Agrology Success Stories: Color and Firmness Improvement in Fuji Apples

Michailidis Michail1, Karagiannis Evaggelos1, Pirotis Stavros2, Molasiotis Athanasios1

1 Arboriculture Workshop, Department of Agriculture, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece

2 Agrology ΑΒΕΕ, ΒΙ.ΠΕ.Θ. 570 22, Sindos, Greece

Red color is one of the main qualities in red apple varieties. Consumers prefer and choose apples mainly based on appearance, which is determined by the quality of the red coloring and the percentage of red fruit coating (Lancaster and Dougall, 1992). The dominant colorants responsible for the red coloration of the apples, not only contribute to the better appearance of the fruits, but at the same time enhance the metabolism and prevent cardiovascular problems in the human body (de Pascual-Teresa et al., 2010).

The colorants formation and development in apples has been the subject of research for nearly a century (Fletcher, 1929) and depends on a variety of factors. The most important of these is the exposure of plants to abiotic stress, such as UV radiation (Arakawa et al., 1985), the difference in maximum and minimum daily temperatures (Blankenship, 1987) and the nutritional state of the tree (Chun, 2002).

Success Story Goals

To improve the coloration of Fuji apples cultivated in lowland areas, where red color development is usually incomplete, the effect of  Suprafix® PhosCa (E2DA® Technology – Agrology) on the development of red apple variety Fuji Nagafu 12 was studied, as well as its effect on post harvest fruit preservation. This variety was chosen as it lacks red color development, especially when grown in lowland areas.

General Information of Success Story 

  • Head of Success Story: Molasiotis Ath., Arboriculture Laboratory, Department of Agriculture AUTH
  • Crop Period: 2016
  • Location: Alexandria, Imathia
  • Crop: Apple
  • Variety: Fuji Nagafu 12
  • Trees Age: 15 years
  • Configuration Form: Linear Palmette

Special Nutrition Program  

The formulation was applied to a commercial orchard in Alexandria region on 15-year-old trees, ‘Fuji Nagafu 12’, in the form of a linear pulse modulation. Firstly, 5 trees were selected for the application that was foliar performed, with the solution applied at a pressure of 2.5 psi. The product was applied 14 days and 7 days before harvest (harvest date 29/9/2016) at a concentration of 40 cc Suprafix® PhosCa in 8 liters of spray solution.

The sampling of the fruits took place on the day of harvest in two zones (1st low zone: harvesting fruit on the tree up to 1.7 meters from the ground, 2nd high zone: harvesting fruit on the tree that was above 1.7 measures from the ground). In total, 140 kg of apples were harvested, approximately 70 kg per application (control and preparation), of which 35 kg were placed in the low zone and 35 kg in the high zone.

Measurements

After harvest, the Fuji apples were transported to the laboratory, where a color determination was carried out. Color evaluation was performed with a colorimeter (model Minolta CR-200 Minolta, Osaka, Japan) in 150 apple fruits in Agrology treatment and in 150 apple fruits in the control, which was calibrated using a standard factory white plate, and the measurements were taken by placing the colorimetre head in the red side of the apple fruits. The values in the coordinate system a * were then recorded. The a * value represents the color gradient from green (a * negative) to red (a * positive).

In addition, a visual evaluation of 50 fruits with 3 replications per treatment was performed for the coating of the fruits in red in 3 classes

  • 1st class: fruits with a percentage of red hue of 0% to 20%
  • 2nd class: fruits with a percentage of red hue of 20% to 50%
  • 3rd class: fruits with a percentage of red hue of 50% to 100%

Subsequently, flesh consistency was determined (Friction Firmness Tester). After 2, 4 and 6 months of cold preservation at 0 ° C, determination of flesh consistency, percentage of coating and color was also performed.

Statistical analysis was performed (ANOVA) using the SPSS statistical packet (SPSSv21.0., Chicago, USA).

Success Story Results 

  • Improve the Fuji apples’ Red Color by 300% compared to the Control!  
  • Increase apples Shelf-life by 3.5 Months!  
  • Highest Resistance to Mechanical Pressure (Hardness) when preserved on cooling for 2.4 and 6 months!  
  • Improvement of the Quantitative Coating in red on the total surface of the fruit (% of the red-colored coating of the fruit)!

Conclusions 

The application of Suprafix® PhosCa to this Success Story has contributed to:

  • Improve the Apples Red Color by 300% compared to the Control!

It was found that the Suprafix® PhosCa application increased the red color compared to the control. The application affected positively the development of intense red color (α * color) compared to the control (Picture 1).

