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Population dynamics and economic losses caused by Zeuzera pyrina, a cryptic wood-borer moth, in an olive orchard in Egypt

Authors:
  • Swedish University of Agricultural Sciences /Sveriges Lantbruksuniversitet (SLU)
  • Plant Protection Research Institute

Abstract and Figures

The leopard moth Zeuzera pyrina L. (ZP) is an invasive pest from Europe of increasing significance in North Africa, in particular for olive cultivation. We followed the temporal dynamics by combined light/pheromone trapping over a 10-year period (2002–2011) in a 240-ha olive farm in Northern Egypt.The ZP had an annual cycle with one or two peak flights, from late April until October. Time series analysis showed a 2-year cycle of trap catch. This cycle is likely related to the ‘on/off’ bearing pattern of the olive, where years of high and low yield are observed to alternate.Larval damage in both ‘on’ and ‘off’ years in the infested trees gave fruit yield losses of 37–42%. The loss was estimated to 2.1–4.8 t/ha among susceptible varieties. The relative losses were the same during on and off years.Infestation of four susceptible and five resistant olive cultivars in different cropping systems varied within and between adjacent plots. The results suggest less infestation by intercropping of resistant varieties, which could assist in ZP management.Both temporal and spatial dynamics strongly influence population dynamics and the dynamics are related to variation in the moth host plant.
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Agricultural and Forest Entomology (2015), 17,919 DOI: 10.1111/afe.12075
Population dynamics and economic losses caused by Zeuzera
pyrina, a cryptic wood-borer moth, in an olive orchard in Egypt
Esmat Hegazi,FredrikSchlyter
, Wedad Khafagi, Atwa Atwa§¶, Essam Agamy∗∗ and Maria Konstantopoulou††
Department of Entomology, Faculty of Agriculture, Alexandria University, 542245, Aaton Str., Alexandria, Egypt, Unit of Chemical Ecology,
Department of Plant Protection Biology, Swedish University of Agricultural Sciences, PO Box 102, SE-230 53 Alnarp, Sweden, Biological Control,
Plant Protection Research Institute, 3236, Bacoos, Alexandria, Egypt, §Plant Protection Research Institute, 77688, Nadi El Seid Str., Cairo, Egypt,
King Abdul-Aziz University, Jeddah, Kingdom of Saudi Arabia, ∗∗ Department of Entomology, Faculty of Agriculture, Cairo University, Cairo, Egypt,
and ††Chemical Ecology and Natural Products Laboratory, NCSR ‘Demokritos’, 15310, Paraskevi Str., Attikis, Greece
Abstract 1 The leopard moth Zeuzera pyrina L. (ZP) is an invasive pest from Europe of increasing
signicance in North Africa, in particular for olive cultivation. We followed the
temporal dynamics by combined light/pheromone trapping over a 10-year period
(20022011) in a 240-ha olive farm in Northern Egypt.
2 The ZP had an annual cycle with one or two peak ights, from late April until October.
Time series analysis showed a 2-year cycle of trap catch. This cycle is likely related to
the ‘on/off’ bearing pattern of the olive, where years of high and low yield are observed
to alternate.
3 Larval damage in both ‘on’ and ‘off’ years in the infested trees gave fruit yield losses
of 3742%. The loss was estimated to 2.1– 4.8 t/ha among susceptible varieties. The
relative losses were the same during on and off years.
4 Infestation of four susceptible and ve resistant olive cultivars in different cropping
systems varied within and between adjacent plots. The results suggest less infestation
by intercropping of resistant varieties, which could assist in ZP management.
5 Both temporal and spatial dynamics strongly inuence population dynamics and the
dynamics are related to variation in the moth host plant.
Keywords ARIMA, leopard moth, olive, periodic oscillations, population dynamics,
Zeuzera pyrina.
Introduction
The olive tree (Olea europea L.) plays an important part in the
lives of Mediterranean people. Its role is multiple: nutritional,
social, cultural, economic and political. The key insect pests
of Mediterranean olives are the olive fruit y Bactrocera oleae
(Gmelin), the olive moth Prays oleae (Bernard), and the black
scale Saissetia oleae (Olivier). However, another insect pest, the
leopard moth Zeuzera pyrina L. (ZP) (Lepidoptera: Cossidae),
has become of increasing impact in North Africa in the last
few decades (Katsoyannos, 1992). Little is known of its ecol-
ogy in this new context. The larvae of ZP are cryptic wood-
borers affecting a wide variety of trees and shrubs, comprising
over 150 plant species from 20 genera (Balachowsky & Mesnil,
1935; Carter, 1984; Castellari, 1986; Gratwick, 1992; Kutinkova
Correspondence: Esmat Hegazi. Tel.: +2 (3) 5908497; fax: +2(3)
5922780; e-mail: eshegazi@hotmail.com
et al., 2006). Newly-established olive orchards suffer the great-
est damage, including the death of young trees. In nurseries, the
damage can be particularly extensive (Liotta & Giuffrida, 1967;
Castellari, 1986). In Egypt, damage caused by ZP led to uproot-
ing of olive groves by growers (E. Hegazi, unpublished data).
The damage caused by the larval tunnels in structurally critical
wood can be extremely serious to a tree already bearing a fruit
load; it causes ordinary branches to break under a medium load,
whereas it may cause complete death of young trees with a heavy
load as a result of damage to the major branches and trunk.
Monitoring and control of this cryptic moth is extremely
difcult because the larvae bore deep into twigs, branches and
trunks. Visual inspection of larval activity has been used as
main method of monitoring this pest (Kutinkova et al., 2006).
However, night-active adult moths are difcult to observe in the
eld. Many moth pests of agricultural importance are commonly
monitored using pheromone traps (Durant et al., 1986; Delisle,
1992), although other monitoring techniques such as black-light
traps are also used (Steinbauer, 2003; Szabo et al., 2007).
© 2014 The Royal Entomological Society
10 E. Hegazi et al.
Methods of monitoring ZP adults by using pheromone-baited
traps have been investigated (Tonini et al., 1986; Pasqualini
et al., 1992; Pasqualini & Natale, 1999). There are, however,
some limitations with respect to using light (Blomberg et al.,
1976; Baker & Sadovy, 1978) or pheromone traps (Malo et al.,
2001) alone. Light traps are less competitive than calling females
with respect to capture males, whereas pheromone traps do not
capture females. The available data on the ight phenology and
biology of ZP in Egypt are scarce and often contradictory (Ismail
et al., 1992). Hence, we have used trapping stations combining
pheromone and black light trapping (Hegazi et al., 2009)
In our study area, a major outbreak of ZP occurred in July to
October 2001, causing massive damage. Of the 240-ha planta-
tion, 12 ha were severely infested by ZP and the owner had a
plan to uproot this area. Initiation of insect outbreaks is poorly
understood. Factors causing such outbreaks remain enigmatic as
a result of the requirement for many years of data, as well as the
examination of detailed mechanisms (Maron et al., 2001; Nel-
son et al., 2013). In addition, the olive has a strong year-to-year
deviation cycle in yield, known as ‘on/off’ years (Lavee, 2007).
This alternate bearing is highly dependent on the climate in
each growing region (Morettini, 1950; Hartmann, 1951). These
distinct ‘on/off’ years in the host tree are expected to co-vary
with the population dynamics of the moth, although no details
are known.
In the present study, we aimed to investigate relevant aspects
of the population dynamics and the impact of this upcoming
pest in North Africa, leading to an improved integrated pest
management of this invasive pest.
We document the population dynamics on seasonal and yearly
scales by full season pheromone and black light trapping (Hegazi
et al., 2009) for the months of April to November over 10years,
including ve pairs of ‘on/off’ years. The dynamics are modelled
by an autoregressive integrated moving average (ARIMA) time
series. Intensive damage records (visual) and loss estimates
(grower’s data) were recorded for 2years for estimates of
economic loss, in addition to a 1-year study of infestation at
different scales of variety intercropping.
Materials and methods
Experimental fields
The present study was conducted in a commercial olive farm
(Fig. 1) with drip-irrigation, located in the arid growing area
between Alexandria and Cairo (305121′′E; 300827′′ N),
177 km south of Alexandria, 60 km north of Cairo. The farm
(240 ha, 336 trees/ha) is divided into 88 plots (3.0 –3.5 ha, each
comprising two varieties/plots) isolated by windbreak hedges.
