Effect of naringenin and its derivatives on the probing behavior of myzus persicae (Sulz.)

Article abstract of DOI:10.3390/molecules25143185

Substances that alter insect behavior have attracted a lot of attention as potential crop protection agents. Naringenin (5,7,40-trihydroxyflavanone) is a naturally occurring bioactive flavanone. We evaluated the influence of naringenin on aphid activities during individual phases of probing and feeding and the effect of structural modifications of naringenin on its activity towards aphids. We monitored the probing behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae) using the Electrical Penetration Graph (EPG) technique. The chemical modifications were the substitution of hydrogen atoms with methyl, ethyl or pentyl groups and the replacement of the carbonyl group in naringenin and its derivatives with an oxime moiety. Depending on the substituents, the activity of naringenin-derived compounds varied in potency and mode of action. Naringenin was an attractant of moderate activity, which enhanced sap ingestion. The naringenin derivative with two methyl groups-7,40-di-O-methylnaringenin-was a deterrent, which hindered aphid probing in non-phloem tissues. Naringenin oxime derivatives with methyl substituents-7,40-di-O-methylnaringenin oxime, 7-O-methylnaringenin oxime, and 5,7,40-tri-O-methylnaringenin oxime-and the derivative with a pentyl substituent-7-O-pentylnaringenin oxime-were strong attractants which stimulated aphid probing in non-phloem tissues and the ingestion of phloem sap.

Full text of DOI:10.3390/molecules25143185

molecules
Article
Effect of Naringenin and Its Derivatives on the
Probing Behavior of Myzus persicae (Sulz.)
Katarzyna Stec 1, Joanna Kozłowska 2 , Anna Wróblewska-Kurdyk 1, Boz˙ena Kordan 3,
1,
Mirosław Anioł 2 and Beata Gabrys´
*
1
Department of Botany and Ecology, Institute of Biological Sciences, University of Zielona Góra, Szafrana 1,
65-516 Zielona Góra, Poland; katarzyna.rozycka1985@interia.pl (K.S.);
a.wroblewska-kurdyk@wnb.uz.zgora.pl (A.W.-K.)
2
Department of Chemistry, Faculty of Biotechnology and Food Science, Wrocław University of Environmental
and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; joannakozlowska3@gmail.com (J.K.);
miroslaw.aniol@upwr.edu.pl (M.A.)
Department of Entomology, Phytopathology and Molecular Diagnostics, University of Warmia and Mazury
in Olsztyn, Prawochen´skiego 17, 10-719 Olsztyn, Poland; bozena.kordan@uwm.edu.pl
Correspondence: b.gabrys@wnb.uz.zgora.pl
3
*
ꢀꢁꢂꢀꢃꢄꢅꢆꢇ
Academic Editors: George Grant and Angelo Canale
Received: 28 May 2020; Accepted: 8 July 2020; Published: 13 July 2020
ꢀꢁꢂꢃꢄꢅꢆ
Abstract: Substances that alter insect behavior have attracted a lot of attention as potential crop
protection agents. Naringenin (5,7,40-trihydroxyflavanone) is a naturally occurring bioactive flavanone.
We evaluated the influence of naringenin on aphid activities during individual phases of probing
and feeding and the effect of structural modifications of naringenin on its activity towards aphids.
We monitored the probing behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae) using the
Electrical Penetration Graph (EPG) technique. The chemical modifications were the substitution of
hydrogen atoms with methyl, ethyl or pentyl groups and the replacement of the carbonyl group in
naringenin and its derivatives with an oxime moiety. Depending on the substituents, the activity of
naringenin-derived compounds varied in potency and mode of action. Naringenin was an attractant
of moderate activity, which enhanced sap ingestion. The naringenin derivative with two methyl
groups—7,40-di-O-methylnaringenin—was a deterrent, which hindered aphid probing in non-phloem
tissues. Naringenin oxime derivatives with methyl substituents—7,40-di-O-methylnaringenin oxime,
7-O-methylnaringenin oxime, and 5,7,40-tri-O-methylnaringenin oxime—and the derivative with a
pentyl substituent—7-O-pentylnaringenin oxime—were strong attractants which stimulated aphid
probing in non-phloem tissues and the ingestion of phloem sap.
Keywords: electrical penetration graph; peach potato aphid; antifeedants; attractants; structure-
activity relationships
1. Introduction
Naringenin (5,7,40-trihydroxyflavanone) is a natural flavonoid, most common in Citrus
fruits, known to have bioactive effects on human health, such as antidiabetic, antidepressant,
immunomodulatory, antitumor, anti-inflammatory, DNA protective, and antioxidant effects [
Various effects of naringenin on insect development and behavior were also reported; naringenin
inhibited the feeding of adult Japanese beetles Popillia japonica (Newman) (Coleoptera: Scarabaeidae) [ ],
caused a reduction in larval growth and development in the common cutworm Spodoptera litura
(Fabricius) (Lepidoptera: Noctuidae) [ ], stimulated oviposition in the spotted pink ladybeetle
1,2].
3
4
Coleomegilla maculata De Geer (Coleoptera: Coccinellidae) [5], and impaired the learning abilities of the
honey bee Apis mellifera L. (Hymenoptera: Apidae) [6].
Molecules 2020, 25, 3185; doi:10.3390/molecules25143185
www.mdpi.com/journal/molecules

