15
Ciencias Agrarias/ Agricultural Sciences
Revista Ciencia y Tecnología (2025) 18(1) p 15 - 22 ISSN 1390-4051; e-ISSN 1390-4043 https://doi.org/10.18779/cyt.v18i1.820
Response of trinexapac-ethyl-treated wheat to glyphosate drift
Respuesta del trigo tratado con trinexapac-etilo a la deriva de glifosato
Diecson Ruy Orsolin da Silva
1
, Rodrigo Zeni
2
, Claudir José Basso
1
1
Universidade Federal de Santa Maria, Brasil.
2
Profesional independiente, Brasil.
Autor de correspondencia: diecsonros@gmail.com
Recibido: 25/01/2024. Aceptado: 06/12/2024
Publicado el 15 de enero de 2025
Abstract
T
he herbicide drift is problem in crops when it reaches non-
target crops. The glyphosate drift after growth regulator
application can inuence in wheat response. This study
assessed the eects of glyphosate drift after trinexapac-ethyl
application on wheat. Two eld experiments were conducted
in winter season of 2018 and 2019. Cultivar TBIO Toruk and
Sossego cultivars were used in 2018 and cultivar TBIO Audaz
and Cultivar ORS Citrino in 2019. Wheat cultivars were
treated with trinexapac-ethyl followed subdoses of glyphosate
ranging from 0 to 72 g ae ha-1. The phytotoxicity from
glyphosate was less than 10% to para Cultivar TBIO Toruk
and Sossego. Glyphosate symptoms were slightly higher in
cultivar TBIO Audaz cultivar treated with trinexapac-ethyl.
The isolated eects of Trinexapac-ethyl and glyphosate
reduced plant height, but the interaction of trinexapac-ethyl
and glyphosate factors had a greater reduction on plant
height in 2019. The interaction between trinexapac-ethyl
and glyphosate promoted more damage than they alone.
Glyphosate reduced by up 11% cultivar TBIO Toruk yield
but increase around 30% to cultivar Sossego yield. Cultivar
TBIO Audaz was the most sensitive cultivar, with yield
losses of up to 59% due to glyphosate drift. Overall, the
eect of glyphosate on plant height was subdose dependent.
Subsequent application of trinexapac-ethyl to plants exposed
to the highest glyphosate subdoses resulted in decreased plant
height and dry matter accumulation. Trinexapac-ethyl has no
impact on wheat yield. The yield response was dependent of
glyphosate subdose, cultivar and year.
Keywords: growth regulator, subdose, Triticum aestivum,
yield.
Resumen
L
a deriva del herbicida es un problema en los cultivos
cuando el cultivo no alcanza su objetivo. La deriva del
glifosato después de la aplicación del regulador de crecimiento
puede inuir en la respuesta del trigo. Este estudio evaluó los
efectos de la deriva del glifosato después de la aplicación
de trinexapac-ethyl en el trigo. Se llevaron a cabo dos
experimentos de campo en la temporada de invierno de 2018
y 2019. Se utilizaron los cultivares TBIO Toruk y Sossego en
2018 y el cultivar TBIO Audaz y el cultivar ORS Citrino en
2019. Los cultivares de trigo se trataron con trinexapac-ethyl
seguido de subdosis de glifosato que variaron de 0 a 72 g ae
ha-1. La totoxicidad del glifosato fue inferior al 10% para los
cultivares TBIO Toruk y Sossego. Los síntomas del glifosato
fueron ligeramente mayores en el cultivar TBIO Audaz tratado
con trinexapac-ethyl. Los efectos aislados de Trinexapac-ethyl
y glifosato redujeron la altura de la planta, pero la interacción
de los factores trinexapac-ethyl y glifosato tuvo una mayor
reducción en la altura de la planta en 2019. La interacción
entre trinexapac-ethyl y glifosato promovió más daño que
ellos solos. El glifosato redujo hasta un 11% el rendimiento
del cultivar TBIO Toruk, pero aumentó alrededor del 30%
el rendimiento del cultivar Sossego. El cultivar TBIO Audaz
fue el cultivar más sensible, con pérdidas de rendimiento de
hasta el 59% debido a la deriva de glifosato. En general, el
efecto del glifosato en la altura de la planta dependió de la
subdosis. La aplicación posterior de trinexapac-ethyl a las
plantas expuestas a las subdosis más altas de glifosato resultó
en una disminución de la altura de la planta y la acumulación
de materia seca. Trinexapac-ethyl no tiene impacto en el
rendimiento del trigo. La respuesta del rendimiento dependió
de la subdosis de glifosato, el cultivar y el año.
Palabras clave: rregulador de crecimiento, subdosis, Triticum
aestivum, productividad.
