Baboucarr Manneh

• PhD
• AfricaRice Regional Representative Senegal & Rice Breeder at Africa Rice Center (Africarice)

Arbuscular mycorrhizal fungi (AMF) enhance the uptake of water and nutrients by host plants. In this study, we examined the response of six rice varieties from two ecotypes (three irrigated and three rainfed upland varieties) to AMF inoculation at five fertilizer levels, under continuous flooding (CF) and alternate wetting and drying (AWD) irrigati...

Introduction Long-term fertilization affects bacterial, archaeal and fungal communities composition Soil microorganisms play a major role in maintaining soil health and productivity. Here, we examined the impact of two long-term fertility experiments (LTFE) carried out over a period of 25 years on soil microbial community in intensive rice-based ir...

Context Soil salinity is one of the major constraints to irrigated rice production in the Senegal River Valley. Several technologies such as salt-tolerant varieties and improved nutrient management practices have been evaluated. However, their on-farm performance is not well known. Objective The objective of this study was to assess the agronomic a...

In Senegal, the average rice consumed is 100 kg per capita per year. The objective was to evaluate and select the well‐adapted high‐yielding lines in Ndiaye and Fanaye growth conditions in Senegal River Valley. One hundred and twelve advanced lines were evaluated in consecutive wet and dry seasons at AfricaRice Fanaye and Ndiaye sites challenged by...

To evaluate the varietal stability of rice grown under irrigated conditions, trials were conducted on thirty-four rice varieties across two locations. The objective of this study was to examine the impact of genotype × environment interactions (GEI) on high-yielding rice varieties. The primary focus was on the attributes of the rice varieties and t...

Rice (Oryza sativa L) is one of the most important staple food worldwide with a global production estimated at around 800 million metric tons for paddy rice in 2021. However, this production is hampered by several factors, such as land salinity. In this study, 230 F2:3 lines of the Sahel 328/NERICA-L-9 mapping populations were evaluated for their t...

Arbuscular mycorrhizal fungi (AMF) provide host plants with water and nutrients. Here, we investigated the response of six rice varieties from two ecotypes (three irrigated and three rainfed upland varieties) to inoculation at five fertilizer levels, under continuous flooding (CF) and alternate wetting and drying (AWD) irrigation in field condition...

Rice is an important cereal crop in many countries, but its production in the Senegal River Valley is hampered by adverse climatic conditions. This study was aimed at evaluating the diversity among genotypes and the association between several phenological and yield attributes of irrigated rice to mitigate the consequences of climate change. During...

Rice is an important cereal crop in many countries, but its production in the Senegal River Valley is hampered by adverse climatic conditions. This study was aimed at evaluating the diversity among genotypes and the association between several phenological and yield attributes of irrigated rice to mitigate the consequences of climate change. During...

Background Rhizosphere microbial communities are important components of the soil-plant continuum in paddy field ecosystems. These rhizosphere communities contribute to nutrient cycling and rice productivity. The use of fertilizers is a common agricultural practice in rice paddy fields. However, the long-term impact of the fertilizers usage on the...

Rhizosphere microbial communities are important components of the soil-plant-atmosphere continuum in paddy field ecosystems where they contribute to nutrient cycling and rice productivity. However, the rhizosphere microbial sensitivity to anthropic soil disturbance across plant growth stages remains little investigated. Here, we tracked the effects...

Improving crop water use efficiency, the amount of carbon assimilated as biomass per unit of water used by a plant, is of major importance as water for agriculture becomes scarcer. In rice, the genetic bases of transpiration efficiency, the derivation of water use efficiency at the whole-plant scale, and its putative component trait transpiration r...

Because water availability is the most important environmental factor limiting crop production, improving water use efficiency, the amount of carbon fixed per water used, is a major target for crop improvement. In rice, the genetic bases of transpiration efficiency, the derivation of water use efficiency at the whole-plant scale, and its putative c...

Genetic improvement has been given high priority in rice research for development in sub-Saharan Africa (SSA). This paper provides an overview of historical efforts of genetic improvement in SSA focused on improving rice productivity. It further describes yield gain of new rice varieties evaluated in recent field experiments in four selected breedi...

Salt stress is a menace to rice production and a threat to food security worldwide. We evaluated 308 F 4 families from Sahel 317/Madina Koyo for tolerance to salt stress at the early seedling stage. To better understand genomic regions controlling tolerance in the population, we genotyped the progenies and the two parents using single nucleotide po...

Soil salinity is a threat to crop production in the Senegal River Delta where salt intrusion increases soil electrical conductivity and most of farmers had abandoned their rice farms. The objective of this study was to evaluate an integrated management to improve rice productivity under saline soil condition in the Senegal River Delta. Field experi...

Estimation of yield reduction in crop caused by the salinity stress is mostly based on variations of soil electrical conductivity and the severity of water stress. Crop response curves to salinity were developed without considering ion toxicity and nutritional imbalance in the plant. The objective of this study was to explore the possibility of usi...

