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Strawberry is being promoted for year round production due to its highly desirable taste, flavour and health properties, and it is possible through soilless cultivation. A study on production of strawberry cv. Festival under vertical growth system with four tiers on soilless medium in a passively ventilated greenhouse was attempted. Significant differences were observed for the growth parameters, viz., number of leaves, leaf area, crown diameter and biomass production. Of the four tiers, first tier planting tended to show the enhanced plant growth and photosynthesis rate with early flowering, higher fruit yield of improved fruit quality than lower tiers tested.
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Indian J. Hort. 73(2), June 2016: 300-303
Strawberry (Fragaria x ananassa Duch.) is one
of the most popular fruits around the world due to its
highly desirable taste and avour. It is widely cultivated
due to its genetic diversity, highly heterozygous
nature and broad range of environmental adaptations
(Sharma and Sharma, 8). The increased demand
for strawberries throughout the year is met through
soilless cultivation. The future of soilless culture will
depend on the development of new production systems
and substrates that are competitive in costs and returns
with conventional agriculture (Takeda, 15). The type of
containers and their arrangement inside the polyhouse
determine the growth and yield of strawberry plants.
The only way to utilize the greenhouse volume in
strawberry production is to set up a vertical production
system (Verti-Gro system) (Linsley-Noakes et al., 7).
However, sub-optimal environmental conditions in
the lower sections, result in reduced plant growth and
yield (Takeda, 9). Hydroponic culture Verti-Gro system
for growing high value crops has been in commercial
practice in countries like United States of America,
Japan, Australia and Italy. The system enables efcient
energy and greenhouse volume utilization (Al-Raisy et
al., 1). Hence, it is important to nd the most suitable
soilless cultivation system for strawberry to maximize
the utilization and distribution of light and culture
media within the system to enhance production without
affecting the fruit quality. Keeping all these benets
and constraints in view, the present investigation was
conducted to study the growth, light availability, gas
exchange, yield and quality of strawberry cv. Festival
cultivated in vertical growth system with soilless media.
The present study was carried out in a passively
ventilated greenhouse established by the Division
of Fruit Crops, ICAR-Indian Institute of Horticultural
Research, Bengaluru is situated at a latitude of
13.15°N, and longitude of 77.49°E and at an altitude
of 890 m above mean sea level. The minimum
and maximum day/ night temperature inside the
greenhouse ranged from 11.06 to 20.28˚C and 31.75
to 40.33˚C, respectively, and relative humidity between
40 to 90% during the crop growth period.
Healthy plugs of strawberry cv. Festival were
planted in vertical growth system, which consisted of
four vanilla round shaped 2.8 l capacity pots, placed
one above the other with the help of a metal pole.
The bottom pot was placed at 45 cm from the ground
and subsequent pots were placed 20 cm apart from
each other by placing PVC pipe as sleeves between
the two pots. The total height of the column was 172
cm with pots placed in four tiers. The pot at the top
position was considered as rst tier and subsequent
pots down the column as second to fourth tiers. Four
vertical growth systems were arranged in a row at 100
cm distance and distance between two rows was 70
cm. Each pot accommodated four plants and a total of
16 plants were maintained per column. The pots were
lled with soilless media (coir peat 60% + 40% perlite;
v/v). Nutrient solution, containing all the macro- and
micro-nutrients (N-128, P-58, K-211, Mg-40, Ca-104,
S-54, Fe-5, Zn-0.25, B-0.7, Mn-2.0, Cu-0.07, Mo-0.05
ppm each) formulated in our laboratory for strawberry
cultivation was supplied to each pot at the rate of 8 l
h-1 discharge capacity through microtubes from lateral
lines using an automated drip irrigation system. During
day time, the timer was adjusted to supply nutrient
solution for 15 min. at every 3 h interval from a 400 l
capacity plastic tank.
Response of strawberry cv. Festival grown under vertical soilless culture
system
B.N.S. Murthy*, F. Karimi**, R.H. Laxman*** and V.S.J. Sunoj***
Division of Fruit Crops, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bengaluru 560 089
ABSTRACT
Strawberry is being promoted for year round production due to its highly desirable taste, avour and health
properties, and it is possible through soilless cultivation. A study on production of strawberry cv. Festival under
vertical growth system with four tiers on soilless medium in a passively ventilated greenhouse was attempted.
