© The Authors, 2023, Published by the Universidad del Zulia*Corresponding author: jconde@utmachala.edu.ec
Keywords:
Non-erosive ow
Subsurface irrigation
Lack of water
Slope of the furrows
Water productivity using furrow and drip irrigation in hybrid maize
Productividad del agua empleando riego por surcos y goteo en maíz híbrido
Produtividade de água usando Irrigação por sulco e gotejamento em milho híbrido
José Lauro Conde Solano*
Sara Enid Castillo Herrera
Leonor Margarita Rivera Intriago
Paola Alicia Gálvez Palomeque
Rev. Fac. Agron. (LUZ). 2023, 40(3): e234024
ISSN 2477-9407
DOI: https://doi.org/10.47280/RevFacAgron(LUZ).v40.n3.02
Crop production
Associate editor: Dr. Jorge Vilchez-Perozo
University of Zulia
Faculty of Agronomy
Bolivarian Republic of Venezuela
Universidad Técnica de Machala - Ecuador, Facultad
de Ciencias Agropecuarias, Grupo de Investigaciones
Multidisciplinario (GIM). Machala, Ecuador.
Received: 17-05-2023
Accepted: 13-06-2023
Published: 01-07-2023
Abstract
Agriculture is the economic sector that consumes around 70 % of the total
water extracted globally, considering itself a victim of its own ineciency.
The present work was oriented to look for irrigation alternatives that allow
a greater productivity of water. The trial was carried out at the Faculty of
Agricultural Sciences, Technical University of Machala, Ecuador. The
amount of water applied to the corn crop through furrow and drip irrigation
was evaluated. The treatments were: furrow irrigation, supercial drip
irrigation and subsurface drip irrigation at 20 cm. The trial had a surface
area of 450 m
2
, in a completely randomized block experimental design with
three treatments and three repetitions. The control of the irrigation regime
was carried out through tensiometers installed for each treatment. The
volume of water applied and the dry grain yield in irrigation by furrows
was 3,484 m
3
.ha
-1
and 9,175 kg.ha
-1
, for surface drip irrigation of 1,452
m
3
.ha
-1
and 10,200 kg.ha
-1
, and for subsurface drip irrigation it was 1,237
m
3
.ha
-1
and 10,181.2 kg.ha
-1
. The water productivity for the furrow irrigation
treatment was 2.63 kg.m
-3
, for surface drip irrigation it was 7.02 kg.m
-3
and
for subsurface drip irrigation at 20 cm it was 8.23 kg.m
-3
being the highest
productivity.
This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.
Rev. Fac. Agron. (LUZ). 2023, 40(3): e234024. July-September. ISSN 2477-9407.
2-5 |
Resumen
La agricultura, es el sector económico que consume alrededor
del 70 % del total de agua extraída en forma global, considerándose
víctima de su propia inecacia. El presente trabajo se orientó a buscar
alternativas de riego que permitan una mayor productividad del
agua. El ensayo se realizó en la Facultad de Ciencias Agropecuarias,
Universidad Técnica de Machala, Ecuador. Se evaluó la cantidad de
agua aplicada al cultivo de maíz a través del riego por surcos y goteo,
Los tratamientos fueron: Riego por surcos, riego por goteo supercial
y riego por goteo subsupercial a 20 cm. El ensayo tuvo una supercie
de 450 m
2
, en un diseño experimental de bloques completamente al
azar con tres tratamientos y tres repeticiones. El control del régimen
de riego se realizó a través de tensiómetros instalados para cada
tratamiento. El volumen de agua aplicado y el rendimiento en grano
seco en el riego por surcos fue 3.484 m
3
.ha
-1
y 9.175 kg.ha
-1
, para el
riego por goteo supercial de 1.452 m
3
.ha
-1
y 10.200 kg.ha
-1
, y para el
riego por goteo subsupercial fue 1.237 m
3
.ha
-1
y 10.181,2 kg.ha
-1
. La
productividad del agua para el tratamiento riego por surcos fue 2,63
kg.m
-3
, para el riego por goteo supercial fue de 7,02 kg.m
-3
y para el
riego por goteo subsupercial a 20 cm de 8,23 kg.m
-3
siendo la mayor
productividad.
