Legume Nitrogen Fixation and Symbioses in Low-Inputs Rainfed Rice Rotations

Cropping systems with legumes play key roles in farming systems in sub-Saharan Africa. However, how commonly legume associations perform in low input-systems is not well-known. Here, we studied four legume species used in three systems in rotation with upland rice, i.e., groundnut monocropping, sorghum–cowpea intercropping, and velvet bean–crotalaria intercropping, in two fertilization managements on the previous rice, i.e., manure alone or complemented with mineral fertilization. Legume suitability was assessed using rhizobial and mycorrhizal colonization rates, plant biomass production, shoot N and P content, and biological N2 fixation based on their δ15N natural abundance. Shoot and root biomasses varied significantly between legume species and were positively correlated with nodule number (r = 0.49 and 0.74, p-value < 0.05 and <0.001, respectively) and the amount of fixed N (r = 0.73 and 0.50, p-value < 0.001 and <0.05, respectively). The proportion of plant N derived from N2 fixation also varied significantly between species, with a higher percentage for velvet bean (66%), compared to the other three species (50 to 60%). Legume roots were weakly colonized by AM fungi, with similar levels between species. Overall, fertilization management did not significantly impact legume biomass, symbioses, or N2 fixation, yet the organo-mineral fertilization significantly increased legume shoot P content. The lack of effect of mineral fertilization on N2 fixation and biomass could be due to other nutrient deficiencies (Ca, Mg, micronutrients), which can hamper symbioses with rhizobia and mycorrhizae.

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Adolescent, Pregnant, and HIV-Infected: Risk of Adverse Pregnancy and Perinatal Outcomes in Young Women from Southern Mozambique

Journal of Clinical Medicine ◽

10.3390/jcm10081564 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1564

Author(s):

Clara Pons-Duran ◽

Aina Casellas ◽

Azucena Bardají ◽

Anifa Valá ◽

Esperança Sevene ◽

...

Keyword(s):

Hiv Infection ◽

Maternal Morbidity ◽

Low Birthweight ◽

Negative Binomial ◽

Perinatal Outcomes ◽

Sub Saharan Africa ◽

P Value ◽

Increased Risk ◽

Adverse Pregnancy ◽

The Impact

Sub-Saharan Africa concentrates the burden of HIV and the highest adolescent fertility rates. However, there is limited information about the impact of the interaction between adolescence and HIV infection on maternal health in the region. Data collected prospectively from three clinical trials conducted between 2003 and 2014 were analysed to evaluate the association between age, HIV infection, and their interaction, with the risk of maternal morbidity and adverse pregnancy and perinatal outcomes in women from southern Mozambique. Logistic regression and negative binomial models were used. A total of 2352 women were included in the analyses; 31% were adolescents (≤19 years) and 29% HIV-infected women. The effect of age on maternal morbidity and pregnancy and perinatal adverse outcomes was not modified by HIV status. Adolescence was associated with an increased incidence of hospital admissions (IRR 0.55, 95%CI 0.37–0.80 for women 20–24 years; IRR 0.60, 95%CI 0.42–0.85 for women >25 years compared to adolescents; p-value < 0.01) and outpatient visits (IRR 0.86, 95%CI 0.71–1.04; IRR 0.76, 95%CI 0.63–0.92; p-value = 0.02), and an increased likelihood of having a small-for-gestational age newborn (OR 0.50, 95%CI 0.38–0.65; OR 0.43, 95%CI 0.34–0.56; p-value < 0.001), a low birthweight (OR 0.40, 95%CI 0.27–0.59; OR 0.37, 95%CI 0.26–0.53; p-value <0.001) and a premature birth (OR 0.42, 95%CI 0.24–0.72; OR 0.51, 95%CI 0.32–0.82; p-value < 0.01). Adolescence was associated with an increased risk of poor morbidity, pregnancy and perinatal outcomes, irrespective of HIV infection. In addition to provision of a specific maternity care package for this vulnerable group interventions are imperative to prevent adolescent pregnancy.

