Fruit canopy positioning affects fruit calcium and potassium concentrations, disorder incidence, and fruit quality for ‘Honeycrisp’ apple

2019 ◽  
Vol 99 (5) ◽  
pp. 761-771 ◽  
Author(s):  
Lee Kalcsits ◽  
James Mattheis ◽  
Luca Giordani ◽  
Michelle Reid ◽  
Katie Mullin

One advantage of high-density apple orchard systems is homogeneity in fruit maturity and quality. However, even in modern orchard systems, variation in fruit quality occurs. ‘Honeycrisp’ apple is susceptible to numerous disorders including bitter pit, soft scald, and poor colour development. Heterogeneity in fruit quality and nutrient distribution can lead to variation in fruit storability. Here, we tested the effect of within-canopy position on fruit calcium and potassium concentrations, quality, and disorder development for fruit across nine representative high-density orchards. Calcium concentrations were greater in the upper part of the canopy compared with the lower part. Potassium was more evenly distributed within the canopy. Calcium concentrations and potassium-to-calcium ratios were significantly correlated with mean bitter pit incidence, which was between 20% and 30% in the lower half of the tree and <15% in the upper half. Fruit quality was significantly affected by the position in the canopy and was not constrained to only colour, but also other quality metrics such as dry matter, size, and firmness. Additionally, the internal ethylene concentrations (IECs) of fruit in the upper canopy were approximately 50% of the IECs for fruit from the lower canopy. With an increased emphasis on uniformity and predictability of fruit for long-term storage, these results underscore the importance of understanding variation within the canopy. Even for high-density systems, significant variation in fruit quality can occur and fruit from the upper canopy has lower disorder incidence and higher fruit quality than fruit from the lower canopy.

2017 ◽  
Vol 45 (1) ◽  
pp. 120-125 ◽  
Author(s):  
Ersin ATAY ◽  
Seckin GARGIN ◽  
Ahmet ESITKEN ◽  
N. Pinar GUZEL ◽  
A. Nilgun ATAY ◽  
...  

Orchard performance is influenced by weed competition. In this study, the effects of weed competition on nutrient contents, chemical and physical fruit quality properties were sought. The study was carried out in a high-density apple orchard (‘Golden Delicious’/M.9) over two consecutive growing seasons. The effect of weed competition was studied at three different levels: weak, moderate and strong. Fruit firmness, soluble solids content, macronutrients (such as nitrogen, potassium and calcium) and potassium+magnesium/calcium ratio in fruit were significantly affected by weed competition. Strong weed competition negatively affected soluble solids content and potassium+magnesium/calcium ratio. In both trial years, soluble solids content was significantly higher in weak weed competition. In the first year of the study, soluble solids content ranged between 13.77±0.06% (strong weed competition) and 15.20±0.10% (weak weed competition). In the following year, soluble solids content values were determined as 13.13±0.23% in strong weed competition and 13.83±0.21% in weak weed competition. Weak weed competition showed superiority for fruit weight and potassium+magnesium/calcium ratio. As a whole, this study indicates that insufficient weed control in tree rows might be a limiting factor for fruit quality in high-density apple orchards.


Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 732
Author(s):  
Xiaohu Jiang ◽  
Long He

Irrigation helps grow agricultural crops in dry areas and during periods of inadequate rainfall. Proper irrigation could improve both crop productivity and produce quality. For high density apple orchards, water relations are even more important. Most irrigation in tree fruit orchards is applied based on grower’s experience or simple observations, which may lead to over- or under-irrigation. To investigate an effective irrigation strategy in high-density apple orchard, three irrigation methods were tested including soil moisture-based, evapotranspiration (ET)-based and conventional methods. In soil moisture-based irrigation, soil water content and soil water potential sensors were measured side by side. In ET-based irrigation, daily ET (ETc) and accumulated water deficit were calculated. Conventional method was based on the experience of the operator. The experiment was conducted from early June through middle of October (one growing season). Lastly, water consumption, fruit yield and fruit quality were analyzed for these irrigation strategies. Results indicated that the soil moisture-based irrigation used least water, with 10.8% and 4.8% less than ET-based and conventional methods, respectively. The yield from the rows with the soil moisture-based irrigation was slightly higher than the other two, while the fruit quality was similar. The outcome from this study proved the effectiveness of using soil moisture sensors for irrigation scheduling and could be an important step for future automatic irrigation system.


