Purpose: Apple fruit widely suffers from different damages every year including post-harvest diseases such as blue mold (caused by Penicillium expansum). Recent studies have shown the role of ...hormones in different signaling pathways after a pathogen attack. Hormones may trigger different the expression of genes involved in the resistance mechanism and thus activating the immune system in plants. Findings: qRT-PCR results showed an increase in the expression of PR5, ERF1 and CHIB genes after treatment with BABA in both Golden Delicious and Fuji cultivars. ACC treatment also significantly increased the expression of ERF1 and CHIB genes after challenged with fungal spores. The expression of PR5 and ERF1 was relatively very similar in both cultivars after treatment with BABA and ACC, respectively. In contrast, the expression of CHIB was different in two cultivars, thus showing a 4 times higher expression in Golden delicious in compared to Fuji. Originality/Value: Using of new insecticides with new and widespread mode of action can be recommended against postharvest pest in the practical entomology. Research limitations: No limitations were found. Originality/value: The results of this study can be important in breeding studies and to select genes involved in the resistance mechanism. In addition, hormones with a positive impact to provide resistance to fungal diseases can be considered as a possible alternative to fungicides.
•A large global dataset from 14 sites and for early and late flowering was used to investigate flowering phenology models.•The chill overlap model was found to perform better than the sequential ...model for all analyses.•Mild northern and southern hemisphere sites were least well represented highlighting a deficiency in model design.
This study presents the first evaluation of apple flowering phenology models using data from 14 sites across the globe. The dataset includes large variability in growing climates, a prerequisite to investigate phenology models for use in climate change applications. Two flowering stages, early and full, were investigated allowing for unique model evaluation based on both statistical performance and biological assumptions. Two overarching phenology models (Sequential and Chill Overlap) and two sub-models of chill (Dynamic and Triangular) and heat (GDH and Sigmoidal) were tested. Flowering times from the different sites illustrated the differing effects of contrasting winter and spring temperatures. Sites with similar springtime temperatures, but different winter temperatures, had different flowering patterns (warmer winter sites flowered later). Across all analyses, results from the Chill Overlap model were better than those from the Sequential model. Of the Chill Overlap models, those fitted with the Triangular or Dynamic chill model and the GDH heat sub-model performed well statistically and met the assumptions of the model across both flowering stages. The mild sites in the analysis were least well represented, regardless of model selection. This global evaluation demonstrated that flowering modelling in temperate fruit trees would progress through appropriate choices of overarching model, sub-models and parameters.
•Study of the Effect of CaCl2 and 1-MCP and their combination on apple storage.•Development of physiological disorders of ‘Golden Delicious’ apples in storage.•1-MCP prevents superficial scald but ...increases bitter pit severity.•CaCl2 dip prior to 1-MCP treatment prevents reduces the bitter pit.
Calcium (Ca2+) and 1-methylcyclopropene (1-MCP) appear to have opposite effects on the development of bitter pit. However, both post-harvest treatments seem capable of influencing fruit ripening, reducing superficial scald and improving post-storage quality. The objective of this work was to investigate the effect of calcium chloride and 1-MCP alone or combined on the incidence and development of physiological disorders and the delay of ripening of apples during storage (at 0.5°C in air) and subsequent shelf-life at room temperature ≈22°C. ‘Golden Delicious’ apples were harvested in 10 orchards and treated with calcium chloride (1.5%, w/v), 1-MCP (625nLL−1), calcium chloride plus 1-MCP, and without any treatment (control). Physiological disorders and quality parameters were evaluated at harvest and after 6 months storage as well as after 7 d shelf-life. The 1-MCP treatment was effective to prevent superficial scald, slow softening, increase soluble solids content and reduce electrolyte leakage and color changes associated with ripening, during storage and shelf-life. However, this treatment also enhanced the development of bitter pit, especially the moderate and severe symptoms in some orchards, which may be attributable to orchard cultivation techniques. CaCl2 alone and CaCl2 plus 1-MCP reduced bitter pit intensity by reducing moderate and severe incidence, maintained higher lightness and had firmer fruit than control.
Postharvest dips of ‘Golden Delicious’ apples in CaCl2 before 1-MCP application (CA+MCP), may be a good solution to prevent scald, and reducing the bitter pit which is enhanced by 1-MCP alone.