Molecules 2020, 25, 3185
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Aphids (Hemiptera: Aphididae) are responsible for at least 2% of losses caused by insect feeding
in the world’s crops [ ]. In addition to the removal of assimilates from plant phloem transporting
7
vessels, aphids transfer viral diseases from infected to healthy plants. The extremely polyphagous
peach potato aphid Myzus persicae (Sulz.) can transmit over 100 plant viruses among plants within
over 40 families [
8]. To our knowledge, there exists only one published study that reports the effect of
naringenin on aphids. Goławska et al. [
9
] showed that the addition of naringenin into a sucrose–agarose
diet caused an increase in the duration of the pre-reproductive period and mortality, as well as a
decrease in fecundity and the intrinsic rate of natural increase in the pea aphid Acyrthosiphon pisum
(Harris). In the same study, the authors demonstrated that high concentrations of naringenin inhibited
the passive ingestion (analogous to passive ingestion of phloem sap on plants and represented by
EPG waveform g-E2) of the naringenin-supplemented sucrose–agarose diet, but stimulated the active
ingestion (analogous to active ingestion of xylem sap on plants and represented by EPG waveform
g-G) of the diet [9].
Nowadays, aphid control relies mainly on neurotoxic insecticides. However, several aphid species,
especially M. persicae, evolved diverse mechanisms of resistance to various insecticides [10,11]. At the
same time, a global trend for the reduction in insecticide use is observed in response to environmental
issues. In recent years, serious restrictions in neonicotinoid use have been established in the European
Union [12]. Therefore, there is a growing demand for the replacement of traditional insecticides, at least
in part, by natural product-based insect control agents. Specifically, behavior modifying substances
(repellents, antifeedants, attractants, etc.), which may cause the withdrawal of the herbivore from
the plant or other substrates, are searched for [13–15]. The exogenous application of xenobiotics
may alter aphid response to otherwise acceptable host plants, which has been shown in studies on
aphid antifeedants involving different chemical groups, including terpenoids, quassinoids, flavonoids,
and cyanogenic glycosides [
trap crops or barrier crops, in ‘push–pull’ strategies [21
9
,
16
–
20]. At the same time, aphids may be attracted to other areas, such as
23]. Unfortunately, the application of natural
–
compounds for the protection of plants is limited. The main constraints are the low content in natural
sources and usually complicated structures, which make their synthesis complex and expensive.
Therefore, the synthesis of natural compound analogues is one of the most promising ways leading
to their practical use in insect pest population control [24]. Structural transformations of the natural
molecule usually change the mode of action and potency of its activity [25,26]. The possibility of
reducing aphid infestation of crop plants by naringenin and its analogues application has never
been explored.
The aim of the present study was to assess the influence of naringenin on aphid activities
during individual phases of probing and feeding and evaluate the effect of structural modifications
of naringenin on its activity towards aphids. The chemical modifications were the substitution of
hydrogen atoms with methyl, ethyl or pentyl groups and the replacement of the carbonyl group in
naringenin and its derivatives with an oxime moiety. We monitored aphid probing with the Electrical
Penetration Graph (EPG) technique, which visualizes the movements of aphid mouthparts within
individual plant tissues. The values of parameters derived from EPG recordings are reliable and
accurate indicators of aphid behavioral responses to alteration in plant suitability due to exogenous
application of xenobiotics [19–24].
2. Results
The typical behavior of M. persicae on control untreated plants consisted of non-probing (11%
time of the 8 h experiment), probing in non-phloem tissues (34%), and probing in phloem tissues
(55%). Sap ingestion occupied 95% of the phloem phase. Aphid probing activities were divided into
19.8 (
of these probes contained a phloem phase (Table 1). M. persicae needed approximately 2.0 (
to reach phloem vessels and commence sap ingestion. In that time, 25% were non-probing activities.
Probing activities in non-phloem tissues before the first phloem phase were divided into 12.7 ( 8.8)
±
10.0) probes on average, and these probes were approximately 0.6 (
±
0.6) hours long. Nearly 10%
±
1.3) hours
±

Molecules 2020, 25, 3185
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events (probes) (Table 2). The phloem phase in M. persicae consisted of 4.4 (
±
2.8) separate periods and
almost all of these phloem phases included sap ingestion. Of these sap ingestion periods, 60% were
longer than 10 min and were 2.1 ( 2.2) hours long on average. The first contact with sieve elements
±
(the first phloem phase) was 1.7 (±2.4) hours long (Table 3).
M. persicae probing behavior on plants treated with naringenin and its derivatives (2–17)
(Figures 1 and 2) was significantly different from the aphid behavior on the control plants. Non-probing
activities were significantly reduced on plants treated with ( ) and (17). The total duration of the
non-phloem phase was significantly longer on ( )- and (12)-treated plants, and the phloem phase
was significantly shorter on ( )-treated plants than on the control plants. The total duration of sap
ingestion was longer on (13)-treated plants than on the control. The number of probes was lower,
and the probes were longer on ( )-, ( )-, ( )-, (13)-, (15)-, and (16)-treated plants (Table 1). During
the pre-phloem phase, i.e., the period before the first phloem phase occurred, the total duration of
non-probing was longer on ( )-treated plants but shorter on ( )-, ( )-, and (13)-treated plants than on
8
2
2
3
4
8
7
3
8
the control. The duration of probing in non-phloem tissues, the total time to the first phloem phase
and the first phloem sap ingestion phase from the onset of probing were shorter on (13)-treated plants
than on the control. The total number of probes and the number of short probes before the first phloem
phase were lower on (
3
)-, (4)-, (8)-, (13)-, (15)-, and (16)-treated plants (Table 2). The number of phloem
phases and the number of sap ingestion phases were lower on naringenin, (
3
)-, ( )-, ( )-, (10)-, (15)-,
7
8
and (17)-treated plants than on the control. On these plants, the first phloem phases were significantly
longer than on the control plants. The mean duration of phloem sap ingestion phase was longer on
naringenin-, (8)-, and (17)-treated plants than on the control (Table 3).
The comparison within the group of aphids on treated plants showed that the highest number of
probes occurred in aphids on (
16)-treated plants (4.4 4.2 and 5.2
phloem phase and phloem sap ingestion phase were longest in aphids on (
in contrast to aphids on (13)-treated plants (1.0 0.8 h) (Tables 1 and 2). The mean duration of the
7
)-treated plants (16.7
7.3 probes, respectively), the durations of periods before the first
)-treated plants (2.8 1.4 h)
±
9.7 probes) in contrast to aphids on (3)- and
(
±
±
7
±
±
phloem phase was the shortest in aphids on (
(15)-treated plants (5.0 ± 2.7 h) (Table 3).
2
)-treated plants (1.1
±
2.0 h) in contrast to aphids on
R2
O
O
O
O
R3
O
R1
Figure 1. Naringeninanditsderivatives. Naringenin: R1=H, R2=H, R3=H(1); 5,7,40-tri-O-methylnaringenin:
R1=CH3, R2=CH3, R3=CH3 (2); 5,7,40-tri-O-ethylnaringenin: R1=CH3CH2, R2=CH3CH2, R3=CH3CH2
(3); 7-O-ethylnaringenin: R1=CH3CH2, R2=H, R3=H (4); 7-O-pentylnaringenin: R1=CH3(CH2)4,
R2=H, R3=H (5); 7,40-di-O-ethylnaringenin: R1=CH3CH2, R2=H, R3=CH3CH2 (6); 7,40-di-O-
methylnaringenin: R1=CH3, R2=H, R3=CH3 (7); 7-O-methylnaringenin: R1=CH3, R2=H, R3=H (8).