Da Silva et al., 2025
2025. 18(1):15-22
Ciencia y Tecnología.16
Introduction
Glyphosate is one of the most widely used herbicides for weed
management in various crops, a non-selective herbicide used
to control annual and perennial weeds applied in desiccation
management and postemergence of Glyphosate-resistant crops
and widely used globally alone or in combination with others
herbicides (Almeida et al., 2015). Due to the use of glyphosate
in several crops and many times of season crop, there is always
a risk of a susceptible crop receiving glyphosate subdoses via
drifting (Duke, 2015).
Corn crops in southern Brazil can be planted from July
when it can be synchronized with wheat crop. Therefore,
the use of glyphosate for weed management in maize may
cause drift and aect wheat crops (Duke, 2015). Drift is the
movement of herbicides to a non-target area and occurs in a
combination of factors at the time of application such as wind
speed and small droplet spectrum (Perkins et al., 2022). The
production of smaller particles by inadequate tips favors the
drift and volatility of pesticides (Gandolfo et al., 2014).
Various studies have reported the damaging eects of
glyphosate drift on the development and yield of rice (McCoy
et al., 2021), maize (Brown et al., 2009), cotton (Pio de
Oliveira et al., 2021), and wheat (Davis et al., 2013; Deeds et
al., 2006; Wiersma & Durgan, 2017). However, the damages
caused by glyphosate depend on the doses and growth stage
of crop.
Simulated glyphosate drift presented severe yield loss
in wheat when applied at the node emission stage compared
to the owering stage from 84 g ae ha
-1
(Deeds et al., 2006).
Similarly, Davis et al. (2013) veried a 25% decrease in crop
yield when simulating a glyphosate drift (87 g ae ha
-1
) at the
wheat booting stage. In contrast, glyphosate subdoses up to
10 g ae ha
-1
may increase the yield of barley and white oat by
up to 12% and 30%, respectively (Belz & Duke, 2014; Silva
et al., 2020).
Most published studies involving herbicide subdoses
by studying drift or tank contamination and their eects on
crops typically test herbicide application alone. However,
under eld conditions, these herbicides may interact with
other agrochemicals applied to the crops or even the spray
tank and alter the capacity of absorption, translocation, and
metabolization of herbicides in crops. For Instance, Brown
et al. (2009) and Kelley et al. (2005) veried that applying
selective herbicides in post emergence might aggravate the
symptoms caused by the herbicide drift.
In wheat crop, growth regulators are a management
option to reduce plant height to prevent lodging (Shah et al.,
2016). Other benets are related to using growth regulators to
improve solar radiation capture by altering leaf architecture,
obtain more considerable root growth, and reduce respiration
(Chavarria et al., 2015). Also, regulators may be used as
stress-tolerating agents, as in the case of sugarcane, in which
trinexapac-ethyl increases the reactivity of the antioxidant
enzyme system, which can minimize the eects of stress
(Almeida et al., 2020).
Likewise, the mixture of trinexapac-ethyl with fungicides
may reduce the plant height and impact wheat lodging
(Kleczewski & Whaley, 2018). There are no studies in the
literature indicating the eects of the growth regulators
application followed by glyphosate drift event in wheat.
We hypothesized that: (1) the injury caused by low doses
of glyphosate in wheat is lower in plants treated previously
with trinexapac-ethyl; (2) low doses of glyphosate that do not
show visual phytotoxicity increase yield of trinexapac-ethyl
treated wheat. Hence, this study aimed to assess the eects
of glyphosate drift after trinexapac-ethyl application on wheat
cultivars.
Material and methods
Two eld experiments were conducted in the winter seasons
of 2018 (Experiment I) and 2019 (Experiment II) in soil
classied as typical Dystrophic Red Oxisol with the following
physicochemical characteristics in the 0 cm to 20 cm layer:
56% clay, pH = 5,9; SMP (H
2
O) = 6,5; OM = 4,0%; P = 4,5
mg dm
-3
; K = 332,7 mg dm
-3
; Ca = 7,44 mg dm
-3
; Mg = 3,51
mg dm
-3
; CEC = 14,3 cmolc dm
-3
; SB = 82,4 cmolc dm
-3
; clay
= 56,1%. The monthly average temperature and rainfall data
observed during the experiments are shown in Figure 1.
May Jun Jul Ago Set Oct Nov
Mean Temperature (°C)
12
14
16
18
20
22
24
Rainfall (mm)
0
50
100
150
200
250
300
350
Temperature 2018
Temperature 2019
Rainfall 2018
Rainfall 2019
Figure 1. Mean temperature and rainfall data during
experiments in 2018 and 2019
The experimental design used was a randomized
complete block in a split plot factorial arrangement with four
replications. The main plots were composed of wheat cultivars
Cultivar TBIO Toruk (low height) and TBIO Sossego
(medium height) (Exp. I), and TBIO Audaz (low height) and
ORS Citrino (medium height) (Exp. II); Subplots comprised
trinexapac-ethyl (TE) growth regulator (0 and 125 g ai ha
-1
),
and glyphosate subdoses: 0; 3,6; 7,2; 18 and 36 g ae ha
-1
(Exp.
