• Journal of Biosystems Engineering
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• v.17 no.4
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• pp.363-369
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• 1992

The aim of this study was to examine the blurring effects on performance of the experimental fruit grader in grading Fuji apples by size and coloration of the whole surface of individual apples. The grader consisted of a black/white image prcessing system, one camera, and utilized the algorithm developed for high speed sorting in the previous study. The results are summarized as follows : 1. With the algorithm developed in the previous study, it took 0.27~0.33 second in analyzing the size and coloration of an apple, and relative errors were within 3% for size and 1.3% for coloration. 2. The effect of blurring increased linearly with the conveying speed of apple and showed more significant effect on detection of coloration than on determining of size. 3. Considering the blurring effect, capacity of the experimental fruit grader was estimated to 7,500 apples per hour.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.182-186
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• 2014

• Korean Journal of Plant Resources
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• v.32 no.6
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• pp.677-682
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• 2019

Hand leaf thinning for improvement of fruit coloration and quality is one of the most labor-consuming works in Korean apple cultivation. The study was aimed at investigating whether foliar application of two chelate compounds (Cu-EDTA, Fe-EDTA) could defoliate effectively 'Hongro'/M.9 apple leaves and enhance fruit coloration and quality. At 30 days before harvest, foliar spray with two chelate compounds defoliated significantly the apple leaves. Chelate treatments did not affect the leaf chlorophyll content. High concentration of chelates decreased drastically photosynthetic rate of true leaves, and then it stayed in low levels, whereas low levels of chelates reduced sharply the photosynthetic rate but it was gradually restored over time. Cu-EDTA regardless of its concentration triggered higher defoliation compared to Fe-EDTA. Consequently, higher defoliation improved light interception of fruits and accumulated more anthocyanin. Particularly, Cu-EDTA could target mainly fruit cluster leaves which affect directly light interception of the fruits, i.e. more selective defoliants compared to Fe-EDTA. However, 3% Cu-EDTA rather defoliated excessively, accompanying with reduction of fruit weight and soluble solids. Therefore, our results suggest that 1% Cu-EDTA which defoliates properly the fruit cluster leaves could improve coloration and quality of 'Hongro'/M.9 apple fruits.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.240-248
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• 2016

The objective of this study was to determine the effect of exogenous abscisic acid (ABA) on the red coloration and endogenous ABA contents of apple fruit skins. ABA and fluridone (an ABA synthetic inhibitor, FD) was sprayed on 'Hongro' apple fruit skins at 107 days after full bloom (DAFB). Visual coloration and hunter's color values were not affected by the ABA and FD treatments. Anthocyanin contents in fruit skins increased similarly to hunter $a^*$ values of fruit skins, but ABA and FD did not affect its accumulations. Liquid chromatography analysis revealed that endogenous ABA contents in control fruit increased at first and then decreased from 12 hours after the treatment. ABA treatment increased ABA contents in fruit skins from 2 hour after the treatment and it lasted until the end of the treatments. FD decreased ABA contents in fruit skins from 6 hours after the treatment. ABA treatment increased MdNCED2 (an ABA biosynthetic gene), MdACO1 (an ethylene biosynthetic gene), and MdCHS and MdDFR expressions. However, MdUFGT expressions were not affected by ABA treatment.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.264-270
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• 2015

Tropical night phenomenon has been increasing due to global warming recently, it is expected that fruit quality of apples will decrease due to elevated night temperature condition. In the present study, fruit quality at maturity, periodic anthocyanin biosynthetic gene expression and sugar contents in leaves and fruit flesh were investigated to establish the physiological responses of 'Fuji' apples under high night temperature. The night temperature were treated with such as ambient (control), ambient $-4^{\circ}C$, and ambient $+4^{\circ}C$. After the treatment, high night temperature didn't affect fruit diameter, weight, and soluble sugar contents. Coloration of ambient $+4^{\circ}C$ was poor than that of control, however there was no significant difference between these genes expression of control and that of ambient $+4^{\circ}C$ treatment in the late coloration season. Increase of sorbitol and glucose contents at ambient $+4^{\circ}C$ in leaves were smaller than those at control, and then sorbitol and sucrose contents in fruit flesh at ambient $+4^{\circ}C$ were smaller than those at control. The cross section of leaves showed that there were no differences with the structure of parenchyma and epidermis tissues between the treatments, but starch granules in the palisade parenchyma cells decreased in high night temperature treatments. Consequently, high night temperature didn't affect the fruit quality, but changed sugar contents in leaves and fruit flesh, and suppressed coloration regardless of anthocyanin biosynthetic gene expression.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.213-221
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• 2018

We analyzed the skin coloration and anthocyanin composition of 'Kyoho' and 'Heukboseok' grape berries to determine the cause of poor coloring in 'Kyoho' berry skins under high temperature (HT) at veraison. Although the skin coloration inhibited in both 'Kyoho' and 'Heukboseok' berries under HT for 30 days from veraison, the total anthocyanin content in 'Heukboseok' berry skins increased to the level of control after the end of temperature treatment, but 'Kyoho' did not increase. Malvidin derivatives were most significantly reduced in 'Kyoho' berry skins, followed by those of delphinidin and petunidin. Among individual anthocyanins, diglucosides and acylated malvidin derivatives were most decreased in 'Kyoho' berry skins. Acylated and tri-hydroxylated anthocyanins were reduced more than those of non-acylated and dihydroxylated, respectively. All different types of anthocyanin components in 'Kyoho' berry skins decreased by HT, and they were similar to that of total anthocyanin. In 'Heukboseok' berry skins, accumulations of all different types of anthocyanins were inhibited by HT, and increased to the level of control after the end of the treatment. These results suggest that the poor coloration of 'Kyoho' under HT at veraison was not caused by the decrease of specific anthocyanins but because the whole anthocyanin biosynthesis was suppressed by HT.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.555-560
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• 2011