The apple greasiness disorder can seriously affect the quality of appearance and commercial value. However, the complex molecular mechanism of fatty acid desaturases (FADs) in greasiness disorder has ...not been explored. In this study, greasiness disorder of susceptible cultivar 'Golden Delicious' apples could be characterized by comprehensive evaluation system: At the physiological level, the disorder was associated with high level of the greasiness score, the respiration rate, ethylene release and the MDA content; At the morphological level, it caused the epidermal wax crystals disappeared with the appearance of a liquid wax form of the pericarp; At the metabolic level, it increased the liquid greasiness components and contents. As the MdFADs, induced by the greasiness esters, were key genes in the greasiness disorder process, and MdFAD27 and MdFAD28 were obtained by analyzing their family members at transcriptomic level during postharvest storage. Furthermore, the results from both homologous overexpression in apples and heterologous overexpression in tomatoes indicated that MdFAD27 and MdFAD28 were involved in the formation of the main substrate of greasiness esters and the phenotype of greasiness disorder. Collectively, this study shows that MdFAD27 and MdFAD28 influence the development of greasiness disorder in apples by promoting the production of greasiness components.
•Greasiness disorder of apple can be determined by a comprehensive evaluation system.•linoleic acid and oleic acid provided key substrates for the greasiness.•MdFAD27/28 may be key members involved in the occurrence of greasiness.
The experiment was conducted on apple trees cv. Golden Delicious,12 years old planted at a distance of 4 × 4 m in a private orchards in Bagerat village (25 km northeast of the city of Dohuk), during ...the growing season 2012,to study the effect of Matrix 15 and ascorbic acid on yield and some chemical fruit parameters. Three levels of Matrix15 (15% humic acid) (0, 10 and 20 ml /L./ trees) were applied in two installments during the season (1/2L to Trevi each batch), the first after flowering (mid of April 15/4). The second after one month, and the trees were sprayed until wetness with three levels of of ascorbic acid (0, 150 , 300 mg /L.) and three times during the season of the study. All the spraying and sprinkles and addition were done early of the morning. Result showed that application of Matrix15 fertilizer (15% humic acid) significantly affected the fruit set , number of fruits at harvest ,yield of each tree, percentage of total acidity ,total sugars and ascorbic acid in fruit juice. Olso the spraying of ascorbic acid especially the concentration 150 mg /L. significantly increased the number of fruits at harvest ,yield of each tree mean while the foliar spray of 300 mg/L. significantly increased the percentage of total sugars in fruit juice. The interaction between the factors significantly affected on all studied parameters except fruit volume and TSS.
The effect of heat treatment on fruit firmness and related enzymes, acidity and related enzymes, and energy metabolism on postharvest apple fruit was investigated. Results showed that heat treatment ...prevented softening at the early stage and maintained acidity. Compared with the control, heat treatment markedly inhibited the transcript level of MdcyME1–3 but improved the transcript level of MdPG3 and MdGAL1, thus heat‐treated fruit exhibited higher activity of polygalacturonase (PG) and β‐galactosidase (β‐Gal). Moreover, levels of energy charge in heat‐treated fruit were significantly higher than that in the control fruit. These results suggested that β‐Gal played an important role in apple fruit softening at the later storage, and heat treatment maintained acidity and energy metabolism while enhanced the activity of cell wall enzymes.
Practical applications
To reveal the mechanism of energy metabolism affecting fruit softening and change in fruit acidity, the enzyme activity and gene expression of apple fruits after heat treatment were studied. By comparing the heat treatment group with the control group, this study successfully explained the genomic mechanism controlling apple fruit acidity and softening in the fruit mature period at high level of energy charge, found key cell wall enzymes and candidate genes, and supplied theoretical guidance for maintaining the fruit quality of “Golden Delicious” fruit.
Heat treatment markedly inhibited the transcript level of MdcyME1–3 but improved the transcript level of MdPG3 and MdGAL1.
Heat treatment maintained acidity and energy metabolism while enhanced the activity of cell wall enzymes.
β‐Gal played an important role in apple fruit softening at the later storage.
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•The process of abscission of apple flowers was monitored.•Focus was on differences among central and lateral fruitlets along peduncle.•The abscission did not differ among lateral ...fruitlets in 4- or 5-flowered clusters.•In 6-flowered clusters greater abscission was at position nearest to the king fruit.•The competition was reflected in quality parameters of lateral fruit at harvest.
