Red Jonaprince Research Articles

Assessing Antioxidant Properties, Phenolic Compound Profiles, Organic Acids, and Sugars in Conventional Apple Cultivars (Malus domestica): A Chemometric Approach.

This study analyzed the phenolic compounds, organic acids, sugars, and antioxidant activity in different conventional apple cultivars (Malus domestica) from the Serbian market. Polyphenol profiles, sugars, and organic acid contents were analyzed by HPLC, and antioxidant activity was examined by DPPH and FRAP. Notable findings included variations in phenolic compound presence, with certain compounds detected only in specific cultivars. 'Red Jonaprince' exhibited the highest arbutin (0.86 mg/kg FW) and quercetin-3-rhamnoside content (22.90 mg/kg FW), while 'Idared' stood out for its gallic acid content (0.22 mg/kg FW) and 'Granny Smith' for its catechin levels (21.19 mg/kg FW). Additionally, malic acid dominated among organic acids, with 'Granny Smith' showing the highest content (6958.48 mg/kg FW). Fructose was the predominant sugar across all cultivars. Chemometric analysis revealed distinct groupings based on phenolic and organic acid profiles, with 'Granny Smith' and 'Golden Delicious' exhibiting unique characteristics. Artificial neural network modeling effectively predicted antioxidant activity based on the input parameters. Global sensitivity analysis highlighted the significant influence of certain phenolic compounds and organic acids on antioxidant activity.

Impact of selenium fertilisation of ‘Red Jonaprince’ apple trees on selenium nutrition and fruit quality and storability

Selenium (Se) malnutrition in humans is caused by low soil Se availability, leading to an insufficient content of this nutrient in food. In this study, we examined the effect of Se fertilisation on the absorption and distribution of Se in apple (Malus domestica Borkh.) trees, as well as fruit quality and storability. The experiment was carried out on mature ‘Red Jonaprince’ apple trees grown in medium-textured soil. Fertilisation of Se (as sodium selenate) was applied as: (i) summer sprays, 4 times in a season at a rate of 50 g Se ha−1, (ii) a fall spray, 2 weeks before harvest at a rate of 200 g Se ha−1, (iii) soil application at a rate of 500 g Se ha−1, and (iv) fertigation at a rate of 100 g Se ha−1. Trees that were not fertilised with Se served as controls. The results revealed that the fall Se spray caused leaf burns and defoliation, but it did not affect tree vigour and fruit yield. The highest leaf Se concentration was found on Se-sprayed trees in the fall. Most Se in fruit was recorded on Se-sprayed trees in the fall and on Se-fertigated trees; fruit Se amounts from these combinations covered about 30 % of the recommended daily intake. None of the Se treatments affected fruit appearance (mean weight, skin russeting, and colour), flesh firmness, and acidity at harvest. Apart from the fall Se spray, the other treatments decreased the soluble solid concentration (SSC), starch index values, ethylene evolution, and increased Streif index values in apples at harvest. After storage, Se-enriched apples were firmer, contained more organic acids, and produced less ethylene than the control fruit. We conclude that Se fertigation or a fall Se spray can be recommended in apple orchards, at least for late season and winter varieties, to biofortify fruit with Se and delay their ripening process.

Assessment of the Quality of ‘Red Jonaprince’ Apples during Storage after Delayed Harvesting and 1-Methylcyclopropene (1-MCP) Preharvest and Postharvest Treatment

