Session 02 Hormone metabolism and action

Journal of Berry Research, 2018

BACKGROUND: Blueberry was introduced as a crop in Argentina about 30 years ago. Its harvesting period ranges from September to December, during the northern hemisphere (its main export destination) fall season, which makes it a profitable commercial crop. As most part of the production is exported fresh, the understanding of biochemical aspects connected with fruit firmness is crucial to improve marketable conditions. OBJECTIVE: The main purpose of this work is to explore the metabolic and physiologic changes in three highbush blueberry cultivars during maturation and the possible association with their contrasting firmness features. METHODS: Vaccinium corymbosum cv. ‘Emerald’, ‘Snowchaser’ and ‘O’Neal’, in order of decreasing firmness, were collected at green and ripe stages. Metabolites were analyzed by gas chromatography-mass spectrometry (GC-MS) and HPLC. Total phenolic compounds, pectin methyl esterase (PME) and β-galactosidase activities were quantified by colorimetric assays....

Acta Horticulturae, 2018

13 14 Fresh Chilean blueberries take in average 20-50 days to reach overseas markets, so a better 15 knowledge of their postharvest behavior would help maintaining their quality for longer periods. Quality 16 of highbush blueberries (Vaccinium corymbosum L., cv. 'Duke' and 'Brigitta') was assessed at six stages 17 based on color: 100% green (100G), 75% green+25% pink (25P), 50% green+50% pink (50P), 25% 18 green+75% pink-blue (75B), 90-100% blue (100B), 100% blue+5 extra days on plant (100B+5). Also, 19 75P, 100B and 100B+5 fruit were evaluated after storage at 2 °C for 45 days + 1d at 18 °C. Over berry 20 maturation from 100G to 100B, color developed steadily while firmness and TA decreased. Respiration 21 and ethylene production rates peaked early, at 25P and 50P, respectively, and were higher for 'Duke' than 22 for 'Brigitta'. After harvest, cultivar-and maturity-related differences were found. 'Brigitta' fruit retained 23 higher firmness and had lower weight loss than 'Duke'. In general, 100B+5 fruit were over-ripe and 24 showed low quality. Additional physiological, morphological and biochemical studies for a wider range of 25 cultivars will be needed.

