23 research outputs found

    Molecular detection of establishment and geographical distribution of Brazilian isolates of Neozygites tanajoae, a fungus pathogenic to cassava green mite, in Benin (West Africa)

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    Article purchasedDiagnostic PCR with two specific primer pairs (NEOSSU and 8DDC) were used to monitor the establishment and geographical distribution of Brazilian isolates of Neozygites tanajoae Delalibera, Hajek and Humber (Entomophthorales: Neozygitaceae) released in Benin for the biological control of the cassava green mite, Mononychellus tanajoa (Bondar) (Acari: Tetranychidae). A total of 141 cassava fields were visited and samples of M. tanajoa suspected to be infected by N. tanajoae were collected in 60 fields distributed between the coastal Southern Forest Mosaic (SFM) and the Northern Guinea Savanna (NGS) zones of Benin, West Africa. Analysis of DNA samples of dead mites using the species specific NEOSSU primers revealed the presence of N. tanajoae in 46 fields. The second country specific pair of primers 8DDC revealed the presence of Brazilian isolates of N. tanajoae in 36 fields, representing 78.3% of fields positive for N. tanajoae. Brazilian isolates occurred from SFM to NGS zones in Benin, however, they were concentrated in fields located within former release zones (e.g. Department of Ouémé in the South and Borgou in the North). In contrast, the indigenous African isolates of N. tanajoae were evenly distributed in the sub-humid and humid savannah zones of the country. The mean infection rate of M. tanajoa with indigenous isolates of N. tanajoae was relatively low (5.3%) compared to Brazilian isolates (28%), indicating a higher biocontrol potential of the latter. This first post-release monitoring using PCR techniques showed that the Brazilian strains of N. tanajoae is well established in Benin and spread effectively in this area

    Interactions between the predatory mite Typhlodromalus aripo and the entomopathogenic fungus Neozygites tanajoae and consequences for the suppression of their shared prey/host Mononychellus tanajoa

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    Published online: 28 October 2012The predatory mite Typhlodromalus aripo and the entomopathogenic fungus Neozygites tanajoae, both introduced from Brazil for control of the cassava green mite (CGM) Mononychellus tanajoa, now co-occur in cassava fields in Benin. However, studies on interactions between these two natural enemies and how they might affect CGM biological control are lacking. We determined in screenhouse experiments the effects of single and combined releases of N. tanajoae and T. aripo on CGM suppression. In the single natural enemy treatment, both T. aripo and N. tanajoae significantly reduced CGM densities, but the results of the predator (T. aripo) are more quickly measurable than those of the pathogen (N. tanajoae) in our short-term experiment. The level of CGM suppression in the combined natural enemy treatment was reduced considerably compared with T. aripoalone, but only slightly when compared with N. tanajoae alone, with a simultaneous reduction in T. aripo and N. tanajoae abundance or prevalence. In a laboratory experiment, T. aripo fed more on N. tanajoae-infected CGM than on healthy CGM and its oviposition and survival were reduced when fed on the former compared with the latter, which can help in explaining the reduction in numbers of T. aripo and consequently the considerable loss in suppression of CGM in the combined natural enemy treatment in the screenhouse experiment. Together, the screenhouse and the laboratory experiments predicted negative interactions between the two natural enemies with negative consequences for CGM biological control. Long-term field observations and rigorous field experiments that simultaneously manipulate T. aripo and N. tanajoae abundance and prevalence are needed to validate the prediction of this study

    Farmers' perception of climate change and climate-smart agriculture in northern Benin, west Africa

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    Climate-Smart Agriculture (CSA) is an approach that identifies actions needed to transform and reorganize agricultural systems to effectively support agricultural development and ensure food security in the face of climate change. In this study, we assessed farmers’ perception of climate change, available CSA practices (CSAP) and the determinants of CSAP adoption in northern Benin. A list of CSAP was generated from a workshop with different stakeholders. Face-to-face interviews were then carried out with 368 farmers selected based on stratified random sampling in the study area. Binomial generalized mixed-effect models were run to analyze the relation between socio-demographic characteristics and the use of CSAP. CSAP were evaluated using a three-point Likert scale and the frequency of agreement with the statement that the selected practices meet the pillars of CSA. More than 60% of farmers had heard about climate change, and more than 80% had observed changes in temperature, rainfall amounts and distribution. Thirty-one CSAP were identified in the area, and only 11 were known by more than 50% of farmers. Out of the 12 selected CSAP for the assessment of adoption and evaluation, seven (7) were used by more than 50% of those who knew them. Farmers agreed with the statements that the evaluated practices improved farm productivity and adaptation to climate change but did not mitigate climate change. Ethnic group and education level were the two major factors that significantly determined the use of the evaluated CSAP

    Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa

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    Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest

    Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota)

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    Compared to the higher fungi (Dikarya), taxonomic and evolutionary studies on the basal clades of fungi are fewer in number. Thus, the generic boundaries and higher ranks in the basal clades of fungi are poorly known. Recent DNA based taxonomic studies have provided reliable and accurate information. It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines. Recently, Tedersoo et al. (MycoKeys 13:1--20, 2016) accepted Aphelidiomycota and Rozellomycota in Fungal clade. Thus, we regard both these phyla as members in Kingdom Fungi. We accept 16 phyla in basal clades viz. Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota. Thus, 611 genera in 153 families, 43 orders and 18 classes are provided with details of classification, synonyms, life modes, distribution, recent literature and genomic data. Moreover, Catenariaceae Couch is proposed to be conserved, Cladochytriales Mozl.-Standr. is emended and the family Nephridiophagaceae is introduced