I), and 0; 9; 18; 36 and 72 g ae ha
-1
) were allocated in sub
subplot. The sub subplot size was 1,36 by 5 m.
The experiments were installed in succession with
Response of trinexapac-ethyl-treated wheat to glyphosate drift
2025. 18(1): 15-22 Ciencia y Tecnología. 17
soybean, carrying out weed control with glyphosate (1080
g ae ha
-1
) 27 days before sowing (DBS), followed by the
application of glufosinate (400 g ai ha
-1
) at planting date (Exp.
I), e glyphosate + metsulfuron-ethyl (1200 g ae ha
-1
+ 4,2 g ai
ha
-1
) being carried out later at 18 days before sowing (DBS),
followed by the application of paraquat (400 g ai ha
-1
) at 3
DBS (Exp. II). The wheat cultivars were sowed with a 0,17
m spacing between rows, establishing a nal population of
350 and 242 plants per square meter for (Exp. I) and (Exp. II)
respectively . The base fertilization was 35, 104, 52, 13 and 10
kg ha
-1
of N, P
2
O
5
, K
2
O, CaO and SO
4
, respectively, and the
nitrogen topdressing was carried out at the GS 14 and GS32
phenological stage according to the Zadoks scale with 32 and
45 kg Na ha
-1
in the form of urea, respectively. Pyroxsulam (18
g ai ha
-1
) was used for weed control in Exp. I, and clodinafop
(60 g ai ha
-1
+ 0,5% v/v mineral oil) following the metsulfuron
(3,2 g ai ha
-1
) in Exp. II. The herbicides applications were
performed in tillering stage of wheat (GS 14).
The treatments were applied sequentially, with a one-
hour interval between the application of trinexapac-ethyl and
glyphosate at the GS32 growth stage according to the Zadoks
scale (second node detectable and rst node perceptible).
All treatments were carried out with a backpack sprayer
pressurized with CO
2
and equipped with three 11002 fan spray
tips distanced 0,50 m apart, with an application volume of 150
L ha
-1
. In 2018, the applications were carried out at 8 am with
temperature of 23 and 17,9 °C, relative humidity of 61 and
76% and wind velocity of 1,1 and 0,9 m/s in 2018 and 2019,
respectively.
The variables assessed were crop injury at 28 days
after the application (DAA) using a scale of 0 to 100%,
where 0 represents no visible symptoms of treatments and
100% indicating plant death (SBCPD 1995). Plant height
was measured at 28 DAA and pre-harvest (112 days after
emergency) by taking ve random plants and measuring
the distance of the plant of the last leaf to the ground. The
wheat aboveground dry matter was determined at 28 DAA by
collecting plants within a 0,5 m section of two rows of each
subplot. Subsequently, the plants were bagged and dried at
60 ℃ for seven days.
The wheat parcels were harvested manually in ve rows
by three meters in length. After, the samples were threshed
and weighed to determine grain productivity, adjusted to 13%
moisture.
The normality of the data was veried using the Shapiro-
Wilk test and residue analysis. The analysis was performed
by year separately. The data were submitted to an analysis
of variance using F<0,05. The cultivar and regulator factors
were compared using Tukey’s test (p < 0,05), and, the eect
of glyphosate subdoses was tted by linear, four-parameter
Lorentzian, and three-parameter sigmoid regressions.
The statistical analysis and charts were carried out with
the assistance of the software RBio (Bhering, 2017) and
SigmaPlot version 10.0.
Results and discussion
The phytotoxicity caused by subdoses of glyphosate was less
than 10% for 36 g ae ha
-1
in exp. I (2018) (Supplementary
material). In the exp. II (2019), there was a cultivar by
trinexapac-ethyl by glyphosate subdoses interaction for
phytotoxicity, which increased linearly for both cultivars,
and the cultivar Citrino was slightly more tolerant to
glyphosate when compared to cultivar TBIO Audaz (Figure
2). Trinexapac-ethyl potentialize the phytotoxicity symptoms
of glyphosate for cultivar TBIO Audaz in 10% at 72 g ae
ha
-1
of glyphosate, and whereas cultivar ORS Citrino was
not inuenced by trinexapac-ethyl. One of the possible
explanations for the highest toxicity presented in the cultivar
TBIO Audaz cultivar comes from the cultivar owner itself,
which recommends avoiding pesticides mixtures because
this cultivar is more sensitive than others and may present
phytotoxicity symptoms (Biotrigo, 2023).
