VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
DISTRIBUTION OF INSECTS ACCORDING TO THE PHENOLOGICAL
STAGES OF OKRA (Abelmoschus esculentus) AND PHYTOSANITARY
PRACTICES IN ANNA (BINGERVILLE, CÔTE D’IVOIRE)
Claudine Akoua Miezan N’guettia, Mauricette San-Whouly Ouali-N’goran, Sorho Fatogoman and Kone
Daouda
Laboratory of Zoology and Animal Biology, UFR of Biosciences, University Félix
Houphouët-Boigny, 22 BP 582 Abidjan 22, Côte d’Ivoire
Department of Biosciences, Laboratory of Plant Physiology, University Felix Houphouet-Boigny, Côte d’Ivoire
E-Mail: [email protected]
ABSTRACT
Insect distribution on okra cultivation was studied according to phenological stages. The study was conducted
from July to December 2015 in Anna, a village located at 4 km from Bingerville. The study aims at making an inventory of
the insects that colonize okra cultivation, the damage caused and the practices for controlling these pests. Insect collection
was carried out by hand pick-up, using colored traps or sweep nets. In total 9 orders of insects divided into 38 families
including 15 families of pests were counted. The flowering-fruiting stage was the most attacked. Damage was observed on
all organs of the plant. They were expressed by perforations and yellowing of leaves, falling flowers and immature fruits.
Podagricasp was the major pest of the crop with 54.57% of the population followed by Dysdercussp 25% and Nisotrasp
22.64%. Some useful insect species were identified. For the control of insect pests, producers use Ocimumgratissimum L.
(Lamiaceae) for its insect repellent properties. Two chemical pesticides approved for vegetable crops were reported (Koptimal, cypercal 50) but doses and frequencies were not respected, no protection measures were used.
Keywords: okra, insects, phenological stages, phytosanitary control practices, bingerville, côte d’Ivoire.
INTRODUCTION
In Côte d’Ivoire, market gardening has become a
source of employment and income for urban and periurban populations (Fondio et al., 2007). Among the
consumer vegetables, okra is ranked first before eggplant
and tomato (DSDI, 2005). Okra is grown for its young
fruits and leaves that can be eaten raw, cooked or fried
(N’Guessan, 1987). Fresh fruits are rich in calcium and
vitamin C and dry fruits rich in protein and lipid (Charrier,
1983). Unfortunately, in many tropical countries, okra
cultivation faces many constraints that affect the level of
production (Gnago et al., 2010). Among them, insects are
the most dreadful with direct effects on crops and indirect
effects by transmitting diseases (Makondy, 2012). The
consequences of such damage include a significant drop in
production and a depreciation of fruit quality. The most
used means of controlling insect pests is chemical control.
For an efficient control of these insect pests, knowledge of
the entomofauna associated with this crop is required. In
Côte d’Ivoire, the work of Yeboué et al. (2002) made it
possible to make an inventory of okra entomofauna. The
objective of this study, which is part of an integrated
management approach to okra insect pests, is to identify
okra colonizing insects, identify insect pests and damage,
as well as practices to control such insect pests.
between 24° C and 28° C and rainfall reaching 2000 mm
of rain (Saley et al., 2007). The study was carried out on a
peasant plot having a surface area of 500 m².
Figure-1. Location map of the study area.
Biological material
The plant material consisted of okra Abelmoschus
esculentus, koto variety. The animal material was
composed of the species of insects collected at the
different phenological stages of okra (Figure-2).
MATERIAL AND METHODS
Study area
The study was carried out in Anna (Figure-1), a
village located at 4 km of Bingerville between 5°19’ north
latitude and 3°52’ west longitude. The climate is
subequatorial characterized by temperatures ranging
174
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
Methods
Insect catching techniques
Data collection was based on the development
cycle of okra:
- Stage 1 goes from the first day of sowing to the
appearance the first flowers (sowing-flowering);
- Stage 2 goes from the appearance of the first
flowers to the appearance of the first fruits (floweringfruiting);
- Stage 3 goes from the appearance of the first
fruits to ripening and harvesting (fruiting-harvesting)
(Ondo et al., 2014).