The olive trees were 11– 12 years old, 3– 4 m in height, planted
at a distance of 5 m along the row and 6 m between rows.
The principal cultivars of table olives at the orchard (61 774
olive trees) were Picual representing approximately 27.2%,
Manzanello representing approximately 26.1% and Toffahi
representing approximately 12.4%. Less than 10% were found
for six cultivars; Kalamata, Akss, Sennara,Dolcie,Hamed and
Shami, representing approximately 8.1%, 6.2%, 5.8%, 5.3%,
4.7% and 4.2%, respectively, of the total bearing. Varieties
considered as susceptible (Hegazi & Khafagi, 2005) are shown
in italics.
Each quadratic plot was divided into 10 sectors or ‘strips’,
each comprising approximately 30 trees. Each strip combined
three lines of one cultivar alternating with another strip of three
lines of the second cultivar, and so on, in a ‘strip intercropping
system’. Thus, the width of each strip was similar. It was
established in 1996, drip irrigated and not in close proximity to an
apple plantation or other known host plants of ZP grown within
15 km, and only palm trees and naturally occurring wild plants
were nearby.
No chemical control was applied on monitoring or experimen-
tal plots during the experimental period. The arid climate (data
for 2006–2009) comprised rainy seasons lasting from Novem-
ber /December to January/February with a mean annual rainfall
of 9.2 mm. The mean monthly minimum temperature varied from
10.2 C in January to 23.9 C in August and the mean monthly
maximum temperature varied from 18.9 C in January to 35.6 C
in July. The mean relative humidity ranged from 47.8% in April
to 63.8% in January.
Detection of infested trees, natural enemies and larval
phenology
Infestations were recognized (Fig. 2) by the presence of (i) cylin-
drical yellowish to brown excrement pellets in bark crevices,
around the entrance of larval tunnels and on the ground; (ii) pro-
truding empty pupal skins on the infested parts by ZP, indicating
the emergence of moths from larval tunnels; (iii) several partly
broken branches as a result of fruit load and wind mechanical
damage with dead brown foliage hanging in tree crowns, char-
acteristic of heavy infestation; and (iv) secreting gum near the
infested parts. In September 2007 and 2009, we collected lar-
vae during this larval monitoring for quantication of parasitoid
incidence.
Phenology of larvae was investigated by careful eld dissection
of branches, twigs and trunks of heavily-infested trees in the late
and early 2010 and 2011 olive seasons, respectively, to estimate
larval abundance in relation to spring ight period of the moths.
Trapping for temporal variation
To study the population cycles, the ight phenology of the adult
leopard moth was studied for 10 consecutive seasons with an
ultraviolet– light pheromone sticky trap combination (Fig. 1C)
(Hegazi et al., 2009). Five traps (one trap every 3 ha) were used
per season in plots that combined susceptible olive varieties
(Toffahi, as well as Sennara or Sennara and Hamed). Each trap
was baited with pheromone dispenser (Fersex ZP; SEDQ, Spain).
The main components of the product are: (E,Z)-2,13-octadecenyl
acetate and (E,Z)-3,13-octadecenyl acetate. For each trap, a
hollow metal stake was placed in the ground of the selected
area. A wooden pole of a slightly smaller diameter than the
hollow metal stake was cut to the appropriate height and slipped
inside the metal stake. The trap was mounted on the top of the
wooden pole. The hollow metal stakes acted as rat guard (i.e.
to prevent rats from climbing up to the trapping insects). Trap
height was adjusted to 50– 100cm above the level of the canopy.
Light was run from sunrise to sunset only. The distance between
traps was >200 m. The position of the traps was switched
at each visit to minimize the possible effects of microhabitat
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
Population cycles of Z. pyrina 11
(A) (C)
(B)
Figure 1 (A) The olive farm from satellite view. (B) Close up of part of the olive farm from satellite. A and B imagery from Google Earth
(http://www.google.com/earth/). (C) The pheromone-light trap.
structure between the plots and rebaited with fresh dispensers
every 40 days. Trapping was initiated in mid-April and ended
in the second week of November of each season. Trap captures
of male and female moths of ZP were counted every other day
during which the sticky pad was changed. Data are presented as
mean catches/trap per week or per month for additional detail.
Females were carefully dissected to determine their reproductive
state.
Yield and economic losses
In 2006 and 2007, efforts were made at the experimental farm to
ensure uniform ZP infestation plots by using highly susceptible
local varieties (Toffahi and Sennara/plot) and adjusting both the
time of fertilizer application and irrigation, keeping the exper-
imental plots free of chemical or mechanical insect control to
document the level of damage by an unmanaged ZP infestation.
The design could use only two naturally severely injured olive
plots with ZP with plantings of susceptible local olive varieties
(Sennara & Toffahi) exactly similar to those available in this part
of the olive farm in the 2006 and 2007 olive seasons. There is a
drawback to this design because only two plots were included,
although the 15-fold sampling of each variety and the natural
presence of infested and uninfested trees ensured sufcient and
some degree of independent variation of observations. However,
only the effect of the infested/uninfested categories can be for-
mally tested without pseudoreplication (Hurlbert, 2009) and not
the direct effects of the different susceptibility of varieties.
Economic losses as a result of ZP were measured based
on actual yield losses. Crop loss can be dened (de Groote,
2002) as the difference between the actual yield by the infested
trees and the potential yield or, more precisely, as the yield
that would have been obtained in the absence of the pest
under study, estimated from ‘apparently uninfested trees’. Two,
3-ha naturally badly infested olive plots with leopard moth
planted with the same susceptible local varieties/plot (Sennara
and Toffahi) were selected to study the economic loss caused
by the pest for two successive years (2006 & 2007). All
trees/variety/sector were checked every other week from July
until late September to record the presence of active tunnels of
ZP larvae, the number of broken branches bearing fruit and the
observed tunnels marked. In each inspection, fruit weight/broken
branches (infested) was also recorded. At harvest time, trees
were classied into infested and apparently uninfested. Severely
(i.e. with extensive signs of injury) or moderately injured trees
(three to six broken limbs) as a result of ZP larvae were
considered as infested. Dead or fruit-free trees (9%) were
not included. At harvest time, the fruit yield of three trees
of both infested and apparently uninfested/sector (i.e. each,
3trees×5 sectors =15 trees/variety/plot =120 trees/season) was
selected randomly to estimate the real fruit yield/tree.
The real fruit yield (Yr)=yield of infested trees +yield of
uninfested trees.
The theoretical or ‘potential yield’/sector (Yp) =number of
trees/sector ×mean of fruit weight/uninfested tree of the same
sector.
The difference between real and theoretical yield gives the crop
loss weight (LW):
YpYr=Lw(1)
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
12 E. Hegazi et al.
(A) (B) (C)
(D) (E) (F) (G) (H)
Figure 2 (A) Badly infested tree by Zeuzera pyrina (ZP). (B) Larval tunnel in broken branch. (C) Branch of susceptible tree containing 21 ZP larvae. (D)
Protruding empty pupal skins indicating the emergence of ZP moth. (E) Secreting gum near the infested parts. (F) Emergence hole of larval tunnel. (G)
Yellowish to brown faecal pellets. (H) Low fruiting yield of infested tree.
Multiplication of crop loss with the price of olive fruits per
weight ($W) gives the economic loss (LE) of ZP per area
(Table 1):
Lw×$W=LE(2)
Spatial variation of infestation and yield
After making informal observations during 2006 and 2007
indicating a possible lower infestation in susceptible-variety
plots near resistant-variety plots, we made a small study of
spatial variation of infestation. In 2009, six target plots, each
comprising 3-ha naturally-infested olive plots with ZP planted
with olives varying in their tolerance to ZP, were selected to
study the possible effects of variety intercropping [i.e. some were
susceptible (S) and some were resistant (R)] (i.e. variety mixtures
in target plots as S +S, S +R, R +R). In addition, each treatment
plot had ‘pure’ neighbouring plots of only resistant (RR) or
susceptible (SS) trees on both sides (Table 2). All trees of each
target plot were inspected for activity of the cryptic larvae every
other week, as described above. At harvest time, trees of each plot
were classied into apparently uninfested, moderately infested
(less than six broken branches/tree) and severely (more than eight
broken branches/tree) infested trees. The fruit yield of six trees
of each category for each variety/target plot was harvested and
weighed.
