This is not the document you are looking for? Use the search form below to find more!

Report home > Science

CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES

1.00 (1 votes)
Document Description
We investigated whether cassava plants that are infested by the cassava mealy- bug, Phenacoccus herreni (Pseudococcidae, Sternorrhyncha), emit attractants for the encyrtid parasitoids Aenasius vexans Kerrich, Apoanagyrus (Epidinocarsis) diversi- cornis Howard, and Acerophagus coccois Smith. Bioassays with a Y-tube olfactometer showed for all three species that female wasps were most responsive and selective when they were 1.5 to 2.5 days old. Females of these age groups were used to test their ability to distinguish between the odor of plants with and without mealybugs. The wasps were offered choices between infested cassava leaves vs. healthy ones, infested leaves vs. clean air, and healthy leaves vs. clean air. A. vexans and A. diversicornis were strongly attracted to infested leaves and preferred these over healthy ones. In contrast,A. coccois was significantly attracted to either healthy or infested leaves, and did not distinguish between the two.The results suggest that A. coccois, which has the broadest known host range of the three, may be responsive only to general plant odors, while A. vexans and A. diversicornis respond more specifically to odors associ- ated with mealybug infestation.
File Details
  • Added: September, 13th 2009
  • Reads: 721
  • Downloads: 38
  • File size: 311.26kb
  • Pages: 13
  • Tags: aenasius vexans, apoanagyrus, epidinocarsis, diversicornis, acerophagus coccois, cassava, manihot esculenta, host location, semiochemicals
  • content preview
Submitter
  • Username: shinta
  • Name: shinta
  • Documents: 4332
Embed Code:

Add New Comment




Related Documents

Quick Products For How To Get Rid Of Stretch Marks - Where To Go

by: holleatunce54567, 2 pages

highly prone to scarring * Possibility of re-acquiring of cold sores in patients having a history of herpes outbreaks - Laser Therapy - Laser therapy has

Get Rid Of Scars -- Simplest Way To Eliminate Stretchmark S

by: nalle1967455, 1 pages

function strong in the skin color to supply the entire body with all the vitamins had to repair alone , to

Quick Products For How To Get Rid Of Stretch Marks - Where To Go

by: holleatunce54567, 2 pages

Org natural skin care creams and heal your skin problems gradually without any side effects that other creams about the

Designed to make the everyday easier: Toshiba adds three new models to the Satellite laptop range

by: joline, 4 pages

Toshiba UK today announces the addition of three new models to its Satellite laptop series - the Satellite L670, Satellite L650 and Satellite C650. Designed to offer stylish and affordable computing, ...

How to use the diffusion model : Parameter recovery of three methods : EZ, fast-dm, and DMAT

by: shinta, 11 pages

Parameter recovery of three different implementations of the Ratcliff diffusion model was investigated: the EZ model (Wagenmakers, van der Maas, & Grasman, 2007), fast-dm (Voss & Voss, ...

Assessment of Some Mango Species by Fruit Characters and Fingerprint

by: shinta, 5 pages

Six local mango accessions; Zebda, Zaghloul, Gemela, Ganofia, El-Madam and El- Kobbaneia were collected from private farm in Sharkia Governorate. Physical and chemical characteristics of ...

Three simple ways to Grow Taller naturally

by: praveenben, 10 pages

http://www.growtallerforidiotsv.com Click the above url to get more information about Three simple ways to Grow Taller naturally. Grow taller 4 idiots can teach you on the proper exercise, nutrients, ...

Arrangement-to-Lookup for the businesses of is a Arrangement-to-Eradicate

by: cleovazquez513, 1 pages

How to Select a Value Helpful Agreement Retain the services of Business Finding the proper agreement hire organization is a challenging selection with such a large assortment to pick from. It is ...

Assessment of the effect of drying methods on the chemical composition and in vitro gas production of two woody species

by: shinta, 5 pages

The effect of the drying method on the forage quality of two browse species (Arbutus unedo and Robinia pseudoacacia) was investigated at three phenological stages. Hand-picked samples were ...

THE ROLE OF REACTIVE OXYGEN SPECIES AND CAPSAICIN- SENSITIVE SENSORY NERVES IN THE PATHOMECHANISMS OF GASTRIC ULCERS INDUCED BY STRESS

by: shinta, 15 pages

Gastric microcirculation plays an important role in the maintenance of the gastric mucosal barrier and mucosal integrity. Sensory nerves are involved in the regulation of mucosal blood ...