Picture 1. Red color indicator. Skin Red color of 150 apples per treatment. Carpophos® showed 300% improvement in red color compared to Control.
11Picture 1. Red color indicator. Skin Red color of 150 apples per treatment. Carpophos® showed 300% improvement in red color compared to Control.

Picture 1. Red color indicator. Red apple skin color of 150 apples per treatment. An improvement in the red color of the fruits was observed by the application of Suprafix® PhosCa by 300% compared with the Control.

  • Increase of Apples flesh Firmness by 3.5 Months!

In the visual evaluation of the red apple coating ‘Fuji Nagafu 12’, Suprafix® PhosCa was differentiated from 0 to 20% and 50 to 100% in comparison with the Control. The Control Fuji apples classified as 1st class accounted for 65%, whereas the Suprafix® PhosCa treated apples in the same class was 17%. In the third class, which was the Success Story’s goal, the Control had 5%, while in the same class the fruits treated with Suprafix® PhosCa ranged above 40% of the fruits (Picture 2).

Carpophos πείραμα
Carpophos πείραμα

Picture 2. Red skin coat of 150 apples (75 low and 75 high tree zone) per treatment. Statistically significant (*) differences were found based on T-test (T-test) for independent samples at significance level P ≤ 0,05. On the right side (top picture), apples that have been treated with Suprafix® PhosCa have been identified. On the left side are the apples used as a Control.

  • Higher Resistance of Flesh to Mechanical Pressure (Hardness) in the preservation of apples in refrigeration for 2,4 and 6 months!

With the Suprafix® PhosCaan increase in Fuji apples preservability by 3,5 months was observed. With the application of the Agrology Special Nutrition Programs, a higher resistance to mechanical stress of the fruit flesh was measured, even after 6 months of cold preservation.

Picture 3. Resistance to mechanical pressure
Picture 3. Resistance to mechanical pressure

Picture 3. Apple resistance in mechanical Pressure. With the application of Suprafix® PhosCa, a higher resistance to mechanical stress of the fruit flesh was measured, even after 6 months of cold preservation.

  • Improvement of the Quantitative Coating in red on the total surface of the fruit (% of the red-colored coating of the fruit)!

The Suprafix® PhosCa presented differences compared to the Control regarding the fruit’s color parameters after cold preservation (0 ° C). In particular, an increased red color was recorded, expressed by the color parameters a * and Hue angle (Figure 4 A and C). Also, an increase in the red color coverage rate, which varied in percentages that exceeded 45% for Suprafix® PhosCa was observed and varied at all time points relative to the Control (Picture4B).

Effect of Suprafix® PhosCa on post-harvesting characteristics of apples
Effect of Suprafix® PhosCa on post-harvesting characteristics of apples

Picture 4. Effect of Suprafix® PhosCa on post-harvesting characteristics of apples. Apple color: Color display of 5 representative fruits per harvest treatment and after 2, 4 and 6 months of cold maintenance (0 ° C). Color parameters (A) Hue angle and (C) a * and (B) red colorful fruits after 2, 4 and 6 months of cold maintenance (0 ° C).

Reference List

Blankenship, S.M. (1987). Night-temperatures effects on rate of apple fruit maturation and fruit quality. Scientia Horticulturae 33, 205-212.

Fletcher, L.A. (1929). A preliminary study of the factors affecting the red color on apple. Proceedings of the Society for Horticultural Science. 26, 191-196.

Lancaster J.E. & Dougall Dr. Donald K. (1992). Regulation of skin color in apples, Critical Reviews in Plant Sciences, 10:6, 487-502.

de Pascual-Teresa S., Moreno, D. A., & García-Viguera, C. (2010). Flavanols and anthocyanins in cardiovascular health: a review of current evidence. International Journal of Molecular Sciences, 11:4, 1679-1703.

Arakawa, O., Hori, Y., & Ogata, R. (1985). Relative effectiveness and interaction of ultraviolet‐B, red and blue light in anthocyanin synthesis of apple fruit. Physiologia Plantarum, 64:3, 323-327.

Chun, I. J., Fallahi, E., Colt, W. M., Shafii, B., & Tripepi, R. R. (2002). Effects of rootstocks and microsprinkler fertigation on mineral concentrations, yield, and fruit color of ‘BC-2 Fuji’apple. Journal of the American Pomological Society, 56:1, 4.

Learn more about Agrology Specialty Nutrition Programs from our specialized staff Here.

This trial was carried out under specific field conditions and should not be replicated without the guidance of an agronomist or the Technical Department of Agrology. In all cases, Agrology products and programs must be applied in accordance with the label.