HortScience ◽  
2019 ◽  
Vol 54 (5) ◽  
pp. 910-915 ◽  
Author(s):  
Rachel Leisso ◽  
Ines Hanrahan ◽  
Jim Mattheis

‘Honeycrisp’ apple is susceptible to the postharvest chilling disorder soft scald that renders fruit unmarketable. Reducing or preventing this disorder is an important component of ‘Honeycrisp’ postharvest management. In commercial settings, advanced fruit maturity and orchard history contribute to an estimation of soft scald susceptibility, but additional at-harvest information indicative of soft scald risk would enable better management decisions. In this study, we obtained fruit from commercial orchards for 3 successive years, and assessed field growing degree days (GDD), field chilling hours (CH), and fruit quality metrics at harvest, followed by soft scald incidence assessment at 12 weeks of cold storage. The analyses indicated starch index, soluble solids content (SSC), internal ethylene concentration, titratable acidity (TA), peel background color, firmness, GDD, or CH do not reliably indicate fruit susceptibility to soft scald. However, SSC and TA were elevated in fruit that later developed soft scald, and a higher number of GDD also sometimes preceded soft scald, which is consistent with advanced fruit maturity that can enhance soft scald risk. Overall, results suggest that other tools may be required to accurately predict postharvest soft scald on a quality control laboratory scale. The statistical analyses applied to the present study would have utility for assessing other soft scald prediction tools or markers.


HortScience ◽  
2010 ◽  
Vol 45 (3) ◽  
pp. 414-417 ◽  
Author(s):  
Jennifer R. DeEll ◽  
Behrouz Ehsani-Moghaddam

The main objective of this study was to investigate the effectiveness of preharvest 1-methylcyclopropene (1-MCP) treatment on the development of soft scald in ‘Honeycrisp’ apples. In addition, the effects of preharvest 1-MCP on fruit quality at harvest and after storage were examined. For two consecutive years of study, ‘Honeycrisp’ trees were sprayed preharvest with 1-MCP and fruit were harvested twice during each year. Preharvest 1-MCP treatments had little consistent effect on fruit maturity at the time of harvest. In both years of study, preharvest 1-MCP reduced the incidence of soft scald in ‘Honeycrisp’ apples after air storage at 0 or 3 °C for 5 or 6 months. Soggy breakdown developed only in the second year of study and high incidences were reduced by preharvest 1-MCP treatments. Preharvest 1-MCP often reduced flesh firmness loss in ‘Honeycrisp’ during storage, especially during the second year of study, and with 1-MCP application closer to harvest. Malic acid content was often higher in apples with the preharvest 1-MCP spray closer to harvest. Overall, the most important benefit of preharvest 1-MCP treatments on ‘Honeycrisp’ apples was the reduction in soft scald development. Due to the high potential for substantial fruit losses from this disorder, the use of preharvest 1-MCP sprays on ‘Honeycrisp’ apples could be very advantageous.


2019 ◽  
Vol 99 (4) ◽  
pp. 444-459
Author(s):  
John A. Cline

‘Honeycrisp’ apple trees are highly prone to biennial bearing and predisposed to bitter pit. The hypothesis that tank mix sprays of ethephon (ETH), naphthaleneacetic acid (NAA), and 1-aminocyclopropane carboxylic acid (ACC) combined with calcium chloride (CaCl2) can mitigate these production problems was tested in a 3-yr study. Mature ‘Honeycrisp’ trees were treated with either three or six summer applications of 150 mg L−1 ETH or 5 mg L−1 NAA, all tank-mixed with and without CaCl2, or two or five applications of 150 mg L−1 ACC (without CaCl2). Treatments were applied at 10-d intervals and initiated between 21 and 26 June. All treatments had little effect on enhancing return bloom of ‘Honeycrisp’. NAA, ETH, and CaCl2 all influenced fruit maturity and quality at harvest to varying degrees and across years. Fruit treated with NAA were firmer compared with untreated fruit in 2 out of 3 yr, whereas overall, fruit treated with six sprays of ETH had lower fruit firmness and were more mature. NAA had less influence on fruit quality attributes at harvest than did ETH, and decreased pre-harvest fruit drop (PFD). PFD increased with ETH in 1 out of 2 yr, whereas ACC and NAA both decreased PFD in 1 out of 2 yr. Overall, ETH and NAA, with or without CaCl2, had significant but inconsistent effects on fruit quality and maturity, all dependent on the year and number of applications. Adding CaCl2 decreased fruit firmness in 2 out of 3 yr.