Two methods were used: trap catching method
and sight hunting. The trapping system consisted of
colored plates (yellow, blue, white and green) and pitfall
traps on the ground. The plates were placed on the floor
with alternating colors for more efficiency. Each trap color
brought a variety of species and different variations in
abundance and diversity. The pitfall trap was obtained by
digging a hole in the ground where the cup is pushed in
until the rim is level with the ground. Thus laid, they are
more efficient for catching crawling species. Plates and
cups contained a mixture of soapy water, salt and vinegar.
Soapy water was used to wet insects and prevent them
from flying. Salt and vinegar delayed the insect
putrefaction. The second method consisted in removing
the insects by hand, using flexible pliers or using sweep
nets.
Figure-2. Phenological stages of okra.
Technical equipment
The technical equipment consisted of plates of
different colors, disposable plastic cups, sweep nets for
collecting insects. The latter were preserved in pillboxes
containing 70° alcohol. A NIKON COOLPIX S2600
Version 1.0 digital camera was used for shooting. The
identification was done using keys Delvare et al. (1989)
and Roth (1980) keys. A survey sheet on knowledge of
insect pests and control methods helped collect
information from okra growers.
Data collection
The study was conducted over a period of 6
months (July to December 2015) corresponding to 2 okra
cycles. Insect collection was conducted two (2) times per
week. After each collection, the contents of each container
were transferred into a sieve. The different insects were
rinsed with water, placed in pillboxes containing 70°
alcohol on which were written the site, the date of
collection and the phenological stage of the plant. They
were taken back to the laboratory for identification. The
solution contained in the traps was renewed after each
harvest. Insect and damage shooting was carried out. A
survey of chemical pesticides, frequencies, application
doses and protection measures was conducted among 10
okra producers in the study area.
Insect attack rate
The attack rate, expressed as a percentage, was
calculated according to the number of plants attacked in
relation to the total number of okra plants (Souad, 2012).
It plant was considered to be attacked if more than one
third of the leaves were deformed (yellowing and
perforation ...).
𝑭𝒂 =
𝒏×
𝑵
175
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
: Attack rate (%);
: Total number of plants;
: Number of plants attacked
Data analysis
Ecological indices such as relative abundance,
frequency of occurrence, Shannon Weaver diversity index,
and equitability index were calculated.
RESULTS
Abundance and diversity of inventoried insects
The inventory made it possible to obtain 3422
individuals split into 9 orders, 38 families and 53 species.
The flowering- fruiting stage showed the greatest number
of insects (46%) followed by the fruiting-harvesting stage
(28%) and the sowing- flowering stage (26%) (Figure-3).
The application of the Shannon Weaver diversity index
revealed that the flowering-fruiting stage was more
diversified with a diversity index H’= 1.65 followed by the
sowing-flowering stage with H’= 1.51. The diversity index
is lower at the fruiting-harvesting stage with H’= 0.91.
Sowing-Flowering
Flowering-Fruiting
Fruiting-Harvesting
26%
28%
90
80,37
80
Proportion of individuals(%)
Fa
N
n
70
60
50
40
30
20
10
6,25 5,43
3,62 2,57 1,16
0,4 0,11 0,05
0
Orders of insects collected
Figure-4. Abundance of insects collected according
to orders.
Insect pests
Among the insects collected, 2840 were insect
pests belonging to 5 orders, namely the Coleoptera,
Heteroptera, Lepidoptera, Homoptera and Orthoptera
orders represented by 15 families and 17 species (Figure5). The Podagricasp LagriaVilosa and Jacobiascalybica
species were found at all the development stages of okra
while some species were specific to one or two stages
(Table-1). The Shannon diversity index for the FloweringFruiting stage was superior H’= 0.95 to that of the two
others with H’= 0.70 and H’= 0.56.
46%
Figure-3. Distribution of insects collected according to the
phenological stages of okra.
At the three stages, the order of Coleoptera was
the most representative with a rate of 80.37% of the
population. They were followed by Heteroptera 6.25%,
Homoptera 5.43%, Hymenoptera (3.62%), Diptera 2.57%,
Lepidoptera 1.16%, Orthoptera (0.40%), Odonates
(0.11%) and Dictyoptera (0.05%) (Figure-4). Concerning
families, Chrysomelidae were the most important at the
three phenological stages with 65.75% of the population.