Fruits, 2011

Physiochemical changes in sunberry (Physalis minima L.) fruit during growth and ripening. Abstract-Introduction. Physalis minima is a widespread, quick-growing and high fruit-yielding annual herb belonging to the family Solanaceae. However, like many other underutilized fruit-bearing plants, P. minima is poorly studied and its nutritional potential is unknown. Since the edible sunberry is said to be a rich source of vitamin C, we studied the physiochemical changes during its fruit growth and ripening. Materials and methods. The changes in the physiochemical properties, such as pH, total soluble solids, titrable acidity, chlorophylls, carotenoids, carbohydrates (reducing sugars, non-reducing sugars, total sugars and starch), free amino acids, total proteins, total phenols, ascorbic acid, ethylene, and respiration and the activities of hydrolytic enzymes (amylase and invertase), antioxidant enzymes (catalase and peroxidase), and cell wall-degrading enzymes (cellulase, polygalacturonase and pectinmethylesterase), were analyzed in the fruit of sunberry at five sequential stages, viz., the young, premature, mature, preripe and ripe stages. Results and discussion. A gradual increase in the pH and total soluble solids occurred throughout the growth and ripening of sunberry fruit, while its titrable acidity increased up to the preripe stage and thereafter declined. A decreasing trend in the chlorophylls occurred simultaneously with an increase in the quantity of carotenoids. As the sunberry fruit proceeded towards ripening, the amount of its total starch decreased, with a concomitant sharp increase in the quantity of its reducing sugars, non-reducing sugars and total sugars. An increase in the quantity of free amino acids, proteins and phenols also occurred during the growth and ripening of the fruit, and the quantity of ascorbic acid increased at the mature stage. Moreover, sunberry fruit also exhibits a climacteric behavior with increased ethylene production and rate of respiration. The specific activity of amylase increased throughout the growth period of sunberry, but that of invertase decreased after maturity until ripening. The catalase and peroxidase enzymes showed higher activity, indicating better radical scavenger properties, while cellulase, polygalacturonase and pectinmethylesterase tended to remain at lower levels. Conclusion. The fruit of P. minima are nutritive and a rich source of sugars, starch, free amino acids, proteins, total phenols and ascorbic acid. They are metabolically active, showing a high specific activity of hydrolyzing and antioxidant enzymes, while the activity of cell wall-degrading enzymes is relatively low, indicating a better postharvest storage life. India / Physalis minima / fruit / growth / ripening / developmental stages / physicochemical properties Changements physico-chimiques du fruit de Physalis minima L. pendant sa croissance et sa maturation. Résumé-Introduction. L'espèce Physalis minima est largement répandue ; c'est une plante fruitière herbacée annuelle, de la famille des solanacées, à croissance rapide et hauts rendements. Cependant, comme beaucoup d'autres plantes fruitières sous-utilisées, l'espèce P. minima est peu étudiée et les qualités nutritionnelles de son fruit sont peu connues. Puisque le physalis comestible est dit riche en vitamine C, nous avons étudié les modifications physico-chimiques qui interviennent au cours de la croissance et de la maturation de son fruit. Matériel et méthodes. Les changements de caractéristiques physico-chimiques, tels que le pH, les solides solubles totaux, l'acidité titrable, les chlorophylles, les caroténoïdes, les glucides (sucres réducteurs, non réducteurs, sucres totaux et amidon), les acides aminés libres, les protéines totales, les phénols totaux, l'acide ascorbique, l'éthylène et la respiration, l'activité des enzymes hydrolytiques (amylase et invertase), des enzymes antioxydants (catalase et peroxydase) et des enzymes de dégradation des parois cellulaires (cellulase, polygalacturonase et pectinmethylesterase), ont été analysés dans le fruit de P. minima à cinq stades de développement successif : jeune, prémature, mature, prémûr et mûr. Résultats et discussion. Une augmentation progressive du pH et des solides solubles totaux a été observée tout au long de la croissance et de la maturation du fruit, tandis que son acidité titrable augmentait jusqu'au stade prémûr pour ensuite diminuer. Les chlorophylles ont eu tendance à diminuer en même temps qu'augmentait la quantité des caroténoïdes. La quantité totale de l'amidon a nettement diminué avec la maturation du fruit et, de façon concomitante, la quantité des sucres réducteurs, non réducteurs et sucres totaux a augmenté. Une augmentation de la quantité d'acides aminés libres, de protéines, de phénols a eu lieu également au cours de la croissance et de la maturation du fruit de physalis. Par ailleurs, la quantité d'acide ascorbique a aussi augmenté au stade du fruit mûr. En outre, le physalis se comporte comme un fruit climactérique du fait de l'augmentation de sa production d'éthylène et de son taux respiratoire. L'activité spécifique de l'amylase a augmenté tout au long de la période de croissance du fruit, mais celle de l'invertase a diminué après la maturité. Les catalase et peroxydase ont montré une activité accrue, indiquant une meilleure aptitude au piégeage des radicaux libres, tandis que les cellulase, polygalacturonase et pectinmethylesterase ont eu tendance à rester à des niveaux inférieurs. Conclusion. Le fruit de P. minima est nutritif ; il est une riche source en sucres, amidon, acides aminés libres, protéines, phénols totaux et acide ascorbique. Ce fruit est métaboliquement actif ; il présente une activité spécifique élevée des enzymes hydrolysants et antioxydants, tandis que l'activité des enzymes de dégradation de la paroi cellulaire est relativement faible, indiquant une meilleure aptitude à la conservation après récolte.