The number and combination types of resistant and suscep-
tible varieties pairs did not allow for a full factorial analysis
of variance (), testing for both the effect of the identity
of varieties inside target plots and the inuence of resistant
or susceptible neighbours on the infestation rate (Table 2).
However, without resorting to pseudoreplication (Hurlbert,
2009), we could contrast the inuence of neighbouring plots
(RR- or SS-types) on yield loss in target plots that had at least
one resistant variety (R +RorR+S). The restriction of pos-
sible contrasts was a result of the paucity of target plots with
S-varieties present.
Statistical analysis
Trapping counts were analyzed for cyclic patterns at different
multi-annual levels by ARIMA time series algorithms (Yaffee &
McGee, 2000) using  , version 19 (IBM Corp., Armonk,
New York) with procedures TSMODEL and TSPLOT. This
type of model is only a statistical tting to data and does not
address any biological detail of the population dynamics such
as rates of birth or deaths as in a population dynamics-based
model (Turchin, 2013). ARIMA time series models are the most
general class of models for forecasting a time series that can
be stationarized by transformations such as differencing and
logging (Yaffee & McGee, 2000). This type of model can be
seen as a ne-tuned version of random-walk models, where
the ne-tuning consists of adding lags of the differenced series
and/or lags of the forecast errors to the prediction equation, as
needed to remove any last traces of autocorrelation from the
forecast errors. The numerical outputs of the ARIMA models
are not given in the results; instead, only the corresponding
auto-correlation function (ACF) and partial ACF (PACF) plots
are provided, which give visual information on the best supported
population cycle lengths obtained from the data by the models.
We included an estimate of the yearly trapping total for the rst
‘outbreak’ in 2001 to gain an 11-year series allowing analysis
of somewhat longer cycles. The added conservative estimate for
2001 was found by rounding up to the one-signicant digit higher
value compared with the 2009 total, because 2001 was observed
to have a clearly higher damage magnitude.
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
Population cycles of Z. pyrina 13
Tabl e 1 Economic losses in local susceptible olive cultivars caused by Zeuzera pyrina in two plots estimated under natural infestation in ‘high-fruiting
year’ 2006 and ‘low-fruiting year’ 2007
Infested trees Apparently uninfested trees Losses/hac
Trees Limb fruit Fruit yield Trees Yield Real yield Theoretical
Plot Variety Number loss(t) Total (t) Per tree (kg) Number Total (t) Per tree (kg) (Yr)a(t) yield (Yp)b(t) LW(t) LE($)
Season 2006
1 Sennara 163 1.3 5.6 34.9±1.7 227 12.5 56.7 ±4.8 18.1 22.1 3.1 1800
Toffahi 239 2.3 7.4 31.6±2.1 151 8.2 55.0 ±3.5 15.7 21.4 4.8 3200
2 Sennara 127 0.6 4.5 35.2±2.8 263 15.8 61.0 ±3.9 20.3 23.8 2.8 1700
Toffahi 119 0.8 4.3 37.1±2.8 271 16.1 59.5 ±3.3 20.5 23.2 2.3 1500
Season 2007
1 Sennara 161 0.6 4.8 29.6±1.5 229 11.7 51.0 ±1.3 16.4 19.9 2.9 1700
Toffahi 162 0.8 4.5 28.5±2.2 228 10.8 47.1 ±1.8 15.3 18.4 2.6 1700
2 Sennara 143 0.6 3.9 27.7±2.8 247 11.9 48.6 ±1.5 15.9 18.9 2.6 1500
Toffahi 134 0.7 4.0 28.7±2.6 256 12.1 47.3 ±1.2 16.0 18.4 2.1 1400
aThe harvest of infested and non-infested trees, based on the samples of 15 trees/variety/plot.
bThe theoretical or potential yield (Yp) is calculated as number of trees ×mean yield of uninfested trees (per variety and plot).
cWeight of crop loss (LW) and economic loss (LE) is the difference between Ypand Yrand the product of LWand price per weight ($W), in accordance
with Eqns 1 and 2, respectively (see Materials and methods).
Tabl e 2 Infestation rate (%) and yield losses in target olive plots and the effect thereon of neighbouring plots with different combinations of susceptible
and resistant olive trees in 2009
Target plot fruit yield/tree (kg)
Target plot’s
cultivarsa
Infestation rate
(%)b
Apparently
non-infested
Moderately
infested
Severely
infested Mean/infested tree Loss (t/ha)
Olive cultivars of
neighbouring plotsc
Picual (R) 0.0 49.0 ±4.3 0.0 0.0 0.0 0.0 RR ‘Dolcie & Shami’
Manzanello (R) 0.0 59.0 ±4.3 0.0 0.0 0.0 0.0
Dolcie (R) 0.0 80.0 ±3.5 0.0 0.0 0.0 0.0 RR ‘Dolcie & Kalamata’
Kalamata (R) 0.0 26.4 ±2.7 0.0 0.0 0.0 0.0
Picual (R) 8.2 37.6 ±2.5 10.2 ±1.6 0.7 ±0.3 5.4 ±1.7 0.9 SS ‘Toffahi & Sennara’
Manzanello (R) 10.3 45.0 ±3.5 13.0 ±2.1 0.6 ±0.4 6.8 ±2.3 1.3
Shami (R) 9.1 55.0 ±3.5 18.6 ±1.9 2.8 ±0.9 10.7 ±2.8 1.4 SS ‘Hamed & Sennara’
Toffahi (S) 18.9 81.0 ±4.3 26.4 ±2.7 0.0 13.2 ±4.6 4.3
Kalamata (R) 11.1 26.6 ±2.6 11.0 ±1.2 0.0 5.5 ±1.9 0.8 SS ‘Toffahi & Sennara’
Toffahi (S) 17.5 75.0 ±3.5 20.2 ±1.8 1.1±0.6 10.6 ±3.3 3.8
Sennara (S) 25.3 67.0 ±4.6 19.4±1.7 3.6 ±1.2 11.5 ±2.8 4.7 SS ‘Toffahi & Sennara’
Hamed (S) 39.8 16.0 ±1.4 3.6±0.8 0.1 ±0.1 1.8 ±0.7 1.9
aType of variety in plot: S, susceptible; R, resistant.
bTarget plots are sorted by mean target plot infestation rate of the two target plot cultivars.
cType of variety of neighbouring plots: SS, both cultivars susceptible; RR, both cultivars resistant.
The eld surveys were conducted using a complete random-
ized block design and data were subjected to  (SAS,
2000). Data are presented as the means of moth catches and fruit
yield/tree. Means were normalized using log(x+0.5) transfor-
mation to increase variance homogeneity. For the infestation rate,
we had to use nonparametric statistics as a result of the many zero
values.
Results
Trapping study: within and between years variation
Moth catches and larval phenology. Monthly catches in
light-pheromone traps for ZP, over the period 2002–2011,
are presented in Fig. 3. The rst capture occurred during late
April or early May and then continuously from May throughout
the growing season until mid-November (i.e. moths were present
all season). The population trends of ZP showed one annual
peak in some years (2005, 2008 and 2009) and two peaks in
most years. Moth emergence takes place from late April to
mid-November. The highest number of trapped moths occurred
in September or August to September (Fig. 3). The ight period
of the minor peak was only observed during May (2005) or June
(2002, 2004, 2010 and 2011). Field dissection of infested wood
showed that a large number of larvae of different ages remained
in a dormant stage over the 2010 winter, whereas, in the spring
of 2011, they started feeding and boring into the tree. A cohort
of larger ones (10– 28% of total larvae) become full-grown in
late spring and could change to pupal stage and these may create
the minor ight. Most of the ZP larvae were much smaller,
continuing to feed throughout the season and become fully
grown only in the late summer, creating the larger peak.
