The influence of fruit thinning on fruit drop and quality of citrus

Different fruit thinning methods were tested on ‘Sensation’ mango trees over two seasons in a trial conducted in Northern Province, South Africa. The objective of the study was to select the best thinning intensity and method based on different parameters. Thinning was carried out in October prior to the occurrence of excessive natural fruit drop. When fruits were thinned to one and two fruits per panicle, fruit number, weight and yield per tree at harvest were all increased. When 50% of the panicles were thinned there was an increase in the fruit retention potential of the trees as well as in the size and quality of the fruit produced. Large fruits were, however, prone to certain physiological problems. Chemical thinning with Corasil.E produced very small fruits with an increased percentage of ‘mules’ (fruit without seed). Trees subjected to severe thinning intensities showed earlier recovery of starch reserves and better vegetative growth than the control.

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Consecutive wet days may impede fruit quality of peach and nectarine and cause fruit drop

Scientia Horticulturae ◽

10.1016/j.scienta.2021.110011 ◽

2021 ◽

Vol 282 ◽

pp. 110011

Author(s):

Georgios Pantelidis ◽

Theodoros Mavromatis ◽

Pavlina Drogoudi

Keyword(s):

Fruit Quality ◽

Fruit Drop

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Population dynamics of pre-imaginal stages of olive fruit fly Bactrocera oleae Gmel. (Diptera, Tephritidae) in the region of Bar (Montenegro)

Pesticidi i fitomedicina ◽

10.2298/pif1301023p ◽

2013 ◽

Vol 28 (1) ◽

pp. 23-29 ◽

Cited By ~ 2

Author(s):

Tatjana Perovic ◽

Snjezana Hrncic

Keyword(s):

Population Dynamics ◽

Developmental Stages ◽

Fruit Fly ◽

Bactrocera Oleae ◽

Yield Reduction ◽

Olive Fruit Fly ◽

Application Timing ◽

Olive Fruit ◽

Fruit Drop

Olive fruit fly is the most harmful pest of olive fruits and important for oil production. Damage involves yield reduction as a consequence of premature fruit drop, but also a reduced quality of olive oil and olive products. There is little available data regarding the biology of Bactrocera oleae in Montenegro. Knowledge of the pest life cycle and development would improve optimization of insecticide application timing and protection of fruits, and reduce adverse effects on the environment. Investigation was conducted on the Zutica variety in an olive grove located in Bar during a three-year period. Population dynamics of the pre-imaginal stages and level of fruit infestation were monitored from mid-July until the end of October. The results of this three-year investigation showed that the beginning of infestation was always at the end of July. It was also found that, depending on environmental conditions, the level of infestation was low until the end of August. In September and October it multiplied, and reached maximum by the end of October. Regarding infestation structure, eggs and first instar larvae were the dominant developmental stages of the pest until the middle of September. From mid-September until mid-October all developmental stages (eggs, larvae, pupae) were equally present in infested fruits. Pupae, cocoons and abandoned galleries prevailed until the harvest.

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Fruit Abscission and Fruit Quality of Apples Following Use of Dicamba to Control Preharvest Drop

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.115.3.390 ◽

1990 ◽

Vol 115 (3) ◽

pp. 390-394 ◽

Cited By ~ 2

Author(s):

Richard P. Marini ◽

Ross E. Byers ◽

Donald L. Sowers ◽

Rodney W. Young

Keyword(s):

Fruit Quality ◽

Starch Content ◽

Soluble Solids ◽

Naphthaleneacetic Acid ◽

Soluble Solids Content ◽

Fruit Abscission ◽

Fruit Drop ◽

Solids Content ◽

Methoxybenzoic Acid

Five apple (Malus domestica Borkh.) cultivars were treated with dicamba at concentrations of 0 to 200 mg·liter-1 during 3 years. Although the response varied with cultivar, dose, and year, dicamba always delayed fruit abscission. At similar concentrations, dicamba usually reduced fruit drop more than NAA, but less than fenoprop. Dicamba at 10 mg·liter-1 effectively delayed drop of `Delicious', whereas 20 to 30 mg·liter-1 was required for `Red Yorking', `Rome', `Winesap', and `Stayman'. Dicamba did not influence flesh firmness, soluble solids content, water core, or starch content at harvest or after storage. Chemical names used: naphthaleneacetic acid (NAA); 2-(2,4,5-trichlorophenoxy)propionic acid (fenoprop); 3,6dichloro-2-methoxybenzoic acid (dicamba).

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Heading of shoots and hand thinning of flowers and fruits on 'BRS Kampai' peach trees

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2017001100006 ◽

2017 ◽

Vol 52 (11) ◽

pp. 1006-1016 ◽

Cited By ~ 4

Author(s):

Paula Duarte de Oliveira ◽

Gilmar Arduino Bettio Marodin ◽

Gustavo Klamer de Almeida ◽

Mateus Pereira Gonzatto ◽

Daniel Chamorro Darde

Keyword(s):