Signicant differences were observed for the growth parameters, viz., number of leaves, leaf area, crown diameter
and biomass production. Of the four tiers, rst tier planting tended to show the enhanced plant growth and
photosynthesis rate with early owering, higher fruit yield of improved fruit quality than lower tiers tested.
Key words: Growth, strawberry, photosynthesis, fruit quality, vertical farming, yield.
Short communication
*Corresponding author’s E-mail: bnsmurthy@iihr.ernet.in
**Faculty of Agriculture, Alberoni University, Afghanistan
***Division of Plant Physiology and Biochemistry, ICAR-IIHR, Hessaraghatta,
Bengaluru 560 089.
DOI : 10.5958/0974-0112.2016.00066.9
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301
Response of Strawberry Grown under Vertical Soilless Culture
Leaf characteristics like petiole length, number of
leaves and leaf area were recorded at 160 days after
planting (DAP). Total leaf area per plant was measured
at 160 DAP using leaf area meter (LI 3100, LI-COR,
USA). Growth parameters such as crown diameter,
shoot and root fresh and dry weights were recorded
at 160 DAP. The dry weights were obtained after
drying the samples in oven at 80ºC. Time taken for
the rst owering in plants was recorded as and when
owering occurred in each treatment. Total numbers
of owers, total number of fruits, total fruit weight,
percent marketable fruits, average fruit size (length
and diameter) were recorded at appropriate times.
The fruit total soluble solids (TSS) were determined
by using hand refractometer (Erma Ltd. Japan). The
values were corrected at 25ºC and expressed as °Brix.
Titratable acidity was determined by macerating 10 g
of fruit sample in distilled water. The pulp was ltered
through muslin cloth and made up to 10 ml with
distilled water and 5 ml of ltrate was titrated against
standard NaOH using phenolphthalein indicator. The
value was expressed in terms of malic acid as per cent
titratable acidity (Anon, 2). The observations on gas
exchange characteristics were recorded by portable
photosynthesis system LC pro (ADC Bioscientic Ltd.
UK) as ambient light between 9300 to 1100 h at 120
DAP. Availability of PAR in each Verti-Gro system tier
was measured with quantum sensor present in the leaf
chamber of portable photosynthesis system.
Strawberry plants grown at different Vertical growth
system tiers showed signicant differences in growth
parameters. At 160 DAP, highest petiole length was
observed in plants grown in fourth tier and lowest in rst
tier (Table 1). The progressive reduction in PAR from
rst to fourth tier (Table 2) could have inuenced petiole
length in lower tiers. In strawberry, low light intensity
resulted in formation of longer petiole. Signicantly
higher number of leaves and maximum leaf area was
observed in the rst tier and it gradually decreased
down with the tiers and lowest number of leaves and
leaf area was observed in the fourth tier. Higher leaf
area per plant was due to higher number of leaves
per plant in rst tier. High irradiance was necessary to
increase leaf area of strawberry (Ceulemans et al., 4)
and the higher number of leaves directly contributes
to the increase in leaf area (Jagadeesh, 6).
The observations on gas exchange characteristics
recorded at 120 DAP, showed the maximum
photosynthesis rate (3.75 µmol CO2m-2 s-1) in the
rst tier and minimum (1.68 µmol CO2 m-2 s-1) in the
fourth tier. This could be attributed to maximum PAR
incidence on leaf surface of the plants grown in rst
tier which markedly declined in lower tiers. In the rst
tier, highest PAR of 146.66 µmol m-2 s-1 was available
at 120 DAP. In Verti-Gro system, Takeda (9) observed
Table 1. Leaf characteristics of strawberry cv. Festival
grown at 160 DAP in different tiers under vertical soilless
culture system.