Weed Science ◽  
2021 ◽  
pp. 1-23
Author(s):  
Katherine M. Ghantous ◽  
Hilary A. Sandler

Abstract Applying control measures when carbohydrate levels are low can decrease the likelihood of plant survival, but little is known about the carbohydrate cycles of dewberry (Rubus spp.), a problematic weed group on cranberry farms. Weedy Rubus plants were collected from areas adjacent to production beds on commercial cranberry farms in Massachusetts, two locations per year for two years. For each site and year, four entire plants were collected at five phenological stages: budbreak, full leaf expansion, flowering, fruit maturity, and after onset of dormancy. Root sections were analyzed for total nonstructural carbohydrate (TNC; starch, sucrose, fructose, and glucose). Overall trends for all sites and years showed TNC were lowest at full leaf expansion or flowering; when sampled at dormancy, TNC concentrations were greater than or equal to those measured at budbreak. Starch, a carbohydrate form associated with long-term storage, had low levels at budbreak, leaf expansion and/or flowering with a significant increase at fruit maturity and the onset of dormancy, ending at levels higher than those found at budbreak. The concentration of soluble sugars, carbohydrate forms readily usable by plants, was highest at budbreak compared to the other four phenological samplings. Overall, our findings supported the hypothesis that TNC levels within the roots of weedy Rubus plants can be predicted based on different phenological growth stages in Massachusetts. However, recommendations for timing management practices cannot be based on TNC cycles alone; other factors such as temporal proximity to dormancy may also impact Rubus plants recovery and further research is warranted. Late-season damage should allow less time for plants to replenish carbohydrate reserves (prior to the onset of dormancy), thereby likely enhancing weed management tactics effectiveness over time. Future studies should consider tracking the relationship between environmental conditions, phenological stages, and carbohydrate trends.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Molla F. Mengist ◽  
Hamed Bostan ◽  
Elisheba Young ◽  
Kristine L. Kay ◽  
Nicholas Gillitt ◽  
...  

AbstractFruit quality traits play a significant role in consumer preferences and consumption in blueberry (Vaccinium corymbosum L). The objectives of this study were to construct a high-density linkage map and to identify the underlying genetic basis of fruit quality traits in blueberry. A total of 287 F1 individuals derived from a cross between two southern highbush blueberry cultivars, ‘Reveille’ and ‘Arlen’, were phenotyped over three years (2016–2018) for fruit quality-related traits, including titratable acidity, pH, total soluble solids, and fruit weight. A high-density linkage map was constructed using 17k single nucleotide polymorphisms markers. The linkage map spanned a total of 1397 cM with an average inter-loci distance of 0.08 cM. The quantitative trait loci interval mapping based on the hidden Markov model identified 18 loci for fruit quality traits, including seven loci for fruit weight, three loci for titratable acidity, five loci for pH, and three loci for total soluble solids. Ten of these loci were detected in more than one year. These loci explained phenotypic variance ranging from 7 to 28% for titratable acidity and total soluble solid, and 8–13% for pH. However, the loci identified for fruit weight did not explain more than 10% of the phenotypic variance. We also reported the association between fruit quality traits and metabolites detected by Proton nuclear magnetic resonance analysis directly responsible for these fruit quality traits. Organic acids, citric acid, and quinic acid were significantly (P < 0.05) and positively correlated with titratable acidity. Sugar molecules showed a strong and positive correlation with total soluble solids. Overall, the study dissected the genetic basis of fruit quality traits and established an association between these fruit quality traits and metabolites.


1990 ◽  
Vol 36 (5) ◽  
pp. 783-788 ◽  
Author(s):  
M N Nanjee ◽  
N E Miller

Abstract The concentration of high-density lipoprotein cholesterol (HDL-C) in plasma is now established as an independent risk factor for coronary heart disease, but more data are needed on the relative risk-predictive powers of different HDL subclasses. For epidemiologic and clinical purposes, isolation of HDL from other lipoproteins and separation of its two major subclasses, HDL2 and HDL3, are performed most conveniently by precipitation. Although storage of plasma is commonly necessary, little information is available on the long-term stability of HDL subclasses at different temperatures. Therefore, we quantified HDL-C, HDL2-C, and HDL3-C by dual precipitation with heparin-MnCl2/15-kDa dextran sulfate (H-M/DS) in samples of EDTA-plasma from 93 healthy subjects, after storage for one to 433 days at -20 degrees C, at -70 degrees C, or in liquid nitrogen (-196 degrees C). Fourteen samples (15%) were stored for a year or longer. At -20 degrees C, HDL-C decreased by 4.8% per year and HDL3-C decreased by 6.9% per year (P = 0.002 for both variables) relative to results obtained with samples stored in liquid nitrogen; total cholesterol, HDL2-C, and triglyceride did not change significantly at this temperature. When stored at -70 degrees C, none of the lipids showed any change relative to results obtained with liquid nitrogen. Thus, long-term storage of EDTA-plasma at -20 degrees C is unsuitable for subsequent quantification of HDL-C and its subclasses by H-M/DS dual precipitation. Storage at -70 degrees C is preferable, and is as reliable as storage in liquid nitrogen.


2004 ◽  
Vol 32 (2) ◽  
pp. 213-221 ◽  
Author(s):  
Christopher B Watkins ◽  
Jacqueline F Nock ◽  
Sarah A Weis ◽  
Sastry Jayanty ◽  
Randolph M Beaudry

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