The objective of this study was carried out to investigate the proper plant growth regulator for increasing the number of flower, fruit set, and to enlarge the size of the berries in Ardisia pusilla. Flower bud formation was used rooted cutting, and fruit set, enlargement, and coloration of fruit were used with two years-old. $GA_3$ concentrations were treated with 0, 100, 200, or $400mg{\cdot}L^{-1}$. Flower bud formation was effective in $400mg{\cdot}L^{-1}$ $GA_3$ and it was 1.8 times greater than control. Plant growth regulators were applied by foliar spray at full bloom stage to increase the fruit set. As a result, $GA_3$ was the most effective for increasing fruit set. Also, auxins of 4-CPA (Tomatotone, Donbu hitech Co., Korea) and dichloprop triethanol amine (Antifall, Bayer Crop Science Co., Ltd., Korea) were effective. When $GA_3$ concentrations of 0.5 and $1.0mg{\cdot}L^{-1}$ were used, fruit set (%) reached to 70% and 77%, respectively. Effectiveness of $GA_3$ was 1.8 times greater than control. Also, auxins, dichloprop triethanol amine increased to about 7-12% during fruit setting, but cytokinin and anti-gibberellin were ineffective. To investigate the fruit enlargement and coloration, $GA_3$ was treated with 0.3, 0.6, and $1.2mg{\cdot}L^{-1}$. Fruit enlargement was achieved to about 15% by $GA_3$ $0.6mg{\cdot}L^{-1}$ when $GA_3$ was treated 3 times at the interval of 1 month per treatment when fruit size was about 2-3mm (after full-blooming two months). But anthocyanin contents for coloration of fruit skin were not significant according to $GA_3$ concentration. The results showed that $GA_3$ enhanced bud formation, fruit set and enlargement of fruit size in Ardisia pusilla.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.256-260
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• 2012

This study was carried out to improve the fruit color through ABA treatment and to determine the optimum harvest time for producing high quality fruits in 'Hongisul' grapes. Spraying of $1000 mg{\cdot}L^{-1}$ exogenous ABA at early verasion (70 days after full bloom, DAFB) brought increase of endogenous ABA and soluble solid contents and enhanced fruit coloration. So, it was possible to harvest ABA treated fruits from 85 days after full bloom (15 days after treatment) by accelerated anthocyanin content which increased continuously until 110 DAFB. An increase of soluble solid and decrease of total acidity appeared steadily with the onset of berry ripening. After 100 DAFB, soluble solid content and total acidity did not change significantly, but the berry firmness was suddenly decreased. Consequently, it was suggested that ABA treated fruits need to be harvested at about 100 DAFB because of their short period of marketing by over ripening. On the contrary, harvesting of untreated fruit was totally impossible at 85 DAFB because of their poor berry coloration. But it was possible to harvest them at 100 DAFB based on the soluble solid/acidity ratio, whereas the berry coloration was progressed poorly. On the other hand, the fruits harvested at 110 DAFB showed acceptable berry coloration but their berry firmness was dropped significantly coincide with overripening. Therefore, it was needed to develop an altered production system for improving coloration at around 100 DAFB in 'Hongisul' grapes.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.118-119
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• 2001

This experiment was carried out to examine the effects of foliar applications of 100 mg.L$^{-1}$ ethephon mixed with different calcium formulae (10,000 mg.L$^{-1}$ Clef-non, 2,000 mg.L$^{-1}$ Cell-bine, 2,000 mg.L$^{-1}$ Hicalux, and 2,000 mg.L$^{-1}$ calcium acetate monohydrate) on the rind coloration, defoliation and fruit quality of satsuma mandarin cultivated in the plastic greenhouse. Foliar applications of ethephon alone or in mixture with either Clef-non, Cell-bine, Hicalux or calcium acetate monohydrate demonstrated that increased 'a'value of peel chromaticity as compared to the control. The treatments encouraged fruit colour and allowed the harvest date to be predicted. The defoliation ratio decreased considerably by foliar applications of ethephon mixed with Cell-bine or Hicalux. The sugar content of fruit increased by 1.6, 1.54, and 1.54$^{\circ}$Bx with the foliar applications of ethephon, ethephon+Clef-non, and ethephon+Cell-bine, respectively. With the foliar applications of ethephon in mixture with Cell-bine, fruit coloration was accelerated. defoliation was delayed, and fruit quality was improved.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.156-161
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• 2011

This experiment was performed in order to define the characteristic and quality of the fruits set on primary and secondary shoots in 'Heukgoosul' grape. The numbers of flower clusters per shoot were 1.1 and 0.6 in primary shoots and secondary shoots, respectively. The fruits of primary shoot showed 12.1 g of higher berry weight than 8.9 g of the fruits set on secondary shoots. Fructose and glucose contents were significantly higher in the fruits of secondary shoots during veraison, but the levels gradually decreased, reaching a similar level with those of primary shoot at the harvest stage. The acid content decreased rapidly from day 50 after full bloom in both primary and secondary shoots, but the rate of decrease slowed down from day 70 after full bloom in secondary shoots. Berries of secondary shoots showed rapid increase of skin coloration during veraison and reached a high degree of coloration within a short period when compared with those of primary shoots.