Fruits, 2011

Physiochemical changes in sunberry (Physalis minima L.) fruit during growth and ripening. Abstract-Introduction. Physalis minima is a widespread, quick-growing and high fruit-yielding annual herb belonging to the family Solanaceae. However, like many other underutilized fruit-bearing plants, P. minima is poorly studied and its nutritional potential is unknown. Since the edible sunberry is said to be a rich source of vitamin C, we studied the physiochemical changes during its fruit growth and ripening. Materials and methods. The changes in the physiochemical properties, such as pH, total soluble solids, titrable acidity, chlorophylls, carotenoids, carbohydrates (reducing sugars, non-reducing sugars, total sugars and starch), free amino acids, total proteins, total phenols, ascorbic acid, ethylene, and respiration and the activities of hydrolytic enzymes (amylase and invertase), antioxidant enzymes (catalase and peroxidase), and cell wall-degrading enzymes (cellulase, polygalacturonase and pectinmethylesterase), were analyzed in the fruit of sunberry at five sequential stages, viz., the young, premature, mature, preripe and ripe stages. Results and discussion. A gradual increase in the pH and total soluble solids occurred throughout the growth and ripening of sunberry fruit, while its titrable acidity increased up to the preripe stage and thereafter declined. A decreasing trend in the chlorophylls occurred simultaneously with an increase in the quantity of carotenoids. As the sunberry fruit proceeded towards ripening, the amount of its total starch decreased, with a concomitant sharp increase in the quantity of its reducing sugars, non-reducing sugars and total sugars. An increase in the quantity of free amino acids, proteins and phenols also occurred during the growth and ripening of the fruit, and the quantity of ascorbic acid increased at the mature stage. Moreover, sunberry fruit also exhibits a climacteric behavior with increased ethylene production and rate of respiration. The specific activity of amylase increased throughout the growth period of sunberry, but that of invertase decreased after maturity until ripening. The catalase and peroxidase enzymes showed higher activity, indicating better radical scavenger properties, while cellulase, polygalacturonase and pectinmethylesterase tended to remain at lower levels. Conclusion. The fruit of P. minima are nutritive and a rich source of sugars, starch, free amino acids, proteins, total phenols and ascorbic acid. They are metabolically active, showing a high specific activity of hydrolyzing and antioxidant enzymes, while the activity of cell wall-degrading enzymes is relatively low, indicating a better postharvest storage life. India / Physalis minima / fruit / growth / ripening / developmental stages / physicochemical properties Changements physico-chimiques du fruit de Physalis minima L. pendant sa croissance et sa maturation. Résumé-Introduction. L'espèce Physalis minima est largement répandue ; c'est une plante fruitière herbacée annuelle, de la famille des solanacées, à croissance rapide et hauts rendements. Cependant, comme beaucoup d'autres plantes fruitières sous-utilisées, l'espèce P. minima est peu étudiée et les qualités nutritionnelles de son fruit sont peu connues. Puisque le physalis comestible est dit riche en vitamine C, nous avons étudié les modifications physico-chimiques qui interviennent au cours de la croissance et de la maturation de son fruit. Matériel et méthodes. Les changements de caractéristiques physico-chimiques, tels que le pH, les solides solubles totaux, l'acidité titrable, les chlorophylles, les caroténoïdes, les glucides (sucres réducteurs, non réducteurs, sucres totaux et amidon), les acides aminés libres, les protéines totales, les phénols totaux, l'acide ascorbique, l'éthylène et la respiration, l'activité des enzymes hydrolytiques (amylase et invertase), des enzymes antioxydants (catalase et peroxydase) et des enzymes de dégradation des parois cellulaires (cellulase, polygalacturonase et pectinmethylesterase), ont été analysés dans le fruit de P. minima à cinq stades de développement successif : jeune, prémature, mature, prémûr et mûr. Résultats et discussion. Une augmentation progressive du pH et des solides solubles totaux a été observée tout au long de la croissance et de la maturation du fruit, tandis que son acidité titrable augmentait jusqu'au stade prémûr pour ensuite diminuer. Les chlorophylles ont eu tendance à diminuer en même temps qu'augmentait la quantité des caroténoïdes. La quantité totale de l'amidon a nettement diminué avec la maturation du fruit et, de façon concomitante, la quantité des sucres réducteurs, non réducteurs et sucres totaux a augmenté. Une augmentation de la quantité d'acides aminés libres, de protéines, de phénols a eu lieu également au cours de la croissance et de la maturation du fruit de physalis. Par ailleurs, la quantité d'acide ascorbique a aussi augmenté au stade du fruit mûr. En outre, le physalis se comporte comme un fruit climactérique du fait de l'augmentation de sa production d'éthylène et de son taux respiratoire. L'activité spécifique de l'amylase a augmenté tout au long de la période de croissance du fruit, mais celle de l'invertase a diminué après la maturité. Les catalase et peroxydase ont montré une activité accrue, indiquant une meilleure aptitude au piégeage des radicaux libres, tandis que les cellulase, polygalacturonase et pectinmethylesterase ont eu tendance à rester à des niveaux inférieurs. Conclusion. Le fruit de P. minima est nutritif ; il est une riche source en sucres, amidon, acides aminés libres, protéines, phénols totaux et acide ascorbique. Ce fruit est métaboliquement actif ; il présente une activité spécifique élevée des enzymes hydrolysants et antioxydants, tandis que l'activité des enzymes de dégradation de la paroi cellulaire est relativement faible, indiquant une meilleure aptitude à la conservation après récolte.