Changing the harvesting time of apples from the optimum harvest window to delayed harvesting may be applied if it is impossible to harvest apples at the optimal time, but it requires changing other factors, as they influence the quality of fruits and shelf life. The aim of the study was to assess the quality of ‘Red Jonaprince’ apples during storage after delayed harvesting and 1-methylcyclopropene (1-MCP) preharvest and postharvest treatment for various storage times. Apples were studied within four groups subjected to preharvest and postharvest treatments, as follows: Group 0—no 1-MCP treatment; Group 1—1-MCP preharvest treatment; Group 2—1-MCP postharvest treatment; and Group 3—1-MCP preharvest and postharvest treatment. All apples were subjected to ultra-low oxygen (ULO) storage conducted for 3, 5 or 6 months, while the analyses were conducted directly after ULO storage (simulated shelf life—0 days) and after simulated shelf life (7 days). For firmness, in the case of 1-MCP applied only preharvest (Group 1) and only postharvest (Group 2), before shelf life, the longer ULO storage resulted in obtaining lower values of firmness (p < 0.0001). If 1-MCP was not applied postharvest (Group 0 and Group 1), and short ULO storage was applied (3 and 5 months for Group 0; 3 months for Group 1), after shelf-life lower values of firmness were observed (p < 0.0001). For soluble solids content (SSC), in the case of 1-MCP not applied preharvest (Group 0 and Group 2), before shelf life, and for 1-MCP applied postharvest (Group 2) after shelf life, the longer ULO storage resulted in obtaining lower values of SCC (p < 0.0001). For titratable acidity (TA), in the case of all the studied groups after shelf life, as well as in case of 1-MCP applied only preharvest (Group 1) also before shelf life, the longer ULO storage resulted in obtaining lower values of TA (p < 0.0001). Except for the 1-MCP applied only postharvest (Group 2), in the case of short ULO storage applied (3 and 5 months for Group 0; 5 months for Group 1; 5 months for Group 3), after shelf-life lower values of TA were observed (p < 0.0001). If delayed harvesting must be conducted, applying 1-MCP not only postharvest, but also preharvest, allows obtaining the most stable firmness and SSC, which do not decrease during storage and shelf life. Taking this into account, it may be concluded, that in the case of delayed harvesting, combining 1-MCP applied preharvest and postharvest should be recommended to keep the quality parameters stable during storage and shelf life.

The Effect of Increasing Irrigation Rates on the Carbon Isotope Discrimination of Apple Leaves

13C discrimination (Δ13C) has been used in research as an indicator of water availability in crops; however, few data are available concerning fruit trees. The aim of this study was to examine the effect of irrigation on the Δ13C values of apple leaves. We assumed that Δ13C would increase with irrigation intensity. The Δ13C of apple trees (Malus domestica) cv. ‘Red Jonaprince’ was determined in the years 2019–2022. Leaf samples were collected in spring, in June, at the beginning of the irrigation campaign, and in autumn, in September, following the harvest. The irrigation doses were applied to replenish the water consumption, 0% (ET0), 50% (ET50), 75% (ET75), and 100% (ET100), of the calculated evapotranspiration (ET) levels. In November, the leaves collected from different positions on the shoots were sampled, assuming the Δ13C signature would reflect the changes occurring in the water supply during their growth. The irrigation rates had a significant effect on the Δ13C of the leaves when the data for the spring and summer months were pooled. On average, Δ13C increased from 20.77‰ and 20.73‰ for ET0 and ET50, respectively, to 20.80‰ and 20.95‰ for ET75 and ET100, respectively. When the data obtained for the spring and summer months were analysed separately, the effect of irrigation was weak (p < 0.043). The Δ13C value was always higher for treatment ET100 than treatment ET0, for individual experimental years and terms; however, the differences were minor and mostly insignificant. The leaf position had a strong significant effect on Δ13C; the values gradually decreased from the leaves growing from two-years-old branches (22.50‰) to the youngest leaves growing at the top of the current year’s shoots (21.07‰). This order was similar for all the experimental years. The results of the experiment suggest that 13C discrimination in apples is affected not only by water availability during growth, but also by the use of C absorbed in previous years.

Tree Root-Associated Microbial Communities Depend on Various Floor Management Systems in an Intensive Apple (Malus × domestica Borkh.) Orchard.

Regenerative 3agriculture prioritizes soil health to build up organic soil carbon and nitrogen stocks while supporting the active and diverse soil biota that is a prerequisite for maintaining crop productivity and quality in sustainable food production. This study aimed at unravelling the impact of organic and inorganic soil maintenance systems in a 'Red Jonaprince' apple (Malus × domestica Borkh.) orchard on soil microbiota biodiversity and soil physico-chemical properties. During our study, we compared seven floor management systems in terms of microbial community diversity. Fungal and bacterial communities on all taxonomic levels differed largely between systems that augmented organic matter (organic) and other tested inorganic regimes. The dominant phylum of the soil in all management systems was Ascomycota. The operational taxonomic units (OTUs) within the Ascomycota were largely identified as members of Sordariomycetes, followed by Agaricomycetes, and both dominated in organic systems versus inorganic. The most prominent phyla, Proteobacteria, accounted for 43% of all assigned bacteria OTUs. Gammaproteobacteria, Bacteroidia, and Alphaproteobacteria were predominant in organic samples, while Acidobacteriae, Verrucomicrobiae, and Gemmatimonadetes were more abundant in inorganic mulches.