Content Preview

Bertschy et al.: Attraction of cassava mealybug parasitoids 383
CHEMICALLY-MEDIATED ATTRACTION OF THREE
PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA
LEAVES
CATHERINE BERTSCHY, TED C. J. TURLINGS,2 ANTHONY C. BELLOTTI1
AND SILVIA DORN3
Institute of Plant Sciences, Applied Entomology,
ETH (Swiss Federal Institute of Technology), CH-8092 Zurich, Switzerland
1Centro Internacional de Agricultura Tropical, CIAT, Cali, Colombia
2Current address: Institut de Zoologie, Université de Neuchâtel,
CH-2007 Neuchâtel, Switzerland
3To whom correspondences should be addressed
ABSTRACT
We investigated whether cassava plants that are infested by the cassava mealy-
bug, Phenacoccus herreni (Pseudococcidae, Sternorrhyncha), emit attractants for the
encyrtid parasitoids Aenasius vexans Kerrich, Apoanagyrus (Epidinocarsis) diversi-
cornis
Howard, and Acerophagus coccois Smith. Bioassays with a Y-tube olfactometer
showed for all three species that female wasps were most responsive and selective
when they were 1.5 to 2.5 days old. Females of these age groups were used to test their
ability to distinguish between the odor of plants with and without mealybugs. The
wasps were offered choices between infested cassava leaves vs. healthy ones, infested
leaves vs. clean air, and healthy leaves vs. clean air. A. vexans and A. diversicornis
were strongly attracted to infested leaves and preferred these over healthy ones. In
contrast, A. coccois was signi?cantly attracted to either healthy or infested leaves, and
did not distinguish between the two. The results suggest that A. coccois, which has the
broadest known host range of the three, may be responsive only to general plant
odors, while A. vexans and A. diversicornis respond more speci?cally to odors associ-
ated with mealybug infestation.
Key Words: Aenasius vexans, Apoanagyrus (Epidinocarsis) diversicornis, Acerophagus
coccois
, cassava (Manihot esculenta), host location, semiochemicals
RESUMEN
Se investigó si las plantas de yuca que son infestadas por el piojo harinoso, Phena-
coccus herreni (STERNORRHYNCHA: Pseudococcidae), emiten sustancias atractivas
para los parasitoides Encyrtidae Aenasius vexans, Apoanagyrus (Epidinocarsis) diver-
sicornis
y Acerophagus coccois. Ensayos con un tubo olfactómetro en Y mostraron que
las tres especies tienden a responder y seleccionar más frecuentemente cuando tienen
de 1.5 a 2.5 días de edad. Las hembras de esta edad fueron usadas para determinar
su capacidad de distinguir entre el olor de plantas con y sin piojos. Se ofreciò a las
hembras olores de yuca infestadas o limpias, hojas infestadas o aire puro y hojas lim-
pias o aire puro. A. vexans y A. diversicornis fueron atraídas fuertemente por las hojas
infestadas y presentaron preferencia por estas hojas contra las hojas limpias. En con-
traste, A. coccois fue atraída de manera signi?cante por hojas limpias u hojas infesta-
das contra aire, y no pudo dintinguir entre ambos olores. Los resultados sugieren que
A. coccois, que tiene el más alto rango de huéspedes de los tres, puede responder sólo
a los olores generales de las plantas, mientras A. vexans y A. diversicornis responden
más especi?camente a los olores asociados con la presencia de los piojos harinosos.