Molecules 2020, 25, 3185
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Table 1. General aspects of Myzus persicae probing behavior on naringenin and naringenin derivatives (
1
–
17, Figures 1 and 2)-treated plants (means
±
SD). The
mean and SD values given are a representation of non-Gaussian data, but the statistical analysis was done by non-parametric tests, in which all individual data
were included; n—number of replications; C—pathway; E1—phloem salivation; E2—phloem sap ingestion; F—derailed stylet movements; G—xylem sap ingestion.
Different small letters in columns show significant differences in the values of specific parameters among aphids on plants treated with individual naringenin
derivatives (Kruskal–Wallis test, p < 0.05); different capital letters show significant differences in the values of specific parameters between aphids on plants treated
with individual compounds and control (Mann–Whitney U-test, p < 0.05).
Compound/EPG
Total Duration of
Non-Probing (h)
Total Duration of Probing in
Non-Phloem Tissues C + F + G (h)
Total Duration of
Phloem Phase E1 + E2 (h)
Total Duration of Sap
Ingestion Phase E2 (h)
Number of
Probes (#)
Mean Duration
of a Probe (h)
Sample Size
Parameter
Control
n = 16
n = 14
n = 13
n = 13
n = 13
n = 14
n = 14
n = 16
n = 13
n = 16
n = 14
n = 13
n = 14
n = 14
n = 14
n = 14
n = 12
n = 13
0.9 ± 1.2 A
0.8 ± 0.5 aA
1.3 ± 1.1 aA
0.9 ± 1.6 aA
0.5 ± 0.5 aA
0.8 ± 0.8 aA
0.6 ± 0.7 aA
1.2 ± 1.2 aA
0.3 ± 0.2 aB
0.8 ± 0.6 aA
0.6 ± 0.6 a A
0.7 ± 0.6 aA
0.7 ± 0.4 aA
0.3 ± 0.3 a B
1.0 ± 0.7 aA
0.6 ± 0.8 aA
0.7 ± 0.9 aA
0.8 ± 0.7 aA
2.7 ± 1.3 A
2.7 ± 1.8 aA
4.0 ± 1.7 aB
3.2 ± 1.4 aA
3.5 ± 1.8 aA
3.3 ± 2.3 aA
2.3 ± 1.8 aA
3.5 ± 1.9 aA
2.9 ± 2.1 aA
2.8 ± 1.6 aA
3.7 ± 2.3 aA
3.7 ± 2.0 aA
4.3 ± 2.0 aB
2.1 ± 1.5 aA
2.9 ± 1.6 aA
2.0 ± 1.8 aA
2.3 ± 1.8 aA
2.8 ± 1.9 aA
4.4 ± 1.7 A
4.5 ± 2.1 aA
2.7 ± 2.4 aB
4.0 ± 1.8 aA
3.9 ± 2.1 aA
3.9 ± 2.8 aA
5.1 ± 2.3 aA
3.3 ± 2.1 aA
4.8 ± 2.2 aA
4.4 ± 1.9 aA
3.7 ± 2.7 aA
3.6 ± 2.2 aA
3.0 ± 2.2 aA
5.6 ± 1.7 aA
4.1 ± 2.1 aA
5.5 ± 2.4 aA
4.9 ± 2.2 aA
4.4 ± 2.5 aA
4.2 ± 1.8 A
4.5 ± 2.1 aA
2.6 ± 2.4 aA
3.9 ± 1.8 aA
3.9 ± 2.1 a A
3.9 ± 2.8 aA
5.1 ± 2.3 aA
3.3 ± 2.2 aA
4.7 ± 2.2 aA
4.4 ± 1.9 aA
3.7 ± 2.7 aA
3.5 ± 2.2 aA
3.0 ± 2.2 aA
5.6 ± 1.7 aB
4.1 ± 2.1 aA
5.5 ± 2.4 aA
4.9 ± 2.2 aA
4.4 ± 2.5 aA
19.8 ± 10.0 A
19.1 ± 13.7 aA
24.2 ± 16.3 aA
10.8 ± 8.4 aB
12.9 ± 6.9 aB
20.3 ± 15.1 aA
13.1 ± 10.3 aA
22.3 ± 12.3 aA
11.5 ± 7.8 aB
17.3 ± 12.3 aA
14.9 ± 11.7 aA
15.8 ± 7.0 aA
15.5 ± 10.5 aA
11.1 ± 8.8 a B
19.7 ± 9.4 aA
11.9 ± 12.1 aB
9.8 ± 7.8 aB
0.6 ± 0.6 A
0.8 ± 1.0 aA
1.2 ± 2.2 aA
1.5 ± 2.0 aB
0.8 ± 0.5 aB
0.8 ± 0.8 aA
1.5 ± 1.9 aA
0.6 ± 0.6 aA
1.3 ± 1.2 aB
0.8 ± 0.7 aA
1.4 ± 2.0 aA
0.8 ± 1.0 aA
0.7 ± 0.4 aA
1.1 ± 0.7 aB
0.5 ± 0.3 aA
2.0 ± 2.5 aB
2.2 ± 2.7 aB
0.7 ± 0.6 aA
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
20.01 ± 4.2 aA

Molecules 2020, 25, 3185
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Table 2. Myzus persicae behavior in non-phloem tissues prior to the first phloem phase during probing on naringenin and naringenin derivatives (
1–17, Figures 1 and 2)-
treated plants (means SD); the mean and SD values given are a representation of non-Gaussian data, but the statistical analysis was done by non-parametric tests,
±
in which all individual data were included; n—number of replications; only replications where phloem phase occurred were included; C—pathway; E1—phloem
salivation; F—derailed stylet movements; G—xylem sap ingestion. Different small letters in columns show significant differences in the values of specific parameters
among aphids on plants treated with individual naringenin derivatives (Kruskal–Wallis test, p < 0.05); different capital letters show significant differences in the values
of specific parameters between aphids on plants treated with individual compounds and control (Mann–Whitney U-test, p < 0.05).
Total Duration of
Probing in Non-Phloem
Tissues C + F + G (h)
Compound/EPG
Total Duration of
Non-Probing (h)
Time from 1st Probe to
1st Phloem Phase E1 (h)
Sample Size
Number of Probes
Parameter
Control
n = 16
n = 13
n = 13
n = 12
n = 13
n = 13
n = 14
n = 15
n = 13
n = 16
n = 13
n = 12
n = 14
n = 14
n = 12
n = 14
n = 12
n = 11
0.4 ± 0.2 A
0.7 ± 0.5 aA
0.7 ± 0.7 aA
0.2 ± 0.2 aB
0.2 ± 0.2 aA
0.3 ± 0.4 aA
0.4 ± 0.3 aA
0.7 ± 0.4 aB
0.2 ± 0.2 aB
0.4 ± 0.3 aA
0.2 ± 0.2 aA
0.4 ± 0.6 aA
0.4 ± 0.3 aA
0.2 ± 0.1 aB
0.5 ± 0.4 aA
0.2 ± 0.2 aA
0.5 ± 0.8 aA
0.4 ± 0.3 aA
1.6 ± 1.2 A
1.8 ± 1.4 aA
1.8 ± 1.1 aA
2.0 ± 1.2 aA
1.4 ± 1.2 aA
1.0 ± 0.7 aA
1.7 ± 1.5 aA
2.2 ± 1.2 aA
2.0 ± 1.6 aA
1.5 ± 0.8 aA
1.9 ± 1.7 aA
2.3 ± 2.4 aA
1.8 ± 1.6 aA
0.9 ± 0.6 aB
1.2 ± 0.8 aA
1.0 ± 0.8 aA
1.5 ± 1.5 aA
1.5 ± 0.7 aA
12.7 ± 8.8 A
15.8 ± 13.6 abA
10.5 ± 8.7 abA
4.4 ± 4.2 aB
2.0 ± 1.3 A
2.4 ± 1.8 abA
2.5 ± 1.5 abA
2.1 ± 1.2 abA
1.5 ± 1.3 abA
1.3 ± 1.0 abA
2.1 ± 1.8 abA
2.8 ± 1.4 bA
2.1 ± 1.7 abA
1.8 ± 0.9 abA
2.1 ± 1.8 abA
2.7 ± 2.6 abA
2.1 ± 1.9 abA
1.0 ± 0.8 aB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
4.9 ± 4.0 abB
8.6 ± 7.9 abA
8.7 ± 7.6 abA
16.7 ± 9.7 bA
6.8 ± 7.3 abB
8.4 ± 6.4 abA
6.2 ± 4.1 abA
8.3 ± 7.0 abA
9.2 ± 8.1 abA
5.4 ± 5.0 abB
11.2 ± 7.4 abA
5.2 ± 3.5 abB
5.2 ± 7.3 aB
1.7 ± 1.1 abA
1.2 ± 0.9 abA
2.0 ± 2.0 abA
1.8 ± 1.0 abA
10.9 ± 7.8 abA

