Cameroon Journal of Experimental Biology最新文献

{"title":"Above-ground biomass and nutrient accumulation in the tropical rainforests of southern Cameroon: effects of logging","authors":"A. Ibrahim, A. Ze, J. Ntonga","doi":"10.4314/CAJEB.V6I1.56880","DOIUrl":"https://doi.org/10.4314/CAJEB.V6I1.56880","url":null,"abstract":"Impact of logging activities on nutrient cycling in tropical rainforests of southern Cameroon has been little investigated. A study was initiated by the Tropenbos-Cameroon Programme to determine changes in above-ground phytomass and nutrient stock following selective logging in Ebom rainforest of Southern Cameroon. One hundred and twelve (112) trees were sampled in three undisturbed plots of 10m x10m. Their diameters and dry mass were determined. Allometric equations (Y = a + b*D + c*D 2 and Y = a’*D b’ ), relating dry mass of foliage, branches, trunks with barks, and total biomass to diameter at breast height (DBH), were developed to estimate the above-ground tree biomass of undisturbed and disturbed forests. Understorey biomass was estimated by harvesting method. The total above-ground tree biomass is about 583 t.ha-1dry mass in the undisturbed forest. This contains 302 t.ha-1 C and a nutrient capital of 8888 kg.ha-1N, 6953 Ca, 2337 K, 436 P, 311 Mg and 30 kg. ha-1 Na. The stores of nutrient in the above-ground biomass was about 2 (311 and 175 kg ha-1) to 16 (436 and 28 kg. ha-1) times higher than in the top soil stock, respectively for Mg and available P. The losses of carbon and nutrients associated with timber extraction represented less than 7% of store in the above-ground biomass for all nutrients. This means that the impact of logging in the Ebom rainforest remains low. However, additional research is needed on nutrient input in the forest from outside as well as on the impact of logging on nutrient leaching in order to get a complete picture of the nutrient cycles. Key-words: phytomass, nutrient pools, logging, allometric equations, tropical rainforest, Southern Cameroon","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"200 1","pages":"49-62"},"PeriodicalIF":0.0,"publicationDate":"2010-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76970103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hermaphrodisme morphologique et dioécie physiologique dans une population de Piliostigma reticulatum (D.C.) HOSCHT (Caesalpinioideae)","authors":"M. Dao, B. Diallo, C. Kaboré-Zoungrana","doi":"10.4314/CAJEB.V6I1.56876","DOIUrl":"https://doi.org/10.4314/CAJEB.V6I1.56876","url":null,"abstract":"Piliostigma reticulatum (Caesalpiniaceae) est une espece dont les gousses sont fourrageres et font l’objet d’un important commerce au Sahel. L’etude porte sur la morphologie et l’evolution florales dans le peuplement de Budtenga en zone nord soudanienne du Burkina Faso. Suite aux observations preliminaires, 5 individus a fleurs dites femelles et 5 autres a fleurs dites mâles ont ete choisies. Sur chaque arbre 300 fleurs reparties entre le sommet, le milieu et la base du houppier ont ete echantillonnees. L’observation a concerne la morphologie florale, l’anatomie des organes sexuels sous une loupe binoculaire. Ensuite, un comptage du nombre d’ovules et une etude de la viabilite in vitro des grains de pollens apres coloration a la fushine ont ete realises. Nos resultats montrent que la population etudiee est morphologiquement hermaphrodite mais fonctionnellement dioique. Les individus a fleurs dites femelles montrent un ovaire bien developpe contenant en moyenne 49 ovules. Le stigmate est globuleux et change de coloration du vert jaune au brun apres l’epanouissement des fleurs. Leurs etamines sont atrophiees sous forme de staminodes et depourvues de grains de pollen viables in vitro. Les individus a fleurs dites mâles montrent un pistil avec un ovaire reduit, un stigmate allonge qui ne change pas de coloration et des etamines bien developpees avec des antheres contenant des grains de pollen viables in vitro. La taille des fleurs dites mâles n’est pas significativement differente de celle des fleurs dites femelles. La dioecie fonctionnelle mise en evidence pourrait etre le debut d’une evolution vers un hermaphrodisme ou vers une dioecie stricte en fonction de l’intensite des pressions anthropiques. Mots cles : Caesalpinioideae; Piliostigma reticulatum ; Morphologie florale; Hermaphrodisme ; Dioecie Piliostigma reticulatum (Caesalpiniaceae) is a fodder species because of its pods which are subject of a major trade in the Sahel. The morphology and floral development in the population of Budtenga at north Sudanian zone of Burkina Faso have been carried out. After preliminary investigations, we chose 5 trees which bear female flowers and 5 others which bear male flowers were selected for studies. 