Discrimination of citrus tristeza virus (CTV) strains using Mexican lime/citrange Troyer combinations (Citrus poncirus/Citrus trifoliata x Poncirus sinensis)

Two strains of citrus tristeza virus (CTV) were studied for six years in Yaounde in the forest zone of Cameroon. These strains, SNCL2 and SNCL4, were characterized on Lisbon lemon in Nyombe in thelittoral zone of Cameroon. They were inoculated onto combinations of Mexican lime/citrange Troyer. The virulent strain SNCL2 induced a lower lateral growth of the trunk of stocks and scions of six yearsold combinations. These observations were made three years after inoculation. Tristeza symptoms could not allow for differentiation between the two strains of CTV

Removal of faecal bacteria and nutrients from domestic wastewater in a horizontal surface flow wetland vegetated with Echinochloa pyramidalis

The aim of this study was to evaluate the removal of faecal bacteria and nutrients from domestic wastewater, in surface flow wetlands vegetated with Echinochloa pyramidalis. Horizontal surface flow (HSF) wetlands were fed with primarily treated domestic wastewater at organic loading rates varying from 20.74 to 27.15 g BOD/m2/day for two consecutive years. Water samples were collected at two weeks interval from the inflow and the outflow of the treatment wetlands for physicochemical and faecal bacteria analyses. Physicochemical parameters with highest removal rates were total suspended solids (TSS, 62-80%), Nitrates (57-73 %) and PO4-3 (57-84 %). Faecal indicators reductions of 1.4 and 0.3 log units (1st year) and 1.15 and 0.65 log units (2nd year) were respectively recorded in the vegetated and the control wetlands. Reductions of total coliforms, faecal coliforms and faecal streptococci were significantly higher in the vegetated wetland than in the non-vegetated control in both seasons of the first year. In the contrary, there was no significant difference in the removal rates of faecal indicators between vegetated wetland and the non-vegetated control during the dry season of the second year. Wetlands vegetated with E. pyramidalis was proven to be continuously efficient in the removal of faecal indicators for the two years of study, with no significant differences between the seasons of the year and between the years.Key words: Wastewater, wetlands, Echinochloa pyramidalis, faecal bacteria removal, nutrients removal

Effects of salinity stress on seedlings growth, mineral nutrients and total chlorophyll of some tomato (Lycopersicum esculentum L.) cultivars

In this study, six cultivars of tomato (Lycopersicum esculentum L. var. Jaguar, Xewel, Nadira, Lindo, Mongal and Ninja) were evaluated. They were subjected to salt stress during vegetative growth. Three concentrations of salt solution 50, 100 and 200 mM NaCl and the control (Wacquant nutrient solution) were used in irrigation. The total chlorophyll, the dry weight of seedlings (roots dry weight, stems dry weight and leaf dry weight), the plant height and the mineral nutrient concentrations (Na+, K+ and Ca2+) were determined. The results showed that the salt treatments increased significantly Na+ concentrations in roots, stems and leaves of plants, whereas K+ and Ca2+ concentrations and K+/Na+ selectivity ratio of plants were decreased in all tomato cultivars. The results also revealed after six weeks of salt treatments that the dry weight partitioning and the plant height decreased significantly in Jaguar, Xewel, Nadira and Mongal with increasing salinity. Jaguar, Xewel, Nadira and Mongal can therefore be considered as salt-sensitive cultivars which tolerance level ranges from 0 to 50 mM NaCl. The Lindo and Ninja plant height was less affected by salt stress than the four other cultivars. In Ninja, the moderately salt-tolerant cultivar, the growth parameters were significantly reduced at 100 mM NaCl. The supply of mineral nutrient solution with NaCl did not affect significantly leaf total chlorophyll content and plant organs dry weight of Lindo at 100 mM NaCl suggesting that it was relatively more tolerant in saline medium than other cultivars studied. The Lindo cultivar could be cultivated in environments with relatively moderate salinity.Keywords: Growth, Lycopersicum esculentum, tolerance, mineral nutrients, plant organsAfrican Journal of Biotechnology Vol. 9(33), pp. 5366-5372, 16 August, 201

Heterosis and combining ability in a diallel cross of okra (Abelmoschus esculentus (L.) Moench)

A diallel analysis on 8 pure lines of Abelmoschus esculentus was done at 3 sites in Cameroon (Dibang, Yaoundé and Yagoua) in a randomized complete block design, with 3 replications, to estimate both the heterosis and the combining ability. The heterosis over mid-parent and the combining abilities were significant for all the studied traits. Reciprocal effects were observed for all traits, except for the 50 % flowering day. The best results of heterosis, over mid-parent, were recorded by combination 1 x 2 for seeds number per pod parameter (54.78 %). These parameters are supposed to improve the characters in okra.Key-words : Okra, heterosis, diallel analysis