Glyphosate (g ae ha
-1
)
0 9 18 36 72
Phytotoxicity (%)
0
20
40
60
80
Audaz with TE y=-8,72+1,05x; R
2
=0,94
Audaz without TE y=-7,02+0,94x; R
2
=0,94
Citrino with TE y=-7,09+0,83x; R
2
=0,94
Citrino without TE y=-7,33+0,81x; R
2
=0,94
Figure 2. Phytotoxicity of wheat cultivar (TBIO Audaz
and ORS Citrino) in response to trinexapac-ethyl and
subdoses of glyphosate at 28 days after application in
winter season of 2019. Bars represent 95% condence
interval
Cultivar sensitivity may also be related to an increase
in glyphosate absorption and translocation in association
with trinexapac-ethyl. McCullough & Hart (2010) veried
greater absorption of bispiribac in Poa annua, Lolium perenne
and Agrostis stolonifera when trinexapac-ethyl was early
applied or in tank mixture with the herbicide. According to
the authors, the increase in herbicide absorption provided by
trinexapac-ethyl may be due to adjuvants in the formulation of
the growth regulator. Similarly, trinexapac-ethyl in a tank mix
with glyphosate increases the control of P. annua compared to
the glyphosate alone (Baldwin et al., 2015). Instead, Bearss
et al. (2021) reported that trinexapac-ethyl in tank mixture
Da Silva et al., 2025
2025. 18(1):15-22
Ciencia y Tecnología.18
with fenoxaprop, quinclorac or mesotrione had no benets or
antagonism in controlling Digitaria ischaemum.
Cultivar by trinexapac-ethyl interaction and glyphosate
subdoses eect were detected for plant height at 28 DAA and
pre-harvest in winter season 2018 (Exp. I) (Table 1 and Figure
3). The cultivar Sossego was higher than Cultivar TBIO Toruk
in treated or non-treated with trinexapac-ethyl at pre-harvest.
However, the percentage of reduction in Sossego treated
with trinexapac was twice as high compared than cultivar
TBIO Toruk in pre-harvest plant height. The plant height was
linearly reduced by glyphosate subdoses at 28 DAA and pre-
harvest in 2018, with the reduction being more signicant in
the 36 g ae ha
-1
, around 7,3 and 5,1% at 28 DAA and pre-
harvest, respectively (Figure 3A).
Table 1. Plant height (cm) in response to trinexapac-ethyl
and wheat cultivars at pre-harvest in winter season of
2018
Wheat cultivars
Trinexapac-ethyl
With Without
TBIO Sossego 69,5 Ba 77,8 Aa
TBIO Toruk 63,6 B b 67,3 A b
Plant height results were averaged over glyphosate subdoses
(0 to 36 g ae ha
-1
). Identical upper- and lower-case letters in
the row and column, respectively, do not dier by Tukey’s test
(p < 0,05). DAA= days after trinexapac-ethyl and glyphosate
subdose application.
In 2019, glyphosate subdoses eect was detected for plant
height at 28 DAA, and glyphosate at 72 g ae ha
-1
reduced
22% the wheat plant height in average over trinexapac-ethyl
and cultivars treatments (Figure 3B). Plant height at pre-
harvest was inuenced by cultivar by glyphosate subdoses
and trinexapac-ethyl by glyphosate subdoses interactions
(Figure 3C and 3D). The application of glyphosate at 72 g
ae ha
-1
reduced cultivar TBIO Audaz plant height in 24%,
while cultivar ORS Citrino plant height was reduced by 16%
at the highest tested subdose averaged over trinexapac-ethyl
treatments (Figure 3C). The trinexapac-ethyl associated with
glyphosate had impact on plant height reductions from 11,6%
to 15,2% from 9 to 72 g ae ha
-1
of glyphosate compared plants
treated with glyphosate alone (Figure 3D).
A
000
0000000000000 4444444444444444 7777777777777777 18181818181818181818181818181818 36363636363636363636363636363636
Plant height (cm)
45
50
55
60
65
70
75
80
28 DAA y=53,9 - 0,11*x; R
2
=0,92
Pre-harves t y=70,8 - 0,10*x; R
2
=0,92
B
0 9 18 36 72
Plant height (cm)
50
55
60
65
70
75
80
85
y=76,27/1+(x/131,11)
2,04
; R
2
=0,99
C
Glyphosate (g ae ha
-1
)
0 9 18 36 72
Plant height (cm)
50
60
70
80
90
100
Audaz y=78,50/1+x/154,60)
1,50
; R
2
=0,98
Citrino y=84,86/1+x/122,66)
3,08
; R
2
=0,97
D
Glyphosate (g ae ha
-1
)
0 9 18 36 72
Plant height (cm)
50
60
70
80
90
100
With TE y=78,8/1+(x/195,7)
1,5
; R
2
=0,97
Without TE y=88,5/1+(x/122,5)
2,47
; R
2
=0,98
Figure 3. Plant height in response to glyphosate subdoses at in winter season of 2018 (A), and at 28 DAA (B) in winter
season of 2019. Plant height at pre-harvest in response to glyphosate subdoses and wheat cultivars (C) and in response
to glyphosate subdoses and trinexapac-ethyl (D) in winter season of 2019
.