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The impact of antenatal care on under‐five mortality in Ethiopia: a difference‐in‐differences analysis

BMC Pregnancy and Childbirth ◽

10.1186/s12884-020-03531-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Samuel Oduse ◽

Temesgen Zewotir ◽

Delia North

Keyword(s):

Antenatal Care ◽

Child Survival ◽

First Trimester ◽

Sub Saharan Africa ◽

P Value ◽

Difference In Differences ◽

Under Five ◽

Care Services ◽

Sub Saharan ◽

The Impact

Abstract Background Sub-Saharan Africa, as opposed to other regions, has the highest under-five mortality rates yet makes the least improvement in reducing under-five mortality. Despite the decline, Ethiopia is among the top ten countries contributing the most to global under-five mortalities. This article examines the impact of the number of antenatal care and the timing of first antenatal care on child health outcomes. We specifically investigated if the utilization of antenatal care services positively affects the reduction of under-five mortality. Methods We employ a difference-in-differences design with propensity score matching to identify direct causal effects of antenatal care on under-five mortality based on the Ethiopian Demographic Health Survey data of 2011 and 2016. Our sample includes 22 295 women between the ages of 14–49 who had antenatal care visits at different times before delivery. Results The study revealed 1 481 cases of reported under-five mortality. 99.0% of that under-five mortality cases are women who had less than eight antenatal care visits, while only 1% of that is by women who had eight or more antenatal care visits. Antenatal care visit decreases the likelihood of under-five mortality in Ethiopia by 45.2% (CI = 19.2–71.3%, P-value < 0.001) while the timing of first antenatal care within the first trimester decreases the likelihood of under-five mortality by 10% (CI = 5.7–15.6%, P-value < 0.001). Conclusions To achieve a significant reduction in the under-five mortality rate, Intervention programs that encourages more antenatal care visits should be considered. This will improve child survival and help in attaining Sustainable Development Goal targets.

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Production of cabbage grown in pots containing legumes' root and shoot

Revista CERES ◽

10.1590/s0034-737x2012000500015 ◽

2012 ◽

Vol 59 (5) ◽

pp. 689-694 ◽

Cited By ~ 1

Author(s):

Thiago de Oliveira Vargas ◽

Ellen Rúbia Diniz ◽

Ricardo Henrique Silva Santos ◽

Alysson Roberto de Almeida ◽

Segundo Urquiaga ◽

...

Keyword(s):

Block Design ◽

Mineral Fertilizer ◽

Dry Weight ◽

N Fertilization ◽

Recommended Dose ◽

Legume Species ◽

Mineral Fertilization ◽

Mineral N ◽

Plant Parts ◽

Whole Plant

Roots effect is not generally considered in studies assessing the performance of crops in response to green manuring. However, such effect can contribute to a better understanding of crop rotation. The aim of this study was to assess the effect of root and shoot of two legumes on the production of cabbage. The experiment was conducted in pots of 10 liters containing substrate of 2:1 soil/sand. The experiment was arranged in a factorial scheme (2x3 + 2) in a randomized block design with five replicates using two legume species (Crotalaria juncea L. and Canavalia ensiformis L), three plant parts (root, shoot, or whole plant), and two additional treatments (mineral fertilization with 100% and 50% of the recommended dose of N for growing cabbage). Pots with legume treatments received mineral fertilizer with 50% of the recommended dose of N for growing cabbage. The experimental plot consisted of a pot containing one plant of cabbage. Legumes were grown in pots and harvested at 78 days. The root biomass was determined in extra pots. Production was assessed using head fresh and dry weight. The application of the whole plant of both legume species reduced cabbage production. However, root or shoot of both legume species was equivalent to 50% of mineral N fertilization required for the cultivation of cabbage.