Phytochemistry, 2013

Abscisic acid (ABA) 9-Cis-epoxycarotenoid dioxygenase (NCED) Neoxanthin synthase (NSY) Aldehyde oxidase (AO) a b s t r a c t Abscisic acid (ABA) is a natural plant hormone playing an important role in many physiological processes including fruit ripening and is also recently found to be potential for biomedical applications. This study was aimed to measure ABA levels and its biosynthesis in bilberry (Vaccinium myrtillus L.), which is one of the best sources of anthocyanins. Five ABA biosynthetic genes were isolated from bilberry and their expression profiles were studied in bilberry tissues, particularly during berry development. The level of ABA highly increased at the onset of bilberry fruit ripening, at the stage when expression of anthocyanin biosynthetic genes, chalcone synthase (VmCHS) and anthocyanidin synthase (VmANS), also increased. In fully ripe berries and leaves, ABA levels were lower but none was detected in bilberry stem or rhizome. The expression of 9-cis-epoxycarotenoid dioxygenase (VmNCED1) and putative neoxanthin synthase (VmNSY) was high in berry tissues and their expression increased markedly at the onset of berry ripening along with the accumulation of ABA. In contrast, the expression of zeaxanthin epoxidase (VmZEP), short-chain dehydrogenase/reductase (VmSDR/ABA2) and aldehyde oxidase (VmAO) were most highly associated with leaf tissues with no obvious relation to ABA content during berry development. The obtained results indicate that the ABA biosynthesis may play an important role in the regulation of ripening of non-climacteric bilberry fruits through transcriptional regulation of key ABA biosynthetic genes.

The Horticulture Journal, 2022

Changes in anthocyanin and endogenous abscisic acid (ABA) contents in the berry skins of Vitis labruscana × V. vinifera cultivars, 'Aki Queen', and 'Ruby Roman' were investigated during the fruit development period. Color development of 'Aki Queen' berries mainly occurred within 20 days post véraison, while that of the 'Ruby Roman' was prolonged for about 40 days. In both cultivars, the ABA level in the berry skin started to increase a few days before véraison; however, ABA accumulation ceased approximately 10 days after véraison in 'Aki Queen', while it continued until the late stage of maturation in 'Ruby Roman'. In addition, higher indole-3-acetate aspartate (IAA-Asp) and lower isopentenyladenine (iP) contents were observed in 'Ruby Roman' than in 'Aki Queen' at the late development stage. The expression analysis of genes involved in ABA metabolism revealed that V. vinifera 9-cis-epoxycarotenoid dioxygenase 3 (VviNCED3), which is assumed to play a major role in ABA biosynthesis, remained relatively higher in 'Ruby Roman' than in 'Aki Queen' after véraison. Considering that ABA plays a regulatory role in grape maturation, these results may indicate that the coloration of 'Ruby Roman' at the later stage of maturation is partly attributable to an increased ABA pool in berry skins.

Horticulturae

Fresh blueberries are prone to softening and dehydration during postharvest, which limits their competitiveness when reaching the final markets. Commercial cultivars ‘Duke’ and ‘Brigitta’ exhibit contrasting softening patterns. Although ‘Duke’ berries usually show higher firmness levels at harvest as compared to ‘Brigitta’, they display higher softening and weight loss rates after cold storage. The aim of this study was to evaluate the physicochemical changes and modifications in cuticle composition of ‘Duke’ and ‘Brigitta’ blueberries across five developmental stages: green (G), 25 and 50% pink (25P, 50P), and 75 and 100% blue (75B, 100B), to determine those characters with the most influence on their postharvest behavior. For each developmental stage, maturity parameters, respiration, and ethylene production rates were assessed, and cuticular wax and cutin were analyzed. Principal component analysis (PCA) revealed that ‘Duke’ berries were characterized by higher respiration and et...