Bars represent 95% condence interval.
DAA= days after trinexapac-ethyl and glyphosate subdose application, DAE= days after emergence
Response of trinexapac-ethyl-treated wheat to glyphosate drift
2025. 18(1): 15-22 Ciencia y Tecnología. 19
According to Lassiter et al. (2007), among the visible
lesions caused by herbicides is the delay in plant development,
and the plant height reduction is directly related to the action
mechanism of glyphosate, which acts by inhibiting the
activity of EPSPs enzyme. As a result, the shikimate pathway
is interrupted and the synthesis of proteins in the apical
meristems, resulting in the interruption of development.
Associated with this is the eect of trinexapac-ethyl, which
acts in reducing the active gibberellic acid levels, by inhibits
the 3β-hydroxylase enzyme (Zagonel & Fernandes, 2007).
Hence, the decrease in the gibberellin levels in the plant
results in less signicant growth, given that it is responsible
for cell division and elongation (Taiz & Zeiger, 2013).
Symptoms and reduction in plant height from glyphosate
subdoses vary according to cultivars, growth stages and
environmental conditions. The results found in this study
are similar to those found by Roider et al. (2007), which
symptoms by glyphosate in wheat ranged from 49% to 70 g
ae ha
-1
and 80% to 84 g ae ha
-1
when applied in the jointing
growth stage, and reduction of up to 26% in plant height at
70 g ae ha
-1
. Nevertheless, symptoms caused by subdoses of
glyphosate up to 84 g ae ha
-1
are minimal when applied at the
panicle initiation growth stage (Davis et al., 2013).
Wheat aboveground dry weight response was inuenced
by cultivar by trinexapac-ethyl by glyphosate subdoses
interactions in 2019 (Figure 4B). Trinexapac-ethyl reduced
cultivar TBIO Audaz aboveground dry weight by about
22% in nontreated plants with subdoses of glyphosate;
however, trinexapac-ethyl did not alter Cultivar ORS Citrino
aboveground dry weight. According to Hawerroth et al.
(2015) trinexapac-ethyl can decrease vegetative growth,
consequently reducing the production of straw. Contrary,
isolated trinexapac-ehtyl does not interfere in the Cultivar
ORS Citrino aboveground dry weight , however trinexapac-
ethyl and glyphosate interaction were more harmful, and in the
absence of trinexapac-ethyl, an increase of 16% aboveground
dry weight was estimated at 20 g ae ha
-1
of glyphosate.
Changes in the carbon distribution shoots root ratio is a
response to the use of trinexapac-ethyl. Chavarria et al. (2015)
reported a change in carbon accumulation between shoot and
root, with an increase of up to 44% in plant root mass. The
increase in Cultivar ORS Citrino aboveground dry weight
under low doses of glyphosate may be described as a hormesis
eect. Similar results were observed by Silva et al. (2020) in
white oat, for which the authors veried an increase of up to
43% in dry matter at 14,9 g ae ha
-1
of glyphosate. Other studies
reported in the literature review by Belz and Duke (2014),
evinced increases in dry matter of crops such as soybean,
maize, barley, and eucalyptus with low doses varying from 10
g ae ha
-1
to 25 g ae ha
-1
of glyphosate.
Wheat yield was aected by cultivar by subdose of
glyphosate interaction, therefore, wheat yield was not aected
by the main eects of trinexapac-ethyl (Figure 4A and C).
In 2018, cultivar TBIO Toruk yield of nontreated plants
with glyphosate was 9% higher than Sossego. However, the
application of glyphosate at 36 g ae ha
-1
reduced cultivar TBIO
Toruk yield by 11%. The Sossego yield was increased by up to
30% by glyphosate subdoses ranging between 3,6 to 18 g ae
ha
-1
compared to untreated plants, and wheat yield from plants
treated with glyphosate applied at 36 g ae ha
-1
was similar to
the nontreated plants. Several studies have shown that low-
dose glyphosate exposure is not without eects on individual
species, but can lead to changes in plant growth, such as
hormesis (Brito et al., 2018).