The Effect of Drip Irrigation on the Length and Distribution of Apple Tree Roots

In a three-year experiment (2019–2021), the roots of 7-year-old apple trees (Malus domestica cv. ‘Red Jonaprince’) grown under drip irrigation were studied. The aim of the study was to determine the effect of irrigation on root density at different depths and distances from the trunk. The working hypothesis assumed that irrigation significantly affects the total length of apple roots. The irrigation treatments corresponding to the calculated water evapotranspiration (ET100), 50% of the calculated ET (ET50), a control (ET0, no irrigation, under rainfed conditions), and a treatment using double-drip lines (2Drops) were monitored. Soil cores were collected in spring and autumn. The total length of the roots (TRLt) and the length of new vital roots (TRLv) to a depth of 80 cm were evaluated. The effects of treatments were mostly insignificant for the TRLt; only in the dry season in 2019 were the TRLt values of the irrigated treatments (ET50 and ET100) significantly higher, 18.67 km·m−2 and 17.45 km·m−2, in comparison to 11.16 km·m−2 for the ET0, at a 10 cm distance from the tree trunk. The irrigation treatments had a statistically significant effect on the TRLv values near the trunk in 2019 and 2020, while in autumn 2020 and 2021, irrigation significantly affected the TRLv at greater distances from the tree trunk. In summary, the irrigation treatments mostly had no significant effect on the total root length. However, an effect of irrigation on the root length of new vital roots was observed at certain sampling dates and distances from the trunk.

Effects of preharvest sprays of iodine, selenium and calcium on apple biofortification and their quality and storability.

The low dietary intake of iodine (I) and selenium (Se) by humans leads to serious health and socioeconomic problems. Therefore, enrichment of plants with I and Se using fertilisers containing these micronutrients is commonly recommended. In this study, we examined the impacts of combined spraying of I as iodide or iodate, Se as selenite or selenate, and calcium (Ca) as Ca-chloride on the enrichment of 'Red Jonaprince' (Malus domestica Borth.) apples, as well as fruit quality and their storability. Sprays were applied 2 weeks before harvest at rates of 0.5 kg I, 0.25 kg Se and 7 kg Ca per ha. Trees not sprayed with these nutrients served as controls. The tested sprays caused leaf burn, but they did not affect the cold injury of buds and shoots. Those sprays had no effect on yield, fruit size and russeting or skin colouring. At harvest, sprayed apples contained about 50 times more I and Se and 30% more Ca than the control fruit. After storage, compared to the control fruit, sprayed apples were firmer, had more organic acids and were less susceptible to disorders, such as bitter pit, internal breakdown and decay caused by Neofabraea spp. The results indicate that preharvest spraying with I, Se and Ca at high rates can be recommended to effectively enrich apples with I and Se and to simultaneously improve their storability.

Effect of microorganisms on degradation of fluopyram and tebuconazole in laboratory and field studies

Nowadays, chemical pesticides are the most widespread measure used to control crop pests and diseases. However, their negative side effects prompted the researchers to search for alternative options that were safer for the environment and people. Pesticide biodegradation by microorganisms seems to be the most reasonable alternative. The aim of the laboratory studies was to assess the influence of Bacillus subtilis and Trichoderma harzianum, used separately and combined together, on fluopyram and tebuconazole degradation. In field studies, the degradation of fluopyram and tebuconazole after the application of the biological preparation in apples was investigated. The results from the laboratory studies show that the greatest decomposition of fluopyram and tebuconazole was observed in tests with T. harzianum in a range of 74.3–81.5% and 44.5–49.2%, respectively. The effectiveness of fluopyram degradation by B. subtilis was 7.5%, while tebuconazole inhibited bacterial cell growth and no degradation was observed. The mixture of microorganisms affected the degradation of fluopyram in a range of 8.3–24.1% and tebuconazole in a range of 6.1–23.3%. The results from the field studies show that degradation increased from 3.1 to 30.8% for fluopyram and from 0.4 to 14.3% for tebuconazole when compared to control samples. The first-order kinetics models were used to simulate the residue dissipation in apples. For the determination of pesticide residues, the QuEChERS method for apple sample preparation was performed, followed by GC–MS/MS technique. Immediately after the treatments, the maximum residue level (MRL) values for tebuconazole were exceeded, and it was equal to 100.7% MRL for the Red Jonaprince variety and 132.3% MRL for the Gala variety. Thus, preharvest time is recommended to obtain apples in which the concentration of pesticides is below the MRL and which can be recognized as safe for humans.