Palabras clave: caudal no erosivo, riego subsupercial, escasez de
agua, pendiente de los surcos
Resumo
A agricultura é o sector económico que consomé cerca de 70 %
do total de agua extraída globalmente, considerando-se vítima de
sua própria ineciência. O presente trabalho foi orientado a buscar
alterntivas de irrigação que permitam uma maior produtividade
de água. O experimento foi realizado na Facultade de Ciências
Agrárias. Universidade Ténica de Machala, Equador. Avaliou-se a
quantidade de água aplicada na cultura domilho por meio de irrigação
por sulco e gotejamento, sendo os tratamentos: irrigação por sulco,
irrigação por gotejamento supercial e irrigação por gotejamento
subsupercial a 20 cm. O ensaio teve uma área de supercie de 450
m2, en delineamento experimental em blocos casualizados com três
tratamentos e três repetições. O controle do regime de irrigação foi
realizado por meio de tensiómetros instalados para cada tratamento.
O volume de água aplicado e o rendimento de grãos secos na irrigação
por sulcos foi de 3.484 m
3
.ha
-1
e 9.175 kg.ha
-1
, para gotejamento
supercial de 1.452 m
3
.ha
-1
e 10.200 kg.ha
-1
, e para irrigação por
gotejamento subsuperciall foi de 1.237 m
3
.ha
-1
e 10.181,2 kg.ha
-1
.
A produtividade de água para o tratamento de irrigação por sulco foi
de 2,63 kg.m
-3
, para irrigação por gotejamento supercial foi de 7,02
kg.m
-3
e para irrigação por gotejamento subsupercial a 20 cm foi
8,23 kg.m
-3
sendo a maior produtividade.
Palavras-chave: uxo não erosivo, Irrigação subsupercial, falta de
água, inclinação dos sulcos
Introduction
Water is the main element of all living organisms. In plants, it
represents 80 to 90 % of the fresh weight in herbaceous plants and
more than 50 % in woody plants (Alarcón, 2020), becoming the
main means of transport of nutrients from the soil. Although water
is the main element of the plant, the major consumption of this
element is not in the formation of plant tissues, but in the process of
evapotranspiration, considering that in most crops evapotranspiration
represents more than 95 % of water consumption.
The water consumed by plants is that used during phenological
phases, characterized by crop evapotranspiration (Siebert and Döll,
2010). Although agriculture consumes the largest amount of water
withdrawn, however, 44 % of agricultural production is obtained in
irrigated areas, representing only 18 % of the cultivated area (FAO,
2019). From an environmental point of view, the concept of water
footprint is an established means of determining water consumption
to obtain a given product, it is not eective in describing the impact of
agricultural practices on water availability and scarcity in a particular
region (Jeswani and Azapagic, 2011). Humanity must produce more
food with less water, aiming to improve the eciency of irrigation
water use.
The optimization of water use, should be the main concern of
those who plan its use for irrigation, water is an irreplaceable strategic
resource that becomes the dynamizing axis of the agricultural sector
through irrigation, in Ecuador irrigated production contributes 70
% of national agricultural production (SENAGUA, 2016). Ecient
irrigation is water that properly moistens the root zone, therefore, the
amount of water incorporated into the soil must correspond to the
water consumed by the crop.
Irrigation has been applied by dierent methods and techniques,
thus the most used by agricultural sectors is gravity or surface irrigation,
which represents approximately 75 %, while sprinkler irrigation
and high frequency localized irrigation (drip and micro-sprinkler)
represent 25 % of the total irrigated area globally (FAO, 2019). In
Ecuador, the area irrigated by gravity or surface is approximately 56
%, and for sprinkler, micro-sprinkler and drip irrigation it is 43 % of
the total irrigated area (SENAGUA, 2019).
In gravity or surface irrigation, furrows and ridges have variable
and decreasing ow rates due to the inltration of water into the soil
during its course, which supplies small ows from the highest to the
lowest elevation, following the slope, preferably from 0.2 to 0.5 %
(Fuentes, 2002). The length of the furrows is variable because it is
a function of soil texture, slope, and soil depth. The soil is wetted
by water inltration through the wetted perimeter of small channels.
Because they are spaced, the water partially covers the soil between
furrows and is wetted by the eect of the advance of moisture in depth
and laterally, the separation of the furrows ranges from 0.30 m to 1.20
m, depending especially on the texture and the crop.
The ow rate supplied to the furrows is a function of the furrow
slope and soil texture and is called “maximum non-erosive ow rate”
which is calculated with the following mathematical expression:
Where: Qmax. Represents maximum non-erosive ow (L.s
-1
);
“S” the slope in percentage; C = 0.57 for sandy soils; C = 0.63 for
loamy soils; and C = 0.96 for clay soils (Gurovich, 1985).