B
Glyphosate (g ae ha
-1
)
0 9 18 36 72
Dry matter (kg ha
-1
)
2000
3000
4000
5000
6000
7000
Audaz com TE:y=5154/1+(x/82,8)
4,1
; R
2
=0,96
Audaz sem TE: y=6063/1+(x/153,15)
0,7
; R
2
=0,82
Citrino com TE: y=4243/1+(x/112,10)1,95; R
2
=0,95
Citrino sem TE: y=3462 + 1320/(1+(x-19,9)/19,7)
2
; R
2
=0,99
C
Glyphosate (g ae ha
-1
)
0 9 18 36 72
Yield (kg ha
-1
)
1000
2000
3000
4000
5000
6000
Audaz y=5126/1+(x/63,4)
2,77
; R
2
=0,99
Citrino y=4969/1+(x/77,53)
8,93
; R
2
=0,99
A
Glyphosate (g ae ha
-1
)
00000000 44444444 77777777 1818181818181818 3636363636363636
Yield(kg ha
-1
)
2000
2500
3000
3500
4000
Sossego y=2592/960/(1+(x-10,5)/7,2)
2
; R
2
=0,83
Toruk y=2607+445/(1+(x-4,4)/10,9)
2
; R
2
=0,98
Figure 4. Eect of glyphosate subdoses, trinexapac-ethyl (TE) and wheat cultivars interactions on wheat yield (A and
C) aboveground dry weight (B) in winter season in 2018 (A) and in 2019 (B e C). Bars represent 95% condence inter-
val
Da Silva et al., 2025
2025. 18(1):15-22
Ciencia y Tecnología.20
In 2019, subdoses of glyphosate from 9 to 18 g ae ha
-1
does
not aect on wheat yield of cultivar TBIO Audaz , but yield
was reduced 17 and 59%, respectively, when treated with 36
and 72 g ae ha
-1
of glyphosate (Figure 4C). The Cultivar ORS
Citrino yield remained unchanged up to the subdose of 36 g
ae ha
-1
of glyphosate, and with estimated yield loss of 34% at
72 g ae ha
-1
. Although Cultivar ORS Citrino plants showed
phytotoxicity symptoms of 22% in the subdose of 36 g ae ha
-1
,
this was not enough to reduce yield. There were no dierences
in yield between cultivars TBIO Audaz and ORS Citrino up
to 18 g ae ha
-1
of glyphosate; however, the dierences were
estimated at 884 and 1158 kg ae ha
-1
for the subdoses of 36 and
72 g ae ha
-1
, respectively. The ED50 parameter of the logistic
equations may also be used to describe this higher tolerance
of cultivar ORS Citrino than cultivar TBIO Audaz , given that
77,5 g ae ha
-1
of glyphosate is needed to reduce the yield by
50%, while this dose is 63,4 g ae ha
-1
for the cultivar TBIO
Audaz .
Literature reports indicate that wheat yield response
as a function of subdose of glyphosate is highly variable.
Generally, glyphosate drift can have greater impacts on wheat
yields when it occurs in the early growth stages (Davis et al.,
2013). Deeds et al. (2006) found a yield loss ranged from 0 to
80% when wheat were subjected to 25,5 g ae ha
-1
of glyphosate
at the jointing and owering growth stages. Results obtained
by Roider et al., (2007) indicate lower impacts of glyphosate
on wheat yield, with a 29% reduction in the 70 g ae ha
-1
.
The low herbicide doses in wheat seem response to others
factors including genetic, environmental (temperature, soil
fertility, precipitation), intraspecic competition, herbicide
deposition (Belz & Sinkkonen, 2019; Brito et al., 2018), since
plant response between the two years. The long-term repeated
glyphosate drift can evolve recurrent selection for herbicide in
crops or weeds. In crops, the eect of recurrent of low doses
herbicide is reported in barley, which generated progeny
fast growing plants and more tolerant to glyphosate (Belz &
Sinkkonen, 2021).
The wheat response to trinexapac-ethyl varies depending
on the environment, management and genetics, and tall
cultivars are more responsive to regulator growth. Similar
results were also observed by Miziniak and Matysiak (2016)
who veried the wheat response to trinexapac-ethyl dependent
on a series of conditions that imply in cultivar genetics,
season and growth regulator application rate, use of mixed
agrochemicals and environmental conditions.
Conclusion
The cultivar dierences play a signicant role in wheat
response to glyphosate drift after trinexapac-ethyl application.
Trinexapac-ethyl did not consistently reduce glyphosate injury.
Trinexapac-ethyl treatment reduced plant height, particularly
in cultivar TBIO Audaz and at higher glyphosate doses.
Cultivar ORS Citrino exhibited a higher overall tolerance to
glyphosate compared to cultivar TBIO Audaz, with minimal
yield reductions even at moderate glyphosate subdoses. Low
doses of glyphosate stimulus Sossego cultivar yield
References
Almeida, D.P., Ferreira, M.C., Decaro Jr, S.T., Yamauchi,
A.K., & Agostini. A.R. (2015). Droplets size categories
and application volumes in burndown of plant covers.