Molecules 2020, 25, 3185
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Table 3. Myzus persicae behavior associated with probing in sieve elements on naringenin and naringenin derivatives (
1
–
17, Figures 1 and 2)-treated plants (means
±
SD);
the mean and SD values given are a representation of non-Gaussian data, but the statistical analysis was done by non-parametric tests, in which all individual data
were included; n—replication number; * all replications were included in analysis (the missing phloem phase was quantified as 0.0); ** aphids that did not reach
phloem elements during 8 h experiment were excluded from this analysis; E1—phloem salivation; E2—phloem sap ingestion. Different small letters in columns show
significant differences in the values of specific parameters among aphids on plants treated with individual naringenin derivatives (Kruskal–Wallis test, p < 0.05);
different capital letters show significant differences in the values of specific parameters between aphids on plants treated with individual compounds and control
(Mann–Whitney U-test, p < 0.05).
Compound/EPG
Parameter
Number of Phloem
Phases E1 and E1 + E (#)
Number of Phloem Sap
Ingestion Phases (#)
Number of Sustained Sap
Ingestion Phases E2 > 10 min (#)
Mean Duration of 1st
Phloem Phase E1 + E2 (h)
Mean Duration of Phloem
Sap Ingestion Phase E2 (h)
Sample Size *
Sample Size **
Control
n = 16
n = 14
n = 13
n = 13
n = 13
n = 14
n = 14
n = 16
n = 13
n = 16
n = 14
n = 13
n = 14
n = 14
n = 14
n = 14
n = 12
n = 13
4.4 ± 2.8 A
1.9 ± 1.6 aB
3.1 ± 1.7 aA
2.4 ± 2.6 aB
2.6 ± 1.3 aA
3.1 ± 2.2 aA
2.8 ± 1.8 aA
1.9 ± 1.2 aB
2.2 ± 1.6 aB
2.9 ± 2.3 aA
2.1 ± 1.6 aB
2.9 ± 2.7 aA
3.1 ± 1.8 aA
3.1 ± 1.9 aA
2.9 ± 2.2 aA
1.8 ± 1.4 aB
2.6 ± 1.8 aA
1.7 ± 1.6 aB
4.4 ± 2.7 A
1.7 ± 1.2 aB
3.1 ± 1.7 aA
2.3 ± 2.3 aB
2.6 ± 1.3 aA
2.9 ± 2.1 aA
2.7 ± 1.7 aA
1.9 ± 1.2 aB
2.2 ± 1.6 aB
3.0 ± 2.4 aA
2.1 ± 1.6 aB
2.9 ± 2.7 aA
2.8 ± 1.7 aA
3.1 ± 1.9 aA
2.8 ± 2.2 aA
1.8 ± 1.4 aB
2.5 ± 1.8 aA
1.7 ± 1.6 aB
2.6 ± 1.5 A
1.4 ± 0.9 aA
1.6 ± 1.1 aA
1.5 ± 0.8 aA
1.5 ± 1.2 aA
1.8 ± 1.1 aA
1.8 ± 1.3 aA
1.6 ± 0.9 aA
1.6 ± 0.8 aA
1.6 ± 0.9 aA
1.6 ± 1.2 aA
2.0 ± 1.8 aA
1.6 ± 0.8 aA
2.0 ± 1.2 aA
2.1 ± 1.5 aA
1.4 ± 0.7 aB
1.9 ± 1.7 aA
1.5 ± 1.3 aA
n = 16
n = 13
n = 13
n = 12
n = 13
n = 13
n = 14
n = 15
n = 13
n = 16
n = 13
n = 12
n = 14
n = 14
n = 12
n = 14
n = 12
n = 11
1.7 ± 2.4 A
3.0 ± 2.3 abB
1.1 ± 2.0 aA
3.0 ± 2.4 abA
1.9 ± 2.3 abA
2.6 ± 3.1 abA
2.7 ± 3.0 abA
2.3 ± 2.2 abA
3.7 ± 2.5 abB
2.9 ± 2.5 abA
3.4 ± 2.8 abB
1.6 ± 2.2 abA
2.7 ± 2.2 abA
3.0 ± 3.1 abA
2.0 ± 2.3 abA
5.0 ± 2.7 bB
2.1 ± 2.2 A
3.4 ± 2.0 aB
1.5 ± 2.0 aA
3.2 ± 2.1 aA
2.3 ± 2.0 aA
2.8 ± 3.0 aA
2.8 ± 2.7 aA
2.5 ± 2.2 aA
3.6 ± 2.4 aA
3.0 ± 2.5 aA
3.2 ± 2.8 aA
2.1 ± 2.0 aA
2.8 ± 2.2 aA
3.3 ± 2.8 aA
2.4 ± 2.0 aA
4.7 ± 3.0 aB
3.4 ± 2.9 aA
4.0 ± 2.5 aB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
3.6 ± 2.9 abB
3.8 ± 2.7 abB