High Frequency ◽

Prunus Persica ◽

Fruit Size ◽

Fruit Production ◽

No Production ◽

Full Bloom ◽

Fruit Thinning ◽

Heading Control ◽

Peach Trees

Abstract: The objective of this work was to evaluate the effect of shoot heading and of hand thinning in different development stages of flowers and fruits on the fruit production and quality of 'BRS Kampai' peach (Prunus persica) trees. The experiment was performed during three crop years, under the conditions of the “Depressão Central” region in the state of Rio Grande do Sul, Brazil, and the treatments were: T1, heading of half of the mixed shoot; T2, heading of one third of the mixed shoot; T3, flower thinning in the pink bud stage; T4, thinning at full bloom; T5, thinning of fruit with 5 mm; T6, thinning of fruit with 20 mm; and T7, no thinning or heading (control). Fruit production and quality were evaluated. Plants with no thinning were more productive, but showed high frequency of fruits with a diameter smaller than 60 mm. Shoot heading reduced production per tree and resulted in small-sized fruit. Thinning time did not affect production, and fruit size was greater when thinning was performed at the bloom stage. 'BRS Kampai' peach trees can be thinned starting at bloom, which provides greater fruit size, with no production loss.

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EFFECTS OF FRUIT THINNING TIMING AND DIFFERENT COMPLEMENTARY CULTURAL PRACTICES ON YIELD AND FRUIT QUALITY OF 'SPRINGCREST' PEACH CULTIVAR GROWN IN THE NORTHEAST OF THE PROVINCE OF BUENOS AIRES (ARGENTINA)

Acta Horticulturae ◽

10.17660/actahortic.2002.592.58 ◽

2002 ◽

pp. 429-435

Author(s):

G. Valentini ◽

L. Arroyo

Keyword(s):

Fruit Quality ◽

Buenos Aires ◽

Cultural Practices ◽

Peach Cultivar ◽

Fruit Thinning

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AVG, NAA, boron, and magnesium influence preharvest fruit drop and fruit quality of ‘Honeycrisp’ apples

Canadian Journal of Plant Science ◽

10.1139/cjps-2017-0170 ◽

2018 ◽

Vol 98 (3) ◽

pp. 741-752 ◽

Cited By ~ 2

Author(s):

Michelle H. Arseneault ◽

John A. Cline

Keyword(s):

Fruit Quality ◽

Starch Degradation ◽

Naphthaleneacetic Acid ◽

Full Bloom ◽

Ethylene Evolution ◽

Malus Domestica Borkh ◽

Fruit Drop ◽

Honeycrisp Apples ◽

Colour Development

Preharvest fruit drop (PFD) of apple (Malus domestica Borkh.) can cause significant losses resulting in up to 50% reduction in yield in some years. In a 2-yr study, ‘Honeycrisp’ trees were treated with six foliar treatments including 20 mg·L−1 1-naphthaleneacetic acid (NAA) 2 wk before anticipated harvest (WBAH), 125 mg·L−1 aminoethoxyvinylglycine hydrochloride (AVG) 4 WBAH, AVG plus NAA 2 WBAH, and repeat sprays of 200 mg·L−1 B, and 2000 mg·L−1 Mg applied 48–93 d after full bloom to evaluate their effect on PFD and fruit quality. Fruit drop associated with broken pedicels and physiological causes was monitored. During a year with ∼43% PFD on untreated control trees, AVG retained up to ∼35% and NAA retained up to ∼27% of the total fruit number, relative to the control trees. The combination of AVG plus NAA had similar PFD compared with AVG alone, while B and Mg were similar to the control. The proportion of PFD associated with broken pedicels was ∼5%. Aminoethoxyvinylglycine delayed starch degradation, ethylene evolution, and blush skin colour development of fruit. This study supports the use of AVG 4 WBAH and NAA 2 WBAH to manage ‘Honeycrisp’ PFD, which may offer economic advantages for growing quality apples. Foliar sprays of Mg or B failed to reduce PFD.

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Plant Size Influences Bell Pepper Seed Quality and Yield

HortScience ◽

10.21273/hortsci.28.8.809 ◽

1993 ◽

Vol 28 (8) ◽

pp. 809-811 ◽

Cited By ~ 3

Author(s):

Victor M. Sanchez ◽

F.J. Sundstrom ◽

N. Suzanne Lang

Keyword(s):

Seed Quality ◽

Plant Density ◽

Cultural Practices ◽

Plant Size ◽

Bell Pepper ◽

Pepper Plant ◽

Plant Spacing ◽

Fruit Thinning ◽

Plant Densities

This study investigated the influence of plant size, as determined by plant density, and fruit load variation on the production and quality of bell pepper (Capsicum annuum L.) seeds. Six-week-old `Resistant Giant no. 4' bell pepper seedlings were transplanted 15, 30, 45, and 60 cm apart. Plants spaced 45 cm apart were not thinned or were thinned to one or three fruit per plant. Pepper plants grown at low plant densities produced larger fruit and seeds that germinated faster and at higher percentages than plants grown at higher densities. Assimilate export rate (AER) increased linearly with plant spacing. At harvest, C exchange rate (CER) and AER of plants with nonthinned fruit loads were ≈ 300% and 500% higher, respectively, than those of plants with one or three fruit. Fruit thinning decreased CER and AER; however, seeds produced by plants with one or three fruit had significantly higher germination percentages than plants with full fruit loads. These observations suggest that the high CERS of smaller plants with nonthinned fruit loads may have been insufficient to compensate completely for the higher sink demands. Therefore, crop cultural practices that increase the ratio of pepper plant size to total fruit count may increase the quality of seeds produced by those plants.

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