in Passive and Heated Greenhouse on Northwest of

Crop Yield and Determination of Kc
Tomato Crop (Lycopersicum
esculentum Mill.) in Passive and
Heated Greenhouse on Northwest of
Uruguay
P.Cánepa, J. Ramos, C. Saravia, N. Blanco, A.
Ferreira, R. de Souza
Water Department, CENUR Litoral Norte-Salto
Facultad de Agronomía
UDELAR
INTRODUCTION
• Over 65% of tomato production comes from
Northwest of Uruguay.
• This production is in counter-season (winter and
spring) using passive greenhouses. Farmers get
high prices at this time of year.
• Production destination is the
domestic market, mainly southern
region of the country
• the optimum temperature is 18-22 ° during the
day and 15-17 ° overnight
Introduction
• A temperature below 12 ° C slows the growth and
decay symptoms appear. Temperatures below 10
° C have negative effects on flowering, reducing
fruit set (Benacchio, 1982).
• Tomato is a summer cycle crop and does not
tolerate frost. After transplant vegetative growth
is very slow at temperatures below 10°C, as well
as flowering,completely stopping at lower
temperatures.
Temperatures in Salto °C
Means 1961-1990 serie, conventional
meteorological station
TMED-mean temperature
TX period absolute maximum temperature (monthly or annual)
TN period absolute minimum temperature (monthly or annual)
TXM maximum mean temperature
TNM minimum mean temperature
Fish farming
Passive
greenhouse
Turistic center
Thermal baths
Heated
greenhouse
Efluent hot
water
Primer re-uso
del agua termal
Segundo re-uso
del agua termal
Una vez que el agua abandona el
invernadero, aún con entalpía útil, es
conducida a través de tuberías hasta
una pileta de Peces
Objectives
• Evaluate Eto, yield, quality and precocity of
crop in heated and passive greenhouse.
• Determination of tomato Kc in greenhouse
condition
Materials and Methods
• A trial was carried out during 2013 and 2014
• Two greenhouses of 21x24 m with longitudinal
axis direction N-S. Framework of Eucalyptus
wood and coverage of PE 150μm, anti UV. Both
greenhouses placed side, elevating curtains to
allow ventilation
• One of the greenhouse was heated. Energy
source is low enthalpy geotermal from a
infrabasaltic deep well. 1.000 m depth, in Guaraní
Acquifer. Water used in heating system was at 3040° C circulating in above ground pipelines
Invernadero calefaccionado
con energía geotérmica
Energía geotermal
Heating system
Materials and Methods
• Tomato cv. Elpida (long cycle)
• Anti-aphids nets were placed in both
greenhouses.
• Chemicals were avoided, pests and diseases
control was organic due to fish farm is near.
• Crop management was similar to used by farmers
• Frost control was by sprinkler over the roof with
automatic on-off system controled by
temperature sensors
Materials and Methods
• Automatic Weather Station AWS (USB Data Logger
HOBO U30 - U30-NRC, Onset Computer Corporation,
Cape Cod, MA)were installed. Global solar radiation
and wind speed sensors, both located 1.6 m in height
and temperature sensors and humidity at 0.5, 1.0 and
1.5 m, on a pole placed between beds.
• Other automatic weather station was located outdoor
with record of temperature, humidity, wind speed,
radiation. Sensors were 1.5 m high wih records each 10
minutes
En cada invernáculo se instalaron estaciones meteorológicas automáticas (HOBO U30-NRC,
Onset Computer Corp., Cape Cod, MA) con sensores de temperatura y humedad
Materials and Methods
• Crop was irrigated by drip irrigation with fresh
water from a shalow well.
• Harvest was once a week and yield was
weighed and clasified into 4 comercial
categories at each harvest date.
Harvest
Calibración de frutos
Pesaje de frutos calibrados
Materials and Methods
• Water consumption was calculated as
difference between input of water measured
by water volume counters and output by deep
percolation measured by drainage lysimeters.
Materials and Methods
• Soil moisture was monitored by tensiometers
at 30 and 60 cm depth.
ETo was calculated using FAO Penman-Monteith
method (Allen et al, 1998). Kc was calculated
as the ratio between water consumption and
ETo.