Different Floor Management Systems Affect Soil Properties and Initial Development of Apple Tree (Malus × domestica Borkh.) in an Orchard

In order to achieve sustainable food production, non-chemical weed management practices need to be developed for fruit growing. Tailor-made floor management systems enable efficient weed regulation, but they also affect the soil quality in an orchard. In this article, the effects of various floor management systems in a ‘Red Jonaprince’ apple (Malus × domestica Borkh.) orchard on the soil properties and the trees’ nutritional status and initial development during the first two years after the orchard’s establishment were assessed. The experiment was set up in the spring of 2017 in the Experimental Orchard of WULS. ‘Red Jonaprince’ cv. trees grafted on M.9 rootstock were planted with 3.5 × 1 m spacing between them. Different floor management systems were applied to the rows, including the selected organic mulches: Miscanthus × giganteus straw (MG1 and MG2), spent mushroom substrates (SMS1 and SMS2), herbicide strip (HS), clear mechanical soil cultivation (MC), and synthetic black mulch (BC). The organic mulches affected the soil properties significantly. Spent mushroom substrates (SMS1, SMS2) increased the P and K contents in the soil, increased the salinity 10-fold, and retarded the growth in terms of the trunk cross-section area (TCSA) and its increment compared with other systems. Miscanthus × giganteus straw mulch (MG1, MG2) was associated with a more vigorous shoot growth compared with other combinations in the first year of the study as it provided a better tree nitrogen nutritional status. The floor management system affected the generative development of the trees. Mulching with a spent mushroom substrate boosted the flower bud formation intensity, but it did not affect the yielding quantity. Moreover, due to the poor fruit set, the trees mulched with a spent mushroom substrate (SMS2) gave a low initial bearing. High crop loads were noted for the trees treated with black synthetic mulch (BC) and the trees mulched with Miscanthus × giganteus straw (MG1). This was an effect of the tree size rather than the blooming intensity, while there were no differences in the cropping efficiency index (CEI) parameter.

Response of Apple Flesh to Compression under the Quasi-Static and Impact Loading Conditions.

Compression tests of cylindrical samples were carried out using two 'Rubin' and 'Red Jonaprince' apple cultivars with flesh firmness differing in a statistically significant way. The tests were conducted under both the quasi-static and impact loading conditions, which required the use of two test stands. For this purpose, an impact measuring stand was designed and built. The tests proved that the firmness of the apple flesh influenced the mechanical response under both the quasi-static and impact loading conditions. The elasticity modulus had much higher values under the impact than quasi-static loading conditions. This indicates that the stiffness of the apple tissue was larger during the impact than at the low-speed compression. Different failure mechanisms of cylindrical apple flesh samples were found depending on the loading conditions. Under the quasi-static loading conditions, the apples of both cultivars were damaged at the same strain value. However, during the impact, apples were apt to damage at a constant stress value regardless of the firmness of the tested cultivar. The toughness of the apple tissue depended on firmness and was larger under the quasi-static loading conditions for the apples with larger firmness. However, under the impact loading conditions, the toughness was greater for the apples with smaller firmness.

Maintaining the Quality of ‘Red Jonaprince’ Apples during Storage by 1-Methylcyclopropene Preharvest and Postharvest Treatment