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
14 E. Hegazi et al.
0
10
20
30
40
50
60
(A) (B)
(C) (D)
(E)
70
80
Moths/Trap/Month
2002
"on"
2003
"off"
0
10
20
30
40
50
60
70
80 2004
"on"
2005
"off"
0
10
20
30
40
50
60
70
80
Moths/Trap/Month
2006
"on"
2007
"off"
0
50
100
150
200
250
300
350
2008
"on"
2009
"off"
0
10
20
30
40
50
60
70
80
Moths/Trap/Month
Month
2010"
on"
2011
"off"
2010
"on"
Figure 3 (A –E) Monthly number of Zeuzera pyrina captured/trap in pheromone-light traps during the 2002– 2011 olive seasons. Vertical bars represent
the mean ±SD.
The yearly total season-long capture of leopard moths is shown
in Fig. 4(A). Generally, higher numbers of ZP moths were
trapped in ‘off’-years versus smaller ones in ‘on’-years. A 2-year
cycle can be seen directly in raw trap counts for 2002– 2011
(Fig. 4A). This is supported by time series analysis, as indi-
cated by the ACF plot in Fig. 4(B) showing yearly alternating
peaks. All seven of these were signicant by a Ljung– Box test
(P<0.05). However, PACF, which removes effect of correlation
to intermediate lag years, contains only one peak crossing the
condence interval of no effect, the rst lag peak (Fig. 4C). This
rst lag (t=t1) corresponds to a 2-year cycle (a previous year
is the most different, or in other words; years that are 2 years
apart are the most similar). From the original 10-series data,
no longer cycles, corresponding to higher lags, were discernible
(Fig. 4B,C).
When we included an estimate of trapping level for the
rst ‘outbreak’ in year 2001, an 11-year series with two large
‘outbreak’ peaks is clearly seen (Fig. 4D). The ACF plot for this
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
Population cycles of Z. pyrina 15
Year
20112010200920082007200620052004200320022001
Lag Number
87654321
Year
2011201020092008200720062005200420032002
Trap catch ln(y)
6.5
6.0
5.5
5.0
4.5
(A)
ACF
1.0
0.5
0.0
−0.5
−1.0
(B)
Lag Number
7654321
Partial ACF
1.0
0.5
0.0
−0.5
−1.0
(C)
(D)
(E)
(F)
Figure 4 Full season counts of captured Zeuzera pyrina moths during the 2002 2011 olive seasons. (A) Yearly catches for 10years of trapping,
2002– 2011, transformed by ln(x). , ‘on’ years with high fruiting. (B) Autocorrelation function (ACF) plot among years for the 10-year series at different
lags (past years). The series was differentiated by 1year to achieve stationarity (constant mean and variance over time). (C) Partial ACF plot (which
removes the effects of intervening years) for the 10-year series. (D) Yearly catches with an added, conservative estimate of catch for 2001 based on the
outbreak level observed that year, giving a 11-year series [transformed by ln(x)]. (E) ACF for the 11-year series, differentiated by 1. (F) Partial ACF for the
11-year series. In (A) and (B), the horizontal line is the mean of the series. In (B), (C), (E) and (F), solid lines give the 95% confidence limits for coefficients.
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
16 E. Hegazi et al.
new 11-year series again shows many strong values, passing the
95% condence lines at a lag of 1 and at a lag of 7 and 8 (Fig. 4E),
indicating that there might be both a 2-year cycle (peak years
are 2 years apart) and a possible 8- or 9-year cycle (peaks are
8 or 9 years apart) (Fig. 4E). However, the partial ACF strongly
supports only a signature of cycles at lag 1 (corresponding to a
2-year cycle), just as the original data set of only 10 years does
(Fig. 4F).
Female catches and natural enemies. Female catches were very
small. However, during the whole trapping season, of all trapped
leopard moths (218 and 505 moths/trap) in ‘off’-years of 2007
and 2009, only 10% and 13% were female, respectively. In
‘on’-years of 2008 and 2010, females represented 4.1% and
2.9%, respectively. Almost all females caught in the trap were
already mated and gravid, bearing approximately 500– 2000
eggs at various developmental stages. Very few leopard moths
were females during April to June of the trapping season.
From August until late October, the trapped females laid their
eggs on the sticky sheet of the trap (400– 950 eggs/female).
On 3 September 2007, 245 mid- to large-sized leopard moth
larvae were dissected from heavily-infested trees. We deter-
mined that 1.2% of larvae were parasitized by an ecto-parasitoid
wasp (Hymenoptera: Eulophidae: Hyssopus sp.), 1.6% were
infected by the entomopathogenic fungus Beauveria bassiana,
1.2% were infected by Metarhizium anisopliae and only one
larva was infected with entomopathogenic nematodes (Stein-
ernema sp.). On 15 September 2009, we dissected 155 ZP
larvae, although only 1.9% were infected by M. anisopliae,
whereas ants were seen to be busy collecting newly-hatched ZP
larvae.
Yield and economic losses
Figure 5 shows the fruit harvest/tree of apparently uninfested
and ZP infested trees in year 2006 (a ‘high fruiting year’) and
2007 (a ‘low fruiting year’). A very signicant difference as a
result of infestation was clear, with a much higher fruit yield
from uninfested trees compared with infested ones (P<0.0001).
However, not only the infestation factor (infested tree/apparently
uninfested), but also the year was a very signicant factor
in yield (P<0.0001), whereas there was no interaction at all
(P>0.10, factorial ) for infestation ×year. This means
that the relative importance of infestation by ZP was the same,
irrespective of the fruiting level of the host tree (Fig. 5). The
data in Table 1 summarize the economic loss in two plots
of a cropping system [Sennara (S) +To ff a hi (S ) ] cau s ed by
ZP under a natural infestation (n390 trees/variety/plot). The
two varieties appeared to have very similar yields within each
category of infestation and year (Table 1). Crop losses in weight
[LWin Eqn 1] were a function of the nal infestation and the
olive yield of the year. In 2006, the nal infestation near harvest
time varied between 30% and 61% for different varieties and
plots. The average annual crop losses (LW) were calculated as
between 2 and 5 t/ha, respectively, implying economic losses
[LEin Eqn 2] of some 1500 and 3200 $/ha. The average losses
of fruits on broken branches reached up to 8 and 6 kg/infested
tree for Sennara and Toffahi trees, respectively (Table 1). In
Year
2007 Low fruiting2006 High fruiting
95% CI Yield/tree (kg)
70
60
50
40
30
20
10
0
Infested tree
Apparently unifested
Infestation
Figure 5 The fruit harvest in two badly infested plots by Zeuzera pyrina,
in a 2006 season ‘on’ year and 2007 season ‘off’ year (mean ±SEM).
Infestation and year are both very highly significant factors by analysis of
variance at P>0.0001 (F1,12,both>50) (***) but not the interaction of
infestation ×year (F1,12 =2.9, P>0.10) (not significant; NS).
the low fruiting year of 2007, the infestation near harvest time
was 34– 41%. The average annual crop loss corresponded to
economic losses of some 1400–1700 $/ha (Table 1).
Spatial variation of infestation and yield with variety
intercropping
We observed the response of ve pairs of different olive vari-
eties with two different cropping systems, namely adjacent plots
with a pair of either susceptible or resistant varieties (Table 2).
Losses of yield (t/ha) for the susceptible varieties were sim-
ilar to those in Table 1, although much less in the resistant
varieties (Table 2). The three rst rows of Table 2, all with
resistant varieties in the target plots (R +R), show the clear-
est pattern. When the olive trees neighbouring the rst two of
these plots were resistant olive cultivars (only RR-type), infes-
tation and losses were at zero levels. By contrast, for the plot
with Picual (R) +Manzanello (R) as the third row, with the
susceptible olive cultivars of Toffahi and Sennara as neigh-
bouring plots (SS-type plots), infestation was 8– 10% in the
target plot (R +R). When two partly resistant cultivar mixes
(S +R) were surrounded by SS-type plots, infestation appeared
to be higher, 9– 19%, and, with all cultivars susceptible (S +S
with SS-type neighbour plots), achieved 25– 40% (Table 2, last
rows).
In target plots that had at least one resistant cultivar (R+R
or R +S; n=10), the inuence on infestation rate by the two
types of neighbouring plots [RR- or SS-types, mean ±SE;
0.0 ±0.0% (n=4) and 12.5 ±1.9% (n=6), respectively] was
quite signicant (Mann–Whitney U=24, P=0.010).