Drip irrigation is an alternative designed to improve water
productivity in agriculture, in the case of surface drip irrigation
water evaporation decreases signicantly, because the wet surface of
the soil is small, and in subsurface drip irrigation it is not in direct
contact with solar radiation, reducing water losses by soil evaporation
(Irmak et al., 2016). Most of the water applied through irrigation
methods, both in surface irrigation systems (furrows, beds, ood) and
This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.
Conde et al. Rev. Fac. Agron. (LUZ). 2023 40(3): e234024
3-5 |
sprinkling is lost by evaporation, considering that much of this water
consumption is not useful for the plant (non-benecial consumption).
Kafka and Tarchitzky (2012) state that drip irrigation allows
direct delivery of water to the plant with minimal water losses by
evaporation from the soil not covered by the plants. Martinez and
Reca (2014) found a 20 % dierence in favor of subsurface irrigation
compared to surface irrigation; Lucero-Vega et al. (2017) determined
that water loss by evaporation in subsurface irrigation was lower by
44 % with respect to surface drip irrigation.
The similarity between the furrow irrigation method and the drip
irrigation method is that the crop takes the same amount of water
for its physiological functioning irrigated with the two methods, and
the dierence is that dierent amounts of water are applied with
particular characteristics of each irrigation method. The objective
of this research was to evaluate the productivity of irrigation water
applied by furrows, surface drip and subsurface drip in hybrid corn.
Materials and Methods
The research was carried out at the Facultad de Ciencias
Agropecuarias, Universidad Técnica de Machala - Ecuador, whose
geographical location is at coordinates 620000 W and 9638000 S
and 620200 W and 9637800 S, geographical zone 17 S, universal
transverse mercator projection.
The climate of the area where the project was developed is
classied as tropical megathermal semi-humid, it is located at 5 masl,
with an average temperature of 25 °C, the average rainfall is 600 mm
with dened pluviometric periods, the rainy period usually begins in
January and ends in April, the dry period begins in May and ends in
December, the annual reference evapotranspiration is between 1300
to 1500 mm.year
-1
, greater than rainfall, resulting in a signicant
water decit (Plan de Desarrollo y Ordenamiento Territorial de la
Provincia de El Oro, 2015). The soil is silt loam in the rst 30 cm of
depth, at greater depths the soils are generally sandy. The proportions
of mineral material were: sand 34.24 %, silt 63.82 % and clay 1.94 %
(Villaseñor et al., 2015).
The recording of the information began with the sowing of the seed
on August 20, 2022, the corn seed used was DASS 3383 sown at 80
cm between rows and 40 cm between plants, with two seeds per hole,
giving a planting density of 62,500 plants.ha
-1
. The experiment was
designed as a totally randomized block design with three treatments
and three replications. The treatments were: furrow irrigation (T1),
surface drip irrigation (T2), and subsurface drip irrigation at 20 cm
(T3), with three replications. The experimental area was 450 m
2
, the
experimental unit was a 50 m
2
plot, and the last irrigation was applied
after 100 days.
The irrigation system was designed so that each treatment
is irrigated independently, with its respective piping system and
control system (gate valves), installed before planting the seed.
The accounting of the volume of water applied per irrigation and
total accumulated during the crop cycle was done with precision
volumetric valves. Regarding irrigation management, the frequencies
or intervals of irrigation supply, as well as irrigation times were
considered according to the readings of tensiometers (irrometer
®
model), which were installed at 20 cm depth, where the highest
percentage of the plant’s root mass is located. The discharge of the
emitters (drippers) was 1.65 L.h
-1
, with a variation of 5 % of the
dripper discharge, the working pressure was 10 mH
2
O (Hydrodrip
Super Flat Integral Dripline, PLASTRO). The irrigation laterals were
installed at 80 cm and 50 cm from the emitters (drippers) respectively.
The irrigation laterals were 16 mm diameter hydrodrip tape, the
secondary conduction was 32 mm polyethylene hose, while the main
conduction was 40 mm external diameter PVC pipe. The furrows
were 10 m long, with a slope of 0.5 % and the ow supplied was 1
L.s
-1
. The energy source that fed the irrigation system was an electric
pump supplied from a subway well located in the trial area.
To determine the optimum irrigation moment, previously
calibrated tensiometers were installed in the area where the trial
was developed, irrigation started when the tensiometers marked 45
cbar, in the tension-humidity curve it represented 20 % moisture, and
irrigation was suspended at 10 cbar, in the tension-humidity curve it
represented 32 % moisture content (water), indicating at that moment
that the soil moisture was at eld capacity, which is the optimum
moisture point for the plants.