Molecules 2020, 25, 3185
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OH
R2
N
O
O
O
R3
R1
O
Figure 2. Naringenin oxime and its derivatives. Naringenin oxime: R1=H, R2=H, R3=H (9)
;
5,7,40-tri-O-methylnaringenin oxime: R1=CH3, R2=CH3, R3=CH3 (10); 5,7,40-tri-O-ethylnaringenin
oxime: R1=CH3CH2, R2=CH3CH2, R3=CH3CH2 (11); 7-O-ethylnaringenin oxime: R1=CH3CH2, R2=H,
R3=H (12); 7-O-pentylnaringenin oxime: R1=CH3(CH2)4, R2=H, R3=H (13); 7,40-di-O-ethylnaringenin
oxime: R1=CH3CH2, R2=H, R3=CH3CH2 (14); 7,40-di-O-methylnaringenin oxime: R1=CH3, R2=H,
R3=CH3 (15); 7-O-methylnaringenin oxime: R1=CH3, R2=H, R3=H (16); 7,40-di-O-pentylnaringenin
oxime: R1=CH3(CH2)4, R2=H, R3=CH3(CH2)4 (17).
3. Discussion
The pre-phloem and phloem phases of aphid probing in plant tissues are two crucial steps in the
chemosensory-based host plant selection and host plant acceptance processes. Allelochemicals are the
main cues used by aphids for host plant selection during either the pathway or phloem phase [16].
The long duration of probing time in non-phloem tissues as compared to total penetration time,
the relatively long time to the 1st phloem phase within a probe, and a failure in finding sieve elements
may be interpreted as pre-ingestive effects of antifeedants that restrain aphid probing at the level of
non-phloem tissues [27]. In contrast, the reduction in the number of probes and the elongation of
these probes indicates the attractant character of chemical factors. The long total and mean durations
of phloem sap ingestion may point to the ingestive mode of feeding stimulatory activity [28,29].
The interpretation of aphid behavior in response to the chemical properties of plant tissues is based
on studies on plant resistance mechanisms. Aphids feeding on susceptible plant genotypes have a
significantly greater duration of sieve element phase than when feeding on resistant genotypes and the
time taken to reach the first sieve element phase in resistant genotypes is significantly greater than in
susceptible genotypes [30–33].
Based on the comparison of the EPG-monitored M. persicae behavior on naringenin and naringenin
derivatives-treated plants to control and the overall trends for each compound, it is possible to group
the studied compounds according to their potential to modify aphid probing activities: (i) strong
attractants (8), (13), (15), and (16), which stimulated aphid activities in the non-phloem as well as
in the phloem tissues. In comparison to control untreated plants, on treated plants, aphids rarely
withdraw stylets from plant tissues (8, 13, 15, 16) and the non-probing time was significantly reduced
(
8, 13), which caused a significant reduction in time to reach phloem vessels from the onset of
probing (13), the individual phloem sap ingestion periods were long and rarely interrupted ( 15 16),
and the total duration of sap ingestion was longer (13); (ii) moderate attractants naringenin, ( ), (10),
and (17)—naringenin, (10), and (17) had no effect on aphid behavior during the pre-phloem phase
but encouraged sap ingestion, and ( ) caused a slight reduction in the number of phloem phases as
well as the number of probes and a decrease in the duration of non-probing before the phloem phase;
(iii) weak attractant ( ) caused a slight reduction in the number and a slight increase in the duration of
probes; (iv) weak deterrent ( ) caused aphid restlessness by hindering pre-phloem pathway activities,
which was manifested in the frequent withdrawals of stylets from plant tissues, an increased time of
8
,
,
3
3
4
7

Molecules 2020, 25, 3185
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non-probing, and, in consequence, a delay in reaching phloem vessels; (v) inactive compounds (2), (5),
(6), (
9), (11), (12), (14). In comparison to control, aphid behavior was not altered on plants treated with
these compounds.
The biological activity of a given compound is species-specific and depends on its structural
characteristics. Variations, such as incorporation of functional groups, epoxidation, or lactonization,
can produce radical changes in activity [29]. In our previous studies, we determined that chemical
modifications of naturally occurring terpenoids, e.g., incorporation of functional groups, epoxidation or
lactonization, evoked significant changes in their activity profiles. We have established that the potency
and persistence of behavioral effects on aphid probing of piperitone-,
isoxanthohumol-, and cis-jasmone-derived compounds depended on their substituents. Certain
modifications caused shifts from attractant to deterrent properties, or vice versa [24 26 29]. In the
present study, we also revealed specific structure–activity relationships. Naringenin appeared to be
an attractant of moderate activity. Three ethyl groups incorporated at positions 5,7, and 4’ in ( ) did
not significantly alter the naringenin activity. The compound with one methyl group in the position
7 ( ) was a weak attractant. However, the compound with two methyl groups in the positions 7
and 4’ ( ) was a weak deterrent. The incorporation of three methyl groups at positions 5,7, and 4’
), two ethyl groups at positions 7, and 4’ ( ), or one pentyl group at position 7 ( ) caused a loss
of naringenin activity towards M. persicae. Naringenin oxime ( ) was inactive towards M. persicae.
β-damascone-, xanthohumol-,
–
,
3
4
7
(2
6
5
9
However, the substitution of hydrogen atoms with methyl, ethyl or pentyl groups, in addition to oxime
moiety, caused a significant rise in the activity of some of the derived compounds. All naringenin
oxime (9) derivatives with methyl substituents at positions 7 (15), 7 and 4’ (16), and 5,7,4’ (10) and the
derivative with a pentyl substituent at position 7 (13) appeared strong attractants. Pentyl groups at
positions 7 and 4’ made the compound (17) a weak attractant. The ethyl group substituents did not
improve the activity of naringenin oxime (9); all derivatives with one (12), two (14), or three (11) ethyl
substituents remained inactive towards M. persicae.
The results of the experiments in the present work illustrate two major aspects of the biological
activity of naringenin and its derivatives that depend on their substituents: (1) the variation in the
potency of the behavioral effect and (2) a switch from attractant to deterrent properties. In summary,
the most effective transformations of the naringenin molecule were the substitutions of hydrogen
atom(s) in hydroxyl group(s) with methyl or pentyl group(s) in combination with the replacement
of the carbonyl group with an oxime moiety. The behavioral effects of these transformations were
manifested mainly in the stimulation of probing in non-phloem tissues as well as the ingestion of
phloem sap.
The results of the present study could be applied towards modifying aphid attraction or
deterrence to plants in the field using genetic modification or topical application of naringenin
or naringenin-derived analogues [1,34]. This is especially important in the context of virus
transmission. Aphids may acquire and inoculate viruses during various stages of plant penetration
with sucking–piercing mouthparts. During brief intracellular probes in the epidermis and parenchyma
(mesophyll in leaves) that precede feeding in phloem vessels, aphids may transmit nonpersistent
and semi-persistent viruses. When aphid stylets reach sieve elements, persistent viruses may be
transmitted [35–38]. It is crucial then, to deter aphid probing or at least prevent feeding, to protect plants
from pathogen infection and limit the virus spread within the field crops. Besides the direct negative
effect on aphid feeding, a deterrent that impedes activities during pre-phloem and phloem stylet
penetration should also prevent the transmission of non-persistent and persistent viruses, respectively.
Considering the activities of naringenin and its derivatives revealed here, the strong attractants (
8), (10),
(13), (15), and (16) have the highest potential for practical applications in ‘push–pull’ strategies. As the
probing and feeding stimulants, they can be applied topically to any species of barrier plant to pull
M. persicae out of the protected crop. By making barrier plants more attractive to aphids, virus spread
within the crop may be reduced [22]. In addition, the weak deterrent (
7) that makes aphids restless can
be applied on the crop plant to push M. persicae out of the crop plant stand.

