Preharvest Application Of Ethephon Research Articles

Alleviation of Vascular Bundle Browning in the Japanese Pear ‘Rinka’ by Preharvest Application of Ethephon

Alleviation of Vascular Bundle Browning in the Japanese Pear ‘Rinka’ by Preharvest Application of Ethephon

Ripening and fruit quality of ‘Fortune’ plums treated by pre-harvest application of ripening stimulants

The use of plant growth regulators that increase ethylene production is a common strategy to anticipate fruit ripening, increase peel color, and reduce the number of collections to complete the harvest of the fruits. Besides, this strategy may come true as a helping technique for the farmers to reduce costs with manpower, increasing overall profitability. This work aimed to evaluate the application of several concentrations of ethephon, associated with boric acid, on the anticipation of ripening of ‘Fortune’ plums, cultivated in Serra Gaúcha region, South Brazil. The study was carried out in a commercial orchard during the 2018-2019 and 2019-2020 harvests. It was used a completely randomized design with six treatments and four replicates; each replicate was composed of four plants. The following parameters were evaluated: the amount of fruits collected in each harvest, average fruit mass, diameter, length, firmness, soluble solids content, titratable acidity, SS/TA ratio, total phenolic compounds, and total anthocyanins. According to the results, the application of ethephon was capable of hastening and homogenizing partially plum ripening, but it also caused a reduction of anthocyanin and phenolic compounds contents and fruit firmness. On the other hand, the application of boric acid increased fruit firmness. From an economic standpoint, the pre-harvest application of ethephon may be interesting to reduce manpower requirements during harvest by an earlier harvest and by reducing the number of harvest cycles.

Expression Pattern of Ethylene-Related Genes in Response to Preharvest Chemical Treatments during Development and Ripening of Mangosteen Fruit (Garcinia mangostana L.)

The expression of ethylene associated genes based on development stage from fruit set until harvest in mangosteen has not been studied yet in some previous studies. The objective of this study was to investigate the expression pattern of genes involved in ethylene biosynthesis, Gm-ACS, and Gm-ACO, and perception, Gm-ETR, from the stages of fruit set (Period I), fruit development (Period II), and maturation until ripening or harvesting (Period III). The results showed that ethylene biosynthetic genes on the Gm-ACO gene were correlated with ethylene production's climacteric pattern. Gm-ACO was up-regulated at the beginning of the fruit set and then decreased. Fruit at age 2 - 10 weeks after anthesis showed a decrease in the Gm-ACO gene's mRNA levels. Then, Gm-ACO expression re-appeared and increased at the fruitage 11 - 12 after the fruit set. At the harvest-stage, the fruit showed down-regulation at the lowest level of the Gm-ACO expression. Ethephon treatment at or beyond 24 h (threshold time) increased the mRNA levels of Gm-ACS, Gm-ACO, and Gm-ETR. In contrast, the 1-Methylcyclopropene (1-MCP) treatment under the threshold time resulted in undetectable expression in all ethylene-related genes. These data would be beneficial to elucidate the molecular mechanisms in the mangosteen fruit ripening process. In addition, preharvest application of ethephon or 1-MCP can induce or inhibit the gene expression of ethylene biosynthesis and perception.

Effect of pre-harvest application of ethephon on colouration and expression of ripening related genes in citrus fruit

ABSTRACT In citrus, post-harvest treatment with ethylene or ethephon in an airtight container frequently resulted in fruit calyx drying, browning and abscission, with a consequent reduction in commercial value. To avoid these problems, pre-harvest degreening with ethepnon was performed on ‘CARA CARA’ navel orange fruits. An earlier and deeper orange colour development was obtained after treatment, reflecting at higher lightness (L*) and a*/b* ratio. The total carotenoid content in flavedo significantly increased, paralleling with a remarkable decrease in chlorophyll content, while in flesh TSS, TA and Vc were all not affected. A transcriptome analysis revealed that 171 genes in flavedo were involved in ethylene-degreening. These ethylene-responsive genes were involved in photosynthesis, chloroplast biogenesis, sugar metabolism, secondary metabolism, and activation of regulatory processes, including transcription regulation and protein posttranslational modification. In the chlorophyll metabolism, a chlorophyllase gene was strikingly increased, indicating the role of ethylene in promoting chlorophyll degradation. While, the genes related to carotenoid metabolism did not show any significant expression change after ethephon treatments. In conclusion, our data showed that pre-harvest degreening was an effective method to accelerate colour improvement, and meanwhile created a solid foundation for future investigations on the molecular mechanism underlying degreening of orange fruits.

Preharvest application of ethephon and postharvest UV-B radiation improve quality traits of beetroot (Beta vulgaris L. ssp. vulgaris) as source of colourant

BackgroundBetanins have become excellent replacers for artificial red-purple food colourants. Red beet (Beta vulgaris L. spp. vulgaris) known as beetroot, is a rich source of betalains, which major forms are betanin (red to purple) and vulgaxanthin (yellow). Betalains and phenolic compounds are secondary metabolites, accumulation of which is often triggered by elicitors during plant stress responses. In the present study, pre-harvest applications of ethephon (an ethylene-releasing compound) and postharvest UV-B radiation were tested as elicitors of betalains and phenolic compounds in two beetroot cultivars. Their effects on quality parameters were investigated, and the expression of biosynthetic betalain genes in response to ethephon was determined.ResultsEthephon was applied as foliar spray during the growth of beetroot, resulting in increased betanin (22.5%) and decreased soluble solids contents (9.4%), without detrimental effects on beetroot yield. The most rapid accumulation rate for betanin and soluble solids was observed between 3 and 6 weeks after sowing in both untreated and ethephon-treated beetroots. Overall, the expression of the betalain biosynthetic genes (CYP76AD1, CYP76AD5, CYP76AD6 and DODA1), determining the formation of both betanin and vulgaxanthin, increased in response to ethephon treatment, as did the expression of the betalain pathway activator BvMYB1. In the postharvest environment, the use of short-term UV-B radiation (1.23 kJ m− 2) followed by storages for 3 and 7 days at 15 °C resulted in increased betanin to vulgaxanthin ratio (51%) and phenolic content (15%).ConclusionsThe results of this study provide novel strategies to improve key profitability traits in betalain production. High betanin concentration and high betanin to vulgaxanthin ratio increase the commercial value of the colourant product. In addition, lowering soluble solids levels facilitates higher concentration of beetroot colour during processing. Moreover, we show that enhanced betanin content in ethephon-treated beetroots is linked to increased expression of betalain biosynthetic genes.