384
Florida Entomologist 80(3)
September, 1997
Cassava mealybugs are among the most damaging pests of cassava in South
America and Africa (Vargas & Bellotti, 1984). The two most important species are
Phenacoccus herreni Cox & Williams and P. manihoti Matile-Ferrero (Sternorrhyn-
cha: Pseudococcidae), which both originate from South America (Cox & Williams,
1981; Bellotti et al., 1984). P. herreni appeared as a problem rather suddenly in North-
east Brazil in the mid 1970s and was then reported from Colombia, Venezuela and
Guyana (CIAT, 1984; 1987; 1988; 1990); it can cause root yield losses up to 80% (Bel-
lotti et al., 1984; Bellotti, 1983). In Africa, the closely related P. manihoti became a se-
rious pest in most of the cassava growing regions after its accidental introduction in
the 1970s (Matile-Ferrero, 1977; Herren & Neuenschwander, 1991). For both pest spe-
cies biological control programs have been developed. The encyrtid parasitoid
Apoanagyrus (Epidinocarsis) lopezi (De Santis) was successfully released in African
in the 1980s. It established and now maintains the mealybug population at an accept-
able low-density in most regions (Herren & Neuenschwander, 1991; CIAT, 1992). For
the 5% of the African cassava ?elds where the parasitoid has not been effective in con-
trolling the mealybug (Neuenschwander et al., 1991), alternative control agents were
investigated such as two strains of the coccinellid predator Hyperaspis notata Mul-
sant (Stäubli Dreyer et al., 1997a; 1997b; 1997c).
Natural enemies of P. herreni have been systematically collected for the control of
the mealybug in South America, and laboratory colonies of three encyrtid parasitoids
were established at CIAT (Centro International de Agricultura Tropical), in Cali, Co-
lombia. These parasitoids are Aenasius vexans Kerrich, Apoanagyrus (Epidinocarsis)
diversicornis Howard (asexual strain) and Acerophagus coccois Smith (CIAT, 1982;
1983; 1990). Knowledge on the biology of these insects is limited. Published informa-
tion is mostly restricted to CIAT reports (1982-1992).
At the beginning of this century, studies showed that parasitic wasps use olfaction
to locate hosts and that they may ?rst be attracted to the food that their hosts feed on
(Picard & Rabaud, 1914; Thorpe & Jones, 1937; Thorpe & Caudle, 1938). More re-
cently, it was demonstrated that herbivore-damaged plants can play a key role in at-
tracting enemies of insect herbivores (Dicke et al., 1990; Turlings et al., 1990; 1995;
Vet & Dicke, 1992). For example, lima bean plants under spider mite attack release
speci?c volatiles that are attractive to predatory mites (Dicke et al., 1990) and similar
volatile compounds released by caterpillar-infested maize plants are used by parasi-
toids to locate caterpillars (Turlings et al., 1990).
Volatiles emitted by mealybug-infested plants are also suspected to attract natu-
ral enemies of the mealybug (Nadel & van Alphen, 1987). Changes in chemicals pro-
duced by the cassava plant due to P. manihoti infestation have been reported by
Calatayud et al. (1994). Such changes could result in the emission of volatiles and ex-
plain why A. lopezi and A. diversicornis (sexual strain) are attracted by P. manihoti-
infested cassava plants (Nadel & van Alphen, 1987; van Alphen et al., 1990). The feed-
ing behavior of P. herreni is very similar to that of P. manihoti (Castillo & Bellotti,
1990), and it can be expected that they evoke similar reactions in the cassava plant.
However, studies with the asexual strain of A. diversicornis of South America by Hof-
stee et al. (1993) showed no response by this parasitoid to the odor of P. herreni-in-
fested cassava plants (var. Odungbo). A better understanding of the interactions
between cassava plants, mealybugs, and parasitoids requires more behavioral as well
as chemical studies.
In this paper, we report on olfactometer studies with the three encyrtid parasitoids
reared at CIAT, A. vexans, A. diversicornis (asexual strain), and A. coccois. The studies
were conducted to determine whether these parasitoids are attracted to odors that
may emanate from cassava plants infested by P. herreni.