Molecules 2020, 25, 3185
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4. Materials and Methods
4.1. Naringenin and Naringenin Derivatives
Naringenin (5,7,40-trihydroxyflavanone) was purchased from SIGMA (W530098). The naringenin
derivatives (2–17) were prepared as described previously by Kozłowska et al. [39]. Briefly, mono-
and di-O-alkyl compounds (4–8) were obtained by stirring anhydrous potassium carbonate and
significant excess of appropriate alkyl iodide in the solution of naringenin in anhydrous acetone at
room temperature for 24–96 h. After solvent evaporation and washing with a saturated brine,
the products were extracted with diethyl ether, dried, concentrated and separated by column
chromatography. Tri-O-alkyl derivatives of naringenin (2, 3) were obtained similarly to the method
mentioned above, but dimethylformamide was used instead of acetone; after stirring for 7–24 h at
room temperature, the reaction mixtures were neutralized with 1 M HCl and extracted with methylene
chloride. The reaction yields were in the range of 20–72%.
Syntheses of oximes (
9
–
17) were performed by stirring the O-alkyl derivatives of naringenin
(1.0 eq.) (
2–8), hydroxylamine hydrochloride (1.5 eq.), and anhydrous sodium acetate (1.5 eq.) in
anhydrous ethanol at 40–50 ◦C. The reaction mixtures were poured into ice water. The precipitated
crystals were collected, dried in a vacuum, and purified by column chromatography. The reaction
yields were in the range of 81–99%.
The purity of obtained compounds was monitored using thin layer chromatography, high-
performance liquid chromatography and proton nuclear magnetic resonance.
4.2. Aphid and Plant Cultures
Laboratory culture of the peach potato aphid Myzus persicae (Sulz.), kept as a multiclonal
colony (i.e., deriving from different parthenogenetically reproducing females), was maintained on
Brassica rapa L. ssp. pekinensis L. in the laboratory at 21 ◦C, 65% r.h., and L16:8D photoperiod. M. persicae
had originally been collected in the greenhouse and kept on B. rapa ssp. pekinensis in the laboratory
since 2000. The plants for the EPG experiments were B. rapa ssp. pekinensis and were grown under
similar laboratory conditions as aphid cultures, at 21 ◦C, 65% r.h., and L16:8D photoperiod. Plants were
grown in plastic pots (0.33 L) filled with fine garden soil commonly used for greenhouse experiments.
Plants were watered regularly, and no additional nutrients were supplied.
4.3. Preparation and Application of Compounds
To mimic the natural environment under laboratory conditions, naringenin and its analogues
were offered to aphids by application through their host plants. Preparation and application of the
compounds followed the procedure described by Polonsky et al. [40], later modified by Gabrys´ et al. [26].
Briefly, each compound was dissolved in 70% ethanol to obtain a 0.1% solution [40]. All compounds
were applied on the adaxial and abaxial leaf surfaces by immersing one leaf of the experimental plant
in the ethanolic solution of a given compound for 30 s. Leaves of similar size of the control plants were
immersed in 70% ethanol that was used as a solvent for the studied compounds. There was no effect of
ethanol application on aphid probing behavior and plant condition [41]. Treated and control leaves
were allowed to dry for 1 h before the start of the experiment to permit the evaporation of the solvent.
4.4. Aphid Probing Behavior
Myzus persicae probing behavior was monitored by using the Electrical Penetration Graph (EPG)
technique. The EPG technique provides a unique opportunity to reveal aphid mouthparts stylets
activities in plant tissues [41–43]. The parameters describing aphid behavior during probing and
feeding, such as total time of probing, duration and frequency of sap ingestion periods, number of
probes, etc., are good indicators of plant suitability or interference of probing by chemical or physical
factors in individual plant tissues [16
–20]. In this experimental setup, aphid and plant are made parts
of an electric circuit, which is completed when the aphid inserts its stylets into the plant. Weak voltage

Molecules 2020, 25, 3185
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is supplied in the circuit, and all changing electric properties are recorded as EPG waveforms that have
been correlated with aphid activities and stylet position in plant tissues [42,43].
In the present study, one- to seven day old adult apterous females of M. persicae and three week
old plants with four to five fully developed leaves were used for all experiments according to the
standard procedure applied in similar studies [17
electrode with conductive silver paint and starved for 1 h prior to the experiment. Probing behavior of
apterous M. persicae was monitored for 8 h continuously with a Giga-8 DC EPG with 1 G of input
–20,24–27]. Aphids were attached to a golden wire
Ω
resistance (EPG Systems, Wageningen, The Netherlands) and Stylet+ software (www.epgsystems.eu).
Each aphid was given access to a freshly prepared leaf of an unused plant, which means that each
plant and each aphid were used only once. One aphid–plant combination was considered a replication.
Two rounds of 8 replications (n = 16) were carried out for each studied substance and control. Giga-8
DC EPG allows the recording of 8 samples simultaneously. Incomplete EPG recordings, i.e., those that
were prematurely ended due to the aphid falling off the plant or other incidents, were discarded from
analysis. All experiments were carried out under the same conditions of temperature, relative humidity,
and photoperiod, as described for the rearing of plants and aphids. The bioassays started at 10–11 a.m.
MEST (Middle European Summer Time).
The following aphid behaviors related to mouthparts positions in or out of the plant tissues
were distinguished: non-probing, which represents aphid stylets outside the plant tissues, pathway
phase ‘C’, which represents the movement of aphid stylets within the epidermis and mesophyll; phase
‘F’, which represents unidentified (‘derailed’) stylet movements within apoplast; xylem phase ‘G’,
which represents active xylem sap uptake; phloem phase consisting of watery salivation E1 and passive
ingestion of phloem sap ‘E2’. ‘F’ and ‘G’ occurred sporadically irrespective of a treatment, therefore,
these activities were analyzed together with phase ‘C’ and referred to as the ‘non-phloem’ phase
of probing.
4.5. Statistical Analysis
The EPG parameters describing aphid probing behavior were calculated manually and individually
for every aphid and the means and standard deviations were subsequently calculated using the EPG
analysis Excel worksheet created for this study. Two comparative analyses were carried out. First,
aphid behavior on control plants was compared to aphid behavior on naringenin- and naringenin
derivatives-treated plants individually for each compound/treatment. This comparison (Mann–Whitney
U-test) was performed and the results were interpreted to reveal the mode of action of a given compound
(deterrent, attractant, neutral), which allowed grouping of the studied compounds according to their
similarity in the effect they had on aphid behavior. A second comparison was carried out to determine
the effect of structural modifications in the naringenin molecule on the aphid behavior modifying
activity. For this purpose, aphid behavior on only the treated plants was compared. Due to failure to
meet the assumptions of analysis of variance, the obtained data were analyzed by the Kruskal–Wallis
test and post hoc multiple comparisons of mean ranks for all groups (Dunn’s test). The Kruskal–Wallis
test is a non-parametric alternative to the one-factor ANOVA test for independent measures and it is
commonly used to analyze data deriving from EPG recordings of aphid probing [32]. The mean and
SD values given in Tables 1–3 are a representation of non-Gaussian data, but the statistical analysis was
done by non-parametric tests, in which all individual data were included. All statistical calculations
were performed using StatSoft, Inc. (2014) STATISTICA (data analysis software system, version 12,
www.statsoft.com).
Author Contributions: Conceptualization, B.G. and M.A.; Methodology, B.G., M.A. and B.K.; Formal Analysis,
A.W.-K.; Investigation, K.S.; A.W.-K.; B.K.; M.A. and J.K.; Data Curation, B.G. and M.A.; Writing-Original Draft
Preparation, B.G. and M.A.; Writing-Review & Editing, B.G.; Visualization, K.S. and M.A.; Supervision, B.K.; B.G.
and M.A.; Funding Acquisition, M.A. and B.K. All authors have read and agreed to the published version of
the manuscript.

