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Begoude B.A.D.,University of Pretoria | Begoude B.A.D.,Institute Of Recherche Agricole Pour Le Developpement Irad | Slippers B.,University of Pretoria | Wingfield M.J.,University of Pretoria | Roux J.,University of Pretoria
Forest Pathology

In Cameroon, native Terminalia spp. represent an important component of the forestry industry, but limited information is available regarding the fungal pathogens that affect them. The Botryosphaeriaceae are endophytic fungi and latent pathogens that can result in wood stain, cankers, die-back and death of trees, particularly when trees are under stress. The aim of this study was, therefore, to identify and characterize the Botryosphaeriaceae occurring as endophytes of Terminalia spp. in Cameroon, as part of a larger project to identify potential pathogens of these trees in the country. Samples were collected from three Terminalia spp. in the Central, Southern and Eastern Regions and the resultant Botryosphaeriaceae were identified using morphology and DNA sequence comparisons for the ITS and tef 1-α gene regions. Furthermore, inoculation trials were conducted to consider the relative pathogenicity of the isolates collected. The majority of isolates (88%) represented species of Lasiodiplodia, including L. pseudotheobromae, L. theobromae and L. parva. The remaining isolates were identified as Endomelanconiopsis endophytica. Pathogenicity trials on young T. mantaly and T. catappa trees revealed that L. pseudotheobromae was the most pathogenic species followed by L. theobromae. © 2010 Blackwell Verlag GmbH. Source

Sonwa D.J.,Center for International Forestry Research | Sonwa D.J.,International Institute Of Tropical Agriculture | Weise S.F.,Biodiversity International | Nkongmeneck B.A.,University of Yaounde I | And 2 more authors.
Agroforestry Systems

The distribution and composition of the tree component inside cocoa agroforests plays an important role in the economic and ecological services offered by these plantations. The presence of these plant components appears to be influenced by several factors controlling the introduction and management of associated plants inside cocoa agroforests. To date, few studies have tried to evaluate the horizontal and vertical distribution of plants inside cocoa plantations in Cameroon. This study determines the structure of cocoa plantations in Southern Cameroon. Field data were collected in 60 cocoa plantations belonging to 12 villages located along a contiguous gradient of market access, population density and resource use intensity in the humid forest zone of southern Cameroon. This study area comprises (i) the sub-region of Yaoundé, (ii) the sub-region of Mbalmayo, and (iii) the sub-region of Ebolowa. Market access, population density and resource use intensity all decreased from the first to the third sub-region. For cocoa and associated plants, we quantified (1) the density (2) the individual number, the species composition and the group uses of plants (edible, timber, medicinal, etc…) distribution across strata, and (3) the basal area in the 60 cocoa plantations located in the three main sub-regions. Results are presented for each sub-region and the whole study area. The paper develops cocoa agroforest typologies and discusses possible implications of cocoa agroforest structure diversity in the achievement of economic and ecological services. © 2016 Springer Science+Business Media Dordrecht Source

Begoude Boyogueno A.D.,University of Pretoria | Begoude Boyogueno A.D.,Institute Of Recherche Agricole Pour Le Developpement Irad | Slippers B.,University of Pretoria | Perez G.,University of Pretoria | And 2 more authors.
Fungal Biology

In this study, we determined the genetic diversity of 126 isolates representing both Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae, collected from Theobroma cacao and Terminalia spp. in Cameroon, using simple sequence repeat (SSR) markers. SSR alleles showed clear genetic distinction between L. theobromae and L. pseudotheobromae, supporting their earlier separation as sister species. Both L. theobromae and L. pseudotheobromae populations from Cameroon had high levels of gene diversity, moderate degrees of genotypic diversity, and high levels of gene flow between isolates from T. cacao and Terminalia spp. There was no evidence for geographic substructure in these populations across the region studied, and the SSR alleles were randomly associated in both species, suggesting outcrossing. The significant levels of aggressiveness, evolutionary potential represented by high levels of diversity, outcrossing and gene flow between geographically and host defined populations, identify these fungi as high-risk pathogens for their native and non-native hosts in Cameroon. © 2011 The British Mycological Society. Source

Menzepoh S.B.,Institute Of Recherche Agricole Pour Le Developpement Irad
Biotechnology, Agronomy and Society and Environment

In the Zambezian region of Africa, tuber orchids are renowned for their food, medicinal and economic values. In central Africa and in Cameroon in particular, socio-economic role of orchids is still to be documented. The current paper focuses on two orchids, Habenaria keayi Summerh. and Habenaria zambesina Rchb.f. which tuber and roots respectively are used to prepare a food called "napssié" or ground meat by the Bagam tribe in the subdivision of Galim, Western region of Cameroon. The paper also mentions their socio-economic role, threat and pleads for their domestication. Source

Teinkam D.D.,Institute Of Recherche Agricole Pour Le Developpement Irad | Meyer C.,CIRAD - Agricultural Research for Development | Monniaux D.,CNRS Physiology of Reproduction and Behaviors | Laine A.-L.,CNRS Physiology of Reproduction and Behaviors | And 2 more authors.
Livestock Research for Rural Development

A study on the progesterone profile (P4) in plasma during pregnancy and the effect of some reproductive parameters was carried out on station at Yaounde using 23 local dwarf goats of the forest zone of Cameroon. During pregnancy the curve of P4 in this local breed had a classical shape with three phases: an increasing phase during the first 60 to 70 days, then a plateau till the 130 th day followed by a fall before parturition that occurred around the 145 th day. The average P4 concentrations in the plateau ranged from 8.7 ± 2.7 ng/ml on day 60 th to 9.1 ± 0.8 ng/ml on day 130 th of gestation. The sex of the kids, the parity of the doe and the kidding season did not affect the plasma concentration of P4. The number of foetuses (litter size) appeared to affect P4 concentrations during the first 30 days of gestation (P<0.05). This influence was more effective for single birth and twins, and less with triplets. For females with P4 concentrations beyond 13 ng/ml between the 20 th and the 140 th day of pregnancy, 2 or 3 foetuses were obtained. Two groups of females with 2 foetuses were distinguished: those with high P4 concentrations (13.4 ± 3.6 ng/ml on 100 th day) and those with low values (7.7 ± 1.6 ng/ml on 100 th day), suggesting the existence of different populations within the dwarf goats. It was concluded that P4 concentrations alone could not permit an early and accurate prediction of the litter size, but high concentrations could help predict multiple births. Source

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