The Coccinellidae represented the second largest family
with 6.9%. The Milichidae, Pyrgonorphidae, Braconidae,
Cynipidae, Scoliidae, Bethylidae, Thryreocoridae,
Coreidae and Cetoniidae families were the lowest with
only 0.05% of the stand.
176
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
Abundance of insect pests
At the Sowing-Flowering stage 666 insect pest
belonging to 3 orders were collected, at the FloweringFruiting stage 1310 insect pests belonging to 5 orders were
collected and at the Fruiting-Harvesting stage 864 insect
pests belonging to 3 orders were collected. At the SowingFlowering stage the Heteroptera and Orthoptera orders
were absent and the Lepidoptera and Orthoptera orders
were absent at the Fruiting-Harvesting stage. The
Coleoptera were the most abundant with 85.65% of the
stand. On the other hand, the Orthoptera were the least
abundant with 0.07% of the stand (Figure 6). Concerning
families, the Chrysomelidaeawere the most representative
at the three stages with a rate of 79.22%. This family was
represented by two species Nisotrasp with 22.64% and
Podagricasp with 54.57%. The Coccinellidae family was
the second most represented family after the
Chrysomelidae with a rate of 4.57%. This family was
represented by the Cheiloneneslunata species. The
Pyrgonorphidae family was the least abundant with a rate
of 0.07% represented by the Zonocerusvariegatus species
collected at the Flowering-Fruiting stage.
Identification and assessment of damage to the
different organs
On the leaves, damage was expressed by
perforations caused by Podagricasp and Nisotrasp
(Coleoptera,
Chrysomelidae),
the
larvae
of
Cosmophilaflava
(Lepidoptera,
Noctuidae),
Zonocerusvariegatus (Orthoptera, Pyrgomorphidae). The
flowers were attacked by the Podagricasp and
Dysdercussp (Heteroptera) species. The latter also
attacked the fruits, causing them to dry out and fall
prematurely. Leaf wilting and yellowing were caused by
Homoptera Pseudococcussp (Pseudococcidae) and Aphis
gossypii (Aphididae) (Figure-7). These species would
sting and suck the sap of the plant by transmitting toxins
contained in the saliva. Of the 640 plants surveyed, 358
showed signs of attack, that is, an attack rate of 56%.
Figure-5. Some insect pests found.
177
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
Table-1. Distribution of insect pests depending on the phenological stages
Sowingflowering
+
Floweringfruiting
+
Floweringharvesting
+
Podagricasp(Chrysomelidae)
+
+
+
Lagriavillosa(Ténébrionidae)
+
+
+
Nezaraviridula(Pentatomidae)
-
+
+
Aspaviaarmigera (Pentatomidae)
-
+
+
Dysdercussp (Pyrrhocoridae)
-
+
+
Cletussp (Coreidae)
-
+
+
Elateridae
-
+
+
Aphisgossypii (Aphididae)
+
+
-
Cosmophilaflava(Noctudae)
+
+
-
Zonocerusvariegatus (Pyrgonorphidae)
-
+
-
Curculionidae
-
+
-
Cetoniidae
-
+
-
Nisotrasp(Chrysomelidae)
-
+
-
Pseudococcussp (Pseudococcidae)
+
-
-
Species and Families
Jacobiascalybica (Ciccadellidae)
+: Presence;-: Absence
Proportion of individuals(%)
90
85,63
80
70
60
50
40
30
20
10
6,33
6,54
1,4
0,1
0
Orders of insects pest
Figure-6. Abundance of insect pests depending on orders.
178
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
family which contains predator species of caterpillar and
larvae of Coleoptera. The Diptera of the Syrphidae family
and the CoccinellidaeColeoptera which are predators of
aphids. Formicidae and Carabidae, for their part, play the
role of predator and parasitoids. Species of the
Coccinellidae and Formicidae families were collected at
the three phenological stages (Table-2). Individuals of the
Reduviidae family were collected at sowing-flowering and
flowering-fruiting stages. The Carabidae family was
collected only at the Flowering-Fruiting stage. As for the
Syrphidae family, it was collected at the FloweringFruiting stage and at the Fruiting-Harvesting stage.
Figure-7. Damage observed on okra plants.