300 flowers were collected from the top, the middle and the base of the crown on each tree. We observed floral morphology, anatomy of sexual organs in a binocular magnifying glass. Then we counted the number of ovules and the viability of pollen grains from female and male flowers after colored with the  fushine has been tested in vitro. Our results showed that the species was morphologically hermaphroditic but functionally dioecious. Female flowers showed a well developed ovary containing an average of 49 ovules. The stigma was globular and changed color from green-yellow to brown after the opened flowering stage. The stamens were atrophied and devoid of viable pollen  grains in vitro. Male flowers showed a pistil with a reduced ovary a stigma that did not cha","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74812909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological and water-use efficiencies of sorghum-groundnut intercrop","authors":"M. Omoko, L. C. Hammond","doi":"10.4314/CAJEB.V6I1.56874","DOIUrl":"https://doi.org/10.4314/CAJEB.V6I1.56874","url":null,"abstract":"In order to compare water-use efficiency of sole crops and intercrops, 2 experiments were conducted in 2 consecutive years with sorghum ( Sorghum bicolor L. Moench) and groundnut ( Arachis hypogaea L.) on a loamy, Grossarenic Paleudult. In a randomized block, split-plot design, sorghum (SS), groundnut (GG), sorghum/groundnut intercrop (SG) were subjected to 4 replicates of 4 water managements as main treatments (trt): (1) Optimum irrigation, (2) deficit irrigation allowing stress on sorghum, or (3) on groundnut, (4) rainfed. All crops were seeded in rows at a density of 256000 (SS), 160000 (GG), 256000 + 160000 (SG, year 1), 157000+102000 (SG, year 2) plants/ha. Soil water status was monitored and ET calculated all over the growing seasons. Dry matter (DM) and grain yields (GY) were determined at physiological maturity for each crop. Sorghum GY was very high, ranging from 3.55 (trt 4) to 8.03 (trt 1) Mg/ha in sole crop, and from 2.71 to 6.27 Mg/ha in intercrop. Groundnut GY was very high in sole crop (3.76 to 6.54 Mg/ha), but was very depressed in intercrop (0.13 to 3.26 Mg/ha). Mean Total Land Equivalent Ratio (TLER) was 1.14 for DM and 1.11 for GY, showing a 14 and 11% advantages over sole cropping. But these advantages disappeared when the amount of water used was taken into account in the Total Land Water Use Equivalency Ratio (TLWUER). The overall mean TLWUER were 1.01(irrigation) and 0.99 (seasonal ET) for DM, 0.98 and 0.96 for GY, indicating no advantage of intercropping over sole cropping. Nevertheless, based on water use ratios, intercropping was more water use efficient than sole crops. The contrasting results between the TLER and TWUER may imply that the yield advantage of intercropping was not attributable to its overall improved water use ratio but rather to its higher seasonal water use. Key words: Intercropping, Biological efficiency, Water use efficiency, TLER, TLWUER","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"24 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2010-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77959143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Caractérisation agro-morphologique et moléculaire de cultivars locaux de niébé (Vigna unguiculata) du Burkina Faso","authors":"Jérémie Tinga Ouedraogo, M. Sawadogo, Jean-Baptiste Tignegre, I. Drabo, Didier, Balma","doi":"10.4314/CAJEB.V6I1.56878","DOIUrl":"https://doi.org/10.4314/CAJEB.V6I1.56878","url":null,"abstract":"Les ecotypes locaux de niebe collectes a la fin des saisons pluvieuses 2000 et 2001 ont ete separes (pour chaque ecotype) par les paysans en un ou plusieurs composantes selon la couleur du tegument ou de l’oeil, la texture ou la taille de