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
Population cycles of Z. pyrina 17
Discussion
We have clearly shown temporal variation in a yearly cycle
and a 2-year cycle of population dynamics. In addition, the
corresponding economic damage was quantied in detail for
different varieties. We also observed a spatial variation in
damage related to intercropping of resistant/susceptible varieties,
indicating a possible associational resistance.
Subsequent to early 1995, nine olive cultivars have been
planted in monoculture mixing olive varieties in desert area
near Cairo. In this area, an outbreak of the leopard moth ZP
was observed in 2001. One approach for understanding the
ZP population cycle comprises performing experiments on
long-term insect density during the initiation phase of a natural
outbreak (Myers, 1988; Krebs, 1991). Accordingly, we per-
formed long-term monitoring 1 year after the outbreak of the
leopard moth ZP. When studying normal annual cycling of this
insect in 2002–2011, we observed a new outbreak in 2009. The
strict isolation of this area, not in proximity to apple plantations
or any other known host plants of ZP and surrounded by sand
desert habitat, makes it ideal for studying a local population
without biotic inuence from landscape scale.
Temporal variation
Annual. The trapping study indicated that the ZP has an annual
biological cycle in olive trees in Egypt. Captures show the
occurrence of an early-season ight that continued throughout
the growing season and into the autumn and the beginning of
harvest. The largest ight of the year began near the end of the
season. The observation of a large number of larvae of different
sizes in a dormant stage over the winter of 2010 indicates a cohort
of larger individuals becoming full-grown in late spring resulting
a minor peak, whereas the smaller individuals become full grown
in late summer and create the major ight peak. In both cases,
this constitutes a single yearly cycle of reproduction. Thus, the
number of ight peaks appears to depend on the population age
structure of ZP larva, which is likely dependent on multi-year
temperature patterns.
The 2-year cycle. Our data and ARIMA time series analysis
clearly show a 2-year cycle in total catches. When attempting to
explain such annual trends in trapping the leopard moth, records
can be associated with alternative bearing in some fruit trees.
Olive (Olea europea) has very high tendency for year-to-year
deviation in yield (Lavee et al., 1996; Seyyednejad et al., 2001;
Lavee, 2007). Studies on changes in carbohydrate components
of leaves from ‘on’ (bearing) and ‘off’ (nonbearing) years cycle
have shown that sugars are much higher at the beginning of an
on- than of an off-year yield (Lavee et al., 1996; Seyyednejad
et al., 2001; Lavee, 2007; Erel et al., 2013). Also, the degree
of alternate bearing is highly dependent on the environmental
conditions and might be very different in accordance with the
climate in each growing region (Morettini, 1950; Hartmann,
1951; Sadok et al., 2013; Turktas et al., 2013; Yanik et al.,
2013). The depletion of stored carbohydrates during the on-year
(high yield) (Bustan et al., 2011) and environmental conditions
may affect the availability and quality of living wood as food
material for ZP larvae (Hoch et al., 2013). Thus, it appears that
living wood during the off-year is of a high ‘nutritional quality’
that accelerates larval growth, leading to a decline in natural
larval mortality, an increase in female fecundity and, in turn,
an increase in the annual trapped ZP moths in the subsequent
off-year season.
Outbreaks. Initiation of insect outbreaks is poorly understood
and the factors involved in the initiation of insect outbreaks
remain enigmatic (Maron et al., 2001; Myers & Cory, 2013).
There is a general asuumption that insect outbreak risk is higher
in plant monocultures than in natural and more diverse habi-
tats, although empirical studies investigating this relationship are
scarce (Jactel & Brockerhoff, 2007; Dalin et al., 2009). Other
explanations have been reported, including changes in food-plant
quality (Schultz & Baldwin, 1982; Mattson & Haack, 1987;
Rossiter, 1992), favourable weather (Martinat, 1987) and reduc-
tions in predation, parasitism or disease (Myers, 1988; Walsh,
1990), although satisfactory tests are difcult to employ. The
interaction of ZP with the parasitoids–pathogens observed in
the present study area appears to be too low to cause population
cycles. However, the results provide strong evidence of periodic
behaviour in population densities. It appears that the bearing pat-
tern (food-plant quality) in the monoculture farm may generate
herbivore periodic oscillations.
There is no apparent reason why large numbers were recorded
in most traps in 2009. Most studies of the population dynamics
of forest-defoliating insects suggest outbreak cycles ranging
from 8 to 12 years (Liebhold & Kamata, 2000). The gradual
reduction of infestation of forest tree by lepidopteran insects
is the manifestation of a 9-year cycle that includes 3 years of
population increase, 3 years of population at high levels and
3 years of population decline (Myers, 1988). It is reasonable to
speculate that outbreak cycles of ZP are within 8– 9years.
Spatial variation
Entomological studies on interplanted perennial crop plants are
scarce but indicate an effect of lower herbivore damage at a
higher tree diversity and the effects of specic semiochemicals
known as nonhost volatiles (Jactel & Brockerhoff, 2007; Jactel
et al., 2011). The present data are interesting in terms of rep-
resenting the rst estimate of losses in olive yield caused by
ZP. The observed trend suggests that mixing olive cultivars can
assist in pest control and provide yield advantages. Neighbour-
ing olive varieties can also inuence the rate of ZP colonization.
The results suggest that focal plants may gain protection from
herbivores because of their proximity to neighbouring plants and
thereby be defended by neighboring plants’ anti-herbivore phys-
ical or chemical traits (Baraza et al., 2006; González-Teuber &
Gianoli, 2008), forming a case of associational resistance (Bar-
bosa et al., 2009).
The present study is not intended to provide a generalized
denition for the attack threshold at which action should be
taken against ZP but rather indicates that the intercropping of
insect-resistant crop varieties among the susceptible varieties in
olive orchards is economically, ecologically and environmentally
advantageous. Ecological and environmental benets arise from
increases in species diversity in the agroeco-system, in part
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
18 E. Hegazi et al.
because of reduced use of insecticide (Teetes, 1994). Many olive
variety combinations are possible and each can have different
effects on benecial/harmful insect populations. For example,
the choice of tall resistant and short companion olives can
magnify these effects.
In all trapping seasons, larger numbers of ZP males were
caught compared with females in combined pheromone-black
light traps. We speculate that, because the females are
heavy-bodied, they might be extremely poor iers. How-
ever, the specic reason for the relatively higher female catch in
an ‘off’-year compared with that in an ‘on’-year is not known
and may need further investigation. These seasonal ights
can be readily identied with pheromone-black light traps in
naturally-infested susceptible olive cultivars, as indicated in the
present study.
Conclusions
The present data are interesting, providing the rst detailed
estimate of heavy economic losses in olive yield caused by ZP.
Control with conventional insecticides in this pest is almost
impossible because it is cryptic for most of the life cycle and
the use of systemic insecticides is more or less impossible in a
slowly maturing food crop. Integrated management, however,
allows both augmentation of benecial and chemical ecology
based management options such as mass-trapping (Hegazi et al.,
2009), mating-disruption (Hegazi et al., 2010) and an increase
of semiochemical diversity by intercropping (Zhang & Schlyter,
2003). As shown in the present study, the most directly appli-
cable method for this invasive pest comprises the monitoring of
distribution and population levels by pheromone traps. A more
detailed and replicated study of the spatial variation of damage
in relation to the composition of olive tree varieties and the quan-
tication of volatiles released from foliage is now under way.
Acknowledgements
We appreciate the constructive criticism of the referees. A critical
reading of an earlier draft by Dr S. Hagenbucher improved
clarity. We gratefully acknowledge grower-collaborator Mr M.
Sheta for providing several research plots in his orchards, as well
as more than 25 co-workers who provided invaluable help in
the eld. EH thanks the Alexander von Humboldt foundation
for a research donation used in the present study. This study
was carried out with the nancial support of SIDA/VR MENA
Swedish Research Links funds to FS and EH. FS was supported
by the Linnaeus programme ‘Insect Chemical Ecology, Ethology
and Evolution’ (ICE3)
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Accepted 10 May 2014
First published online 29 July 2014
© 2014 The Royal Entomological Society, Agricultural and Forest Entomology,17,919
... One alternative to monitoring is to use pheromone traps and surveys of their damage. Pheromone traps have been used in some cases, such as Z. pyirina in Apulia (Southern Italy) (Guario et al. 2002), control Z. pyrina with differences in size and color trap in Iran (Ardeh et al. 2014), its use for Z. pyrina in a walnut orchard (Rohani and Samih 2012), intial monitoring in E. pellita (Suheri et al. 2020), and control Z. pyrina on olive (Olea europea L.) orchard (Hegazi et al. 2015). Damage monitoring can be done by surveying several sampling sites to determine actual conditions in the field. ...