    Analyse du debit de filtration glomerulaire de repos chez des joueuses de sports collectifs au Benin

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    L’homĂ©ostasie est rĂ©guliĂšrement perturbĂ©e chez l’athlĂšte dont la fonction rĂ©nale est de plus en plus explorĂ©e. La prĂ©sente Ă©tude vise Ă  apprĂ©cier au repos, les valeurs des paramĂštres rĂ©naux chez des pratiquantes de sports collectifs du BĂ©nin. Elle a Ă©tĂ© rĂ©alisĂ©e selon une approche transversale avec 62 basketteuses, footballeuses et handballeuses, chez qui la crĂ©atinine sĂ©rique, l’albumine plasmatique, les taux d’hĂ©moglobine et d’hĂ©matocrite, ainsi que le dĂ©bit de filtration glomĂ©rulaire estimĂ© (DFGe) avec trois diffĂ©rentes formules, ont Ă©tĂ© dĂ©terminĂ©s. Dans le groupe Ă©tudiĂ©, la valeur moyenne de la crĂ©atininĂ©mie est de 9,5 ± 1,2 mg/L. Le DFG moyen estimĂ© avec l’équation MDRD (74,2 ± 11,6 mL/min/1,73 m2) Ă©tait plus bas que celui estimĂ© avec la formule CGc (89,4 ± 13,0 mL/min/1,73 m2; p < 0,001) et celle du CKD-EPI Four-level race (99,7 ± 16,1 mL/min/1,73 m2, p < 0,001) malgrĂ© la forte corrĂ©lation observĂ©e entre les trois formules (r > 0,91; p < 0,001). Le taux d’hĂ©moglobine moyen Ă©tait de 11,3 ± 0,9 g/100 mL avec 75,8% (n = 47) des joueuses ayant un [Hb] < 12 g/100 mL. La valeur moyenne de l’albumine plasmatique Ă©tait de 45,2 ± 3,4 g/L. Le DFGe des filles Ă©tudiĂ©es a variĂ© en fonction des trois formules utilisĂ©es. MalgrĂ© les valeurs basses du DFGe enregistrĂ©es, la fonction rĂ©nale des joueuses peut ĂȘtre considĂ©rĂ©e comme normale. Les formules CGc et CKD-EPI Four-level race sont apparues comme les plus appropriĂ©es pour Ă©valuer la fonction glomĂ©rulaire chez les joueuses de sports collectifs du BĂ©nin.Mots clĂ©s: DFGe, femmes, sport collectif, climat subtropicalEnglish Title: Analysis of resting glomerular filtration rate of female team sports players in BeninEnglish AbstractHomeostasis is regularly disturbed in athlete’s whose renal function is increasingly explored. This study aims at assessing resting values of renal parameters of team sports players in the Republic of Benin.. It was a cross sectional study carried out in tranversal approach with 62 females basketball, football and handball players. Serum creatinin, plasma albumin, hemoglobin [Hb]and hematocrite [Hte] rates were assessed, and  estimated glomerular filtration [eGER] was estimated with rate with three different formulas. In the study group, the mean serum creatinine was 9.5 ± 1.2 mg/L.The mean eGFR with MDRD formula (74.2 ± 11.6 mL/min/1.73 m2) was lower than both that estimated with CGc formula (89.4 ± 13.0 mL/min/1.73 m2, p < 0.001) and that of CKDEPI Four-level race (99.7 ± 16.1 mL/min/1.73 m2, p < 0.001). A high strong correlation has been observed between the three formulas i. e. ≄ 0.91, (p < 0.001). The mean [Hb] hemoglobin and hematocrite were respectively 11.3 ± 0.9 g/100 mL and 33.4 ± 3.5%, with 75.8% of the players showing a [Hb] < 12 g/100 mL. The mean plasma albumin was 45.2 ± 3.4 g/L. The mean eGFR varied with the three formulas used. Despite the low values of eGFR recorded, the renal function of these female team sports players may be considered normal. The CGc and CKD-EPI Four-level race Formulas appeared as the most appropriate for assessing the glomerular function among team sports players in the Republic of Benin.Keywords: renal function, female, collective sports, subtropical clima

    Acute effects of a basketball match on urine protein/creatinine ratio in sub-elite women players in a sub-Saharan environment

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    Renal function is commonly evaluated by estimating glomerular filtration rate and proteinuria testing. A disturbance in the functioning of the kidneys may occur in top-level athletes during training and competition due to the associated high workloads and/or high water loss. This context requires the search for evaluation criteria more specific to athletes. In an effort to assess renal function during acute physical activity, this study evaluated the effects of a basketball match on urine protein/creatinine ratio (PCRurine) of women players in a sub-Saharan environment. An experimental study was conducted with 20 sub-elite female basketball players from the Republic of Benin. Urine proteins (UProt) and creatinine (UCrea), PCRurine and urine specific gravity (USG) were determined before, at the end and 24 hours after an experimental basketball match. Prior to the match, all players had normal values of each studied parameters, except for USG. UProt and UCrea increased by 64% (p = 0.0005) and 70% (p = 0.0006), respectively at the end of the match, but declined by 50% (p = 0.0001) and 51.5% (p = 0.0005), 24 hours later. The decrease in PCRurine during and 24 hours after the match was not significant (p ˃ 0.05). Under the study’s conditions, the basketball match induced transient proteinuria assessed by PCRurine in female sub-elite players. This non-invasive method could be used for frequent assessment of renal function in athletes with recourse to the invasive method if there was a strong suspicion of renal damage
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