Antifungal activities of five Combretaceae used in Togolese traditional medicine

Five species of Combretaceae growing in Togo were investigated for their antifungal activity against 20 pathogenic fungi (10 yeast and 10 filamentous fungi). The five hydroethanolic extracts of Terminalia glaucescens and Anogeissus leiocarpus appeared to be the most active, their MICs ranging from 0.25 mg/ml to 4 mg/ml. The results confirm the traditional therapeutic properties of these plants.     

Evaluation of integrated crop management strategies employed to cope with Striga infestation in permanent land use systems in southern Benin

Striga hermonthica and S. gesnerioides pose serious threats to cereal and cowpea production, endangering peoples' livelihoods on the Abomey plateau, Benin. A 2-year joint experiment was undertaken with farmers in two hamlets to investigate the potential of managing sowing dates of cowpea, sorghum transplanting, and trap cropping as ways of increasing agricultural production and reducing Striga damage. Early sowing of cowpea failed due to dry spells. Late sowing reduced cowpea yield due to water deficiency at the end of the growing season. Transplanting sorghum seedlings raised in fertilised or Striga-free nurseries doubled or tripled cereal yield and substantially reduced S. hermonthica infestation compared to direct early-sown sorghum. Transplanting sorghum from plant hills to fill gaps was unsuccessful. Trap crops such as cowpea and groundnut increased subsequent maize yield. Trap cropping had only a small effect on S. hermonthica infestation. The very poor soils in Somè central were a major constraint upon yield improvement to acceptable levels even after the introduction of the new crop (and Striga) management methods.     

Influence of Panicum maximum ecotypes on plant root growth and soil chemical characteristics after 3-year study in Soudanian region of West Africa

A study was carried out to compare the influence of four Guinea grass ecotypes (Panicum maximum) differing in their morphological, physiological, and agronomical traits on soil fertility in Soudanian region of West Africa. Plants were sown in a randomized complete block design with four replicates and cultivated during three successive years under a cut-and-carry regime without any fertiliser use. A natural fallow served as the control. Soil samples were collected before and after cultivation, and analyzed for pH, organic carbon, nitrogen, available P, and exchangeable cation contents. Aerial plant production was quantified and analyzed for N, P, and K content to estimate the uptake of these nutrients. Root biomass, depth, and distribution were also measured. Data were analyzed through ANOVA. After 3 years of cultivation, soil pH under plants did not vary but C and N concentrations declined from the initial levels. Owing to their deep rooting systems, two ecotypes can recycle nutrients apparently from deeper soil layers. While these ecotypes could be used for ley pastures in savannah regions of West Africa, maintenance fertiliser applications would be required to prevent nutrient depletion under a cut-and-carry regime. Further studies to test the efficacy of farmyard manure in providing these nutrients seem warranted.     

Parataxonomy,perceived dynamics and diversity of uses of two Detarium species in Benin (West Africa)

The contribution of species providing non-timber forest products to the livelihoods of local communities is well established. However, this contribution may be limited by the existence of confusion while dealing with close relative species. This is particularly the case for Detarium microcarpum Guill & Perr. and D. senegalense J.F.Gmel. The objectives of this study were to (1) identify the criteria used by local communities to differentiate D. microcarpum and D. senegalense, (2) determine local communities’ perception of the past dynamics of the two species and (3) assess the diversity of uses of both species. Data on differentiation criteria, perceived variation in the species abundance, and the different uses were collected using individual semi-structured interviews (n?=?914 informants). The relative frequency of citation and the use-value were calculated. The Chi-square test, correspondence analysis and generalized linear model were used for statistical analyses. Informants used fourteen criteria to differentiate the two species. The predominant criteria were the shape of the seed (87.86%) and the shape of the fruit (67.86%). Most of the informants reported that the populations of D. microcarpum (61.80%) and that of D. senegalense (60.12%) have regressed. In total, 168 use-reports were enumerated for the two species with 19 shared use-reports. We concluded that local communities use a variety of criteria to differentiate both species, the most popular being morphological traits of the fruits. Both species shared several use-reports (11.31%). However, their populations have declined. The documented uses for both species provide preliminary information for their future food uses and drug discovery.

     

Effect of cow colostrum on the performance and survival rate of local newborn piglets in Benin Republic

The effect of bovine colostrum, including its thermally labile compounds, on the survival and growth performance of local breed piglets reared by their mother, in Benin, was evaluated over a 49-day trial. Three groups of 16 piglets, stemming from two primiparous sows belonging to a unique traditional farm, were respectively fed for the first 48 h of life with either bovine colostrum heated to 85 °C for 30 min, or thawed bovine colostrum, or colostrum from the mother. Thereafter, the animals that received bovine colostrum turned back to their mother. At day 21, almost all piglets from the group that received heated colostrum died. The highest total weight gain was obtained in the group that received thawed bovine colostrum (P???0.01), followed by the group left with the mother. Corresponding average daily gains (ADGs) were 56, 34 and 2 g/day, respectively (P???0.05). At the end of the trial, the treatment effect was highly significant on the survival of piglets (100% in the thawed colostrum group vs. 00 and 50%, respectively, in the heated colostrum group and in the group left with the mother). At day 49, numerically higher weight and ADGs were obtained in the group that received thawed cow colostrum. Thawed bovine colostrum improved the growth performance and piglet survival in the local pig breed in Benin, probably owing to thermally labile components. Bovine colostrum may be used in our farms in order to reduce pre-weaning mortality, improve the profitability of livestock farmers, and ensure survival of traditional farms. The use of bovine colostrum on farms could be facilitated by collaboration between pig farmers and bovine farmers. It could also be facilitated by the creation of a colostrum bank.     

Rhamphicarpa fistulosa, a parasitic weed threatening rain-fed lowland rice production in sub-Saharan Africa - A case study from Benin

Expansion of the facultative parasitic plant Rhamphicarpa fistulosa as a weed of rain-fed lowland rice was studied in 2007 on a national level (Benin) by repeating a survey from 1998. Wider species’ distribution was investigated in 2008. Current and potential impact and management strategies were investigated through farmer surveys and pot experiments. Out of 36 cultivated inland valleys visited across Benin, eight were found to be infested with Rhamphicarpa. Out of nine inland valleys inspected in 1998, Rhamphicarpa was found in five in 2007, compared with only three in 1998. Farmers estimated Rhamphicarpa-inflicted yield losses could exceed 60% and indicated that heavily infested fields are abandoned. In a pot experiment with a wide infestation range, the popular cultivar Gambiaka, combining resistance with sensitivity, showed a mean relative yield loss (RYL) of 63%. Parasitic Rhamphicarpa biomass (PRB), the difference between the above-ground biomass produced with and without a host, was suggested as indicator for infection level of this facultative parasite and hence as a practical measure for host resistance. Genetic variation in resistance and tolerance levels was observed among rice cultivars, but fertilizer applications significantly reduced parasite numbers, biomass and effects, cancelling out such genotypic differences. Depending on the tolerance level of the cultivars, the PRB only accounted for 3.7-38.8% of the average parasite-inflicted host biomass reductions, indicating phytotoxic effects of Rhamphicarpa infection.R. fistulosa is an apparently increasing constraint to rain-fed lowland rice in Benin, threatening rice production in the wider region. The use of resistant and tolerant cultivars, combined with fertilizer applications could reduce Rhamphicarpa infections and mitigate negative effects on rice yields.