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Dynamics of Intercepted Solar Radiation to Simulate Dry Matter of Soybean (Glycine Max (L.) Merrill)

Agromet ◽

10.29244/j.agromet.31.1.43-52 ◽

2017 ◽

Vol 31 (1) ◽

pp. 43

Author(s):

Pono Ngatui ◽

. Handoko ◽

Bregas Budianto ◽

Marliana Tri Widyastuti

Keyword(s):

Glycine Max ◽

Solar Radiation ◽

Dry Matter ◽

Plant Biomass ◽

P Value ◽

Modeling Experiment ◽

Glycine Max L ◽

Generative Phase ◽

Intercepted Solar Radiation ◽

Intercepted Radiation

Solar radiation greatly affects the development of plant biomass. The process of plant development is complex. Here, we simplified this complexity through modeling experiment by integrating climate variables. This study aims to determine the dynamics of canopy intercepted solar radiation under soybean (Glycine Max (L.) Merrill). We employed the shierary-rice model to calculate plant biomass. The results showed that intercepted radiation continuosly increased during vegetative phase, whereas the radiation remains constant during generative phase. Our observation confirmed that the pattern of intercepted radiation followed the angular pattern of sunlight. The intercepted radiation was optimum at 10:00 to 14:00 pm, and it was used to form the plant dry matter. We found that the intercepted radiation contributed until 12%. Based on this contribution, we built our crop model of soybean biomass. Our model performed well in simulating dry biomass with high R2 (0.9), and as indicated by the plot 1:1 between dry matter of model and field observations. Further, the result of t test between model and observed data confirm this strong corelation (p-value 0.07).

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Water Response of Upland Rice Varieties Adopted in Sub-Saharan Africa: A Water Application Experiment

Rice Research Open Access ◽

10.4172/jrr.1000121 ◽

2014 ◽

Vol 2 (1) ◽

Cited By ~ 2

Author(s):

Shunsuke Matsumoto ◽

Tatsushi Tsuboi

Keyword(s):

Upland Rice ◽

Sub Saharan Africa ◽

Water Application ◽

Rice Varieties ◽

Sub Saharan ◽

Water Response

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Diversity and Abundance of Potential Vectors of Rift Valley Fever Virus in the North Region of Cameroon

Insects ◽

10.3390/insects11110814 ◽

2020 ◽

Vol 11 (11) ◽

pp. 814

Author(s):

Poueme Namegni Rodrigue Simonet ◽

Njan-Nloga Alexandre Michel ◽

Wade Abel ◽

Eisenbarth Albert ◽

Groschup Martin Hermann ◽

...

Keyword(s):

Rift Valley ◽

Rift Valley Fever ◽

Rift Valley Fever Virus ◽

Fever Virus ◽

Control Measures ◽

Sub Saharan Africa ◽

Effective Control ◽

P Value ◽

Valley Fever ◽

The North

Rift Valley fever (RVF) is a major viral zoonosis transmitted by mosquitoes. The virus is endemic in most parts of sub-Saharan Africa and can affect humans, livestock, and wild ungulates. Knowledge of the biology of vectors of Rift Valley fever virus (RVFV) is essential for the establishment of effective control measures of the disease. The objective of this study was to determine the species diversity and relative abundance of potential RVFV vectors in the North Region of Cameroon. Adult mosquitoes were trapped during the wet and dry seasons from December 2017 to January 2019 with “EVS Light” traps with CO2 baits placed at selected sites. The captured mosquitoes were identified using dichotomous keys according to standard procedures. The abundance was calculated with regard to site, zone, and collection season. A total of 27,851 mosquitoes belonging to four genera (Aedes, Anopheles, Mansonia, and Culex) and comprising 31 species were caught (including 22 secondary vectors (98.05%) and nine primary vectors (1.94%). The total number of mosquitoes varied significantly depending on the locality (p-value < 0.001). The average number of mosquitoes collected per trap night was significantly higher in irrigated areas (p-value < 0.001), compared to urban and non-irrigated areas. The study revealed the presence of potential primary and secondary vectors of RVFV with varying abundance and diversity according to locality and ecological site in the North Region of Cameroon. The results showed that the genus Mansonia with the species Ma. uniformis and Ma. africana formed the dominant taxon (52.33%), followed by the genera Culex (45.04%) and Anopheles (2.61%). The need for molecular analysis (PCR) tests for RVFV RNA research and viral isolation methods on these vectors to determine their role in the epidemiology and control of RVF cannot be overemphasized.