‘Red Jonaprince’ cultivar production is rapidly increasing; therefore, the interest in harvesting in various regions, as well as in improving and maintaining the quality of the apple, is also increasing. The aim of this study was to analyze the possibility of applying 1-MCP treatment in pre- and postharvest treatment for ‘Red Jonaprince’ apples for maintaining the quality of the apple after Ultra-Low Oxygen (ULO) storage. The studied apples were assessed in four groups: 0—control group without any specific treatment applied; group 1—1-MCP applied preharvest; group 2—1-MCP applied postharvest; group 3—1-MCP applied preharvest and postharvest. Measurements were conducted directly after 3, 5 and 6 months of ULO storage and additionally after 7 days of simulated distribution for each period of storage. The 24 groups obtained (four treatments × three storage periods × two simulated distribution periods) were evaluated for firmness, soluble solids content (SSC) and titratable acidity (TA). No statistically significant impact on the SSC of ‘Red Jonaprince’ for all groups was stated (p > 0.05), while for the firmness and TA values, there was a statistically significant impact of applied treatment (ULO storage period and simulated distribution) (p < 0.05). Longer ULO storage as well as longer simulated distribution were associated with decreasing firmness and decreasing TA of apples (p < 0.05). For samples subjected to 1-MCP treatment postharvest and those subjected to 1-MCP treatment preharvest and postharvest combined, the apples in the majority of analyses were protected against decreasing firmness and decreasing TA. It may be concluded that postharvest 1-MCP treatment applied for ‘Red Jonaprince’ apples allows maintaining its quality parameters, including firmness and TA of fruits. Taking this into account, our recommendation is that the postharvest 1-MCP treatment should be sufficient, in order to avoid unreasonable management of 1-MCP, which is not justified to be applied preharvest, or preharvest and postharvest combined, for ‘Red Jonaprince’ apples.

Non-destructive near infrared spectroscopy externally validated using large number sets for creation of robust calibration models enabling prediction of apple firmness

Non-invasive flesh firmness prediction using near infrared spectroscopy has been perfected and validated on three apple varieties. Three novel calibration models were developed following three year's of repeated large-scale sampling of stored commercial apple varieties ‘Gala’, ‘Red Jonaprince’ and ‘Jonagored’. The spectroscopic results were compared directly with those obtained using the invasive method. Increased accuracy of calibration models was achieved with the newly established data collection model. The results exhibited coefficient of determination for calibration, R2, and ratio of prediction to deviation (RPD) in excess of 0.91 and 2.3, respectively, thus enabling excellent prediction of flesh firmness via a non-invasive and fast spectroscopic approach. The highest R2 obtained was 0.94, RPD 2.6, root mean square error of calibration 5.87 N, and root mean square error of cross-validation (internal) 6.75 N for variety ‘Red Jonaprince’. Our complex long-term study provided excellent external validated calibration models and the approach can help developing calibration models for commercial sorting lines using near infrared spectroscopy.

Preharvest iodine sprays at high rates are more effective in biofortification of apples than soil application

AimAgronomic biofortification of fruit with iodine (I) has become an innovative approach in contemporary agriculture. In this study, we evaluated the influence of soil- and foliar I applications on absorption of this nutrient by apple (Malus domestica Borth.) trees, as well as on growth and yield responses of the plants.MethodsIn 2018–2019, ‘Red Jonaprince’ apple trees, grown on sandy loam soil, were treated with potassium iodide (KI) or K-iodate (KIO3) through soil application (at a rate of 4 kg, 8 kg or 12 kg I ha−1) or preharvest sprays (at a rate of 0.5 kg, 1 kg or 1.5 kg I ha−1).ResultsThe I sprays increased apple I contents to the targeted range of 50–100 µg 100 g−1 fresh weight and even to the recommended daily intake of I for adults (the KI sprays at rates of 1 kg and 1.5 kg I ha−1). Although the I sprays caused leaf injuries, they did not affect tree growth and yield. However, the spray of KI and KIO3 at the highest rate decreased the soluble solid concentration in fruit. For soil-supplied trees with I, an increase in apple I concentration was found only in the first year of the study.ConclusionsApple tree is a suitable target plant for agronomic I biofortification, and from the economic point of view, the spray of KI or KIO3 at a rate of 0.5 kg I ha−1 should be recommended in orchards.

Incidence of postharvest fungal diseases of apples in integrated fruit production

In 2014–2017 an investigation was carried out into the occurrence of fungal storage diseases of five apple varieties (Red Jonaprince, Gala, Golden Delicious, Gloster and Ligol) in the Sandomierz orchard region. The fruit was stored at a CA cold storage room with ULO controlled atmosphere for six months. Occurrence of eight storage diseases was found. The most frequently occurring disease was bull’s eye rot and the losses caused thereby were even 24% of the affected fruit. The cultivars most susceptible to this disease were the Golden Delicious and Ligol apples; the least susceptible were the Gloster ones. The apples were significantly less affected by the fungi that cause brown rot, grey mould rot, blue mould rot and apple scab. Very seldom were the symptoms of calyx end rot, mouldy core and core rot, and anthracnose. Varying severity of infection of the varieties was noted in each season of observation.