Bertschy et al.: Attraction of cassava mealybug parasitoids 385
MATERIALS AND METHODS
Plants
CMC40 cassava stakes (20 cm long) were planted every week in pots and kept in
a screened compartment, where they were subjected to natural weather conditions at
Palmira, Colombia, though protected from rain. The plants were used in experiments
when they carried 10-30 leaves (approximately 6 weeks after planting).
Insects
The cassava mealybug, P. herreni was reared at CIAT on potted cassava plants
(var. CMC40). Every week 30-40 cm high plants were infested with 15 mealybug
ovisacs, as described by van Driesche et al. (1987). The plants were separated in dif-
ferent cages based on the age of the mealybugs they carried.
The parasitoids, A. vexans, A. diversicornis and A. coccois were continuously
reared at CIAT on mealybug-infested cassava plants (var. Mcol 1505). The colonies of
A. vexans and A. coccois were initiated with insects collected in Venezuela in 1990 and
the colony of A. diversicornis with insects from Colombia (1984). The colonies were
maintained in a greenhouse at 35°C and under natural light conditions.
The Olfactometer
A Y-tube olfactometer similar to the one ?rst described by Sabelis & van de Baan
(1983) was used in our experiments (Fig. 1). Two arms of a glass Y-shaped tube were
connected to glass chambers (6.5 cm diam.) in which odor sources could be placed. Ac-
tivated charcoal ?ltered air at a rate of 400 ml/min was pushed into each glass cham-
ber. To avoid visual distractions and to diffuse the light, a wooden frame covered with
white cloth was placed around the Y-tube. A lamp (100 watt) was placed outside this
visual barrier opposite from the entrance where the insects were introduced. As these
parasitoids are attracted by light, the lamp helped to induce the insects to walk up-
wind in the direction of the odor sources. When a female reached the center of the Y-
tube, where the three arms met, she could choose one of the offered odors.
Odor Sources
Every week ovisac-infested cassava plants were transferred into a greenhouse,
where they were kept in nylon cages for three weeks before being used for the Y-tube
experiments. Control (healthy) plants were transferred weekly from the screened
compartment and enclosed in a nylon screen cage in the same greenhouse as the in-
fested plants. Care was taken that no mealybugs came in contact with healthy plants.
To serve as an odor source, two leaves of either infested or healthy plants were cut off
and the cut ends were wrapped in wet cotton wool. The leaves were carefully placed
in one of the odor chambers. The infested leaves that were selected carried honeydew
and sooty mold, as well as mealybugs and exuviae.
Experimental Procedure
On the day of each experiment, parasitoid females were removed from their cage
and kept in a glass jar (400 ml) with some honey. The jar was placed in the air-condi-
tioned chamber (28-30°C) where the experiments would take place. The insects were
left one or two hours in their new environment to become adjusted. Before each olfac-
tometer test, female parasitoids were allowed to parasitize a mealybug on a cassava
leaf. An infested cassava leaf was placed upside down in a petri dish and several fe-


386
Florida Entomologist 80(3)
September, 1997
Fig. 1. Diagram of the olfactometer set-up. Drawing by Urs Lengwiler.
males were introduced and observed until they had parasitized, or at least stung a
mealybug. The parasitoids were given this experience as it may increase their respon-
siveness to host-related odors (Turlings et al., 1993; Vet et al., 1995, Steinberg et al.,
1992). The parasitoids were then captured in a gelatin capsule and kept there for 10
to more than 60 minutes. Before each Y-tube test, the gelatin capsule was opened and
inserted at the base of the Y-tube. Females were introduced and were observed indi-