Tier position Petiole
length (cm)
Av. No. of
leaves plant-1
Leaf area
(cm2 plant-1)
Tier 1 11.03c39.00a2002.64a
Tier 2 11.03c37.08a1884.75b
Tier 3 12.91b34.33b1775.50c
Tier 4 13.75a32.16c1614.08d
CD at 5% 0.74 2.08 76.91
NS = Non-signicant; Means followed by different letters in a
column indicate signicant difference at p 0.05 according to
Duncan’s multiple-range test.
Table 2. Net photosynthesis rate (pN), stomatal conductance
(gs), transpiration rate (e) and available photosynthetic
active radiation (PAR) at 120 SAP in the different tier
positions.
Tier
position
PN (µmol
CO2 m-2 s-1)
gs (µmol
m-2 s-1)
E (µmol
m-2 s-1)
PAR (µmol
m-2 s-1)
Tier 1 3.75a0.09a3.36a146.7a
Tier 2 1.82b0.09a2.89a120.0b
Tier 3 1.66b0.09a2.99a93.00c
Tier 4 1.68b0.08a2.93a74.70c
CD at 5% 1.37 NS NS 17.06
NS = Non signicant; Means followed by the different letter in a
column indicates signicant difference at p 0.05 according to
Duncan’s multiple-range test.
the irradiance reaching the plants at the bottom of the
column was only 10% of the levels measured at top due
to shading effect of upper tiers. Hence, light intensity
and its distribution are the limiting factors with the
present technique Verti-Gro system (Villiers, 11). The
transpiration rate and stomatal conductance were not
affected by tier position in the Verti-Gro system (Table
2). The reasons could be due to uniform temperature
and humidity inside the greenhouse at the time of
recording gas exchange observations.
The plant growth and development at different tiers
of the Vertical growth system was also signicantly
inuenced. Highest crown diameter was recorded
in the rst tier and lowest in the fourth tier (Table 3).
Takeda (9) earlier reported, production of smaller
strawberry crown at the lower section in Verti-Gro
system due to low light availability. Shoot and root fresh
and dry weights were also highest in the rst tier and
lowest in fourth tier (Table 3). The higher biomass in
shoot and root was due to higher photosynthesis rate
and leaf area per plant observed in the rst tier. The
strawberry cv. Camarosa grown in smaller column size
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Indian Journal of Horticulture, June 2016
(6 pots/ column) of Verti-Gro system produced higher
shoot fresh weight as compared to plants grown in
bigger column size (8 pots/ column), with decreased
light penetration in lower section of the Verti-Gro
system (Al-Raisy et al., 1).
Availability of PAR, total leaf area per plant,
photosynthesis rate and biomass significantly
inuenced the days taken for ower initiation among
the tiers. Plants in rst tier took least number of days
for ower initiation and highest number of days was
required for plants in fourth tier (Table 4). In cv. Chandler
the ower initiation in plants cultivated at the top of the
Verti-Gro column was 17 days earlier than middle tier
and 37 days earlier than bottom tier (Takeda, 15).
Tier position signicantly inuenced the total number
of owers per plant, highest being in the rst tier and
lowest in the fourth tier. In cv. Geneva light intensity
of 430 μmol m-2 s-1, almost doubled the number of
owers per plant compared to 220 μmol m-2 s-1 (Dennis
et al., 5). In the present study also the shading effect
of upper tiers caused low PAR availability in the lower
tiers and consequent reduction in photosynthesis rate,
leaf area and biomass, which resulted in the reduction
in number of owers. Maximum number of fruits was
obtained in the rst tier and minimum in the fourth tier.
Due to low light, strawberry plants grown in middle
and bottom tier did not develop optimal branch crowns
and subsequently produced less number of fruits as
compared to plants in the top tier (Takeda, 9).
The position of tier also had signicant inuence
on average fruit weight. Plants in rst tier produced
signicantly higher fruit weight as compared to other
tiers and the lowest fruit weight was recorded in
the fourth tier (Table 4). The gain in average fruit
weight could be attributed to higher photosynthesis
rate recorded in the rst tier, which provided higher
photosynthates to the developing fruits, thus increasing
individual fruit weight. The cv. Chandler under higher
light intensity produced larger fruits as compared to
low light intensity (Villiers, 11).