Efficiency of metamitron as postbloom thinner in ‘Red Jonaprince’ and ‘Golden Delicious’

Efficiency of metamitron as postbloom thinner in ‘Red Jonaprince’ and ‘Golden Delicious’

Analysis of Possibility to Apply Preharvest 1-Methylcyclopropene (1-MCP) Treatment to Delay Harvesting of Red Jonaprince Apples

The production of Red Jonaprince cultivar is increasing, but the quality of apples is still challenging. Therefore, various options may be used including 1-Methylcyclopropene (1-MCP) application, as it influences ethylene receptors and blocks them, resulting in the possibility of delaying harvesting. The preharvest application of 1-MCP has not been studied so far for this cultivar but for other ones it has been successful, as it is based on the understanding of the natural apple ripening process. The study aimed to analyze the possibility of applying a 1-MCP treatment in the preharvest period for Red Jonaprince apples. The study was conducted based on a comparison of apples from two groups of Red Jonaprince apple trees (4 years) cultivated in an experimental orchard, where for one of them 1-MCP was applied in the preharvest period (HarvistaTM; 150 g per ha; 20 September—12 days before the optimum harvesting window (OHW)). For both groups, the apples were studied twice, for harvesting in the OHW (2 October) and for delayed harvesting (24 October). The harvested fruits were stored in an Ultra Low Oxygen chamber (ULO; 1.2% CO2, 1.2% O2) until May. They were analyzed before storage (preharvest) five times (20 September–24 October) and after storage (postharvest) three times (20 March–18 May). The following parameters were included: firmness, total soluble solids (TSS) content, titratable acidity (TA). For the preharvest period, the parameters also included internal ethylene content (IEC), starch index, and Streif index. For the preharvest period, significant differences associated with the 1-MCP treatment (p ≤ 0.05) were observed for the IEC (lower results for apples treated for 4th and 5th assessment), TA (higher results), and Streif index (higher results). Meanwhile, for firmness, TSS, and starch index for the majority of measurements there were no differences (p > 0.05). For the postharvest period, significant differences associated with 1-MCP treatment (p ≤ 0.05) were observed for firmness (higher results) and TA (higher results) both for OHW and delayed harvesting. It was concluded that a preharvest 1-MCP treatment allowed delayed harvesting and reduced the quality deterioration during the ULO storage of Red Jonaprince apples.

Effects of molybdenum sprays on the growth, yield and fruit quality of ‘Red Jonaprince’ apple trees

The aim of the study was to examine the responses of mature ‘Red Jonaprince’ apple (Malus domestica Borkh.) trees/M.26 to molybdenum (Mo) sprays. The experiment was conducted in Central Poland in 2017-2018 at high-density orchard growing on strongly acidified coarse-textured soil with low Mo availability. Trees were sprayed with Mo in the form of sodium molybdate before bloom (at pink bud), at bloom (when 5-20% of flowers were open) or after bloom (14 days after petal fall). In each spray, the Mo rate was 286 g ha-1. Trees that were not treated with Mo served as the control. Except for manganese (Mn), the concentrations of the essential macro- and micronutrients in the summer leaves of the control trees were within optimum/sufficient ranges. The summer leaf Mn concentrations were high but not toxic. Prebloom and bloom Mo sprays increased the activity of nitrate reductase (NR) and SPAD chlorophylometer values for leaves at 21 days after full bloom (DAFB), Mo concentrations in flowers and seeds, the number of seeds in an apple, fruit Ca concentration (on average by 23% for both Mo spray treatments), and the Streif index values of the fruit at harvest. The postbloom Mo spray increased the summer leaf concentrations of nitrogen, magnesium, iron and Mo, and the NR activity and SPAD values of leaves at 21 DAFB and at harvest. No Mo spray affected tree vigour, fruit set and yield, mean fruit weight, skin russeting and blushing, and the soluble solids concentration and flesh firmness of apples at harvest. It is concluded that when the apple flower Mo concentration, at least in triploid varieties, is as low as 1.5 mg kg-1 DW, a prebloom or bloom Mo spray is recommended to improve Ca-related apple quality.