Bertschy et al.: Attraction of cassava mealybug parasitoids 387
vidually in the olfactometer and used only once. The odor sources were reversed each
time three wasps had been tested.
Evaluation of Choices
A stopwatch was started when the insect left the gelatin capsule. The female was
allowed 5 minutes to walk up the no-choice-area (Fig. 1) to reach the center of the ol-
factometer, which is the area where the three arms meet. If a female did not reach this
center within 5 minutes, she was counted as a “no-choice”. For the other females, the
observation was stopped 5 minutes after they had made it to the center, or after they
had reached the end of one of the arms. Each arm, was divided into four zones (Fig.
1), which measured 8, 6, 6, and 3 cm, respectively.
A female had to enter at least zone 2 (Fig. 1) to be considered to have made a
choice. A few females switched arms after reaching zone 2. In those cases, females
were considered to choose the arm which they entered the furthest. For statistical
analyses, a chi-square test was applied, using the total number of females that made
a choice for a particular odor (? = 0.05).
PROCEDURES AND RESULTS
The Effect of Wasp Age
It has been shown that the responsiveness to odors may change when parasitoids
get older (e.g. Thorpe & Caudle, 1938; Steinberg et al., 1992). To determine the opti-
mal age of our parasitoids for olfactometer bioassays, parasitoid females of different
ages were tested. Newly emerged wasps were isolated daily at about noon and trans-
ferred to Plexiglas® cages in which they were provided honey and water. The insects
remained in the cage until they had reached a certain age. Six different age classes
were tested, varying from 0.5 to 6.5 days after emergence. Each wasp was given an
oviposition experience, and then introduced into the olfactometer, in which they had
a choice between the odors of infested and healthy cassava leaves.
Responsiveness, i.e. proportion of females that made a choice, did not decrease
with increasing age of females. Overall it was high for A. diversicornis with an aver-
age of 73% and medium to low for both A. vexans and A. coccois with an average of re-
spectively 49 and 48% of the responding females.
Preference for an odor source changed in two of the three species (Fig. 1-3). In A.
vexans and A. diversicornis, the preference for the odor of infested leaves over odor of
healthy leaves was age dependent and signi?cant for young females only. Of the
younger (1.5-2.5d old) A. vexans females, 80% preferred infested cassava leaf odors (?2
= 7.2, P < 0.01). The youngest A. diversicornis (0.5-1.5d) showed the clearest prefer-
ence (82.6%) for the odor of infested leaves over the odor of healthy leaves (?2 = 9.78,
P < 0.005), but 17.4% of the females that made a choice switched between arms before
making a ?nal decision. The 1.5 to 2.5-day-old A. diversicornis switched arms much
less (3.8%), but exhibited a weaker preference for odors of infested leaves (69.2%, ?2 =
3.85, P < 0.05). The older wasps showed no signi?cant preference. All age classes of A.
coccois
did not differentiate between infested and healthy plant odors. Like A. diver-
sicornis
, A. coccois walked a lot in the olfactometer, often switching between arms
(26.3% of the choosing females).
The Role of Plant Odors
In a subsequent series of experiments we more speci?cally determined the relative
attractiveness of healthy and infested cassava leaves. Based on the results of the pre-


388
Florida Entomologist 80(3)
September, 1997
while the x-axis
hoice is given,
.
lass
lasses between the odors of mealybug-infested and
asps that made a particular c
the right of the bars is the proportion of females that made a
o

T
females of different age c
vexans
h bar the actual number w
A.
.
In eac
asps that the numbers represent.
.
Choices by
hoosing w
,
as well as the total number of females that were tested per age c
-tube olfactometer
Y
ves in a
va lea

Age dependency of response
.
2.
i
g
F
healthy cassa
indicates the percentages of c
c
hoice for one of the two odors


Bertschy et al.: Attraction of cassava mealybug parasitoids 389
while the x-axis
hoice is given,
.
lass
lasses between the odors of mealybug-infested and
asps that made a particular c
the right of the bars is the proportion of females that made a
o

T
females of different age c
sicornis
h bar the actual number w
diver
A.

.
In eac
asps that the numbers represent.
.
Choices by
hoosing w
,
as well as the total number of females that were tested per age c
-tube olfactometer
Y
ves in a
va lea

Age dependency of response
.
3.
i
g
F
healthy cassa
indicates the percentages of c
c
hoice for one of the two odors