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Sorghum–Insect Composites for Healthier Cookies: Nutritional, Functional, and Technological Evaluation

Foods ◽

10.3390/foods9101427 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1427

Author(s):

Temitope D. Awobusuyi ◽

Muthulisi Siwela ◽

Kirthee Pillay

Keyword(s):

Wheat Flour ◽

Protein Energy Malnutrition ◽

Sub Saharan Africa ◽

Health Concern ◽

Nutrient Deficiencies ◽

Substitution Level ◽

Protein Energy ◽

Nutritional Qualities ◽

Sub Saharan ◽

Spread Factor

Protein-energy malnutrition (PEM) is a major health concern in sub-Saharan Africa (SSA). Relying on unexploited and regionally available rich sources of proteins such as insects and sorghum might contribute towards addressing PEM among at-risk populations. Insects are high in nutrients, especially protein, and are abundant in SSA. Sorghum is adapted to the tropical areas of SSA and as such it is an appropriate source of energy compared with temperate cereals like wheat. It is necessary to assess whether cookies fortified with sorghum and termite would be suitable for use in addressing PEM in SSA. Whole grain sorghum meal and termite meal were mixed at a 3:1 ratio (w/w sorghum:termite) to form a sorghum–termite meal blend. Composite cookies were prepared where the sorghum–termite blend partially substituted wheat flour at 20%, 40%, and 60% (sorghum–termite blend:wheat flour (w/w). The functional and nutritional qualities of the cookies were assessed. Compared with the control (100% wheat flour), the cookies fortified with sorghum and termite had about double the quantity of protein, minerals, and amino acids. However, with increased substitution level of the sorghum–termite blend, the spread factor of the cookies decreased. There is a potential to incorporate sorghum and termite in cookies for increased intake of several nutrients by communities that are vulnerable to nutrient deficiencies, especially PEM.

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Soil phosphorus depletion capacity of arbuscular mycorrhizae formed by maize hybrids

Canadian Journal of Soil Science ◽

10.4141/s02-037 ◽

2003 ◽

Vol 83 (4) ◽

pp. 337-342 ◽

Cited By ~ 6

Author(s):

A. Liu ◽

C. Hamel ◽

S. H. Begna ◽

B. L. Ma ◽

D. L. Smith

Keyword(s):

Plant Biomass ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

P Uptake ◽

Maize Hybrids ◽

Soil P ◽

Extractable P ◽

P Content ◽

Total P ◽

Extractable Soil

The ability of arbuscular mycorrhizal (AM) fungi to help their host plant absorb soil P is well known, but little attention has been paid to the effect of AM fungi on soil P depletion capacity. A greenhouse experiment was conducted to assess, under different P levels, the effects of mycorrhizae on extractable soil P and P uptake by maize hybrids with contrasting phenotypes. The experiment had three factors, including two mycorrhizal treatments (mycorrhizal and non-mycorrhizal), three P fertilizer rates (0, 40, and 80 mg kg-1) and three maize hybrids [leafy normal stature (LNS), leafy reduced stature (LRS) and a conventional hybrid, Pioneer 3979 (P3979)]. Extractable soil P was determined after 3, 6 and 9 wk of maize growth. Plant biomass, P concentration and total P content were also determined after 9 wk of growth. Fertilization increased soil extractable P, plant biomass, P concentration in plants and total P uptake. In contrast to P3979, the LNS and LRS hybrids had higher biomass and total P content when mycorrhizal. Mycorrhizae had less influence on soil extractable P than on total P uptake by plants. The absence of P fertilization increased the importance of AM fungi for P uptake, which markedly reduced soil extractable P under AM plants during growth. This effect was strongest for LNS, the most mycorrhizae-dependent hybrid, intermediate for LRS, and not significant for the commercial hybrid P3979, which did not respond to AM inoculation. Key words: Arbuscular mycorrhizal fungi, extraradical hyphae, maize hybrid,plant biomass, P uptake, soil extractable P

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Seedling treatments and phosphorus solution concentrations affect nodulation and nodule functions in soybean (Glycine max L.)