The fruits produced in the first tier were of
high quality with significantly higher length and
diameter, total soluble solids (TSS), lower titratable
acidity compared those produced on lower tiers
(Table 4). The better quality fruits could be due to
higher photosynthates available to the developing
fruits in the rst tier as higher light availability caused
higher photosynthesis rate. In strawberry, fruit TSS
ranged from 5 to 8°Brix at different sections of Verti-
Gro system and it increased as the light intensity
increased (Vasilakakis et al., 10). High TSS content in
strawberry fruits was strongly related to the leaf: fruit
ratio (Carlen et al., 3). Hence, for maximum utilization
of the growing site, Vertical growth system is found
to be the best option for commercial production as
well as home gardening. Among the four tiers of
the vertical growth system, signicant differences
were observed in growth parameters mainly due to
differences in PAR availability. Higher PAR availability
resulted in higher photosynthesis rate and better
growth of the plants in the rst tier. Thereby leading to
early owering, higher number of owers, fruits, total
Table 3. Fresh and dry biomass and crown diameter of
strawberry cv. Festival grown at 160 DAP in different tiers
under vertical soilless culture system.
Tier
position
Shoot
fr. wt.
(g)
Shoot
dry wt.
(g)
Root
fr. wt.
(g)
Root
dry wt.
(g)
Crown
dia.
(mm)
Tier 1 55.34a15.41a17.27a4.41a31.00a
Tier 2 53.44a13.73b16.56a4.01ab 29.58a
Tier 3 47.96b13.42c14.65b3.55bc 26.33b
Tier 4 46.05b12.69c13.12c3.28c25.83b
CD at 5% 3.55 0.91 1.11 0.55 3.08
Means followed by different letters in a column indicate signicant
difference at p ≤ 0.05 according to Duncan’s multiple-range test.
Table 4. Days to ower initiation, yield characteristics and fruit quality of strawberry cv. Festival under vertical soilless
culture system.
Tier
position
Days
taken for
ower
initiation
Total
No.
owers
plant-1
Total
No. of
fruits
plant-1
Total fruit
weight
plant-1
(g)
Av. fruit
wt. (g)
Av. fruit
length
(mm)
Av. fruit
dia.
(mm)
Marketable
fruits (%)
Total
soluble
solids
(˚B)
Titratable
acidity
(%)
Tier 1 57c29a18a195a11.47a30.75a26.25a68.33a10.51a0.81c
Tier 2 60b25b14b145b10.64a28.25a25.91a60.50b10.15a0.83bc
Tier 3 60b24b14b140b10.55a28.08b25.50a59.41b9.62b0.91c
Tier 4 65a21c13b102c8.02b25.83c22.08b49.08c8.44c1.04a
CD at 5% 2.62 1.97 2.16 29.9 1.92 1.52 1.04 6.21 0.49 0.09
Means followed by the different letter in a column indicates signicant difference at p ≤ 0.05 according to Duncan’s multiple-range test.
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303
Response of Strawberry Grown under Vertical Soilless Culture
fruit weight, average fruit weight and better quality
fruits compared to other lower tiers.
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... One way to increase the space utilization efficiency is to increase the planting density. Several arrangements have been tested on different species, for example on tomato (Méndez-Galicia et al., 2005), on different flowers, including rose, zinnia, snapdragon, bachelor button, angelonia, salvia, godetia, and chrysanthemum (Anderson, 2008), on lettuce (Touliatos et al., 2016), and on strawberries (Linsley-Noakes et al., 2006;Murthy et al., 2016). ...
... Table 1 shows PPFD data for the treatments. Murthy and coworkers reported the same pattern of photosynthetically active radiation (PAR) between upper and lower levels in a 172-cm-tall column of strawberry crops arranged over four levels, in which the lowest level received 50.9% less PAR compared with the upper level (Murthy et al., 2016). In an experiment with lettuce crops, the light intensity decreased significantly from top to bottom of vertical columns within a vertical farming system: PPFD values varied between 491 and 134 µmol m -2 s -1 between the top and bottom of the column (Touliatos et al., 2016). ...