... population dynamics observed in E. pellita plantations showed a peak flight trend in October, followed by a reasonably high population in late May to early June as a continuation of Suheri et al. (2020). Hegazi et al. (2015) found two peak flight times (late April to October). At the same time, Almanoufi et al. (2012) claim that peak flights are found from May to July. ...
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Suheri M, Haneda NF, Anwar R, Jung Y, Sukeno S, Park J. 2022. Population dynamics of Zeuzera spp. (Lepidoptera: Cossidae) on Eucalyptus pellita plantation in Central Kalimantan, Indonesia. Biodiversitas 23: 5782-5789. The red coffee borer, Zeuzera spp. (Lepidoptera: Cossidae) damage to Eucalyptus pellita forests was one of the problems in the forestry sector. The population dynamic of these insects is monitored and surveyed on E. pellita at PT Korintiga Hutani. The present study aimed to analyze the contributing factors of Zeuzera spp. damage to E. pellita plantation and observe the population dynamics of Zeuzera spp. using pheromone traps. The survey results showed that the accumulated damage in planting block 5 was more serious (29%) than in planting block 6 (9%). The impact of the multi-regression analysis indicates that the main factors affecting the damage are the location and age of the plantation. At the same time, the E. pellita clonal difference is minor compared to those two factors. The damage is more severe and occurs at an older age of plantations. The population dynamics of Zeuzera spp. observed in E. pellita plantation showed a peak flight trend in October, followed by a reasonably high population presence from late May to early June. This information could be a primary consideration for these insect pest need to control the significant damage to E. pellita trees and determine the management of Zeuzera spp. based on the timing of larvae infestation in the upcoming after-peak flight.
... Ardeh et al. [42] found that doubling the size of a trapezoidal trap (and hence doubling the adhesive area), along with a greater entrance area, doubled the catch of moths compared with the standard delta traps for Zeuzera pyrina (L.) in walnut orchards in Iran. Once adequate trap-lure combinations were recognized, their use allowed the dynamics of adult flight of A. centerensis [39] and Z. pyrina [43,44] to be determined. ...
... However, we found that replacement of the lures loaded with 300 µg pheromone every eight weeks (56 days) allowed us to monitor the flight of males of C. valdiviana under field conditions during the whole season. This is consistent with the monitoring and mass trapping protocols reported for Z. pyrina in olive orchards, which suggest replacing pheromone lures every 40 days, although a much higher pheromone dose of 10 mg applied in polyethylene bags was used in these studies [43,44]. The higher dose might have been necessary for the type of dispenser used, because, presumably, the diffusion rate through the walls of the polyethylene bags is lower compared with the release rate of the pheromone from rubber septa. ...
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Chilecomadia valdiviana (Philippi) (Lepidoptera: Cossidae) is a native xylophagous pest in apple orchards in Chile. A series of experiments evaluated the efficacy of trap type, sex pheromone (Z7,Z10-16:Ald) dose, and trap location in the apple tree canopy on trap catch of male adults. Bucket traps (6 L), with and without roof and cross vane spacers, together with bucket traps (20 L) without roof and spacers, showed higher catches among the four types of traps evaluated. In a second experiment, the UNI-trap and Delta trap showed higher catches than Multipher, wing, and bucket traps (6 L). Male catches were not affected by height when tested at 0, 1.5, and 3 m in the canopy. A 300 µg dose of Z7,Z10-16:Ald showed higher catch than the control treatment. This dose allowed monitoring of male flight of C. valdiviana for at least five weeks in apple orchards in Chile. Based on relative trap costs, we propose the use of 6 L bucket traps for male mass trapping, while Delta traps can be used for monitoring of male flight. We found that male flight of C. valdiviana occurred mainly from mid-August to late November, reaching its maximum in mid-September.
... Increasing global warming and inappropriate distribution of rainfall due to climate change in the world have led to the leopard moth population outbreak in Iran and Middle East. The crop loss caused by this pest had significant economic impacts (Hegazi et al., 2015). The first step in the management of this pest is adhering to basic gardening principles and prevention methods. ...
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Background Leopard moth, Zeuzera pyrina L., is a key pest of walnut trees in arid and dry areas. It severely damages walnut tree gardens with limitations on irrigation water in the growing season. This study was conducted to compare the efficacy of trunk injections of three systemic insecticides: imidacloprid, oxydemeton-methyl, thiamethoxam and a complete fertilizer, Nutreeno® against the leopard moth. Trunk injection was done by drilling. The walnut annual shoots of 60 cm in length were sampled from four directions of the treated and control trees in 4 months after treatments. Results The results showed that all treatments including the insecticides and the complete fertilizer at higher concentrations had acceptable efficacy on the leopard moth, and thiamethoxam was the best treatment. Conclusions Trunk injections by neonicotinoid insecticides and Nutreeno can be a safer control method against leopard moth larvae in old walnut trees around residential areas.
... Similarly, Xyleutes ceramicus (teak beehole borer) emerges in March and flies for 2-3 months in Thailand (Chaiglom 1966). Some species, such as Zeuzera pyrina (the leopard moth) in Egypt have emergence periods of up to six months (Hegazi et al. 2015). An accurate understanding of the emergence period is important for a mass trapping programme to be effective, and also to minimise costs of its implementation. ...
Article
Coryphodema tristis (Lepidoptera: Cossidae) is a native wood-boring moth with a broad host range on both native and non-native vegetation and is an important pest of commercial Eucalyptus nitens plantations in South Africa. Management of C. tristis is challenging since the larvae spend the majority of their lifecycle tunnelling within the wood of host trees. Following the development of a synthetic sex pheromone for C. tristis, pheromone-based mass trapping of male moths was investigated as a tool to control the pest. More than 5 000 pheromone-baited yellow bucket funnel traps with extensions were deployed in E. nitens stands in 2016 and 2017. Evaluation of the efficacy of the mass trapping programmes was done in 2017 and 2018 through the destructive felling of infested trees and comparison of the ratio of new to old C. tristis colonies in trapped and non-trapped compartments. The results show a significant decrease in the ratio of new to old colonies in trapped compartments compared to non-trapped compartments. This study shows that the large-scale trapping of C. tristis using a synthetic sex pheromone is a viable management strategy to control C. tristis.
... In Egypt, damage caused by Z. Pyrina led to uprooting of olive groves by growers. The damage caused by larval tunnels in structurally critical wood can be extremely serious to a tree already bearing a fruit load; it causes ordinary branches to break under a medium load, whereas it may cause complete death of young trees with a heavy load as a result of damage to the major branches and trunk (Hegazi et al., 2015). ...
... Apple trees, in Egypt and in most world countries are attacked by various insect pests. Aphids, Codling moth, Leopard Moth, Clearwing Moth, dogwood moth, scale insects, leafminers, leafrollers, jewel beetles and bark beetles are the main insect pests attacking fruit trees, including apple orchards (Blommers 1994, Abdel-Azim 1997, Pfammatter & Vuignier, 1998, Anonymous 1999, Brown et al. 2008, Karaca et al. 2010, Simon et al. 2010, Hegazi et al. 2010, Hegazi et al. 2014, Batt & Abd El-Raheem 2017. ...
