The study of improvement of solar water disinfection by photosensitization with coumarin extracts of some plants of Rutaceae family (Citrus limonum, Citrus paradisi and Citrus sinensis) shows an inhibition of 90% for fecal coliforms after 30 minutes of sunshine. Complete inhibition is noted after 60 minutes. In water not treated and exposed to the sunlight, an inhibition of 32% was noticed after 60 minutes. The photosensitizing activity noted in these extracts is due to the presence of coumarins. These molecules in presence of light absorb the energy and pass from the ground state to the excited state. Returning to the ground state, the stored energy is transferred to the oxygen, which then passes from the ground state, triplet, to the excited state, singlet, and inhibits the coliforms present in water.
Cassava crop yield is reduced by numerous constraints among which African root and tuber scale Stictococcus vayssierei Richard, a devastator of cassava and other crops. This scale damage causes a decrease in amount and quality of cassava tuberous roots in case of serious infestations. It is in this context that a study on influence of the population density African root and tuber scale on cassava (Manihot esculenta CRANTZ) was conducted to determine the damage influence on the yields of two improved varieties and one local variety in different agro-ecological areas of Beni Territory. The objective of this study is to identify among these improved and a local varieties those can be grown in an agro ecological area where the population of african root and tuber scale has no harmful influence on tuberous root yields. To achieve this objective, we verified the hypothesis according to which a good knowledge of the population density helps to determine the rational growing site of cassava varieties. The experiment was conducted in four sites under average altitudes (800-1200 m) and high altitudes (1200-1400 m) with variable infestation rates. The populations of African root and tuber scale with various stages of life and the marketable tuberous root production of each of the varieties as well as climatic factors were determined every three months for two years. The randomized complete block with four repetitions was used. The cluster analysis findings on the effects of the population density of the scale on the yields of these three varieties show that improved varieties were more infested than the local variety under mild altitude. Consequently, their yields were low compared to the local variety. Butamu and Mvuazi improved varieties produced low yields under mild altitudes where there were serious infestations of African root and tuber scale. The yields obtained from these two improved varieties under mild altitudes were respectively 13.1 T/ha and 18.8T/ha compared to Mbayilo local variety that produced 22.5 T/ha at 12 months after plantation (12MAP) on second year screening. Serious infestations of scale under mild altitudes were the cause for low yields of these improved varieties. In high altitude agro ecological areas where the population density of African root and tuber scale was low. Butamu improved variety yielded 25.3 T/ha compared to Mbayilo local variety that produced 37 T/ha at 12MAP on second year of screening. Our results show that the tuberous root production of the released improved varieties of cassava decreases in agro ecological areas with serious infestations of the scale. For the choice of the growing site of the improved varieties, Beni Territory high altitudes with low infestation of African root and tuber scale seem to be better indicated since Mvuazi variety produced 63.8 T/ha.
Cassava is, economically, one of the most important root and tuber crops in Africa. However, its production is compromised by a large number of diseases and pests among which the african root and tuber scale (Stictococcus vayssierei Richard). This insect causes damage that can result in a low yield and non tuber formation of cassava in case of serious infestation. It is in this context that a study on screening cassava (Manihot esculenta CRANTZ) genotypes was carried out for resistance to African root and tuber scale in different agro ecological areas of Beni (North Kivu province, in East of the Democratic Republic of Congo). The objective of the study is to assess resistance to African root and tuber scale of 40 varieties of cassava supplied by the International Institute of Tropical Agriculture and the National Institut of Research Agriculture whose five local are found on the spot after survey. To reach this goal, we verified the hypothesis that stipulates that the introduction of new varieties of cassava in the country is a strategy to fight African root and tuber scale. All varieties were placed in four sites under mild altitudes (1000-1200 m) and high altitudes (1200-1400 m). The populations of African root and tuber scale in various stages of life and the tuberous root production of each variety were assessed every three months for two years in a randomized block experimental with four repetitions. The screening ANOVA findings showed significant effects, S. vayssierei infested the majority of tested varieties. Nevertheless, principal components analysis (PCA) and cluster analysis identified a reconciliation of tolerance vis-
The aim of this study is to verify if the endemic cholera around Lake Kivu is consecutive to the colonization of plankton by V. cholerae. We undertook the search of V. cholerae germs in samples of water from this Lake then trying their elimination in removing zooplankton by filtration. Thus, from November 2011 to June 2013, we analyzed 64 samples of coastal water from 3 different sites of the Lake Kivu; one site in a rural basin (Ishungu) and 2 sites in a urban basin (Bukavu ). The detection and numeration of V. cholerae were made by culture methods completed by biochemical tests. Filtration was done thanks to zooplankton
The use of great apes Pharmacopoeia or zoo-pharmacognosy is a very promising strategy for the treatment of human diseases due to the phylogenetic proximity of humans and non-human primates (NHP) as Bonobos. In total, more than 40 direct fields' observations of bonobos have been performed for five months. A high number of direct observations were recorded in August followed by September while there was less observations in June. The average size and composition of the group for August is estimated at 19 individuals with 8 males, 9 females and 2 young whereas the size recorded in September was of 12 individuals including 5 males, 6 females and 1 young. Physicochemical and blood-biochemical analysis results performed on bonobos urine within their natural habitat shown the presence of bilirubin in some urine specimens (a formation of an azo derivative with a diazonium salt). The presence of a lot of leukocytes in urine is an indication of Plasmodium infection since we are in Malaria endemic regions. These results confirm the evidence of great ape pathological condition and then these could be considered as a biological model for testing and/or validating the self-medication hypothesis and the anti-hemolytic effects of plants consumed by NHP that could be profitable to the sickle cell individuals. The survey revealed that the pharmacopoeia of bonobos of Lomako Nature Reserve consists of 35 plant species. The bioassay test showed that Treculia africana, a plant being part of the diet of the bonobos, inhibits the sickling of red blood cells in vitro in hypoxic conditions and can serve as a source of bioactive metabolites for promoting an antisickling nutritherapy in Democratic Republic of the Congo. The relationship between the pharmacopoeia of apes and sickle cell anemia is an original approach. Thus, it opens up new perspectives for the treatment of this hemoglobinopathy through modulating effects of secondary metabolites of plant origin on the epi-genome.
The present study carried out in Kisangani area on the biodiversity of Rodents and Soricomorpha mixed culture fields in some villages of the surroundings of Kisangani. The main goal was to evaluate the specific richness of rodents and Soricomorpha in these habitats. In 8.955 nights traps, by using the technique of trapping out of grid using the Traps Victor Rat Traps, Special Museum, Sherman and traditional trap, we collected 301 specimens of small Mammals belonging to two orders: Rodents (288 specimens: 95.6%) and Soricomorpha (13 specimens: 4.31%). These animals are subdivided in 12 species. Nannomys cf grata was the most abundant with 168 trapped animals (55.81%). Nannomys cf grata, Lemniscomys striatus (Linnaeus, 1758) and Lophuromys dudui (Verheyen, Hulselmans & Dierckx, 2002), Praomys minor (Hatt, 1934) and Praomys cf jacksoni are field species who are harmful for crops. The diversity index of Simpson "D", Shannon Wiener "H" and the equitability "E" were respectively 0.6625, 0.2358 and 0.6577. The calculated values of these indices show a low diversity with a bad distribution of trapped animals between different species in the studied crop cultivation fields. All identified species are common in the Kisangani area. It is therefore necessary to set up a control policy in order to fight against these culture destructors in Democratic Republic of the Congo.