Hervé K. Koua | Felix Houphouet Boigny Abidjan University-- Ivory Coast, West Africa (original) (raw)
Books by Hervé K. Koua
This is Volume 1 - Issue 7 of the Journal of Research in Biology. Journal of Research in Biology ... more This is Volume 1 - Issue 7 of the Journal of Research in Biology.
Journal of Research in Biology is an international scientific journal committed to the development and spread of research in Biological sciences. It accepts research articles with affiliation to biological science from all around the globe and publishes them in the journal. The submitted articles are peer-reviewed by experts in the field and editorial board members.
Papers by Hervé K. Koua
The impact of terrestrial thiocyclam hydrogen oxalate (Evisect®) sprays an insecticide used again... more The impact of terrestrial thiocyclam hydrogen oxalate (Evisect®) sprays an insecticide used against Coelaenomenodera lameensis the major pest of oil palm on pollinating insects was evaluated. Samples of pollinators were collected from both male and female oil palm inflorescences on untreated and treated plots. Means and standard deviations of the insects collected were compared by analysis of variance test and the post hoc NewmanKeuls. The results showed that insect populations of all species on female inflorescences (Elaeidobius kamerunicus, E. plagiatus, E. subvittatus, E. bilineatus, E. singularis, Microporum congolense, M. dispar, Prosoestus minor, P.sculptilis and Atheta Burgeoni) were significantly influenced by the spraying of Evisect® whilst the insects present on the male inflorescences were sensitive to the pesticide according to anthesis stages. In addition three of the four major pollinators of oil palm (E. kamerinicus, E. subvittatus, E. plagiatus and E. singularis) wer...
The invasive species, Bactrocera invadens Drew Tsuruta & White, is a major pest of mangoes (Mangi... more The invasive species, Bactrocera invadens Drew Tsuruta & White, is a major pest of mangoes (Mangifera indica L.) and sweet oranges (Citrus sinensis Osbeck) in Côte d’Ivoire.. A better knowledge of its biology can improve the control of this new destructive pest. The study was carried out under semi-natural conditions of orchard and in laboratory at the insectarium of Cocody
Sciences & Nature, 2010
Spatio-temporal distribution of Coelaenomenodera lameensis Berti and Mariau, 1999, pest of palm o... more Spatio-temporal distribution of Coelaenomenodera lameensis Berti and Mariau, 1999, pest of palm oil tree (Elaeis guineensis Jacquin, 1963) was carried out on 1226 ha of an industrial plantation at Toumanguié (south-east of Côte d'Ivoire). Temporal distribution of population established the existence, according to the years, of favorable periods of Coelaenomenodera lameensis infestations. Eight peaks of infestation were observed during 24 months. Infestation cycles proceeds each 90 days. Spatial distribution of the infestations revealed experimental plots having recorded between 0 and 8 months of infestation during the 2 years of investigation. This distribution proved to be independent of the age of the plots. Infestations were also independent of abiotic factors (rainfall, temperature and relative humidity). Larvae at stages 1, 2, 3 and 4 are mostly responsible of the damages observed in the fields.
Flies are major pests of fruits in Cote d'Ivoire. The fight against these pests is achieved b... more Flies are major pests of fruits in Cote d'Ivoire. The fight against these pests is achieved by using several methods including parasitoids. The study was carried out under orchards semi naturel conditions in southern, central, northern areas of Cote d'Ivoire. An inventory was made after a mass breeding in box containing fruits placed in sterilized and humidified sand. The fruits were covered by muslin. Four species of fly hosts of the parasitoids were listed: Bactrocera invadens, Ceratitis quinaria, Ceratitis cosyra and Dacus bivittatus. Eight species of parasitoids belonging to the Hymenoptera order, Braconidae family and three genera were identified: Diachasmimorpha(D.) tryoni, D. fullawayi, Fopius(F.) arisanus, F. caudatus, F. vandenboschi, F. silvestrii, Psyttalia (P)lounsburyi and P. incisi. The most abundant species were D. tryoni, D. fullawayi, F. arisanus and F. Caudatus. Fruits infested by females of B. invadens and C. cosyra were presented to females of the four pa...
