Understanding the mechanisms of calcium (Ca2þ) deficiency disorder development in plants has been a challenge for more than a 100 years. Previous studies support the hypothesis that Ca2þ deficiency disorders can be triggered by mechanisms that reduce plant Ca2þ uptake from the soil, fruit Ca2þ uptake from the plant, and Ca2þ translocation within the fruit, and also result in abnormal regulation of cellular Ca2þ partitioning. Plant Ca2þ uptake can be determined by Ca2þ content and availability in the soil, root growth, activity of apoplastic and symplastic pathways of root Ca2þ uptake, as well as uptake competition between Ca2þ and other nutrients. Fruit Ca2þ uptake is determined by Ca2þ content in the xylem sap, and xylem/phloem ratio of fruit sap uptake, which is affected by the rates of leaf and fruit transpiration and growth. Calcium translocation to distal fruit tissue, containing the lowest fruit Ca2þ content and the highest susceptibility to Ca2þ deficiency disorders, is potentially dependent on the cell wall Ca2þ-binding capacity and symplastic Ca2þ uptake by the tissue at the peduncle end of the fruit, abundance of functional xylem vessels connecting peduncle and distal fruit tissues, as well as the hydrostatic gradient required for Ca2þ translocation towards the distal tissue. Cellular Ca2þ partitioning is defined by the activity of Ca2þ channels, Ca2þ ATPases, and Ca2þ exchangers present in cellular membranes, as well as the capacity of the cell wall to bind Ca2þ, and the formation of Ca2þ precipitates in different cellular compartments. Therefore, 107 Horticultural Reviews, Volume 40, First Edition. Edited by Jules Janick. 2012 Wiley-Blackwell. Published 2012 by John Wiley & Sons, Inc. Ca2þ deficiency disorders in fruit may not be caused by a single factor, but most likely by a combination of mechanisms that lower Ca2þ concentration at a specific tissue and cell localization, leading to Ca2þ deficiency symptoms.

Factors Involved in Fruit Calcium Deficiency Disorders

Combination of strategies to supply calcium and reduce bitter pit in ‘Golden Delicious’ apples

Calcium (Ca) sprays are commonly used to control Ca-related disorders such as bitter pit in apple. Increases in the frequency and the amount of Ca applied directly to the fruit have increased fruit Ca levels and are associated with a reduction in bitter pit incidence.
However, the absorption efficiency at different fruit developmental stages is poorly understood. Here, the absorption efficiency was measured using Ca-44 stable isotope applied to 30 individual fruit at five different times every 2 weeks between June drop and 2 weeks before harvest in a medium-density 'Honeycrisp' orchard. Fruit size, spray adhesion, and Ca and potassium (K) content were monitored weekly for 12 weeks between 26 May and 13 Aug. 2015. At harvest, the Ca-44-labeled fruit was picked and separated into peel and inner fruit for mass balance analysis of Ca-44 absorption to regions of the fruit that are important to prevent Ca-related disorders.
As expected, delta Ca-44 was greater in the peel than the interior of the fruit. However, there was a significant amount of Ca-44 present in the inner fruit at harvest for all five applications applied during the growing season. Using a stable isotope tracer approach, we present evidence that Ca is absorbed throughout fruit development.
These findings support current recommendations for frequent Ca applications in low concentrations throughout fruit development to increase fruit Ca levels and reduce the incidence of bitter pit in 'Honeycrisp' apple.

/pdf/calcium-absorption-during-fruit-development-in-honeycrisp-3s9mmbeypq.pdf

Calcium Absorption during Fruit Development in ‘Honeycrisp’ Apple Measured Using 44Ca as a Stable Isotope Tracer

https://digital.csic.es/bitstream/10261/28839/1/BlancoA__2010.pdf

Improving the performance of calcium-containing spray formulations to limit the incidence of bitter pit in apple (Malus x domestica Borkh.)