Useful insects collected
Some of them were parasitoids and other
predators. These include the heteroptera of the Reduviidae
Phytosanitary control practices
All producers practiced chemical control and the
use of Ocimumgratissimum L., Lamiaceae planted around
ridges. All producers used the same insecticides, namely
K-optimal, whose active ingredients are LambdaCyhalotrine and acetamiprid and Cypercal 50 with
Cypermethrin as active ingredient. These different active
ingredients belong to the Pyrethrinoids and Neonicotinoids families. As for frequencies, these insecticides
were applied once every fortnight. The time of spraying
depended on the availability of market gardens. They did
it very early in the morning or at sunset. To measure the
products, the bottle cap was used. Two caps of the bottle
corresponding to 35 ml on average were diluted in a 15liter backpack sprayer for application. No mixtures of
products for the protection of the crop were made. For the
weeding, an herbicide, namely Sunphosate was used with
Glyphosate as active ingredient.
Table-2. Distribution of useful insects depending on phenological stages.
+
+
+
Flowerin
g-fruiting
+
Fruitingharvesting
-
Not specified
+
+
+
Carabidae
Not specified
-
+
-
Coccinellidae
ExochomusNigromaculatus
-
+
+
Predator
Predator
Predator
Predator
Parasitoid
Parasitoid
Predator
Predator
Coccinellidae
Harmonia quadripunctata
-
+
+
Predator
Coccinellidae
Hyperaspissp
-
+
-
Predator
Coccinellidae
Calviaquatuordeeimguttata
+
+
+
Predator
Orders
Sowing-
Families
Species
Diptera
Reduviidae
Reduviidae
Syrphidae
Nagusta praecatoria
Rhynocorisalbopictus
Not specified
Hymenoptera
Formicidae
Heteroptera
Coleoptera
flowering
Status
+: Presence;-: Absence
DISCUSSIONS
Throughout the okra cycle in Anna, 3422
individuals were collected in 9 orders, 38 families and 53
species. Our results differ from those of Yéboué (1998)
who in a study in Songon on okra inventoried 13268
individuals split into 9 orders and 12 families while Djiéto
et al. (2007) in Cameroon recorded 14 species. The
difference in results could be explained by the period of
study, the abiotic parameters of the sites and the cropping
system. Indeed, the peasant plot used in Anna for the study
was a monocrop plot whereas in Songon it was a
combined cropping system. According to Soro et al.
179
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
(2010) new insects can adapt according to the cropping
period and system. The analysis of the results according to
the different phenological stages of okra shows that the
Flowering-Fruiting stage shows the highest level of insects
collected, that is, 46%, followed by the fruiting-harvesting
stage with 28% and that of sowing-Flowering with A rate
of 26%.This observation was also made by Yeboué et al.
(2002). This could be justified by certain chemicals
produced by the plant that attract both insect pests and
pollinating insects. The colors of the flowers and the
nectar have an attractive power on insects as well. This
observation was confirmed by Balzan and Wackers
(2013). Bertolacini et al. (2011) noted that the presence of
flourishing plants in or adjacent to a crop favors the
maintenance and multiplication of several insect species.
In terms of diversity of species collected, of the
nine (9) orders collected, five (5) namely Coleoptera,
Heteroptera, Homoptera, Lepidoptera and Orthoptera
contained insect pests of okra. These results confirm those
of Yeboué et al. (2002), Djiéto et al. (2007) as well as
Kouassi (2010) who claim that the insect pests of okra
belong to the Coleoptera, Lepidoptera, Heteroptera and
Homoptera orders. For the Heteroptera, four families were
collected: these include Scutelleridae (Calidadregrii),
Pyrrhocoridae (Dysdercussp) and Coreidae (Cletus sp).
These species appeared at the Flowering-Fruiting stage
until harvest. This order contains insects all having stingsucker type mouth parts. When taking food, they sting the
various organs of the plant especially young fruits and
leaves and inject toxic substances containing pathogens
that are the cause of leaf wilt. Similarly, Yéboué (1998)
mentions that the fruits stung by Heteroptera show black
spots at the insertion points of the rostrum. These black
spots are caused by fungi that have penetrated. The attacks
of Dysdercussp on young fruits cause dryness of fruits
which eventually fall (Anonyme, 2008). The FloweringFruiting stage is more diversified than the SowingFlowering
and
the
Fruiting-Harvesting
stages.