Pulmonary tuberculosis in the central prison of Douala, Cameroon

Objective: To determine the prevalence of and factors associated with pulmonary tuberculosis (PTB) in an urban prison in sub-Saharan Africa.Design: A cross-sectional survey. Setting: The Central Prison of Douala, Cameroon. Results: Two thousand four hundred and seventy four (87.4%) out of 2830 inmates underwent screening. Twenty seven (1.1%) of the inmates were under treatment for smear-positive PTB on commencement of the survey while 60 (2.4%) were diagnosed with smear and/or culture-positive PTB during the active case finding, resulting in a point prevalence of PTB of 3.5%. HIV seroprevalence in inmates without clinical signs of PTB was 111/1067 (10.4%) while it amounted to 6/24 (25%) in PTB patients. In multiple stepwise regression analysis, a low BMl, a prison stay of ≤12 months, and a history of previous incarceration were positively associated with PTB. Conclusion: The study results confirm the high prevalence rates of PTB in prison populations and underscore the need for urgent preventive measures. East African Medical Journal Vol. 83(1) 2006: 25-3

Mineral nutrient status, some quality and morphological characteristics changes in peanut (Arachis hypogaea L.) cultivars under salt stress

Peanut (Arachis hypogaea L.) is considered to be one of the most important crops which thrive in newly reclaimed sandy soils as a leguminous crop of high nutritive value and a source of edible oil. Our study tested the effects of different salt levels on mineral nutrient partitioning (Na+, K+, Mg2+, Ca2+, P and N) and some quality (dry weight and leaf relative water content) and morphological (plant height, number of leaves) characteristics of peanut commercial cultivars. Four peanut cultivars (Mbiah, Ngondo, Pyrieur and Vanda) were used in this experiment. Three concentrations of salt solution including 50, 100 and 200 mM NaCl and the control (Wacquant nutrient solution) were used in irrigation. The pot experiment was arranged in completely randomized design with four replicates. The leaf relative water content (LRWC) provoked by the salinity in nutrient solution decreased from 85.08 to 83.43%, 87.82 to 85.30%, 85.81 to 78.20% and 85.90 to 79.70% in Mbiah, Ngondo, Pyrieur and Vanda cultivars respectively. The results showed that the salt stress reduced significantly (p<0.05) the plant height in Pyrieur cultivar from 40.49 to 21.45 cm, the number of leaves from 11.2 to 7.0, the dry weight of roots from 0.15 to 0.11 g Plant-1, the dry weight of stems from 0.37 to 0.15 g Plant-1 and the dry weight of leaves from 0.46 to 0.19 g Plant-1. Similar results were obtained in Vanda cultivar where the supply of nutrient solution with salinity reduced significantly (p<0.05) the plant height from 38.26 to 26.30 cm, the number of leaves from 12.5 to 7.5, the dry weight of roots from 0.14 to 0.03 g Plant-1, the dry weight of stems from 0.36 to 0.12 g Plant-1 and the dry weight oh leaves from 0.46 to 0.19 g Plant-1. The results also revealed that K+, Mg2+, Ca2+, P, N, K+/Na+ and Ca2+/Na+ uptake of peanut plant organs were significantly (p<0.05) reduced with increasing salinity in Pyrieur, Vanda and Mbiah except for total N accumulation in plant organs of Mbiah. The plant height, the number of leaves, the dry weight and the mineral nutrient uptake were not significantly (p>0.05) reduced under salt stress in Ngondo plant organs except at high salt-treated (200 mM NaCl). The Ngondo cultivar was observed to have relatively higher tolerance on average of all growth parameters and mineral nutrient status than others. This finding suggested that the Ngondo cultivar could be used to highlight the newly salt cultivated sandy soils in arid, semi-arid regions and similar environments across Cameroon.Key words: Arachis hypogaea, growth parameters, mineral nutrient, plant organs, salt stress

Caractérisation hydrologique, morpho-métrique et physicochimique d’un hydrosystème urbain : le lac municipal d’Ebolowa (Sud-Cameroun)