Plant Soil and Environment ◽

10.17221/2301-pse ◽

2008 ◽

Vol 53 (No. 2) ◽

pp. 65-71 ◽

Cited By ~ 2

Author(s):

S.J. Miao ◽

X.Z. Han ◽

X.B. Liu ◽

Y.F. Qiao

Keyword(s):

Glycine Max ◽

Plant Biomass ◽

Dry Weight ◽

Solution Culture ◽

Acetylene Reduction Activity ◽

Nodule Size ◽

Reduction Activity ◽

P Content ◽

Significant Difference ◽

Nutrient Solution Culture

The effect of three seedling treatments: T0, normal germination; T1, cotyledons removed; T2, cotyledons removed 5 days earlier than in T1; and two phosphorus levels (P0 and P30) on nodulation and nodule function in soybean [Glycine max (L.) Merr.] were investigated in nutrient solution culture. The number of nodules formed at P0 was in the order T2 > T0 > T1, but it was T0 > T2 > T1 at P30. Nodule dry weight per plant had the same tendency as the nodule number. Nodule size (dry weight per nodule) in seedlings ranged from 0.601 to 1.089 mg in the order T0 > T1 > T2, regardless of P level. For example, nodule size in T0 was larger by 86% and 52% than T2 at P0 and P30, respectively. Furthermore, regardless of P level, a specific acetylene reduction activity (ARA, µM C2H4/h/g nodule) increased with P content in seedlings, but no significant difference was found (P < 0.05). Leghemoglobin (Lb) content was not significantly affected by P level; however, seedlings (T0 and T1) significantly affected the Lb content per unit plant biomass (P < 0.05). All these results suggest that seedling P content plays a key role in nodulation and nodule function of soybean.

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PO 8271 PFHRP2 GENE DELETIONS IN PLASMODIUM FALCIPARUM AND SCHISTOSOMA MANSONI CO-INFECTIONS: AN EMERGING CHALLENGE FOR MALARIA RAPID DIAGNOSTIC TESTS

BMJ Global Health ◽

10.1136/bmjgh-2019-edc.64 ◽

2019 ◽

Vol 4 (Suppl 3) ◽

pp. A25.2-A25

Author(s):

Hilda Echelibe ◽

Masumbe Netongo Palmer ◽

Nji Akindeh ◽

Wilfred Mbacham

Keyword(s):

Plasmodium Falciparum ◽

Schistosoma Mansoni ◽

Diagnostic Tests ◽

False Negative ◽

Rapid Diagnostic Tests ◽

Sub Saharan Africa ◽

P Value ◽

Gene Deletions ◽

Malaria Rdts ◽

Malaria Rapid Diagnostic Tests

BackgroundMalaria and schistosomiasis are infections that have a great impact in sub-Saharan Africa based on their high morbidity and mortality rates. We suggest the possibility that the microenvironment created from interactions between the parasites involved generates a pressure on the malaria parasite which could in turn favour the parasite’s adaptation or escape through Pfhrp2 gene deletions. Thus, this study aimed at determining the association between the co-infection with both parasites and false-negative PfHRP2-based malaria rapid diagnostic tests which occur because of these deletions.MethodsThis pilot study was conducted in a total of 149 children aged 7–17 years living in Yorro, located in the Mbam-Inoubou division of the Center region of Cameroon. We collected fresh stool samples from each participant to identify Schistosoma mansoni (Sm) eggs by Kato Katz method and blood samples to identify the ring stages of Plasmodium falciparum (Pf) by thick smear. Malaria rapid diagnostic test and Pfhrp2 gene polymerase chain reaction were performed. The association between the co-infection with Sm/Pf and the false-negative malaria RDTs was determined by the Fisher’s exact test. A p value<0.05 was considered statistically significant.ResultsOur results showed that samples were singly infected with Sm, Pf, co-infected (Sm/Pf) and negative for both infections at frequencies of 12%, 43%, 30.2% and 14.8% respectively. False-negative PfHRP2-based RDTs were observed in 4.7% of the participants. A higher frequency (5/7) of the cases with false-negative malaria RDTs were co-infected with Sm/Pf. A p value of 0.027 showed statistical significance in the association of Sm/Pf co-infection and false-negative PfHRP2-based RDTs.ConclusionA significant association of Plasmodium falciparum and Schistosoma mansoni co-infection with false-negative PfHRP2-based RDTs supports the case for a plausible implication of Pfhrp2 gene deletions, with consequences for malaria rapid diagnostic testing.

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