American Journal of Experimental Agriculture, Jan 10, 2012
Pollination of oil palm tree is mainly entomophilous. The inflorescences of this plant lodge many... more Pollination of oil palm tree is mainly entomophilous. The inflorescences of this plant lodge many insects. The identification and quantification of these insects have proven ability to hold their pollination. The entomofauna of female and male inflorescences was inventoried and quantified at La Mé, a station of CNRA, the National Center of Agronomic Research of Côte d'Ivoire (West Africa) for a period of 2 years. The insects of the male inflorescences were listed at the beginning, the full and the end of anthesis on 1536 spikelets of 384 male inflorescences. For the insects of female inflorescences, 96 inflorescences were covered with a muslin sheath. The insects arriving on these inflorescences were captured in 2 days corresponding to anthesis length, during 10 minutes per hour, from 6 am to 6 pm. Species Elaeidobius sp., Microporum sp., Prosoestus sp. and Atheta burgeoni were common and regular present regardless of inflorescence type. Species Gabrius sp., Thrips sp., Anthocoride sp., Lithargus sp. and the bees (Nomia sp. and Apis mellifera) were rarely observed in female inflorescences. Elaeidobius kamerunicus and Prosoestus sp. were more abundant on the female than on the male inflorescences. The higher level of insects was observed in full anthesis on male inflorescences whereas among female inflorescences it was noted at the first day of flowering. Knowledge of the insect fauna of oil palm inflorescences according to different stages of flowering allows better management of pollination.
The pollination of the oil palm is assured mainly by the insects. The most effective are Elaeidob... more The pollination of the oil palm is assured mainly by the insects. The most effective are Elaeidobius kamerunicus and Elaeidobius plagiatus . Declining populations of pollinating insects in the palm oil plantation is often the cause of the low yields observed in the production of seeds. The study of the biology of these beetles has been conducted in the laboratory (27.43 ± 0.74 ° C and 75.16 ± 2.54 HR). The average of life expectancy was of 32.02 ± 12.43 days for Elaeidobius plagiatus and 59.18 ± 8.53 days for Elaeidobius kamerunicus . The total cycle time was 10.27 ± 0.34 and 8.38 ± 0.12 days respectively for E. kamerunicus and E. plagiatus . The number of eggs laid by female is of 57.64 ± 8.29 eggs for E. kamerunicus against 29.56 ± 5.29 for E. plagiatus . Knowledge of the biology of these insects is vital for better management of oil palm yields.
This is Volume 1 - Issue 7 of the Journal of Research in Biology. Journal of Research in Biology ... more This is Volume 1 - Issue 7 of the Journal of Research in Biology.
Journal of Research in Biology is an international scientific journal committed to the development and spread of research in Biological sciences. It accepts research articles with affiliation to biological science from all around the globe and publishes them in the journal. The submitted articles are peer-reviewed by experts in the field and editorial board members.
The impact of terrestrial thiocyclam hydrogen oxalate (Evisect®) sprays an insecticide used again... more The impact of terrestrial thiocyclam hydrogen oxalate (Evisect®) sprays an insecticide used against Coelaenomenodera lameensis the major pest of oil palm on pollinating insects was evaluated. Samples of pollinators were collected from both male and female oil palm inflorescences on untreated and treated plots. Means and standard deviations of the insects collected were compared by analysis of variance test and the post hoc NewmanKeuls. The results showed that insect populations of all species on female inflorescences (Elaeidobius kamerunicus, E. plagiatus, E. subvittatus, E. bilineatus, E. singularis, Microporum congolense, M. dispar, Prosoestus minor, P.sculptilis and Atheta Burgeoni) were significantly influenced by the spraying of Evisect® whilst the insects present on the male inflorescences were sensitive to the pesticide according to anthesis stages. In addition three of the four major pollinators of oil palm (E. kamerinicus, E. subvittatus, E. plagiatus and E. singularis) wer...