La dégradation de la qualité des eaux de surface, constitue l’un des problèmes environnementaux majeurs auquel l’humanité est confrontée. Elle se caractérise par l'asphyxie des écosystèmes aquatiques, conséquence de la prolifération anarchique des algues qui consomment tout l'oxygène nécessaire à la vie de ces écosystèmes. Au Cameroun, de nombreuses sources de pollution des eaux ont été identifiées, mais l'absence d’une véritable stratégie de gestion des déchets est à l’origine de la dégradation de la qualité des eaux de surface. Dans l’optique d’évaluer le Lac Municipal d’Ebolowa (LME) sur les plans hydrologique, morphométrique et physicochimique, une étude a été menée de février à juillet 2012. L’échantillonnage s’est fait à une fréquence bimensuelle, entre la surface et 0.5 m de profondeur au niveau de trois points: S1 situé à quelques mètres de l’entrée des eaux de la rivière Mfoumou dans le LME, S2 situé au centre du LME à quelques mètres de son exutoire et S3 situé à quelques mètres de l’entrée des eaux de la rivière Bengo’o. Ces échantillons prélevés dans des bouteilles en plastique, sont transportés au laboratoire et analysés suivant des techniques appropriées. Les résultats obtenus mettent en évidence une diminution de la profondeur et de la superficie du LME, un débit spécifique moyen de 0,28 m3/s, une transparence n’excédant pas les 50 cm et un temps de renouvellement des eaux largement inférieur à une année. Ces résultats montrent que le LME se dégrade au fil des années, et se trouve au stade actuel d’hypereutrophie, conséquence de l’absence d’une politique de restauration développée et mise en œuvre par les autorités de la ville. En effet, aucune disposition particulière n’a été prise par les autorités en charge de la gestion du LME, pour y empêcher le déversement des déchets provenant à la fois du Marché Central, et des différentes structures qui le jouxtent. Au contraire, on assiste à Ebolowa à une augmentation des activités génératrices de déchets contribuant à aggraver la dégradation de ce lac. Cette situation laisse présager qu’à terme, on pourrait assister à une disparition totale de ce lac, ce qui ne serait pas nouveau car, des lacs de ce type ont déjà connu le même sort dans d’autres villes camerounaises (Bertoua et Yaoundé).Mots-clés : pollution, qualité des eaux, hypereutrophe, lac municipal d’Ebolowa.Hydrological, morphometrical and hydrochemical characterization of an urban hydrosystem: the Ebolowa municipal lake (South-Cameroon)Humanity is facing an important environmental problem, the degradation of surface waters quality, characterized by the asphyxia of aquatic ecosystems, as a result of the uncontrolled proliferation of algae that consume all oxygen necessary for the life of these ecosystems. In Cameroon many sources of water pollution have been identified but, the lack of a clearly defined wastes management strategy is the major reason of surface waters quality degradation. In order to evaluate the Ebolowa Municipal Lake (EML), hydrological, morphometrical and physicochemical parameters were studied from February to July 2012. Samples was collected twice a month, between the surface and 0.5 m depth at three sampling points : S1 located at few meters of the entrance of Mfoumou river waters; S2 located in the center of EML a few meters from its outlet and S3 located at few meters of the entrance of Bengo'o river waters in EML. Those samples were collected in plastic bottles, transported to the laboratory and analyzed with appropriate techniques. It appears from the results that the EML depth and area are continuously decreasing. The average specific flow is 0.28 m3/s, transparency is not exceeding 50 cm and the waters renewal time is below one year. According to these results, the quality of EML water is getting more and more degraded, and is currently in a hyper-eutrophic stage as a result of the absence of a restoration policy developed and implemented by Ebolowa city authorities. Unfortunately, No specific decisions have been taken by those authorities in order to prevent the discharge of wastes coming both from the Central Market and different structures situated around the lake. Instead, increase of waste generating activities in Ebolowa is contributing to the degradation of the lake. This suggests that there could be a total disappearance of the lake in the future, a situation which has been noticed in others lakes located in Cameroonian cities (Bertoua and Yaounde).Keywords : pollution, water quality, hyper-eutrophic, Ebolowa municipal lake

Revision Endoscopic Gastroplasty: An Overview and Review of Literature

The main aim of this paper was to examine the efficacy and safety of revision endoscopic gastroplasty and some of the adverse events likely to arise from the procedure, as well as the implications for future scholarly research. The study is a systematic review in which the PRISMA protocol was used to govern the article\u27s inclusion and exclusion criteria. The selected studies include those on revising endoscopic gastroplasty\u27s effectiveness and safety. The studies were selected based on multiple parameters. The outcome included weight recidivism, excessive BMI loss, and absolute, total, or percentage weight loss. The outcome of this review confirmed that revision endoscopic gastroplasty is effective and safe. Mainly, revision endoscopic gastroplasty (R-EG) was found to counter-weight recidivism, especially short-term and mid-term. However, there is a need for additional scholarly investigations that would last several years to decades to inform the long-term efficacy of R-EG with precision