... The best yield was obtained in L4 of the columnar system (V5), while in levels L2 and L3 of all systems there were medium yields. Similar results have seen reported by Murthy et al. (2016), who found that the yield of the bottom level was 52% of that of the upper level, and was also lower than the yield of the middle level. In our experiment, the number of fruits per plant in the systems was 20.11, 24.63, and 20.68 for H3, H5, and V5 respectively. ...
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Space utilization is very important in greenhouse production systems, and particularly for small crops such as strawberries. An experiment was carried out to evaluate phenology, yield and quality of strawberry under three high-density hydroponic settings. These systems were: 1) three-level horizontal PVC pipes (H3), 2) five-level horizontal polyethylene gutters (H5) and 3) vertical bucket columns (V5). These systems were established with densities of 17.7, 29.4 and 49.1 plants∙m-2, respectively. The strawberry crop Fragaria × ananassa Duch. 'Festival' was grown in a greenhouse with polyethylene covering at Chapingo University, Mexico. An experimental setting was established with a completely randomized design with four replications for each system. The crop was grown in a coconut fiber substrate, and the nutrient solution was fed with an electrical conductivity of 1.3 mS cm-1 during the first 45 days after plantation; thereafter, it was adjusted to 2.0 mS cm-1. The pH was kept between 5.5 and 6. Climate data such as ambient temperature and relative humidity were recorded at 5-min intervals. The plant variables evaluated included flowers, clusters, crowns, leaves, number of fruits and yield. Fruit samples were selected at each level for all the systems. The total soluble solids of the fruits at each level was also evaluated. The yield was better in system V5 than in systems H3 and H5. In the upper levels of the systems (H3, H5 and V5), total soluble solids were higher. More leaves appeared in the H3 and H5 systems than in the V5 system. https://doi.org/10.17660/ActaHortic.2018.1227.41
... Furthermore, in the second season, the largest number of leaves was recorded using the tower aeroponic system and MWL 3 (number of leaves = 36), with a 56.5% increase above the control (Table S1). The number of leaves was lower than that reported by Murthy, et al. [44], who found that strawberries had a greater leaf number when grown in soilless culture on a vertical system. However, our findings were better than those of Youssef and Abou kamer [45], who found that using a magnetic field to treat the nutritional solution increased the number of plant leaves by just 27%. ...
... Correia, et al. [53] showed that the maximum fruit weight per strawberry plant was 172 g and 132 g for 'Ventana and Candonga' strawberry in hydroponic systems. Murthy, et al. [44] reported that the maximum total fruit weight per plant was 195 g when they compared tiers of vertical soilless culture. Our study values were higher than the total fruit weight per plant reported by Talukder, et al. [54], where it was 225 g. ...
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... Gradients of temperature, light and other factors (Jarvis, 1992) across the different growing levels may result in unwanted crop variability. A study of a soilless four tier strawberry (Fragaria spp.) glasshouse system found significant differences in a number of growth parameters between levels, with plants on the top tier showing higher yield and quality than those on lower levels, thought to be due to the greater availability of photosynthetically active radiation (PAR, Murthy, Karimi, Laxman, & Sunoj, 2016). In glasshouse-based systems, to attempt to ensure that each level of the stacked system receives an equal share of light, supplementary artificial lighting or a rotating mechanism that moves each level in turn to the top of the stack can be used to reduce shading of lower levels and maintain homogeneity of growing conditions for each level (Massa et al., 2008;Morrow, 2008). ...
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Effects of Column Sizes and Media on Yield and Fruit Quality of Strawberry Under Hydroponic Vertical System AUTHOR(S) Al-Raisy, Fatma S.; Al-Said, Fahad A.; Al-Rawahi, Muthier S.; Khan, Iqrar A.; Al-Makhmari, Salim M.; Khan, M. Mumtaz PUB. DATE June 2010 SOURCE European Journal of Scientific Research;Jun2010, Vol. 43 Issue 1, p48 SOURCE TYPE Academic Journal DOC. TYPE Article ABSTRACT Studies were carried out to observe strawberry response to four growing substrates under a vertical hydroponics system under non-cooled shade house conditions during winter season at Rumais, Oman. The productivity response of strawberry was assessed in respect to biomass indices, yield, quality and ionic concentration attributes. The results indicated that column types had a significant effect on most of the characters studied; growing substrate also showed significant effects on some characters while there was a significant interaction with respect to fresh shoot weight and fruit juice pH. Among the column types, columns with 6-pots performed significantly better than others in terms of biomass yield and fruit quality attributes. Among the growth media, a mixture of perlite and peat moss irrespective of their ratios showed significant superiority compared to the mixture of perlite and local plant fibre. It can be concluded that vertical hydroponics systems could be used for cultivation of strawberry in 6-pot columns with peat moss or local peat. However, the use of local plant fibre (shredded date leaf bases) is recommended because of cost and availability. The results demonstrated that strawberries could be produced under non-cooled shade-house conditions in Oman with fruit yields of 8-10 kg/m� comparable to yields obtained else where.