la graine. Les melanges sont plus frequents quand les cultivars ont la meme couleur. De 122 cultivars collectes, 1.4 composante en moyenne a ete detectee. Les evaluations faites en plein champ en contre saison et en saison pluvieuse ont revele que les cultivars appeles Beng-yaanga ou Beng-maasga sont de long cycle et sensibles a la photo periode. Plusieurs caracteres agro-morphologiques ont ete determines et permettent d’operer des choix judicieux pour des utilisations aux fins de production ou de recherche. La caracterisation moleculaire realisee grâce a l’amplification PCR avec des amorces SCAR et la technique AFLP sur un nombre restreint de cultivars a confirme l’efficacite des deux methodes pour caracteriser les cultivars mais la technique AFLP permet une analyse beaucoup plus fine. Mots cles : Purete, niebe, caracterisation moleculaire, Burkina. The local ecotypes of cowpea collected at the end of the rainy seasons 2000 and 2001 have been separated (for each ecotype) by farmers in one or more components according to the color of integument or the eye, texture or size of the seed. The mixtures are more frequent when the cultivars have the same color. From 122 cultivars collected, averaging 1.4 components has been detected. The field assessments were made during dry and rainy season have shown that cultivars called Beng-yaanga or Beng-maasga has late maturing period and sensitive to the photo period. Several agromorphological characteristics have been determined and can be used to select cultivars for production or research. The molecular characterization was tested using two techniques namely PCR amplification with primers SCAR and AFLP technology on a limited number of cultivars. The profiles have confirmed the effectiveness of two methods for characterizing cultivars but AFLP technology allows a more detailed analysis. Key words: Purity, cowpea, molecular characterization, Burkina","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"433 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77240210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Foraging behaviour of Apis mellifera adansonii and its impact on pollination, fruit and seed yields of Citrullus lanatus at Nkolbisson (Yaoundé, Cameroon)","authors":"Michelson Azo’o Ela, J. Messi, F. T. Fohouo, Joseph Lebel, Tamesse, S. Kekeunou, J. Pando","doi":"10.4314/CAJEB.V6I1.56879","DOIUrl":"https://doi.org/10.4314/CAJEB.V6I1.56879","url":null,"abstract":"Honeybee ( Apis mellifera adansonii Latreille (Hymenoptera: Apidae)) foraging activity was observed to evaluate its impact on pollination, fruit and seed yields of Citrullus lanatus (Thunb) Mansf (Cucurbitaceae) in the area of Yaounde (Cameroon). Two lots of 775 female flowers were marked according to the presence or the absence of a protection for insect visits. The honey bees’ activity, the fruit set, the number of seeds per fruit were recorded. A. m. adansonii primarily foraged for nectar on C. lanatus throughout the whole blooming period of each plant and pollen collection was low. The mean maximum number of workers foraging at the same time was 331 ± 173 (n= 41) per 1000 flowers. The mean foraging speed was 10.20 ± 2.75 (n = 154) flowers per minute. The fruit set and the number of seeds per fruit of unprotected female flowers were significantly higher than those of female flowers protected from insects. A. m. adansonii pollination contributed 70.14% to the fruit set and seed yields. The conservation of A. m. adansonii colonies near C. lanatus population must be encouraged. Key words: Citrullus lanatus, Apis mellifera adansonii , pollination, yields, Cameroon. L’activite de butinage d’ Apis mellifera adansonii Latreille (Hymenoptera : Apidae) a ete etudiee afin d’evaluer son impact sur la pollinisation, les rendements fruitiers et grainiers de Citrullus lanatus (Thunb) Mansf (Cucurbitaceae) a Yaounde (Cameroun). Deux lots ont ete determines par le marquage de 775 fleurs femelles differant selon la presence ou l’absence de protection vis-a-vis des visites d’insectes. Le rythme saisonnier d’activite des abeilles domestiques, le taux de fructification des fleurs femelles et le nombre de graines par fruit ont ete evalues. A. m. adansonii butinait les fleurs de C. lanatus tout au long de la periode de floraison