Revista Brasileira de Herbicidas, 14(1):73-82. https://
doi.org/10.7824/rbh.v14i1.280
Almeida Moreira, B. R., da Silva Viana, R., Monteiro
de Figueiredo, P. A., Manzani Lisboa, L. A., Tadao
Miasaki, C., Chagas Magahães, A., Bispo Ramos, S.,
de Almeida Viana, C. R., Dias Rezende Trindade, V., &
May, A. (2020). Glyphosate plus carboxylic compounds
boost activity of free radical-scavenging enzymes in
sugarcane. Agriculture, 10(4). https://doi.org/10.3390/
agriculture10040106
Baldwin, C.M., Brede, A.D., & Mayer, J.J. (2015).
Growth regulation and tank mixing associated with a
glyphosate-tolerant perennial ryegrass cultivar. Hort
Technology, 25(2), 214-220. https://doi.org/10.21273/
HORTTECH.25.2.214
Bearss, R.C., Patton, A.J., Brosnan, J.T., & Breeden, G.K.
(2021). Postemergence smooth crabgrass control is not
inuenced by herbicide combinations with trinexapac-
ethyl. Crop Forage & Turfgrass Management, 7(1):
e20082. https://doi.org/10.1002/cft2.20082
Belz, R.G., & Duke, S.O. (2014). Herbicide and plant
hormesis. Pest Management Science, 70(5), 698-707.
https://doi.org/10.1002/ps.3726
Belz, R.G., & Sinkkonen, A. (2021). Low glyphosate doses
change reproduction and produce tolerant ospring
in dense populations of Hordeum vulgare. Pest
Management Science, 77(10), 4770-4784. https://doi.
org/10.1002/ps.6522
Belz, R.G., & Sinkkonen, A. (2019). Low toxin doses change
plant size distribution in dense populations – glyphosate
exposed Hordeum vulgare as a greenhouse case study.
Environment International, 132, 105072. https://doi.
org/10.1016/j.envint.2019.105072
Biotrigo (2023). Biotrigo cultivares. https://biotrigo.com.br/
cultivares/portfolio/tbio_audaz/47.
Bhering, L.L. (2017). Rbio: A Tool For Biometric And
Statistical Analysis Using The R Platform. Crop
Breeding and Applied Biotechnology, 17(2), 187-190.
https://doi.org/10.1590/1984-70332017v17n2s29
Brito, I.P.F.S., Tropaldi, L., Carbonari, C.A., & Velini, E.D.
(2018). Hormetic eects of glyphosate on plants. Pest
Management Science, 74(5), 1064–1070. https://doi.
org/10.1002/ps.4523
Response of trinexapac-ethyl-treated wheat to glyphosate drift
2025. 18(1): 15-22 Ciencia y Tecnología. 21
Brown, L.R., Robinson, D.E., Young, B.G., Loux, M.M.,
Johnson, W.G., Nurse, R.E., Swanton C.J., & Sikkema,
P.H. (2009). Response of corn to simulated glyphosate
drift followed by in-crop herbicides. Weed Technology,
23(1), 11–16. https://doi.org/10.1614/WT-08-067.1
Chavarria, G., Rosa, W.P., Homann, L., & Durigon. M.R.
(2015). Regulador de crescimento em plantas de trigo:
reexos sobre o desenvolvimento vegetativo, rendimento
e qualidade de grãos. Revista Ceres, 62(6): 583-588.
https://doi.org/10.1590/0034-737X201562060011
Davis, B., Scott, R.C., Norsworthy, J.K., & Gbur. E.E. (2013).
Response of wheat (Triticum aestivum) to low rates of
glyphosate and glufosinate. Crop Protection, 54, 181-
184. https://doi.org/10.1016/j.cropro.2013.07.018
Deeds, Z., Al-Khatib, K., Peterson, D.E., & Stahlman, P.W.
(2006). Wheat response to simulated drift of glyphosate
and imazamox applied at two growth stages. Weed
Technology, 20(1): 23-31. https://doi.org/10.1614/WT-
04-273R.1
Duke, S.O. (2015) Perspectives on transgenic, herbicide-
resistant crops in the United States almost 20 years after
introduction. Pest Management Science, 71(5):652-657.
https://doi.org/10.1002/ps.3863
Gandolfo, M.A., Carvalho, F.K., Chechetto, R.G., Gandolfo,
U.D., & Moraes, E.D. (2014). Eect of working pressure
at dierent spray nozzles on drift quantication in wind
tunnel. Engenharia Agrícola, 34(1), 66-73. https://doi.
org/10.1590/S0100-69162014000100008
Hawerroth, M.C., Gonzalez da Silva, J.A.G., Souza, C.A.,
Oliveira, A.C., Luche, H.S., Zimmer, C.M., Hawerroth
F.J., & Schiavo, J. (2015). Redução do acamamento em
aveia branca com o uso de regulador de crescimento
ethyl- trinexapac. Pesquisa Agropecuária Brasileira,
50(2): 115-125. https://doi.org/10.1590/S0100-
204X2015000200003
Kelley, K. B., Wax, L.M., Hager, A.G., & Riechers, D.E.
