evolution in two of three seasons. Full-bloom root pruning generally was less effective than DZ in altering fruit behavior, while root pruning later than full bloom had virtually no effect. Trunk scoring or ringing increased SSC and retarded loss of flesh firmness before harvest and following storage, but had little effect on starch hydrolysis. Scoring or ringing decreased incidence of some disorders and reduced post-storage ethylene evolution, although these treatments had little effect on ethylene production at harvest. Trunk scoring influenced some fruit characteristics more strongly than DZ. Fruit size was not affected by any treatment in any year. Chemical name used: butanedioic acid mono (2,2 -dimethylhydrazide) (daminozide).

scholarly journals Physico-chemical characteristics of pomegranate accessions from the Kurdistan region, Iraq

2018 ◽  
Vol 63 (4) ◽  
pp. 355-366
Author(s):  
Saadatian Mohammad ◽  
Paiza Abdurahman ◽  
Kanar Salim ◽  
Pershang Younis ◽  
Hewen Abdurahman ◽  
...  
Keyword(s):  
Fruit Size ◽  
Chemical Properties ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Kurdistan Region ◽  
Fresh Weight ◽  
Fruit Length ◽  
Physico Chemical ◽  
Fruit Diameter

Some physico-chemical properties of ten pomegranate accessions collected from different districts in the Kurdistan region of Iraq were investigated in this paper. Considerable correlations between the characteristics studied were found and valuable pomological traits were observed. Cluster analysis showed the homonyms between some pomegranate accessions. Principle component analysis reported that the component describing the greatest variability also positively correlated with fruit weight, total aril weight, total peel weight, volume of juice, total soluble solids (TSS), fruit length, fruit diameter, pH, aril length, and 100-seed fresh weight, but negatively correlated with titratable acidity (TA). Fruit weight was firmly correlated with total aril weight, total peel weight, volume of juice, TSS, aril length, 100-seed fresh weight, fruit length and fruit diameter. The volume of juice was correlated with TSS, aril length, 100-seed fresh weight, fruit length, fruit diameter and it was observed that with an increase in the fruit size, the volume of juice increased as well. The correlation between total phenolic compounds and antioxidant capacity was not observed. The associations found among physical and chemical traits suggest that consumers should use large fruits with large arils so that they have more juice. Thus, ?Choman?, ?Raniyeh? and ?Halabja? were juicier than other accessions.

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