de chaque plante. Les butineuses prelevaient intensement le nectar pendant que la collecte du pollen etait reduite. Le plus grand nombre d’ouvrieres butinant simultanement etait de 331 ± 173 (n = 41) par 1000 fleurs. La vitesse moyenne de butinage etait de 10.20 ± 2.75 (n = 154) fleurs par minute. Le taux de fructification et le nombre moyen de graines matures par fruit des fleurs non protegees de l’activite des insectes etaient significativement eleves que ceux des fleurs femelles protegees. La contribution d’A. m. adansonii sur les rendements fruitiers et grainiers de C. lanatus etait de 70.14% grâce a l’action pollinisatrice des ouvrieres. La conservation des colonies d’A. m. adansonii a cote des populations de C. lanatus en fleurs doit etre encouragee. Mots cles: Citrullus lanatus, Apis mellifera adansonii, pollinisation, rendements, Cameroun","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"62 1","pages":"41-48"},"PeriodicalIF":0.0,"publicationDate":"2010-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78551189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Description Des Champignons Ectomycorhiziens Du Genre Scleroderma De Quelques Formations Forestieres Du Burkina Faso","authors":"Kadidia B. Sanon, M. Dianda, T. Guissou, A. Bâ","doi":"10.4314/CAJEB.V5I2.51942","DOIUrl":"https://doi.org/10.4314/CAJEB.V5I2.51942","url":null,"abstract":"Au cours de prospections dans les formations forestieres du Sud et de l’Est du Burkina Faso, des champignons ectomycorhiziens du genre Scleroderma ont ete recoltes sous quatre Caesalpinioideae, Afzelia africana Sm., Isoberlinia doka Craib. & St apf., I. dalziellii Craib. & Stapf, et Berlinia grandiflora (Vahl) Hutch.; un Dipterocarpaceae, Monotes kerstingii Gilg. et deux Phyllanthaceae, Uapaca guineensis Mull. & Arg. et U. somon Aubr. & Lean. La description morphologique des carpophores et des spores de ces champignons a permis d’identifier deux especes definies (Scleroderma dictyosporum Pat et S. verrucosum Pers.) et quatre especes morphologiques non determinees (Scleroderma sp1, Scleroderma sp2, Scleroderma sp3 et Scleroderma sp4). Cependant, le sequencage de l’ITS (Espacer Interne Transcrit) et l’analyse phylogenetique de certains isolats (donnees non presentees) revelent plutot trois groupes d’especes morphologiques, S. verrucosum, S. dictyosporum, et Scleroderma sp2, suggerant que les especes du genre Scleroderma peuvent presenter diverses morphologies. Des isolements ont permis de mettre en culture 22 isolats, dont au moins un isolat par espece. L’etude de l’aptitude mycorhizogene de quelques isolats a montre que les Sclerodermes sont  peu specifiques avec un large spectre d’hote, et seraient donc des candidats indiques pour la mise en place de programme de mycorhization controlee en Afrique tropicale seche. Mots-cles : Ectomycorhizes, Scleroderma, Morphologie, Burkina Faso. During prospectings in the forests vegetation of the South and East of Burkina Faso, the ectomycorrhizal fungi of the genus S cleroderma were collected under four Caesalpinioideae, Afzelia africana Sm ., Isoberlinia doka Craib. and Stapf ., I. dalziellii Craib. and Stapf, and Berlinia grandiflora (Vahl) Hutch.; one Dipterocarpaceae, Monotes kerstingii Gilg. and two Phyllanthaceae, Uapaca guineensis Mull. and Arg. and U. somon Aubr. and Lean. The morphological description of sporocarps and spores of these fungi allowed identifying two defined species ( Scleroderma dictyosporum Pat. and S. verrucosum Pers.) and four morphological species not described (Scleroderma sp1, Scleroderma sp2, Scleroderma sp3 and Scleroderma sp4). However, the sequencing of the ITS (Internal Transcribed Spacer) region of some isolates (data not presented) reveal rather 3 groups of morphological species; S. verrucosum, S. dictyosporum and Scleroderma sp2 , suggesting that the species of the genus Scleroderma can present diverse morphologies. Twenty-two (22) isolates are maintained in pur culture with at least an isolate by specie. Survey of ectomycorrhizal status of some isolates showed that Scleroderma are less specific with a broad host range and would thus be candidates indicated for the implementation of controlled mycorhization program in dry tropical Africa.","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"114 