Podagricasp was the most abundant insect pest present at
all stages. This species has been designated as a major
insect pest of okra cultivation (Yeboué et al., 2002);
Kouassi (2010). Moreover, the perforations caused by this
Coleoptera result in a reduction in photosynthesis leading
to poor growth of the plant. It is also a vector for okra
mosaic (OMV), which leads to dwarfism and significantly
reduces okra yield (Fauquet et Thouvenel, 1987). The
yellowing of leaves might be a consequence of the feeding
mode of Homoptera by injection of toxic saliva during
their stinging.
Concerning control methods, producers use two
authorized pesticides for market gardening. Producers use
K-optimal and cypercal 50 but do not stick to the
prescribed doses and frequencies. Indeed, it is
recommended to use 10 ml of the product in 15 l of water
to treat 400 m² but they use 35 ml for 15 l of water to treat
500 m 2.
For Bassolé and Ouédraogo (2007), Makondy
(2012) and Akessé et al. (2015), peri-urban agriculture is
dependent on pesticides and other agricultural inputs.
Doses and frequencies of pesticides applied per treatment
are two to three times higher than those recommended
whatever the pesticide. In addition, they do not observe
any protective measures during spraying. This misuse of
pesticides is a danger to producers themselves, consumers,
and the environment.
CONCLUSIONS
The study revealed that okra entomofauna is
highly diversified and varies according to the phenological
stages of the plant. A total of 38 families belonging to 9
orders were identified. At the three stages, the order of
coleoptera was the most representative with a rate of
80.37%. They were followed by Heteroptera 6.25% and
Homoptera 5.43%. Insect pests were more numerous at the
Flowering-Fruiting
stage
with
Podagricasp
(Chrysomelidae Coleoptera) as major insect pest. The
difference in abundance and diversity of insects from one
stage to another could be explained by food preferences.
Some predatory and pollinating species have been
identified (Nagustapraecatoria, Rhynocorisalbopictus,
Harmoniaquadripunctata).The first control method used
by farmers in Anna to cope with insect pests is chemical
control through the use of authorized products but without
abiding by the protective measures. The second method is
the use of an insect repellent plant, Ocimumgratissimum,
as ridge fencing. These practices, which are part of an
integrated control approach, could be promoted.
ACKNOWLEDGEMENTS
This study is part of the research project
"integrated management of diseases and pests of okra,
tomato and rice" funded by the Association of African
Universities.The authors are grateful to them.
REFERENCES
Anonyme.
2008.
Itinéraire
technique
gombo
(Albelmoschus esculentus). Belgique (Bruxelle). p. 67.
Akessé E. N., Ouali-N’goran S-W. M. and Tano Y.
2015.Insectes ravageurs du piment Capsicumchinense
Jacq. (Solanaceae) à Port-Bouët (Abidjan -Côte d’Ivoire) :
Pratiques de lutte par les pesticides chimiques. Journal of
Applied Biosciences. 93: 8667-8674.
Bassolé D and Ouédraogo L. 2007. Problématique de
l’utilisation des produits phytosanitaires en conservation
des denrées alimentaires et en maraîchage urbain et péri
urbain au Burkina Faso: cas de Bobo Dioulasso,
Ouahigouya et Ouagadougou, Rapport de stage. p. 47.
Bertolaccini I., Nunez-Pérez E. and Tipazo E. J. 2011.
Alternative plants hosts of legume aphids and predators in
the province of Léon, Spain. Ciencia. Investigacion
Agraria. 38(2): 233-242.
Balzan M.V. and Wackers F.L. 2013. Flowers to
selectivity enhance the fitness of a host-feeding parasitoid
adult feeding by Tutaabsoluta and its parasitoid
Necremnusartynes. Biologial control. 63: 21-31.
180
VOL. 12, NO. 5, MAY 2017
ISSN 1990-6145
ARPN Journal of Agricultural and Biological Science
©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
Charrier A. 1983. Les ressources génétiques du genre
Abelmoschus (Gombo). Conseil International des
Ressources Phytogénétiques Ed. CIRPG, FAO, Rome. p.
61.
Delvare G. and Aberlenc H. P. 1989. Les insectes
d’Afriques et d’Amérique tropicale. Clés pour la
reconnaissance des familles. Clamecy. p. 302.
Djiéto L., Kouakou B. and Kouassi R. 2007. Contribution
à la connaissance des insectes associés aux cultures
maraichères dans les environs de Yaoundé-Cameroun.
