ABSTRACT
The present study conducted at the farm of INP-HB Yamoussoukro
is part of the search for new alternatives to chemical pesticides, especially
insecticides. It was to test the efficacy of aqueous extracts of neem seeds
(Azadirachta indica Juss) and eucalyptus leaves (Eucalyptus
camadulensis) having respectively active ingredient, azadirachtin and
cineol on insect pests of okra (Abelmoschus esculentus L.). We
compared on experimental plots (randomized block) okra, four treatments. They
include: a check (T0), a registered chemical insecticides "K-OPTIMAL" (T1)
whose contents are lambda-cyhalothrin 15 g / l and Acetamiprid 20 g / l, a neem
seed extract (T2 ) and another aqueous extract of eucalyptus leaves (T3). The
neem seed extract is obtained after grinding almonds in fruits of neem and then
mixed with water for 24 hours. The eucalyptus extract was in turn, obtained
after the leaves crushed and then boiled in water. Treatments were applied at
intervals of six days and observations three days after each treatment.
Observations were made on live insects and fruit production. After analyzing
the results, it appears that the chemical insecticide control flea beetles,
aphids, red cotton bugs and Anomis flava but does not control
whiteflies and jassids. The aqueous extract of neem seed control whiteflies,
jassids, aphids, red cotton, Anomis flava but do not control flea
beetles. The aqueous extract of eucalyptus leaves has had a moderate impact on
whiteflies, aphids and jassids but has not effet on other insects observed. Of
all the applied treatment, only plots treated with chemicals insecticide
recorded the highest number of fruits that have not been attacked insect
pests.
Key words: aqueous extract of plants,
neem, eucalyptus, okra.
III
SOMMAIRE
RESUME I
ABSTRACT II
AVANT PROPOS VII
REMERCIEMENTS VIII
LISTE DES TABLEAUX IX
LISTE DES FIGURES X
SIGLES ET ABREVIATIONS XII
LISTE DES ANNEXES XIII
DEDICACE XIV
INTRODUCTION 1
PARTIE I: GENERALITES
I.PRESENTATION DE LA ZONE D'ETUDE 3
1. Situation géographique 3
2. Milieu physique. 3
2.1. Climat 3
2.2. Végétation 4
2.3. Sol 4
2.4. Hydrographie 4
3. Présentation du site d'expérimentation
4
3.1. Situation géographique 4
3.2. Végétation et hydrographie locale 5
II.GENERALITES SUR LES PESTICIDES ET LES CULTURES
MARAICHERES 5
1. Pesticides 5
1.1. Définition de pesticides . 5
1.2. Insecticides chimiques 6
1.2.1. Regroupement selon l'origine 6
1.2.2. Regroupement selon le type d'activité et le mode
d'action 7
1.2.3. Interaction ou synergie des polluants 7
1.2.4. Phénomène de résistance aux
pesticides 7
1.3. Biopesticides 9
1.3.1 Spécificité 9
1.3.2 Biodégradabilité 9
1.2.3 Résistance 9
1.4. Cas du neem (Azadirachta indica
Juss) 10
1.4.1. Description 10
1.4.2. Composition et propriété chimique 11
1.4.3. Mode d'action sur les insectes 11
1.4.4. Utilisations 11
1.5. Cas de l'eucalyptus (Eucalyptus
camaldulensis) 12
1.5.1. Historique 12
1.5.2. Description 13
1.5.3. Composition chimique 14
1.5.4. Mode d'action de composés terpéniques 15
1.5.5. Utilisations 15
2. Cultures maraichères 15
2.1. Principaux groupes 15
2.2. Classification 16
2.3. Intérêts de la culture des plantes
maraîchères 16
2.3.1. Intérêt nutritionnel 16
2.3.2. Intérêt économique 16
2.3.3. Intérêt social 17
2.3.4. Intérêt environnemental 17
2.4. Gombo 17
2.4.1. Origines 17
2.4.2. Description 17
2.4.3. Ecologie 18
2.4.4. Utilisations 19
2.4.5. Maladies et ennemis 20
2.4.5.1. Principaux ravageurs 20
2.4.5.2. Agents de maladies foliaires 22
| 