Results 2013
• Heat balance made for both greenhouses,
assessed daily between 20:00 and 8:00, during
which solar radiation is zero, the values
presented were obtained in next table, power
supplied to the heated greenhouse (TCC),
according to Ramos et al, 2014
Power and Energy provided
Power
Electrical
Energy
equivalent
Gasoil l
Month
Maxim
Mean
Provided
Energy
Jul
7,02
2,14
753,43
793,08
123,68
Ago
6,31
1,33
493,44
519,41
81,00
Sep
4,95
0,28
100,80
106,10
16,54
l
Power [kW]
Energy [kW.h]
electrical heating with a yield
of 0.95
liters of fuel (diesel oil) needed
if a burner with performance
equal to 0.6 is used.
Power provided 2014
Month
Mean
Heating system
• The heat exchanger was sized to provide the
maximum power emissions of 9,682 kW.
However, this was not achieved because the
supply of hot water was not produced in the
appropriate hours at night.
• In 2014 the design capacity was reached and
even exceeded
• Although the temperatures in the heated
greenhouse were slightly above unheated
greenhouse, according to the ARIMA analysis,
no significant differences were found. With
regard to outdoor temperatures, the
minimum did not differ significantly from
those recorded in the greenhouses; the
maximum were higher in the protected area.
Temperatures ° C 2013
TCC heated greenhouse
T max
month
haeated
passive
exterior heated
passive
exterior
Hours with temperature equal or below 10°C
250,0
200,0
150,0
TCC
TSC
100,0
50,0
0,0
Abril
Mayo
Junio
Julio
Agosto
Setiembre
Yield 2013
heated
passive
Month of harvest
Yield 2014
Mite
attack
heated
pasive
Month of harvest
Yield
• Precocity in heated greenhouse evidenced regarding
pasive one may, in addition to energy supplied, due to
the lower number of hours that each crop was below
10 ° C (Table 8). This threshold was chosen for its effect
on flowering, decreasing the amount and viability of
the flowers when subjected to air temperatures at or
below 10 ° C (Benacchio, 1982)
• In the special category there was no significant
difference between treatments (p = 0.806). In the first
and second categories there were significant
differences in favor of heated greenhouse (p = 0.012
and p = 0.0005 respectively). In the third category
there were also no significant differences (p = 0.898).
• Changes in environmental conditions
promoted a strong attack of mites. This
happened only in the heated greenhouse.
Hours < 10°C 2014
Amount of hours
Month
% hours of month
Eto 2013
ETo 2014
ETo
• The ET0en greenhouses was lower (in a
variable percentage depending on the month
and the year in question) to the estimated
standard conditions of measurement, because
in greenhouses aerodynamic term
(responsible for the removal of water vapor
from the surface evapotranspiring) loses
importance because of the low (or no) wind
circulation.
Kc
Kc
• Kc crop coefficients were calculated as the ratio
of water consumption ( irrigation less drainage)
and reference evapotranspiration
(ET0), accumulated periods.
• These coefficients correspond to the Kcb as crop
was under mulch polyethylene.
• The Kc obtained for the whole period were 1.06
for the unheated greenhouse and 1.25 for the
heated greenhouse.
• Tomato cv. Elpida is an undeterminated cv., so all
period is flowering and fruiting.
Frost
• In 2015 valves of the autmatic on-off system
of sprinklers over the roof failed and…..
HEATED GREENHOUSE
´PASIVE GREENHOSE
conclusions
• Heated greenhouse promotes precociy of harvest
• ETo into greenhouse is less than conventional
conditions. Practically there is no wind inside the
greenhouse, so aerodinamic term of the PenmanMonteith equation becomes negligeble.
• ETo in greenhouses is about 70% of Eto in field
conditions
• First data of Kc tomato crop in greenhouse for
northwest of Uruguay was obtained
experimentally
conclusions
• Enviromental conditions ( high temperatures)
in heated greenhouse promotes attack of
Aculops lycopersici.
• Low enthalpy geotermal energy can be used
to heating greenhouse. This is a clean and free
of costs energy source.
• Thermal water can be used in sucesives
uses, including greenhouses heating, alowing
a better resource ulilization
THANKS FOR YOUR ATENTION