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The first part of the work aimed to study the survey of apple trees borers that attack apple orchards in two different geographical regions, at Abo-Mashour and Al-Khatatba locations (Menoufia governorate). Five species were recorded in the study showed, these borers were Synantheden myopaeformis Borkh., Zeuzera pyrina L., Hypothenemus eruditus Westwood., Scolytus amygdali Guer. and Chlorophorus varius Mull (non recorded at Al-Khatatba). Highest percentages of infestation (26.08 & 21.33 %) were recorded for Sy. myopaeformis followed by Z. pyrina (17.83 &13.01%) at Abo-Mashour and Al-Khatatba, respectively. An annual increase of infested trees with these borers, especially Sy. myopaeformis (10.59 & 9.59) and Z. pyrina (9.22 & 6.62) give serious indicators to quick devastation and the death of infested trees. The weather factors detected a significant correlation with infestation by different borers except Ch. varius. Also significant differences for both Z. pyrina and S. amygdale were detected in the two regions under study, while the infestation showed insignificant differences of both Sy. myopaeformis and H. eruditus The second part of the study aimed to investigate the role of phytochemical components within apple trees and their relation to the infestation with apple clearwing moth Sy myopaeformis. The analysis by GC-MS chromatograph showed differences in both Chemical composition and the percentages of compounds in the tested wood samples from apple trees under study. In the uninfested young trees (resistant trees), the levels of 9-Octadecenoic acid (Oleic acid), 9-Hexadecanoic acid and Ethyl iso-allocholate were found at higher rates than the uninfested old trees, as they were 31.42%, 14.83% and 5.37% respectively. The infested old trees showed high levels of these chemical compounds compared to uninfested ones as the percentages of 9-Octadecenoic acid (Oleic acid), 9-Hexadecanoic acid and Ethyl iso-allocholate increased by 5.8 fold, 3.1 fold and 3.1 fold, respectively, while the percentages in uninfested old trees were 7.42%, 5.39% and 3.34% respectively.
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FOREWORD May 2022, is a logical continuation of the I International Biology Congress, which took place in 2012 at the Kyrgyz-Turkish Manas University in Kyrgyzstan. The II International Biology Congress, as well as the I, was attended by many representatives of the scientific research world from different countries. The II International Biology Congress "Biocong.manas2022" provided an excellent opportunity for all participants, who represented different levels of education and science - from undergraduate students to professors and doctors of science - to publish the latest results of their biological research. This Full Paper Proceedings Book presents the articles of the participants following the results of the congress. The Organizing Committee expresses gratitude to our esteemed authors for the fruitful and exciting work and looks forward to furthering cooperation. With best wishes, Chairman of the Congress, Prof. Dr. Kurmanbekova Gulbubu Toktosunovna.
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Climate change is a crucial element propelling shifts in pest dispersals. Accurate evaluation of pest potential distributions for determining their establishment risks can lead to development of more efficacious pest management strategies. The leopard moth, Zeuzera pyrina (L.) (Lepidoptera: Cossidae), is a devastating pest with increasing significance particularly due to increasing frequency and severity of drought episodes in the context of global warming. In light of invasiveness and economic importance of this pest, it would be imperative to study the impact of climate changes on its worldwide distribution. In the current study, Maximum Entropy models were utilized to predict appropriate habitats for Z. pyrina under current and future climate scenarios averaged from four global climate models under two representative emission pathways in 2050 and 2070. Totally, 13703 presence occurrence records were compiled. The results indicated that at the present time, out of the total world’s land, 16.91% is climatically appropriate for the species including nearly 74% of Europe, greater than 19% of America, and more than 37% of Asia and Oceania. Under future climate conditions, the risk area of Z. pyrina in the northern and southern hemispheres were projected to expand northward and downward, respectively. The impacts of the global climatic changes on potential geographical distribution of Z. pyrina should be considered prior implementing any management program in the future. Moreover, our findings can be enlightening for biosecurity organizations in decision-making and serve as an early alerting to safeguard unaffected regions against the leopard moth invasion.
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zet Gövde ve dallarda beslenen Sarı ağaçkurdu, Zeuzera pyrina L. (Lepidoptera:Cossidae), birçok kültür bitkisinde oldukça zararlı olmakla birlikte, zeytin bahçelerinde de büyük ekonomik kayıplara neden olmaktadır. Bu çalışma, Z. pyrina'nın yayılışı ve bulaşıklık oranlarını belirlemek amacıyla 2014 yılı mayıs ve ekim ayları arasında Hatay iline bağlı Antakya ve diğer ilçelerindeki (Erzin, Dörtyol, İskenderun, Kırıkhan, Hassa, Reyhanlı, Altınözü, Yayladağı ve Samandağ) zeytin bahçelerinde, gözle kontrol metodu kullanılarak yürütülmüştür. Yapılan arazi çalışmaları sonucunda tüm ilçelerdeki zeytinliklerin zararlı ile bulaşık olduğu ve Z. pyrina'nın her ilçede yer yer önemli zarara yol açtığı saptanmıştır. Zararlının larva dönemi çalışmanın yapıldığı tüm lokasyonlarda mayıs-eylül ayları arasında görülmüştür. Çalışma sonucunda ilçelerin bulaşıklık oranı Dörtyol, Samandağ, İskenderun, Kırıkhan, Erzin, Reyhanlı, Hassa, Yayladağı, Antakya ve Altınözü ilçelerinde sırasıyla %58, %58, %52, %55, %49, %42, %41, %34, %33 and %28 olarak tespit edilmiştir. Abstract As a xyllophagous pest, Zeuzera pyrina L. (Lepidoptera:Cossidae) is harmful on many plant species and it also causes significant economic loses on olive orchards. This study was carried out to determine the infestation ratio and distribution of Z. pyrina in olive orchards of Hatay province (Erzin, Dörtyol, İskenderun, Kırıkhan, Hassa, Reyhanlı, Antakya, Altınözü, Yayladağı and Samandağ districts) between May and October in 2014 by using visual inspection method. As a result of the study, it was detected that olive trees were infested by the pest in all districts and cause locally important harm in each district. Larvea of the pest detected in all location where the study was done between May and September. Infestation rate of the pest was 58%, 58%, 52%, 55%, 49%, 42%, 41%, 34%, 33% and 28% in Dörtyol, Samandağ, İskenderun, Kırıkhan, Erzin, Reyhanlı, Hassa, Yayladağı, Antakya and Altınözü districts, respectively.
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The present study attempts to identify the biological characteristics of invasive (high-impact in the secondary area) bark beetles and borers species, contributing to their success in an invaded area. We selected 42 species based on the CABI website data on invasive species and information on the most studied regional faunas. Four groups of species with different invasion strategies were identified based on the cluster and factor analysis. The first one (inbred strategy) is characterized by flightless males, xylomycetophagy, low fecundity (~50 eggs), inbreeding, polyvoltinism, and polyphagy. Species with an aggressive strategy are poly- or monovoltine, feeds on a limited number of hosts, larval feeding on the inner bark, are often associated with phytopathogens, and produce aggregation pheromones. Representatives of the polyphagous strategy have a wide range of hosts, high fecundity (~150 eggs), larval feeding on wood, and their life cycle is at least a year long. For the intermediate strategy, the typical life cycle is from a year or less, medium fecundity, feed on inner bark tissues, mono- or oligophagy. Comparison with low-impact alien species showed that the most significant traits from the viewpoint of the potential danger of native plant species are high fecundity, polyvoltinism, presence of symbiotic plant pathogens, long-range or aggregation pheromones.
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Seasonal monitoring of the flight of the leopard moth borer, Zeuzera pyrina L. was conducted by pheromone traps in the experimental apple orchards of the Fruit Growing Institute and of the Agricultural University in Plovdiv (Central South Bulgaria) in the years 2002-2006. Two types of pheromone traps were used: Pherocon traps (Trécé, USA) with sticky changeable bottom and Mastrap (Isagro, Italy) dry funnel traps. The dispensers were products of Isagro, Italy. The traps were installed every year at the end of May and removed at the end of September. As a whole the flight of the leopard moth begins in the middle of June although in some years the first catches were recorded in the first decade of June. The mass flight was recorded mainly in July in all years of the study. The last catches were recorded at the end of August-beginning of September. The pheromone dispensers for Zeuzera pyrina L. have shown a good selectivity. No other species were caught in the traps. However, the catches were relatively low, considering that the population level of the pest, as estimated by injuries, was found to be quite high. No significant differences between the catches in sticky and dry traps was found in the orchards of the Fruit Growing Institute for all years of the investigations, but the catches on the dry traps were significantly higher than the catches on sticky traps in one of the orchards of the Agricultural University in both 2005 and 2006. The trend of seasonal flight in all orchards, estimated by the same kind of traps, sticky or dry, was very similar every year. The results of this investigation, which was carried out in Bulgaria for the first time, will be used for facilitating the usage of pheromone traps for this pest for the purposes of prognosis.