The dry grain yield of the crop was determined from 5 plants per
experimental unit totaling 15 plants analyzed per treatment, whose
values were processed through the Statistical Analysis System (SAS)
software for their respective analysis. The irrigation eciencies
known for the dierent irrigation methods have been replaced by
an indicator that expresses water productivity in terms of yield,
proposed by Droogers and Kite (1999), which in this research was
used to measure or determine the economic index of the water used
for irrigation (irrigation water productivity), in a given crop, whose
mathematical expression is as follows:
Results and discussion
The amount of water supplied is a function of the crop and the
dierent methods of water application for irrigation, showing the
results in terms of water productivity kg.m
-3
through furrow irrigation,
surface drip irrigation and subsurface drip irrigation at 20 cm.
Regarding the number of irrigations, in the furrow irrigation
treatment 17 irrigations were applied, for the surface drip irrigation
treatment 30 were applied, and for subsurface drip irrigation 26
(gure 1, table 1), irrigation was applied up to 100 dap. It is worth
mentioning that Guevara et al. (2005) applied 32 irrigations with
subsurface drip irrigation buried 30 cm in corn. The furrow irrigation
treatment registered a lower irrigation frequency of 6 days, while
the surface drip irrigation treatment registered a higher irrigation
frequency of 3 days, and the subsurface drip irrigation treatment of 4
days (table 1).
Although the furrow irrigation treatment registered less frequency
and fewer irrigations, the volume applied was approximately 2.4 times
and 2.8 times greater than the surface drip irrigation and subsurface
drip irrigation treatments at 20 cm, respectively. This dierence in
volume of water applied means that the amount of water that is not
benecial to the plant is greater in the furrow irrigation than in the
surface and subsurface drip irrigation. Emphasizing that the water
lost by evaporation is non-benecial consumption for the plant.
With regard to the amount of water applied, the results indicated
signicant statistical dierences at (p>0.05) for the amount of water
(mm) supplied by irrigation between the furrow irrigated treatment
and those irrigated by surface drip and subsurface drip, by eect of
the treatments; the amount of water supplied by irrigation was 20.5
mm.irrigation
-1
for furrow irrigation; 4.84 mm.irrigation
-1
for surface
drip and 4.75 mm.irrigation
-1
for subsurface drip, respectively (table 2).
This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.
Rev. Fac. Agron. (LUZ). 2023, 40(3): e234024. July-September. ISSN 2477-9407.
4-5 |
Figure 1. Water sheet and number of irrigations applied in hybrid
maize: furrow irrigation (u), Surface drip irrigation
(n) subsurface drip irrigation (p).
Table 1. Frequency and number of irrigations applied to maize
(Zea mays L.).
Furrow
irrigation
Surface drip
irrigation
Sub-surface
drip irrigation
(20 cm)
Frequency of irrigation (days) 6 3 4
Number of irrigations 17 30 26
The treatments irrigated by surface drip and subsurface drip
irrigation did not show signicant statistical dierences, although the
lowest amount of water applied was for the subsurface drip irrigation
treatment at 20 cm, which was 4.75 mm.irrigation
-1
.
Table 2. Applied water (mm) per irrigation and accumulated,
through furrow irrigation, surface drip and subsurface
drip, in corn (Zea mays L.).
Water sheet
(mm)
Furrow
irrigation
Surface drip
irrigation
Sub-surface drip
irrigation (20 cm)
By irrigation 20.5
a
4.84
b
4.75
b
Accumulated 348.5
a
145.2
b
123.7
c
a, b, c
Dierent letters in each row indicate signicant statistical dierences based on
Tukey’s multiple means test (p<0.05).
With respect to the total irrigation sheet, there were signicant
statistical dierences (p<0.001) between the furrow irrigation
treatment and the surface drip and subsurface drip irrigation
treatments, where the furrow irrigation treatment applied a sheet of
348.4 mm, while the drip irrigation treatment applied a sheet of 145.2
mm and 123.7 mm for the subsurface drip irrigation at 20 cm. There
were also statistical dierences between surface drip irrigation and
subsurface drip irrigation.
With subsurface drip irrigation at 20 cm, 36 % of the volume
applied in the furrows was applied, and 85 % of the volume applied
with surface drip irrigation. It is worth mentioning that research
conducted by Al-Ghobari and Devidar (2018) determined that
subsurface or subway irrigation systems can save water between 20
and 40 % with respect to surface irrigation systems.
In this study, the subsurface drip irrigation treatment at 20 cm
was the one with the lowest water application, 123.7 mm of water.