Molecules 2020, 25, 3185
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Funding: Publication was supported by the National Science Centre, Grant No. 2016/21/B/NZ9/01904. The project
was financially supported by Minister of Science and Higher Education in the range of the program entitled
“Regional Initiative of Excellence” for the years 2019-2022, Project No. 010/RID/2018/19, amount of funding
12.000.000 PLN.
Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design of the
study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to
publish the results.
References
1.
2.
3.
4.
5.
6.
Venkateswara, R.P.; SDVS, K.; Rohini, P.; Bhagyasree, P. Flavonoid: A review on naringenin.
J. Pharmacogn. Phytochem. 2017, 6, 2778–2783.
Khan, M.K.; Zill-E-Huma, O.; Dangles, O. A comprehensive review on flavanones, the major citrus
polyphenols. J. Food Compos. 2014, 33, 85–104. [CrossRef]
Patton, C.A.; Ranney, T.G.; Burton, J.D.; Walgenbach, J.F. Feeding responses of japanese beetle to naturally
occurring metabolites found in rosaceous plants. J. Environ. Hort. 1997, 15, 222–227.
Su, Q.; Zhou, Z.; Zhang, J.; Shi, C.; Zhang, G.; Jin, Z.; Wang, W.; Li, C. Effect of plant secondary metabolites
on common cutworm, Spodoptera litura (Lepidoptera: Noctuidae). Entomol. Res. 2017, 48, 18–26. [CrossRef]
Riddick, E.W.; Wu, Z.; Eller, F.J.; Berhow, M.A. Do bioflavonoids in Juniperus virginiana heartwood stimulate
oviposition in the ladybird Coleomegilla maculata? Int. J. Insect Sci. 2018, 10, 1–13. [CrossRef] [PubMed]
Hernandez, I.G.; Palottini, F.; Macri, I.; Galmarini, C.R.; Farina, W.M. Appetitive behavior of the honeybee
Apis mellifera in response to phenolic compounds naturally found in nectars. J. Exp. Biol. 2019, 222, 189910.
[CrossRef]
7.
Wellings, P.W.; Ward, S.A.; Dixon, A.F.G.; Rabbinge, R. Crop Loss Assessment. In Aphids, Their Biology,
Natural Enemies and Control; Minks, A.K., Harrewijn, P., Eds.; Elsevier: Amsterdam, The Netherlands, 1989;
Volume C, pp. 49–64.
8.
9.
Blackman, R.L.; Eastop, V.F. Aphids on the World’s Crops: An Identification Guide; John Wiley and Sons:
Chichester, UK; New York, NY, USA; Brisbane, Australia; Toronto, Japan; Singapore, 1985.
Goławska, S.; Sprawka, I.; Łukasik, I.; Goławski, A. Are naringenin and quercetin useful chemicals in
pest-management strategies? J. Pest. Sci. 2014, 87, 173–180. [CrossRef]
10. Dedryver, C.A.; Le Ralec, A.; Fabre, F. The conflicting relationships between aphids and men: A review of
aphid damage and control strategies. C. R. Biol. 2010, 333, 539–553. [CrossRef]
11. Bass, C.; Puinean, A.M.; Zimmer, C.T.; Denholm, I.; Field, L.M.; Foster, S.P.; Gutbrod, O.; Nauen, R.;
Slater, R.; Williamson, M.S. The evolution of insecticide resistance in the peach potato aphid, Myzus persicae.
Insect Biochem. Mol. Biol. 2014, 51, 41–51. [CrossRef]
12. Blake, R. Eu Neonicotinoid Ban Removes Vital Tools in Global Fight Against Pests. Outlooks Pest Manag.
2018, 29, 197–200. [CrossRef]
13. Pickett, J.A. Lower terpenoids as natural insect control agents. In Ecological Chemistry and Biochemistry of
Plant Terpenoids; Harborne, J.B., Tomas-Barberan, F.A., Eds.; Clarendon Press: Oxford, UK, 1991; pp. 297–313.
14. Dayan, F.E.; Cantrell, C.l.; Duke, S.O. Natural products in crop protection. Bioorg. Med. Chem. 2009, 17,
4022–4034. [CrossRef] [PubMed]
15. Lattanzio, V. Phenolic compounds: Introduction. In Natural Products; Ramawat, K.G., Me’rillon, J.M., Eds.;
Springer: Berlin/Heidelberg, Germany, 2013; pp. 1543–1580.
16. Powell, G.; Hardie, J.; Pickett, J. Effects of the antifeedant polygodial on plant penetration by aphids, assessed
by video and electrical recording. Entomol. Exp. Appl. 1993, 68, 193–200. [CrossRef]
17. Wróblewska-Kurdyk, A.; Gniłka, R.; Dancewicz, K.; Grudniewska, A.; Wawrzen´czyk, C.; Gabrys´, B. β-thujone
and its derivatives modify the probing behavior of the peach potato aphid. Molecules 2019, 24, 1847.
[CrossRef]
18. Wróblewska-Kurdyk, A.; Dancewicz, K.; Gliszczyn´ska, A.; Gabrys´, B. New insight into the behaviour
modifying activity of two natural sesquiterpenoids farnesol and nerolidol towards Myzus persicae (Sulzer)
(Homoptera: Aphididae). Bull. Entomol. Res. 2020, 110, 249–258. [CrossRef]
19. Gabrys´, B.; Dancewicz, K.; Gliszczyn´ska, A.; Kordan, B.; Wawrzen´czyk, C. Systemic deterrence of aphid
probing and feeding by β-damascone analogues. J. Pest. Sci. 2015, 88, 507–516. [CrossRef] [PubMed]