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Commercially available sex pheromone lures and traps were evaluated for monitoring male fall armyworm (FAW), Spodoptera frugiperda, in maize fields in the coastal region of Chiapas, Mexico during 1998-1999. During the first year, Chemtica and Trece lures performed better than Scentry lures, and there was no difference between Scentry lures and unbaited controls. In regard to trap design, Scentry Heliothis traps were better than bucket traps. In 1999, the pattern of FAW captured was similar to that of 1998, although the number of males captured was lower. The interaction between both factors, traps and lures, was significant in 1999. Bucket traps had the lowest captures regardless of what lure was used. Scentry Heliothis traps with Chemtica lure captured more males than with other lures or the controls. Delta traps had the greatest captures with Chemtica lure, followed by Trece and Pherotech lures. Several non-target insects were captured in the FAW pheromone baited traps, The traps captured more non-target insects than FAW males in both years. Baited traps captured more non-target insects than unbaited traps.
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A quarter century ago, the question was posed of whether a general hypoth-esis could explain population cycles of forest Lepidoptera. Since then, con-siderable progress has been made in elucidating mechanisms associated with cyclic dynamics of forest Lepidoptera. Delayed density-related parasitism and reduced fecundity during population peaks are common influences on population dynamics, although why fecundity declines is not understood. The hypothesis that sunspots explain cycles is rejected. The influences of delayed-induced plant defenses on populations are inconsistent, but interac-tions between plant chemistry, pathogens, and immunity remain rich areas for future study. Population dynamics of forest Lepidoptera can be syn-chronous over large geographic scales, and repeatable waves of spread of outbreaks occur for some species. Climate warming could modify species dis-tributions and population cycles, but mechanisms have not been elucidated and changes in cyclic dynamics are not generally apparent. Integration of top-down and bottom-up influences on cyclic dynamics and quantification of dispersal are necessary for progress in understanding patterns of insect outbreaks.
Book
Following the demise of the MAFF's Perma­ some leaflets to fill outstanding gaps. The nent Leaflet Series in 1985, it was suggested content of three leaflets has been altered more that the final editions of the crop pest advisory extensively. Thus, Chafer grubs (Chapter 32) leaflets should be produced in a bound volume now incorporates material from Leaflet 449, for the benefit of future agricultural entomolo­ Japanese beetle, which has been omitted from gists and others interested in crop pests. This this collection as this pest has not become idea originated outside MAFF but was enthusi­ established in Europe. Nematodes on straw­ astically supported by entomologists in MAFF, berry (Chapter 81) has been enlarged by the the agricultural research institutes and the uni­ addition of further information on free-living versities. As editor of the leaflets from 1965 nematodes from the plant pathology leaflet on until 1985, I offered to undertake the task of Soil-borne virus diseases of fruit plants. The compilation and editing, and this offer was joint plant pathology/entomology leaflet on accepted. Raspberry cane blight and midge blight has To prevent the book from becoming quickly been included, but the information has been outdated, the sections on control measures mainly restricted to raspberry cane midge and have been redrafted by the Advisory Entomol­ the title changed accordingly.
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Carbohydrate content changes in olive (Olea europaea L.) were determined during fruit ripening in on- and off-years. Results showed that contents of alcohol soluble sugars in fruit decreased during fruit development. In the on-year a marked temporary increase was evident at the beginning of fruit colour changes, In leaves,during the on-year, the content of alcohol soluble sugars decreased, after a primary increase. However, during the off-year a somewhat different pattern was observed. Glucose, fructose and mannitol, the main sugars of the alcohol soluble fraction of fruit, are found in decreasing order. Changes in glucose and fructose content were inversely proportional for 135 or 150 days after fruit set Thereafter, concomitant to decrease of glucose and fructose mannitol content increased. In leaves, mannitol, glucose and fructose are the major components of alcohol soluble sugars, with a different pattern during on- and off-years; i.e. the content of mannitol in the off-year was lower than that of the on-year. Polysaccharides of fruit and leaf in the off-year were higher than that of the on-year.
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Evaluates the hypothesis that if a climatic anomaly that favours an increase in fecundity and/or survival persists over several consecutive generations, its effects on a forest insect population may be multiplicative, and after some years of continuous increase the "released' population will cause noticeable defoliation. Mechanisms by which weather might cause changes in forest insect abundance are outlined; indirect effects are more likely to be significant, eg by influencing the level of stress in the host plant, which in turn affects its nutritional quality, chemical defences or digestibility. Outbreaks of spruce budworm Choristoneura fumiferana, forest tent caterpillar Malacosoma disstria and southern pine beetle Dendroctonus frontalis are used as examples. The nature of temporal and spatial variation in climatic patterns also needs to be introduced into analysis and interpretation. On balance, there is probably a rather low upper limit on the amount of variability in pest population levels that can be explained by weather variables. -P.J.Jarvis
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Catches throughout summer showed the extent to which a blended light-trap (L1) and a black light-trap (L2) attracted nocturnal insects. Dominant orders among 23500 specimens were Diptera (68%), Lepidoptera (16%) and Hymenoptera (5%); distributed in the ratio L1: L2 = 1.12. Weather conditions did not influence this ratio. Lepidoptera, Trichoptera, Psychodidae and Hymenoptera were blended lamp-positive ( L1 : L2≥ 1.40), while Heteroptera, Homoptera, Culicidae and Mycetophilidae ( L1 : L2≤ 0.79) were near UV-positive. Other groups showed less specific responses. Within the Heteroptera and Lepidoptera some abundant species markedly influenced the L1: L2 ratio. /// Сборы в течение лета показали, в какой степени ловушки со смешанным светом ( L<sub>1</sub>) и затемненным светом ( L<sub>2</sub>) привлекают ночных насеконых. Среди 23500 видов доминировали представителн отрядов Diptera (68%), Lepidoptera (16%) у Hymenoptera (5%). Соотношение в скорости отлова между ловушками L<sub>1</sub>: L<sub>2</sub>=1,12. Погодные условия не влияют на это соотношение. Lepidoptera, Trichoptera, Psychodidae и Hymenoptera положнтельно реагируют на повушки со смешанным светом ( L<sub>1</sub>: L<sub>2</sub>=1,40), а Heteroptera, Homoptera, Culicidae и Mycetophilidae ( L<sub>1</sub>: L<sub>2</sub>=0,79) почти положительно - на УФ-свет. Реакции насекомых других групп менее специфичны. Среди Heteroptera и Lepidoptera некоторые многочисленные виды заметно влияют на соотношение L<sub>1</sub>: L<sub>2</sub>.
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Insect~resistant crop varieties can be an important component of an integrated pest management program. To achieve use in production agriculture, however, is more difficult than might be expected. The process of deployment after development of the insect·resistant eullivar by research entomologists and plant breeders involves Extension Service cooperation and industry commitment. Education of professionals and growers relative to the role inscct·l'esistant cultivars play in integrated pest management is key to successful deployment and continued use. Similarly, the need to adjust crop management recommendations for insect-resistant crop varieties requires changes in tradjtional information made available to growers_ For example, information on economic threshold levels, based on economic injury level research data, is required when making insecticide-use decisions to control insect pests on resistant and susceptible cultivars_ Insecticide use requirements for control of insect pests on resistant cultivars likewise often change. The information required and adjustments to crop management recommendations must be such that there is confidence in the use of insect-resistant cultivars. Examples of adjustments to management recommendations are presented using insect-resistant sorghums as a case history.
Article
Three compounds have been identified in the abdominal tip extracts from the female leopard moth,Zeuzera pyrina L. Gas-liquid chromatography and mass spectroscopy data showed that (E, Z)-2, 13-octadecadien-1-ol acetate was the main component and that (Z)-13-octadecen-1-ol acetate and octadecan-1-ol acetate were secondary components. The electroanten-nographic responses of maleZ. pyrina to nanogram amounts of all four 2, 13-octadecadien-1-ol acetate isomers indicated that theE, Z isomer had the maximum activity. A strong EAG response was also recorded for (Z)-7-do-decen-1-ol acetate, which was not detected in the female extracts.