Nutritional unbalances, such as calcium deficiency at the fruit level, are generally the causative agent of post-harvest disorders in apples. Foliar application of Ca as calcium chloride is the current solution to increase Ca concentration in apples, even though the effectiveness of this approach is often not satisfactory. In this research, we tested the efficacy of a combined application of Ca with selected biostimulants to improve apple quality and to reduce the incidence of storage disorders. The experiment was conducted in two “Jonathan” apple orchards that differed in management systems and characteristics. Tree canopies were sprayed with calcium chloride alone and in combination with a commercial product containing zinc and silicon or a seaweed extract. The seaweed extract increased apple quality by boosting the reddish coloration (+32% of color index) and by enhancing final anthocyanin concentration of fruit skin. Both biostimulants significantly reduced (by 20%) the incidence of the physiological disorder, known as “Jonathan spot”, after 160 days of storage. Increased concentration of nutrients (Ca, Zn, and Mn) in the skin of apples after biostimulant applications, together with changes of the phenolic profile during the storage, are discussed as the possible causes of the reduced fruit susceptibility to post-harvest disorders.

https://www.mdpi.com/2073-4395/10/8/1214/pdf

Effect of Biostimulants on Apple Quality at Harvest and After Storage

Evaluating pre-harvest foliar calcium applications to increase fruit calcium and reduce bitter pit in Golden Delicious apples.

Although management practices are followed to reduce the incidence of bitter pit in commercial orchards, this defect still surfaces and causes serious problems with fruit quality that lead to losses in especially export produce. Current methods e.g. fruit mineral analysis, magnesium (Mg) infiltration and ethylene forcing that were developed to predict bitter pit incidence, vary in reliability. However, there is still a need to predict bitter pit incidence, before it becomes visible. The effectiveness of ethylene forcing and Mg infiltration - were assessed under local conditions for 'Braeburn' and 'Golden Delicious' apples. The correlation coefficients for the two methods were compared, as well as the correlations between the bitter pit-like incidence induced by the individual methods and actual bitter pit after storage. During the first season, the coefficient determination for Mg infiltration and actual bitter pit (R 2 = 0.45) was higher compared to the coefficient for ethylene forcing and actual bitter pit (R = 0.13). The R for the linear relationship between bitter pit incidence with Mg-infiltration and ethylene forcing was 0.43. The actual bitter pit incidence per season influenced the accuracy of the methods.

Assessment of pre-harvest physiological infiltration methods for predicting commercial bitter pit in 'Braeburn' and 'Golden Delicious'

Our export apple producers must apply calcium (Ca) sprays to reduce the incidence of the Ca deficiency-related physiological disorder bitter pit. Conflicting reports exist as to the optimal timing of these Ca sprays and benefits of adjuvant use on Ca uptake into the fruit. Four adjuvants were evaluated and compared to an unsprayed control, adjuvant-free treatment and commercially used adjuvant Agral-90 ® , together with calcium nitrate (Ca(NO3)2) sprays, applied at six weekly intervals. The adjuvants were evaluated in terms of their efficacy in facilitating the entry of Ca into apple fruit early in the season and the resulting effects thereof on fruit quality as quantified by bitter pit incidence and retiform russet. The average fruit Ca concentration decreased by ~ 30% from 40 days after full bloom (DAFB) to below Terblanche et al.’s (1980) proposed threshold of 6.6 mg -1 .100g fresh weight (FW) for Casprayed apples at harvest. Nevertheless, very little bitter pit occurred. Seasonal average fruit Ca concentrations were ~20% higher in Ca(NO3)2 without adjuvant treatment, than in fruit receiving no Ca(NO3)2, confirming that external Ca applied between 40 and 80 days after full bloom was taken up by the fruit. None of the adjuvants evaluated improved fruit Ca concentration when added to Ca(NO3)2 sprays at any monitoring date. Only the penetrant ‘Partner R A’ and humectant ‘NPX’ treatment showed potential to promote Ca uptake.

Adjuvants and application date of calcium nitrate sprays effect Golden Delicious fruit calcium concentration.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

J. Joubert

Author Tools

Chat about Author

Papers

Evaluating pre-harvest foliar calcium applications to increase fruit calcium and reduce bitter pit in Golden Delicious apples.

Assessment of pre-harvest physiological infiltration methods for predicting commercial bitter pit in 'Braeburn' and 'Golden Delicious'

Adjuvants and application date of calcium nitrate sprays effect Golden Delicious fruit calcium concentration.