Molecules 2020, 25, 3185
12 of 13
20. Stompor, M.; Dancewicz, K.; Gabrys´, B.; Anioł, M. Insect antifeedant potential of xanthohumol,
isoxanthohumol, and their derivatives. J. Agric. Food Chem. 2015, 63, 6749–6756. [CrossRef]
21. Shelton, A.M.; Badenes-Perez, F.R. Concepts and applications of trap cropping in pest management.
Annu. Rev. Entomol. 2006, 51, 285–308. [CrossRef]
22. Fereres, A. Barrier crops as a cultural control measure of non-persistently transmitted aphid-borne viruses.
Virus Res. 2000, 71, 221–231. [CrossRef]
23. Cook, S.M.; Khan, Z.R.; Pickett, J.A. The use of push-pull strategies in integrated pest management.
Annu. Rev. Entomol. 2007, 52, 375–400. [CrossRef]
24. Grudniewska, A.; Dancewicz, K.; Białon´ska, A.; Ciunik, Z.; Gabrys´, B.; Wawrzen´czyk, C. Synthesis of
piperitone-derived halogenated lactones and their effect on aphid probing, feeding, and settling behavior.
RSC Adv. 2011, 1, 498–510. [CrossRef]
25. Paprocka, M.; Gliszczyn´ska, A.; Dancewicz, K.; Gabrys´, B. Novel hydroxy- and epoxy-cis-jasmone and
dihydrojasmone derivatives affect the foraging of the peach potato aphid Myzus persicae (Sulzer) (Homoptera:
Aphididae). Molecules 2018, 23, 2362. [CrossRef] [PubMed]
26. Dancewicz, K.; Gabrys´, B.; Dams, I.; Wawrzen´czyk, C. Enantiospecific effect of pulegone and pulegone
−
derived lactones on settling and feeding of Myzus persicae (Sulz.). J. Chem. Ecol. 2008, 34, 530–538. [CrossRef]
[PubMed]
27. Dancewicz, K.; Sznajder, K.; Załuski, D., Kordan; Gabrys´, B. Behavioral sensitivity of Myzus persicae to
volatile isporenoids in plant tissues. Entomol. Exp. Appl. 2016, 160, 229–240. [CrossRef]
28. Gabrys´, B.; Pawluk, M. Acceptability of different species of Brassicaceae as hosts for the cabbage aphid.
Entomol. Exp. Appl. 1999, 91, 105–109. [CrossRef]
29. Grudniewska, A.; Dancewicz, K.; Białon´ska, A.; Wawrzen´czyk, C.; Gabrys´, B. Piperitone-derived saturated
lactones: Synthesis and aphid behavior-modifying activity. J. Agric. Food Chem. 2013, 61, 3364–3372.
[CrossRef]
30. Tjallingii, W.F. Regulation of phloem sap feeding by aphids. In Regulatory Mechanisms in Insect Feeding;
Chapman, R.F., de Boer, G., Eds.; Chapman & Hall: New York, NY, USA, 1995; pp. 190–209.
31. Mayoral, A.M.; Tjallingii, W.F.; Castanera, P. Probing behavior of Diuraphis noxia on five cereal species with
different hydroxyamic acid levels. Entomol. Exp. Appl. 1996, 78, 341–348. [CrossRef]
32. Philippi, J.; Schliephake, E.; Jurgens, H.U.; Jansen, G.; Ordon, F. Feeding behavior of aphids on narrow-leafed
lupin (Lupinus angustifolius) genotypes varying in the content of quinolizidine alkaloids. Entomol. Exp. Appl.
2005, 156, 37–51. [CrossRef]
33. Schwarzkopf, A.; Rosenberger, D.; Niebergall, M.; Gershenzon, J.; Kunert, G. To feed or not to feed: Plant
factors located in the epidermis, mesophyll, and sieve elements influence pea aphid’s ability to feed on
legume species. PLoS ONE 2013, 8, e75298. [CrossRef]
34. Ververidis, F.; Trantas, E.; Douglas, C.; Vollmer, G.; Kretzschmar, G.; Panopoulos, N. Biotechnology of
flavonoids and other phenylpropanoid-derived natural products. Part I: Chemical diversity, impacts on
plant biology and human health. Biotechnol. J. 2007, 2, 1214–1234. [CrossRef]
35. Prado, E.; Tjallingii, W.F. Aphid activities during sieve element punctures. Entomol. Exp. Appl. 1994, 72,
157–165. [CrossRef]
36. Powell, G.; Pirone, T.; Hardie, J. Aphid stylet activities during potyvirus acquisition from plants and in vitro
system that correlate with subsequent transmission. Eur. J. Plant Pathol. 1995, 101, 411–420. [CrossRef]
37. Martin, B.; Collar, J.L.; Tjallingii, W.F.; Fereres, A. Intracellular ingestion and salivation by aphids may
cause the acquisition and inoculation of non-persistently transmitted plant viruses. J. Gen. Virol. 1997, 78,
2701–2705. [CrossRef] [PubMed]
38. Brault, V.; Uzest, M.; Monsion, B.; Jacquot, E.; Blanc, S. Aphids as transport devices for plant viruses.
C. R. Biol. 2010, 333, 524–538. [CrossRef]
˙
39. Kozłowska, J.; Potaniec, B.; Zarowska, B.; Anioł, M. Synthesis and biological activity of novel O-alkyl
derivatives of naringenin and their oximes. Molecules 2017, 22, 1485. [CrossRef]
40. Polonsky, J.; Bhatnagar, S.C.; Griffiths, D.C.; Pickett, J.A.; Woodcock, C.M. Activity of qassinoids as
antifeedants against aphids. J. Chem. Ecol. 1989, 15, 933–998. [CrossRef] [PubMed]
41. Halarewicz-Pacan, A.; Gabrys´, B.; Dancewicz, K.; Wawrzen´czyk, C. Enantiospecific effect of limonene and
limonene-derived bicyclic lactones on settling and probing behaviour of the peach-potato aphid Myzus persicae
(Sulz.). J. Plant Prot. Res. 2003, 43, 133–142.

Molecules 2020, 25, 3185
13 of 13
42. Pettersson, J.; Tjallingii, W.F.; Hardie, J. Host-plant selection and feeding. In Aphids as Crop Pests;
van Emden, H.F., Harrington, R., Eds.; CABI: Wallingford, UK, 2017; pp. 173–195.
43. Tjallingii, W.F.; Hogen Esch, T.H. Fine-structure of aphid stylet routes in plant-tissues in correlation with
EPG signals. Physiol. Entomol. 1993, 18, 317–328. [CrossRef]
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