Journal of Biological chemistry. 151-13.
DSDI. 2005. Annuaire des Statistiques Agricoles. Les
Séries Stat’Agri. Direction des Statistiques et de la
Documentation (DSDI). Ministère d’Etat, Ministère de
l’Agriculture. RCI. Abidjan. p. 100.
Fauquet C. and Thouvenel JC. 1987. MaladiesVirales des
Plantes en Côte d’Ivoire. Institut français de recherche
scientifique pour le développement coopération.
Collection Initiations-Documents Techniques n°46.
Editions de l’ORSTOM (Réédition): Paris. 91-98.
Fondio L., Djidji A. H., Kouamé C. N., Aïdara S. and N.
Hala. 2007. Bien cultiver le gombo en Côte d’Ivoire. Fiche
Technique CNRA/CTA. p. 4.
Gnago J. A., Danho M., Agneroh T. A., Fofana I. K. and
Kohou A. G. 2010. Efficacité des extraits de neem
(Azadirachtaindica) et de papayer (Caricapapaya) dans la
lutte
contre
les
ravageurs
du
gombo
(Abelmoschusesculentus) et du chou (Brassicaoleracea) en
Côte d’Ivoire. International Formulae Group. All Right
Reserved. 4: 953-965.
Journal of Biological and Chimical Science. 8(1): 218336.
Roth M. 1980. Initiation à la morphologie, la systématique
et à la biologie des insectes. Paris, O.R.S.T.O.M. p. 211.
Soro S., Diallo A. H., Doumbia M., Dao D. and Tano Y.
2010. Inventaire des insectes de l’igname (Dioscoreaspp):
cas de Bouaké et Toumodi (Côte d’Ivoire). Journal of
Animal and Plant Science. 6(3): 715-723.
Souad A. 2012. Contribution à l’étudebio-écologique de l’
Apatemonachus (Fabricius, 1775) d’Ouargla, Mémoire de
fin de cycle pour l’obtention du diplôme d’ingénieur
d’Etat en Science Agronomique, Protection des végétaux
(option: Entomologie), Université KoasdiMerbah-Ouargla.
p. 102.
Saley B.M., Tanoh R., Koffi F. K., Oga M. S. & Kouadio
H. 2007. Variabilité Spatio-temporelle de la pluviométrie
et son impact sur les ressources en eaux souterraines: cas
du district d’Abidjan (Sud de la Côte d’Ivoire), université
de cocody Abidjan, UFR STRM p. 18.
Yéboué N. L. 1998. Inventaire des insectes des cultures
maraîchères dans la région d’Abidjan. Mémoire présenté
pour l’obtention du diplôme d’études approfondies
d’entomologie générale. p. 96.
Yeboué N.L., Foua- Bi K. and Kehé M. 2002. Inventaire
de l’entomofaune associé à la culture du gombo
(Abelmoschusesculentus (L) en zone forestière de Côte
d’Ivoire. Agronomie Africaine. 14(3): 165-181.
Kouassi A. E. 2010. Etude comparée de l’efficacité des
extraits aqueux de graine deneen (Azadirachataindica
jass) et de feuille d’eucalyptus (Eucalypyuscamaldulensis)
dans la lutte contre les insectes du gombo
(Abelmoschusesculentus L). Mémoire de fin d’étude pour
l’obtention
du
diplôme
d’agronomie,
ESA,
Yamoussoukro. p. 80.
Makondy A. E. R. 2012. Contrôle de la qualité des denrées
alimentaires traitée avec les pesticides: Cas de la tomate.
Mémoire présenté et soutenu en vue de l’obtention du
diplôme de professeur de l’enseignement secondaire
deuxième grade, Université de Yaoundé I, p. 70.
N’Guessan K., P. 1987. Contribution à l’étude de
l’enroulement du gombo, Mémoire DEA d’Ecologie
Tropicale (option végétale), Université Nationale de Côte
d’Ivoire. p. 42.
Ondo O. P., Gatarasi T., Minko D. O., Kouamegoye M. D.
and Kavers C. 2014. Etude de la dynamique des
populations d’insectes sur la culture du riz Nerica dans les
conditions du Mosuku, Sud- Est du Gabon (Franceville),
181