Investigations on the Effects of Low Laser Infrared Marking Energy and Barcode Size on 2D Data Matrix Code Detection on Apples

HighlightsLaser energy, type of marking on the product and product color affected the Data Matrix detectionHigh laser marking energy resulted in ablation, browning and carbonizationWorking direction of the laser beam affected the print growth of the Data MatrixProposed algorithm successfully decoded the barcodes on Golden Delicious applesAbstract. Product marking in horticulture aims at providing robust and permanent means of marking products and preventing theft, tampering and cheating by customers. Direct part marking has sought to provide solutions to these problems. However, unlike in industry where it has been successful, in horticulture there are still a lot of challenges that prevent successful marking and reading of directly marked barcodes on horticultural products. The laser energy, barcode size, product color and days of storage are important factors that affect the marking, quality and readability of directly marked Data Matrix (DM) on apples. Therefore, the objective of this study was to solve the aforementioned problems with these factors by using Synrad 48-5 CO2 laser (10,600 nm), to mark some apples using low energy levels. Laser energy, the skin of the product and the inertia of the laser beam affected the printing of the DM on the apples. Incomplete marking of the DM at some of the energies used resulted in the DM not being decoded. Generally, there was successful decoding on Golden Delicious compared to Kanzi and Red Jonaprince for 10 days of storage. On the average, the smaller barcode size produced a better detection of the code than the bigger size. The better detection on Golden Delicious can be attributed to the better contrast between the DM and its color. As the days of storage increased, detection decreased for Kanzi and Red Jonaprince. There is a future prospect for directly reading marked apples in real production systems. Keywords: Apple, Apple skin, Barcode size, Data matrix, Laser, Product marking.

INFLUENCE OF 1-METHYLOCYCLOPROPENE (1-MCP) ON THE QUALITY AND STORABILITY OF ‘RED JONAPRINCE’ APPLES STORED IN DIFFERENT CONDITIONS

The research was carried out on apples of the cultivar ‘Red Jonaprince’ in two storage seasons of 2015/2016 and 2016/2017. Both 1-MCP-treated and untreated apples were stored for 120 and 150 days at 2°C and 90–92% relative humidity in a regular cold store (NA) and in two atmospheric controlled storages, i.e. 2% CO2 and 2% O2 (CA) and 2% CO2 and 1.2% O2 (ULO). Apples were evaluated directly after the storage and after 7 days of simulated shelf-life. It was shown that storage conditions had significant impact on the value of apple quality traits. The effectiveness of the post-harvest 1-MCP treatment of apples manifested in different manner depending on the tested trait and storage conditions. 1-MCP delayed the softening of apples, but only those stored in CA and ULO. It effectively limited the decrease in titratable acidity, especially of apples from NA and ULO. A positive effect of 1-MCP in NA conditions on the soluble solids content was observed, as well as a reduction in the natural loss of weight and the percentage of fruits with the symptoms of fungal decay.

Behavior of fluopyram and tebuconazole and some selected pesticides in ripe apples and consumer exposure assessment in the applied crop protection framework.

The supervised field trials were conducted in a commercial apple orchard in 2016. The trials were an attempt to determine a model for dissipation and toxicological evaluation of fluopyram, tebuconazole, captan, tetrahydrophthalimide (THPI), pirimicarb, spirodiclofen, and boscalid residues detected in fruit of Red Jonaprince, Lobo, and Gala varieties immediately before harvest. The analysis also covered amounts of pesticides still present in remnants of calyx in Lobo and Gala varieties immediately before harvest. Laboratory samples of ripe apples were collected within 14days of the treatment. Levels of pesticide residues detected in the samples changed at a constant exponential rate, and the residue levels found in ripe apples of Red Jonaprince, Gala, and Lobo varieties immediately before harvest were below maximum residue levels (MRL). Overall, captan residues in remnants of calyx were at a level of 22.3% for the Gala variety and 9.3% for the Lobo variety. Likewise, the long-term daily intake of the detected substances by a Polish adult consumer was low, ranging from 0.02% ADI for pirimicarb to 0.72% ADI for captan.