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90384895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact de l’utilisation des antibiotiques sur la sensibilité des bactéries pathogènes de poules dans la ville de Ngaoundéré","authors":"L. T. Ngoune, K. S. Tanedjeu, C. Mbofung","doi":"10.4314/CAJEB.V5I2.51937","DOIUrl":"https://doi.org/10.4314/CAJEB.V5I2.51937","url":null,"abstract":"L’utilisation non controlee d’antibiotiques en elevage conduit a la selection des germes resistants avec de multiples consequences nefastes telles que la recrudescence des infections, l’augmentation de la mortalite et la baisse de la productivite. L’objectif de ce travail est de faire l’etat des lieux sur l’utilisation des antibiotiques en elevage de poules et d’evaluer leurs consequences sur la sensibilite des bacteries pathogenes. Pour ce faire nous avons d’abord mene une enquete pour apprecier les types et les quantites d’antibiotiques utilises. Par la suite, nous avons isole des bacteries pathogenes par la methode des stries sur milieu non selectif. La sensibilite aux antibiotiques a ete determinee par la methode de diffusion sur milieu solide. Les resultats de l’enquete ont montre que douze antibiotiques sont couramment utilises en elevage. Il s’agit de l’oxytetracycline (6000g/mois), les sulfamides (4000g/mois), le furaltadone (2600g/mois), l’erythromycine (1000g/mois), la norfloxacine (615g/mois), la flumequine (500g/mois), la colistine (470g/mois), la penicilline (80g/mois), la streptomycine (80g/mois), la tylosine (60g/mois), la neomycine (25g/mois) et l’ampicilline (20g/mois). Leur cout est evalue approximativement a 1 200 000 francs CFA par mois. Par ailleurs vingt souches de bacteries pathogenes ont ete identifiees et appartiennent aux genres Aeromonas (1 souche/20), Bordetella (1/20), Cedecea (1/20), Citrobacter (1/20), Proteus (5/20), Pseudomonas (1/20), Salmonella (9/20) et Vibrio (1/20). Elles ont presente des resistances face a l’ampicilline (90% de resistance), l’erythromycine (100%), la penicilline (100%), le cefixime (60%), la tetracycline (45%), le chloramphenicol (45%), l’amoxicilline (40%), la streptomycine (40%), la nitrofurantoine (40%), l’acide oxolonique (25%) et les sulfamides (20%). Mots cles : Antibiotiques, resistance, poule de chair, poule pondeuse, Ngaoundere, Cameroun.  The non controlled used of antibiotics in poultry farming leads to resistant germs selection with disastrous consequences as the upsurge of the infections, the increase of mortality and the decrease of productivity. The aim of this work was to evaluate the impact of the use of antibiotics on pathogenic bacteria sensibility in poultry farming. Thus, we made an investigation firstly to appreciate the types and the quantities of antibiotics used, and secondly to make some withdrawals in every farms. Thereafter, we isolated the pathogenic bacteria by the streaking method on non selective media. The antibiotic sensitivity test was determined by the agar diffusion method. Results showed twelve antibiotics most commonly used in poultry farming are oxytetracyclin (6000g/month), sulphamides (4000g/month) and furaltadone (2600g/month), followed by erythromycin (1000g/month), norfloxacin (615g/month), flumequin (500g/month), colistin (470g/month), penicillin (80g/month), streptomycin (80g/month), tylosin (60g/month), neomycin (25g/month) and ampicillin (20g/","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81010875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthèse et Etude pharmacologique de la 4-phényl-l, 5-benzodiazépin-2-one et ses dérivés","authors":"P. Kanyonga, A. Zellou, Y. Cherrah, E. Essassi","doi":"10.4314/CAJEB.V5I2.51949","DOIUrl":"https://doi.org/10.4314/CAJEB.V5I2.51949","url":null,"abstract":"L'etude de l’activite pharmacologique de la 4-phenyl-1,5-benzodiazepin-2-one, 4-phenyl-1,3,4,5-tetrahydro-1,5-benzodiazepin-2-one, 4-phenyl-1,5-benzodiazepin-2-thiole synthetisees dans notre Laboratoire montrent que ces produits ne sont pas toxiques aux doses therapeutiques et qu'ils sont doues d'effets sedatif, myorelaxant, anxiolytique mais, ne presentent pas d’effet hypnotique, ni cataleptique. Cependant, ces trois produits de synthese potentialisent a des degres differents l'effet hypnotique du Nesdonal. Mots cles: 