The invasive species, Bactrocera invadens Drew Tsuruta & White, is a major pest of mangoes (Mangi... more The invasive species, Bactrocera invadens Drew Tsuruta & White, is a major pest of mangoes (Mangifera indica L.) and sweet oranges (Citrus sinensis Osbeck) in Côte d’Ivoire.. A better knowledge of its biology can improve the control of this new destructive pest. The study was carried out under semi-natural conditions of orchard and in laboratory at the insectarium of Cocody
Sciences & Nature, 2010
Spatio-temporal distribution of Coelaenomenodera lameensis Berti and Mariau, 1999, pest of palm o... more Spatio-temporal distribution of Coelaenomenodera lameensis Berti and Mariau, 1999, pest of palm oil tree (Elaeis guineensis Jacquin, 1963) was carried out on 1226 ha of an industrial plantation at Toumanguié (south-east of Côte d'Ivoire). Temporal distribution of population established the existence, according to the years, of favorable periods of Coelaenomenodera lameensis infestations. Eight peaks of infestation were observed during 24 months. Infestation cycles proceeds each 90 days. Spatial distribution of the infestations revealed experimental plots having recorded between 0 and 8 months of infestation during the 2 years of investigation. This distribution proved to be independent of the age of the plots. Infestations were also independent of abiotic factors (rainfall, temperature and relative humidity). Larvae at stages 1, 2, 3 and 4 are mostly responsible of the damages observed in the fields.
Flies are major pests of fruits in Cote d'Ivoire. The fight against these pests is achieved b... more Flies are major pests of fruits in Cote d'Ivoire. The fight against these pests is achieved by using several methods including parasitoids. The study was carried out under orchards semi naturel conditions in southern, central, northern areas of Cote d'Ivoire. An inventory was made after a mass breeding in box containing fruits placed in sterilized and humidified sand. The fruits were covered by muslin. Four species of fly hosts of the parasitoids were listed: Bactrocera invadens, Ceratitis quinaria, Ceratitis cosyra and Dacus bivittatus. Eight species of parasitoids belonging to the Hymenoptera order, Braconidae family and three genera were identified: Diachasmimorpha(D.) tryoni, D. fullawayi, Fopius(F.) arisanus, F. caudatus, F. vandenboschi, F. silvestrii, Psyttalia (P)lounsburyi and P. incisi. The most abundant species were D. tryoni, D. fullawayi, F. arisanus and F. Caudatus. Fruits infested by females of B. invadens and C. cosyra were presented to females of the four pa...
American Journal of Experimental Agriculture, Jan 10, 2012
Pollination of oil palm tree is mainly entomophilous. The inflorescences of this plant lodge many... more Pollination of oil palm tree is mainly entomophilous. The inflorescences of this plant lodge many insects. The identification and quantification of these insects have proven ability to hold their pollination. The entomofauna of female and male inflorescences was inventoried and quantified at La Mé, a station of CNRA, the National Center of Agronomic Research of Côte d'Ivoire (West Africa) for a period of 2 years. The insects of the male inflorescences were listed at the beginning, the full and the end of anthesis on 1536 spikelets of 384 male inflorescences. For the insects of female inflorescences, 96 inflorescences were covered with a muslin sheath. The insects arriving on these inflorescences were captured in 2 days corresponding to anthesis length, during 10 minutes per hour, from 6 am to 6 pm. Species Elaeidobius sp., Microporum sp., Prosoestus sp. and Atheta burgeoni were common and regular present regardless of inflorescence type. Species Gabrius sp., Thrips sp., Anthocoride sp., Lithargus sp. and the bees (Nomia sp. and Apis mellifera) were rarely observed in female inflorescences. Elaeidobius kamerunicus and Prosoestus sp. were more abundant on the female than on the male inflorescences. The higher level of insects was observed in full anthesis on male inflorescences whereas among female inflorescences it was noted at the first day of flowering. Knowledge of the insect fauna of oil palm inflorescences according to different stages of flowering allows better management of pollination.
The pollination of the oil palm is assured mainly by the insects. The most effective are Elaeidob... more The pollination of the oil palm is assured mainly by the insects. The most effective are Elaeidobius kamerunicus and Elaeidobius plagiatus . Declining populations of pollinating insects in the palm oil plantation is often the cause of the low yields observed in the production of seeds. The study of the biology of these beetles has been conducted in the laboratory (27.43 ± 0.74 ° C and 75.16 ± 2.54 HR). The average of life expectancy was of 32.02 ± 12.43 days for Elaeidobius plagiatus and 59.18 ± 8.53 days for Elaeidobius kamerunicus . The total cycle time was 10.27 ± 0.34 and 8.38 ± 0.12 days respectively for E. kamerunicus and E. plagiatus . The number of eggs laid by female is of 57.64 ± 8.29 eggs for E. kamerunicus against 29.56 ± 5.29 for E. plagiatus . Knowledge of the biology of these insects is vital for better management of oil palm yields.