The Horticulture Journal

This study investigated anthocyanin accumulation, sugar contents, and endogenous hormone contents in the berry skin, as well as the expression of genes related to anthocyanin and abscisic acid (ABA) synthesis and metabolism, using grafted 'Ruby Roman' berries on the rootstocks of 'Kober 5BB' [5BB(2x), a semidwarf rootstock], 'Hybrid Franc' [HF(2x), a vigorous rootstock], and their colchicine-induced autotetraploids [5BB(4x) and HF(4x)]. Rootstock had significant effects on the total content, but not on the composition, of anthocyanins. The berries on 5BB(4x) rootstock, where the grapevine showed less vegetative growth, had higher anthocyanin content during the ripening process, and also had higher sugar and ABA contents around véraison. ABA, indole acetic acid (IAA), and cytokinins showed synchronous changes during berry development: they had the lowest levels at pre-véraison, and their metabolic pathways were accelerated after véraison. Furthermore, they all tended to be higher on 5BB(4x) than on the other rootstocks. Since the expression levels of most of the ABA biosynthesis-related genes did not show a corresponding increase with the contents of ABA and ABA-glucosyl ester (ABA-GE), it is considered that the increase in ABA content after véraison may be mainly due to the decrease in catabolism and/or exogenous import from other organs. This study provides an overview showing the dynamic changes and relationship of three phytohormones during the ripening of grape berries grafted on different rootstocks, and explores the mechanisms regulating ripening.

Frontiers in Plant Science

Blueberry (Vaccinium corymbosum L.) is a widely consumed fruit and a rich source of bioactive compounds, namely, the polyphenol class of anthocyanins. Little information is available about the influence of internal (genetic and developmental) and external (environmental) factors on the levels of phenolic metabolites in blueberry fruit. In light of this consideration, total polyphenolic and flavonoid content, anthocyanin accumulation and composition were evaluated in cv. "Duke" and "Brigitta" grown at two different altitudes in Valtellina, a valley of the Alps in Northern Italy. During berry ripening, there is a developmentally coordinated shift from cyanidin-type, di-substituted anthocyanins toward delphinidinbased, tri-substituted pigments. At the lower altitude location, higher temperatures, not exceeding optimum, resulted in a more quickly berry developmental pattern and in higher anthocyanin concentrations in the early phases of ripening. At later stages of ripening, berries of both cultivars at higher altitude compensate for these initial temperature effects, and no differences were recorded in ripe fruit grown in the two locations. We conclude that anthocyanin accumulation is strongly regulated by development and genotype, and the environmental factors, associated to the altitude gradient, exert in the trial conditions only a fine-tuning influence. Fruits reach the full-ripening stage simultaneously at both sites because the initial gap in pigment levels is counterbalanced at the higher altitude by a faster rate of accumulation at later phases of the ripening process.

Fruit color and aroma volatile compounds are important factors that determine fruit quality. The effects of jasmonates (jasmonic acid and methyl jasmonate) on fruit color development differed between climacteric and nonclimacteric fruit. Jasmonates, and jasmonates combined with an ethylene action inhibitor stimulated greater anthocyanin accumulation in apples regardless of fruit growth stages. The expression of UDP-glucose:flavonoid 3-O-glucosyltransferase (UFGluT) anthocyanin biosynthetic gene was increased in the skin of fruits treated with jasmonates and these fruits also had much higher anthocyanin content than untreated controls. In contrast, jasmonates did not influence anthocyanin accumulation in sweet cherries. The impact of jasmonate application on volatile compound production was dependent on fruit ripening stage; jasmonates increased the volatiles in preclimacteric fruit, but decreased the volatiles in climacteric fruit. In addition, jasmonates influenced 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS) and ACC oxidase (ACO) gene transcription. In pears (Pyrus communis L.), jasmonate application at the preclimacteric stage stimulated ethylene production and the expression of the ACS and the ACO messenger RNA (mRNA) levels. In contrast, the accumulation of ACS mRNA levels in fruit treated with jasmonate at the climacteric stage was low and ethylene production also decreased. Some types of physiologically active substances may play a protective role against chilling injury. For example, endogenous polyamines were linked to the degree of chilling injury in mangosteens. Additionally, EC 50 values of superoxide (O 2-) and 1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity were also associated with the degree of chilling injury.