Anticipation of 'ubá' mango ripening with preharvest ethephon application

Preharvest application of ethephon, a compound that releases ethylene when hydrolyzed, can anticipate and standardize mango harvesting. In this study, the effects of different doses of ethephon, applied at preharvest, on harvest anticipation of 'Ubá' mango were evaluated. On the 17th week after anthesis, 25 mango trees, five per treatment, were sprayed with ethephon at 0, 250, 500, 750 and 1000mg L-1, plus 0.5% of mineral oil. Five fruits from each plant were harvested daily until full ripening, and evaluated. Except, for dose 0mg L-1, in which six days after ethephon application (DAAE), harvest was carried out weekly up to 41DAAE The treated fruit presented a more intense flesh color than the non-treated, particularly at the doses of 500 and 750mg L-1. Fruit treated with 500, 750 and 1000mg L-1showed abrupt firmness reduction from the 1st DAAE and TSS higher than 18°Brix on the 6th DAAE. Non-treated fruit presented slower firmness reduction and reached 18°Brix on the 35th DAAE. The dose of 1000mg L-1 of ethephon resulted in premature fall and low fruit quality. Application of 500 or 750mg L-1 of ethephon allowed to anticipate and to standardize mango harvesting. These doses also allowed harvesting fruit with the best commercial quality and without the need of climatization after harvest.

Qualitative changes in pepino fruits following preharvest applications of ethephon

Ethephon sprayed directly onto pepino fruits ( Solanum muricatum Ait., Chilean clone CH8) at 1920 mg l −1 advanced colour changes and therefore earliness of the crop. Colour changes evaluated with a HunterLab colorimeter occurred more quickly in ethephon-treated fruits in which a*/ b* ratio changed soon after treatment and reached the highest values in treated fruits. Among four visually classified maturity groups, differences in some qualitative parameters ( a*, a*/ b*, soluble solids, taste and carbohydrate contents) were found, but not between control and treated fruits. There was no significant loss of flavour or other measured quality parameters in earlier-harvested ethephon-treated fruit.

Preharvest applications of ethephon reduce superficial scald of ‘Fuji’ and ‘Granny Smith’ apples in storage

In 1989 and 1990, preharvest applications of 2-chloroethyl phosphonic acid (ethephon) at dosages from 50–400 mg 1’1 were applied to ‘Fuji’ and ‘Granny Smith’ apples. In 1989, the greatest reduction in scald after storage on both ‘Fuji’ and ‘Granny Smith’, relative to the untreated control resulted from applying 400 mg 1−1 ethephon five weeks before harvest and was 45% and 55% of controls, respectively. On ‘Granny Smith’ 400 mg 1− was also effective when applied three weeks before harvest. In 1990, preharvest applications of ethephon at either 200 or 400 mg 1−1 reduced scald in both cultivars relative to the controls. Ethephon applied six weeks before harvest had no dosage effect on scald reduction after storage. There was no consistent effect on fruit maturity at harvest from any treatment in either year, and no effect on quality of fruit out of storage.

Preharvest Application of Ethephon and SADH on Ripening and Quality of Lowbush Blueberry Fruit1

Abstract Preharvest treatments with succinic acid-2,2-dimethylhydrazide (SADH) had no effect on the rate of ripening of fruit of lowbush blueberry (Vaccinium an-gustifolium Alt.). Ripening (color change) was accelerated in berries receiving 2.24 and 4.48 kg/ha (2 chloroethyl)phosphonic acid (ethephon). Ethephon at these rates accelerated fruit abscission 14 days after treatment The weight, size, soluble solids, pH, titratable acidity and keeping quality of berries were not affected by ethephon or SADH treatments.

Preharvest Application of Ethephon on Scald and Quality of Stored ‘Delicious’ Apples1

Abstract (2-Chloroethyl)phosphonic acid (ethephon) applied 3 weeks before normal harvest hastened most of the changes commonly associated with maturation and ripening of ‘Delicious’ apples. Red color development, increase in soluble solids, water core development and decreased susceptibility to storage scald were all hastened by the ethephon treatment.

Effect of pre-harvest applications of ethephon on leaf abscission, fruit drop and constituents of fruit juice in pomegranates

SummaryFive concentrations of ethephon (0, 500, 1000, 1500, 2000 ppm) were applied to Rabbab pomegranate trees 18 days before harvest. With increased ethephon concentrations the percentage soluble solids, pH, vitamin C content and soluble solids to acid ratio of the juice decreased significantly. However, leaf abscission, fruit drop and percentage acid of the juice increased. As the soluble solids to acid ratio is the best single chemical criterion of pomegranate ripening, it was concluded that ethephon applications delayed ripening, and that the observed fruit drop was a direct effect of ethephon rather than fruit ripening.