Apple trees (Malus domestica Borkh.) develop an abundance of flowers and shed the majority of fruitlets in the first developmental stages. In this study the process of abscission was monitored in cultivar ‘Golden Delicious’ and linked with the position of fruitlets in the cluster, focusing on differences among central or king flower/fruit (K1), flowers/fruit nearest to the king flower (lower on the peduncle; L2) and flowers/fruit located at different positions near the base of the peduncle (L3-L6). Individual clusters consisted of 3–7 flowers the most frequent were clusters with 5 flowers. Abscission was biphasic with the first peak 29 days after full bloom (DAFB) and the second peak 48 DAFB. At the end of the abscission process approx. 70% of all fruitlets shredded. Fruitlets at the central position (K1) were frequently unaffected by this process and developed to fruit in 70% of the analyzed clusters. The ratio between subsisting and shedded fruitlets was the opposite for lateral positions in the cluster; approx. 70% of fruitlets abscised in the clusters with 4/5 flowers. No significant differences in the level of abscission have been observed between the lateral positions in the cluster (L2-L6). A tendency to abscission has been detected for L2 position (lateral fruitlet nearest to the king flower) in clusters consisting of 6 flowers. This was further confirmed at harvest. Fruit from the lateral position nearest K1 were smaller and firmer in comparison to K1, L3 and L4. This demonstrates the obvious dominance of the central fruit in comparison to lateral fruit, especially those nearest to the king fruit. This is particularly evident in clusters with many flowers.
Maturity at harvest is one of the most important properties that determine the final quality of the apple fruit. Appearance, texture, flavour and nutritional value are qualities that consumers ...evaluate empirically to decide whether to eat the fruit again. Within agricultural practices in and out of the orchard, the relationship between plant nutrition and fruit quality is important, and proper nutrient balance is essential to maintain fruit quality. This research work was carried out on ‘Golden Delicious’ and ‘Red Chief’ apple trees. A 56 factorial arrangement was used, with 5 concentrations and 6 factors, 25 treatments in a Taguchi L25 structure. Improvements were found in parameters for fruit finish and fruit quality. The factors with the greatest positive effect on quality in order of importance were Salicylic Acid (SA) 1.0 mM, Potassium (K) 58.90 mM, Molybdenum (Mo) 0.516 mM, Calcium (Ca) 70.00 mM and Cobalt (Co) 8.248 mM and in order of importance the following variables: TSS/acidity ratio, total soluble solids TSS, antioxidant capacity (AC), total phenols (TF), and titratable acidity (TA) in ‘Golden Delicious’ apple. Considering ‘Red Chief’, the factors Ca 70.00 mM, K 58.79 mM and SA 1.0 mM, with the variables; TA, TSS/acidity ratio, TF, TSS and AC that finally lead to an optimal development of finish and quality in the apple fruit.
Triterpenoids are a group of secondary plant metabolites, with a remarkable pharmacological potential, occurring in the cuticular waxes of the aerial parts of plants. The aim of this study was to ...analyze triterpenoid variability in the fruits and leaves of three apple cultivars during the growing season and gain new insights into their health-promoting properties and fate during juice and purée production. The identification and quantification of the compounds of interest were conducted using gas chromatography coupled with mass spectrometry. The waxes of both matrices contained similar analytes; however, their quantitative patterns varied: triterpenic acids prevailed in the fruits, while higher contents of steroids and esterified forms were observed in the leaves. The total triterpenoid content per unit area was stable during the growing season; the percentage of esters increased in the later phases of growth. Antioxidative and anti-inflammatory properties were evaluated with a series of in vitro assays. Triterpenoids were found to be the main anti-inflammatory compounds in the apples, while their impact on antioxidant capacity was minor. The apples were processed on a lab scale to obtain juices and purées. The apple purée and cloudy juice contained only some of the triterpenoids present in the raw fruit, while the clear juices were virtually free of those lipophilic compounds.
The main aim of the study was to prepare the edible films based on carrageenan/chitosan and incorporate them into the following matrices: the natural extracts of Clitoria ternatea, Brassica oleracea, ...and Ipomea batatas. The films were characterized by TPC (total polyphenols content), antioxidant activity, and textural properties. Experimentally produced films were added in the packaging of freshly cut apple pieces, and the apple pieces were dipped into the films produced from carrageenan and chitosan. The appearance of the samples was monitored, as were antioxidant activity and total polyphenol content. The intelligent properties of films were evaluated too. The polymer type used for the preparation had the highest impact on the prepared films, and CHLCZ (red cabbage extract—Brassica oleracea) featured the best antioxidant activity. The intelligent properties were slightly confirmed in samples with the addition of red cabbage. The main finding was that the coating of fresh-cut apples emphasized the possibility to use a carrageenan matrix with the addition of extracts. The samples immersed in this coating type showed higher antioxidant activity as well as a superior color when compared to that of chitosan coated apple samples.
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