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The effects of supplemental irradiation in the greenhouse with high intensity discharge (HID) lamps and the interaction with the nutrient film technique (NFT)-gutter position on gas exchange processes, plant morphological characteristics (such as length of leaf petiole, total leaf area, number of flowers) and yield of forced strawberry plants were studied. Length of flower stalk, length of leaf petiole and total leaf area were significantly increased under supplemental irradiation. Net CO2 gas exchange rates, measured both in the laboratory and under glasshouse conditions were also significantly influenced by adding supplemental irradiation. Net CO2 gas exchange rates of non-irradiated control plants under glasshouse conditions were higher than those under supplemental irradiation. However, supplemental HID irradiation put the strawberry plant higher on its CO2-exchange—PPFD response curve, which resulted in increased CO2-uptake. Raised gutters influenced the lower (broader) gutters negatively and slightly decreased strawberry productivity. Although HID supplements increased earliness by 10–14 days, cumulative strawberry yield was not significantly altered. This resulted in a significant improvement of economic yield for supplementary irradiated strawberry plants.
Article
The use of hydroponic strawberry production systems is increasing worldwide. Although higher planting densities are possible in vertical production systems, these higher planting densities may have a negative effect on individual plant yield and fruit quality due to lower light levels when compared to conventional (horizontal) production systems. Optimum planting densities will for this reason be affected by light intensities inside the greenhouse and configuration of the vertical production systems. Two experiments were conducted in a plastic cladded greenhouse, fitted with a wetwall and fan cooling system, at the Department of Agronomy, University of Stellenbosch, South Africa during the period of April 2007 to November 2007 (late autumn to early summer). Mean daily maximum temperatures exceeded 26 oC during most of the 14 week harvest period (22 August to 30 November 2007), while photosynthetic active radiation (PAR), measured at 12h00 on cloudless days, inside the greenhouse increased from about 200 μMol m-2 s-1 to about 460 μMol m-2 s-1 during this period. The first experiment compared the effect of two vertical production systems (vertical system and ‘A-shape’ system), subjected to different planting density (16.7, 23.3 and 33.3 plants m-2) and shading (0%, 20%, 50%) treatments, as measured on selected yield, quality and growth factors. The second experiment studied the effect of different planting density (3.3, 5.6 and 10 plants m-2) and shading (0%, 20%, 50%) treatments on the same yield, quality and growth factors in a conventional production system. A comparison with regard to these factors was also made between the highest planting densities of the conventional-, vertical- and ‘A-shape’ system. Thesis (MScAgric (Agronomy)--University of Stellenbosch, 2008.
Effect of substrate (new or used perlite), plant orientation on the column and irrigation frequency on strawberry plant productivity and fruit quality
  • M Vasilakakis
  • A Alexandridis
  • S El Fedl
  • K Anagnostou
Vasilakakis, M., Alexandridis, A., El Fedl, S. and Anagnostou, K. 2005. Effect of substrate (new or used perlite), plant orientation on the column and irrigation frequency on strawberry plant productivity and fruit quality. Cahiers Options Mediterra. 31: 357-63.
Determination of titratable acidity. IFU-Analysis Nr.3. International Federation of Fruit Juice Producers (IFU)
  • Anonymous
Anonymous, 1996. Determination of titratable acidity. IFU-Analysis Nr.3. International Federation of Fruit Juice Producers (IFU), Paris.