Large Perennial Fruit tree for quality yield on citrus

Study Investigator: John Curtis, PhD

Location of Study: Florida, USA, open field

Study Period: March - November 2014

App 1

1 Quart/Acre


App 2

1 Quart/Acre


App 3

1 Quart/Acre


App 4

1 Pint/Acre


App 5

1 Pint/Acre

Color Break

1 Qt/acre

Bloom 50%

+1 Qt/acre

Bloom 50%

2 Quarts/acre at Bloom 50%

1 Qt/acre


+1 Qt/acre


2 Qts/acre at Post-Bloom


2 programs tested: Program A (4 applications at 1 quart/acre), Program B (2 applications @ 2 quarts/acre) 

  • Block of 25 acres located Indian river district, FL USA


  • 1 row is 47 trees
  • 5 rows per treatment
  • 235 trees per treatment for 1 replicate
  • Rows: a;b;c;d;e
  • Treatments :
    • T1) Program (Qt per acre and Pint/acre)
    • T2) Program (2 Qts per acre)


  • Replicated x5 times per treatment
  • The 5 rows per treatment are randomized each time
  • Example, T1, replicate # 1 and the 5 rows are as follow:
    • R1 = Row Grower Standard
    • R2 = Row T1
    • R3 = Row T2
    • R4 = Row T1
    • R5 = Row T2
  • Each replicate then present a different order of the row via a scientific randomization.

 Total tree monitored:

  • 1,175 trees per treatment replicated 5 times
  • 2,350 trees total (2 treatments replicated 5 times) 
Juice & Brix data
  • All fruit data for juice content and pound solids was gathered by an independent packing house within Indian River District. 

  • Cyan 365® has been sprayed by conventional sprayer : rear pak- blast sprayer, 250 GPA

IFAS equipment

This study is even more outstanding because of the exceptional use of the IFAS mobile packing unit invented by Dr Rouse University of Florida. This mobile packing unit gives a high reliability of this agronomic study. Packing houses is usually where the results are severily corrupted.

Early Fruit Drop (EFD)

One of the vicious effects of HLB is a noticeable increase in mature quality fruit drop. On infected trees, there is a serious decrease in the number of flowers that will set fruit and mature into marketable quality fruit.

Mid-June Fruit Drop (natural drop due to fruit competition)increases.

With HLB disease, early fruit drop is about 25-30% (Source: USDA, 2013).

The trees infected with HLB are experiencing more and more fruit drop.

Fruit quality is affected.

Contaminated trees have smaller fruit and internal quality is suffering.

Profit wise, it is extremely detrimental for the growers and the industry in general  ...

Bitter Taste with HLB

Another side effect from HLB: the bitter taste of the juice.

The fruit show an significant decrease in sugar content. (brix, fructose - pound solids). This is a big issue for both fresh and juice producers within the citrus industry.

Study Results


Boxes per acre (TPA 120) of extra yield with Cyan 365®


Fruits on average per acre (TPA 120) with Cyan 365®


Box on average per tree with Cyan 365®


Fruit on average per tree with Cyan 365®


Extra Yield with 3 applications @ 1 quart/acre +1 pint/acre at summer and 1 Pint/acre at fall


Less Early Fruit Drop with Cyan 365®


Less pieces of fruit per tree in Avg. (EFD) with Cyan 365®


More viable bearing fruit found on average per tree (count @ fall)


Per acre as ROI (Market price index of 2014) with Cyan 365®

Agronomic study conducted from March to November 2014 and repeated with the same protocol in 2016. All operations were supervised and controlled by scientist John Curtis with his independent technical crew. The property used was a highly-reputed citrus grower’s commercial grove within the Indian River District (Florida).

THE PROGRAM [A] showed better results than program [B].

Here under results for program [A]:

Quality yield:

  • +96 boxes (+25%) extra yield of fruit per acre (TPA 120) Vs grower std.
  • +0.8 box per tree (+25%) extra yield of fruit per acre Vs grower std.
  • +66 fruit count per tree in average Vs the grower std.
  • +8,000 pieces of fruit per acre Vs the grower std.
  • -23% early fruit drop Vs the grover std.
  • -16 Early fruit drop count per tree in average.
  • +114% viable bearing fruit count.

Quality fruit:

  • +15% & +11% juice content respectively for the 40's and 32's sizes. (most significant for these 2 marketable sizes)
  • We have noticed significant improvements of Brix/Lbs solids for the sizes of 56's and 40's, respectively, +13% and +25%.
  • The Brix/Lbs solids data remains to be studied more extensively.

Fruit size distribution:

The AVERAGE fruit size breakdown per TREE provides significant improvement on the packout for the most valuable sizes:

  • + 75 pieces per tree, distributed as per graph. 

Return On Investment (ROI):

  • +$800 per acre

Notes: It is noticeable that for fresh fruits market, fruit size distribution results should be added to this $800 per acre.


Objectives: Ray Ruby red grapefruit on sour orange rootstock, 6 YO trees, severely affected by HLB, canker resurgence, early fruit drop, leafminer, melanoses, greasy spots, rust mites, etc.

For a better view of the graphs and charts, reposition your mobile device into landscape mode.

Variety Used: Ruby red grape fruit on sour orange rootstock, 6 YO trees, severely touched by HLB, canker resurgences, premature fruit drop, leaf minor...

Extra yield Vs. Grower standard with Cyan 365® Prog. A: is 96 boxes per acre.

With an increase of 0.8 boxes per tree, you will increase your total box count with 96 boxes per acre @ TPA 120. As you may see with more fragmented applications as per program [A] or T1 at lower dosage you will obtain the best results than the program [B] or T2.

Early Fruit Drop count (in pcs) with CYAN 365® (Prog A) Vs the Grower Std.
Early fruit drop
  • -16 pcs per tree for the prog. A with Cyan 365® and compared to the Grower Std.
  • -23% Early fruit drop for the prog. A with Cyan 365® and compared to the Grower Std.
Remaining viable fruit count on the tree
  • +114%  viable bearing fruits in average per tree treated with Cyan 365® prog. A. 
  • Technic employed of the quadron as detailed in study for early fruit drop and viable remaining fruit.
  • Fruit count made after the natural fruit competition which is occuring for Grapefruit around mid-June
  • Fruit count made in September.
Fruit size distribution with CYAN 365®

For the extra yield obtained with Prog A with Cyan 365® (+75 pieces of fruit per tree), the distribution of the fruit size is as here under (photo). In the meantime it is very important to notice here the presence of a mobile packing house unit lended to Dr Curtis by the University of Florida (Dr Rouse equipment). This equipment allow to give a higher credibility and reliability to this scientific and agronomic study.

The fruit size distribution is showing here the abilty of Cyan 365® to improve the sizes of the fruits in the most marketable and valuable sizes.

different sizes of oranges

For fresh, fruit size results here above must be taken into consideration to achieve an even better Return on Investment.

Quality Fruits with CYAN 365®: Juice Content

Juice content: +15% & 11% respectively on 40's and 32's. The juice content has improved the most on these 2 sizes.

Quality Fruits with CYAN 365®: Pound Solids/Brix Ratio

Pound solids/Brix: +13% on 56's and +25% on 40's. It is commonly accepted that larger the fruit are, less brix there is. Note: 7.50 is the flat rate for November 2014 for Grape fruit (GF) within Indian river district, county Port Saint Lucie. The flat rate is transmitted each season each year to the packing houses. These data remains to be studied more extensively.