1,5-benzodiazepine, synthese, toxicite aigue, activite psychotrope. The study of the pharmacological activity of the 4-phenyl-1,5-benzodiazepin-2-one, 4-phenyl-1,3,4,5-tetrahydro-1,5-benzodiazepin-2-one, 4-phenyl-1,5-benzodiazepin-2-thiol synthesized in our laboratory showed that these products are not toxic at therapeutic doses and possess sedative, muscle relaxant, anxiolytic effects, but do not present any hypnotic, or catalepsy effect. However, these three products potentiate synthesis to different degrees of the hypnotic effect Nesdonal.","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90225622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"E cology MYCOTROPHIE ET CONNAISSANCES PAYSANNES DES ESSENCES FERTILITAIRES DANS LES AGROFORETS A BASE DE CACAOYERS DU SUD CAMEROUN","authors":"N. Bidzanga, B. Fotsing, V. Agoume, B. À. Madong, N. O. Awana, L. Zapfack","doi":"10.4314/CAJEB.V5I2.51944","DOIUrl":"https://doi.org/10.4314/CAJEB.V5I2.51944","url":null,"abstract":"A comparison of land uses in the South Cameroon area shows that cocoa agroforests are less damaging the environment than the other land uses. In the respect, investigations to assess farmers’ knowledge of the contribution of associated trees in the soil fertility status in their cocoa farms were carried out in two ecologically contrasting locations of southern Cameroon in March 2008. 20 cocoa farms were selected per location. In each cocoa farm, all the associated trees were inventoried and their fine roots sampled to assess their mycorhizal status. Individual farmers were asked to rank amongst the identified trees the ten top indicators of fertile soils and to indicate their contributing functional attributes to that effect. The species’ frequency and distributions were calculated. Our findings revealed that there were 52 different species in cocoa systems of the forest savanna transition zone against 195 species in the humid forest zone. The frequency distribution indicated a predominance of exotic trees such as Dacryodes edulis, Mangifera Indica, Elais guineensis, Citrus sinensis, Citrus reticuka and Persea americana than indigenous species in both sites. Farmers’ classification of species according to their fertilising potentials pertained to some tree functional attributes mainly rooting habits, leaf size and leaf area. Comparison between farmers’ ranking and ranking based on species’ mycotrophy showed no major differences. Further investigations taking into consideration physico-chemical and other biological aspects influencing soil fertility are necessary to ascertain farmers’ perceptions.","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78249273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Agro-ecological differentials in soybean crop evapotranspiration and implications for adaptation to climate change.","authors":"E. Molua","doi":"10.4314/CAJEB.V5I2.51945","DOIUrl":"https://doi.org/10.4314/CAJEB.V5I2.51945","url":null,"abstract":"This study estimated soybean crop evapotranspiration from weather data using the cropwat model. The effects of reference evapotranspiration, crop coefficients, and yield response factor were quantified for three different agroecological zones in Cameroon. The evapotranspiration of soybean was observed to be 281.03 mm in the farming district of Ambam, 387.7 mm in Bamenda and 605.3 mm in Garoua, indicating pronounced differences in the agro-ecologies. Across the three regions studied, rainfall pattern determines soil water reserves and crop water uptake. In the farming zones of Bamenda and Ambam, water requirement for soybean are met by the rainfall. In the northern region of the country, irrigation needs are high. As a consequence, actual crop evapotranspiration is greatest in the hot dry zone of Garoua and lowest in the cool humid region of Bamenda. From this study it could be concluded that coping with climatic variations and future climate change will require complementary irrigation as well as improved crop management practices.","PeriodicalId":9401,"journal":{"name":"Cameroon Journal of Experimental Biology","volume":"4 1","pages":"87-95"},"PeriodicalIF":0.0,"publicationDate":"2010-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78664009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}