(2005). Soybean response to plant growth regulator
herbicides is aected by other postemergence herbicides.
Weed Science, 53(1), 101–112. https://doi.org/10.1614/
WS-04-078R
Kleczewski, N.M., & Whaley, C. (2018). Assessing the utility
of the growth regulator trinexapac-ethyl and fungicides
in mid-Atlantic soft red winter wheat production systems.
Crop Protection, 104, 60-64. https://doi.org/10.1016/j.
cropro.2017.10.011
Lassiter, B. R., Burke, I., Thomas, W., Pline-Srnić, W. A.,
Jordan, D., Wilcut, J. W., & Wilkerson, G. (2007). Yield
and physiological response of peanut to glyphosate drift.
Weed technology: a journal of the Weed Science Society
of America, 21(4), 954–960. https://doi.org/10.1614/
WT-07-045.1
Mccoy, J., Golden, B., Bond, J., Dodds, D., Bararpour, T., &
Gore, J. (2021). Rice response to sublethal concentrations
of paraquat, glyphosate, saufenacil, and sodium chlorate
at multiple late-season application timings as inuenced
by exposure. Weed Technology, 35(6), 980-990. https://
doi.org/10.1017/wet.2021.61
Mccullough, P.E., & Hart, S.E. (2010). Trinexapac-ethyl
inuences bispyribac-sodium absorption and ecacy
for annual bluegrass (Poa annua) control in creeping
bentgrass (Agrostis stolonifera). Weed Technology,
24(3), 326–331. https://doi.org/10.1614/WT-08-015.1
Miziniak, W., & Matysiak, K. (2016). Two tank-mix adjuvants
eect on yield and quality attributes of wheat treated
with growth retardants. Ciência Rural, 46(9), 1559-
1565. https://doi.org/10.1590/0103-8478cr20150842
Pio de Oliveira, G.M.P., Gandolfo, M.A., Dalazen, G., Osipe,
J.B., Pio de Oliveira, S.M.P., & Silva, M.A.A. (2021).
Regression analysis to evaluate herbicide drift and injury
in Roundup Ready cotton in wind tunnel. Revista Ciência
Agronômica, 52(2), 1-8. https://doi.org/10.5935/1806-
6690.20210025
Perkins, D.B., Abi-Akar F., Goodwin, G., & Brain, R.A.
(2022) Characterization of eld-scale spray drift
deposition and non-target plant biological sensitivity: a
corn herbicide (mesotrione/s-metolochlor) case study.
Pest Management Science, 78(7), 3193-3206. https://doi.
org/10.1002/ps.6950.
Roider, C.A., Grin, J.L., Harrison, S.A., & Jones, C.A.
(2007). Wheat response to simulated glyphosate drift.
Weed Technology, 21(4), 1010-1015. https://doi.
org/10.1614/WT-07-073.1
SBCPD - Sociedade Brasileira da Ciência das Plantas
Daninhas. (1995). Procedimentos para instalação,
avaliação e análise de experimentos com herbicidas.
Sociedade Brasileira da Ciência de Plantas Daninhas.
Silva, D.R.O., Silva, A.A.A., Novello, B.D., Rieder, E.,
Aguiar, A.C.M., & Basso, C.J. (2020). Nitrogen
availability and glyphosate hormesis on white oat. Planta
Daninha, 38, e020230864. https://doi.org/10.1590/
S0100-83582020380100071
Shah, A.N., Tanveer, M., Rehman, A.U., Anjum, S.A., Iqbal,
J., & Ahmad, R. (2016) Lodging stress in cereal-eects
and management: an overview. Environmental Science
Pollution Research International, 24(6), 5222-5237.
https://doi.org/10.1007/s11356-016-8237-1.
Taiz, L., & Zeiger, E. (2004). Fisiologia Vegetal. Artmed.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4242361/
Wiersma, J.J., & Durgan, B.R. (2017). Spring wheat response
to simulated glyphosate drift. Crop, Forage & Turfgrass
Management, 3(1), 1-5. https://doi.org/10.2134/
cftm2017.09.0066
Da Silva et al., 2025
2025. 18(1):15-22
Ciencia y Tecnología.22
Zagonel, J., & Fernandes, E.C. (2007). Doses e épocas de
aplicação de redutor de crescimento afetando cultivares
de trigo em duas doses de nitrogênio. Planta Daninha,
25(2), 331-339. https://doi.org/10.1590/S0100-
83582007000200013
Copyright (2025) © Diecson Ruy Orsolin da Silva, Rodrigo Zeni y Claudir José Basso.
Este texto está protegido bajo una licencia internacional Creative Commons 4.0. Usted es libre para compartir, copiar y redistribuir el material
en cualquier medio o formato. También podrá adaptar: remezclar, transformar y construir sobre el material. Ver resumen de la licencia.