390
Florida Entomologist 80(3)
September, 1997
vious experiments, only females that were 1.5 to 2.5 days old were used. On a given day
three different pairs of odor sources were tested, namely “Infested vs. Healthy”, ”In-
fested vs. Blank”, and “Healthy vs. Blank”. In the case of “Blank”, one arm introduced
clean air that had passed through an odor chamber with just a piece of wet cotton wool.
For each pair of odor sources, 4 to 6 insects per day were individually tested in the Y-
tube. Occasionally, another series of 6 insects per odor source was tested the same day.
A. vexans females were signi?cantly attracted to infested cassava leaves compared
to healthy ones or a blank (Fig. 5a). Healthy leaf odors were less attractive, since only
64.5% of the females responded in the “Healthy vs. Blank” test without showing a sig-
ni?cant preference for one of the two odor sources (?2 = 2.5, P > 0.05).
A. diversicornis females were signi?cantly attracted to infested and healthy cas-
sava leaves when offered against a blank. They also showed a signi?cant preference
for infested cassava plant odors over healthy ones (?2 = 6.08, P < 0.025).
Only 51.7 to 58.3% of A. coccois females made a choice, but these were signi?cantly
attracted by healthy and infested plant odors when offered against a blank (?2 = 7.53,
P < 0.01 and ?2 = 11.65, P < 0.001). In the “Infested vs. Healthy” test, the choosing fe-
males very often switched sides before going up one arm, and they showed no signi?-
cant preference for either odor source (?2 = 0.26, P > 0.05) (Fig. 5c).
DISCUSSION
The preference of female wasps to plant odors in the olfactometer was age depen-
dent for A. vexans and A. diversicornis. The younger age classes of both these species
signi?cantly preferred the odor of infested leaves, while older females showed no par-
ticular preference. The preferences exhibited by young A. vexans and A. diversicornis
may have been due to the experience that the wasps received with an infested leaf just
before their introduction into the olfactometer. During such an experience the females
may learn to respond to the odors that they encounter through a process of association
(Turlings et al., 1993; Vet et al., 1995), which may be age dependent. Some parasitoids
only learn as young adults (Kester & Barbosa, 1991), which could explain why older
wasps did not make a distinction in our tests. It is possible that if these older wasps
had been given an experience at a younger age, they would have shown a preference
as well. In the subsequent experiments only younger females were used.
For A. coccois, the lack of preference of females of any age class may be due to the
particular choice offered. This species obviously did not distinguish between infested
and healthy cassava leaves. An alternative choice, such as between plants and a blank
might have revealed a similar age dependency of the response as found for the two
other species.
All three species distinguished between plant material and clean air (blank). A.
vexans showed only a marginal attraction to healthy leaves, but was strongly at-
tracted to infested leaves. A. diversicornis was attracted to healthy leaves, but pre-
ferred the odor of infested leaves. A. coccois was also attracted to both healthy and
infested leaves, but did not distinguish between these two odor sources. These differ-
ences in response of the three encyrtid parasitoids suggest that they may employ dif-
ferent foraging strategies. A. vexans and A. diversicornis recognized odors that are
speci?cally associated with mealybug infestation. A. coccois, on the other hand, ap-
peared to respond only to general cassava plant odors. It remains unknown if A. vex-
ans
and A. diversicornis are attracted to odors emanating directly from the mealybugs
or if the infested plants emit the attractive odors.
In the petri dish, where females were experienced by giving them the opportunity
to walk over a cassava leaf and sting a mealybug, A. vexans walked slower, but showed
a more direct orientation towards mealybugs. This slower, but directed searching be-

Bertschy et al.: Attraction of cassava mealybug parasitoids 391
while the x-axis
hoice is given,
.
lass
lasses between the odors of mealybug-infested and
asps that made a particular c
the right of the bars is the proportion of females that made a
o

T
females of different age c
coccois
h bar the actual number w
A.
.
In eac
asps that the numbers represent.
.
Choices by
hoosing w
,
as well as the total number of females that were tested per age c
-tube olfactometer
Y
ves in a
va lea

Age dependency of response
.
4.
i
g
F
healthy cassa
indicates the percentages of c
c
hoice for one of the two odors

392
Florida Entomologist 80(3)
September, 1997
.
In
asps
ves
asps that
.

The w
,
as well as the
.
infested lea
hoosing w
ves vs
-tube olfactometer
Y
,
in a
,
and healthy lea
coccois
A.

ves
hoice for one of the two odors
and (C)
.
infested lea
sicornis
while the x-axis indicates the percentages of c
diver
lean air vs
A.
,
c
ves
,
(B)
hoice is given,
vexans
A.

.
healthy lea
.
(A)
.
hoice
lean air vs
c
asps that made a particular c
Next to the bars the proportion is given of the females that made a c
hoices between the odors of:
Responses of the three parasitoid species
.
5.
i
g
F
h bar the actual number w
were offered c
eac
the numbers represent.
total number of females that were tested per c

Download
CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES

 

 

Your download will begin in a moment.
If it doesn't, click here to try again.

Share CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES to:

Insert your wordpress URL:

example:

http://myblog.wordpress.com/
or
http://myblog.com/

Share CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES as:

From:

To:

Share CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES.

Enter two words as shown below. If you cannot read the words, click the refresh icon.

loading

Share CHEMICALLY-MEDIATED ATTRACTION OF THREE PARASITOID SPECIES TO MEALYBUG-INFESTED CASSAVA LEAVES as:

Copy html code above and paste to your web page.

loading