Research work developed by Lucero-Vega et al. (2017) determined
that water loss by evaporation was lower in subsurface or subsurface
irrigation with respect to surface drip by 44 %. This evaporative
water loss in surface drip irrigation is considered non-benecial
consumption for the plant. Research work developed by Shen et al.
(2020) found high moisture contents at depths of 0 to 40 cm, irrigated
with subsurface drip with irrigation frequencies of 4 days.
Regarding dry grain yield at a moisture content of 13 %, there
were statistical dierences (p< 0.001) between the furrow irrigated
treatment and the treatments irrigated by surface drip and subsurface
drip. Dry grain yields for the furrow irrigated treatment were 146.8
g.plant
-1
(9175 kg.ha
-1
), while for the surface drip irrigation treatment
the yield was 163.2 g.plant
-1
(10200 kg.ha
-1
), and for the subsurface
drip irrigation at 20 cm, it was 162.9 g.plant
-1
(10,181.2 kg.ha
-1
)
(table 3).
Dry grain yields for the surface drip irrigation and subsurface
drip irrigation treatments at 20 cm showed no statistical dierences
(p<0.05) for treatment eects.
Table 3. Dry grain yield (kg.ha
-1
), Volume of water applied
(m
3
.ha
-1
), and Water productivity (kg.m
-3
), applied in
furrow irrigation, surface drip irrigation, and subsurface
drip irrigation.
Treatment
Yield
(kg.ha
-1
)
Volume of
water applied
(m
3
.ha
-1
)
Water productivity
(kg.m
-3
)
Furrow irrigation
175
b
3,484
a
2.63
c
Surface drip
irrigation
10,200
a
1,452
b
7.02
b
Subsurface drip
irrigation at 20 cm
10,181.2
a
1,237
c
8.23
a
a, b, c
Dierent letters in each row indicate signicant statistical dierences based on
Tukey’s multiple means test (p<0.05).
These results coincide with the research carried out by Martínez
and Reca (2014) who obtained higher olive and oil yields with
subsurface drip irrigation with respect to surface drip irrigation,
stating that this is due to the better distribution of water in the wet
bulb. The yields obtained in this research were lower than those
obtained by Zhang et al., (2019) in Xinjian Northwest China who
obtained yields of 19.1 and 21 t.ha
-1
.
For the furrow irrigated treatment a volume of 3,484 m
3
.ha
-1
was
applied, for surface drip irrigation the volume applied was 1,452
m
3
.ha
-1
, and for subsurface drip irrigation at 20 cm of 1,237 m
3
.ha
-1
(table 3).
Regarding the volume of water applied, there were statistical
dierences (p˂0.001), between the treatment irrigated by furrows,
This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.
Conde et al. Rev. Fac. Agron. (LUZ). 2023 40(3): e234024
5-5 |
surface drip and subsurface drip at 20 cm. Likewise, the treatments
irrigated by surface drip and subsurface drip at 20 cm also presented
statistical dierences (p˂0.001), with a dierence of 15 % less water
applied for the treatment irrigated by subsurface drip at 20 cm.
Research conducted in China by Yan et al. (2016), applied water
sheets in subsurface drip irrigation at 30 cm depth of 162 mm (1,620
m
3
.ha
-1
).
Referring to water productivity, they presented statistical
dierences (p˂0.003) between the furrow irrigated treatment and
those irrigated by surface drip and subsurface drip at 20 cm, for
furrow irrigation a water productivity of 2.63 kg.m
-3
was obtained,
for surface drip irrigation water productivity was 7.02 kg.m
-3
, and
for subsurface drip irrigation at 20 cm of 8.23 kg.m
-3
. Research by
Stanghellini (2010), found that the average water productivity in the
65-country drip-irrigated maize crop was 7.0 kg.m
-3
.
Similarly, water productivity, the treatments irrigated by surface
drip and subsurface drip at 20 cm, presented statistical dierences
(p˂0.003) (table 3). Water productivity in the treatment irrigated by
subsurface drip at 20 cm, in relation to water productivity in furrow
irrigation was 3.1 times higher, and 1.2 times higher than water
productivity in surface drip irrigation.
Conclusions
The management plan for furrow, surface drip and subsurface drip
irrigation generates dierent strategies for its use and management,
by having dierent frequencies and number of irrigations. Furrow
irrigation required less frequency and fewer irrigations, in contrast to
surface and subsurface drip irrigation at 20 cm, which were applied
with a higher frequency and greater number of irrigations. The volume
of water supplied by furrow irrigation was greater than the volume
of water supplied by surface and subsurface drip irrigation systems.
Water productivity was higher with subsurface drip irrigation at 20
cm.
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