Growing rice in saline soils by minimizing damage on growth and yield remains a challenge. We conducted field experiments in the Africa Rice research field located in the Senegal River delta (16° 11’ N, 16° 15’ W) to study the effects of three management options of fertilization e.g. (i) nitrogen, phosphorus, and potassium fertilization: NPK; (ii)...

The adoption of the Penman-Monteith reference evapotranspiration (ETo) method necessitates the use of climatic data and parameters measured above a reference surface (e.g., reference grass), which is rarely available across agro-ecosystems in all countries. In such cases, alternatively, climate data collected above other vegetation surfaces can be...

Crop inoculation with beneficial soil microbes has been proposed as an sustainable alternative to agro-chemicals. However, use of inoculation requires selecting optimal combinations of crop varieties and associated microbes to increase the efficiency of production systems. We previously showed that rice response to microbial inoculation was depende...

Good agreement between climatic parameters measured above rice and grass canopies. The good fit between the ETo values from data measured and estimated above both canopies demonstrates the possibility of using climatic data measured above flooded rice canopy to compute ETo as an appropriate alternative when the climate data from reference weather...

Rice is one of the most consumed crop around the globe and its production needs to be increased in a context of climate change and water scarcity. Rice roots, as most land plants, can establish symbiotic association with arbuscular mycorrhizal fungi (AMF). Rice has emerged, in the past decade, as a model to study the molecular determinants of AM sy...

Rice genotypes showed different response to the AWD with significant synergistic irrigation regime and nitrogen rates interaction AWD30 contributed to reduction in irrigation events by 27.3% The AWD30 under the 150 kg N/ha helped achieving an increase in rice yield of 18.2 and 6%, increase in NUE of 30.6 and 8.4% AWD30 kPa is a safe AWD that ca...

The objectives of this study were to investigate water saving strategies in the paddy field and to evaluate the performance of some of the newly released rice varieties. Field experiments were conducted at Fanaye in the Senegal River Valley during two rice growing seasons in 2015. Three irrigation regimes ((i) continuous flooding, (ii) trigging irr...

Using interspecific crosses involving Oryza glaberrima Steud. as donor and O. sativa L. as recurrent parents, rice breeders at the Africa Rice Center developed several ‘New Rice for Africa (NERICA)’ improved varieties. A smaller number of interspecific and intraspecific varieties have also been released as ‘Advanced Rice for Africa (ARICA)’. The ob...

The current study was to understand the genes action in salt tolerance of rice and its use in the future breeding program. The research was carried out in Niger Republic. 120 F3 lines derived from F2 individual plants were evaluated along with their parents in farmer’s field affected by the salt problem. The experimental design was 25*5 Alpha latti...

Markers assisted selection is a tool for improving the speed and efficiency of crop improvement. The identification of SNPs within the target genomic region of a QTL is necessary for efficient breeding of quantitative traits such as salt tolerance. The study was conducted to characterize parental lines using SNP markers and to identify the polymorp...

Markers assisted selection is a tool for improving the speed and efficiency of crop improvement. The identification of SNPs within the target genomic region of a QTL is necessary for efficient breeding of quantitative traits such as salt tolerance. The study was conducted to characterize parental lines using SNP markers and to identify the polymorp...

Increase grain yield potential is one of the most important objectives of any cereal crop breeding program. To efficiently develop superior rice lines by the introgression of favorable alleles for yield and yield component traits, a strategy of alternate phenotype–genotype selection was used. The present study aimed to (i) investigate the allelic d...

Rice is one of the most important crops in the world. Salinity is a major problem limiting rice production in West Africa and the most serious abiotic constraint in Niger. It causes drastic yield losses and hence loss of income for rice farmers. Improvement of salt stress tolerance in rice varieties would increase grain yield of rice under slight s...

Phenology and time of flowering are crucial determinants of rice adaptation to climate variation. A previous study characterized flowering responses of 203 diverse indica rices (the ORYTAGE panel) to ten environments in Senegal (six sowing dates) and Madagascar (two years and two altitudes) under irrigation in the field. This study used the physiol...

Low night and high day temperatures during sensitive reproductive stages cause spikelet sterility in rice. Phenotyping of tolerance traits in the field is difficult because of temporal interactions with phenology and organ temperature differing from ambient. Physiological models can be used to separate these effects. A 203-accession indica rice div...

Rice is a staple food in West Africa, where its demand keeps increasing due to population growth. Hence, there is an urgent need to identify high yielding rice cultivars that fulfill this demand locally. Rice hybrids are already known to significantly increase productivity. This study evaluated the potential of Asian hybrids with good adaptability...

The objectives of this study were to investigate water saving strategies in the paddy field and to evaluate the performance of some of the newly released rice varieties. Field experiments were conducted at Fanaye in the Senegal River Valley during two rice growing seasons in 2015. Three irrigation regimes [(i) continuous flooding, (ii) trigging irr...

The overuse of agricultural chemicals such as fertilizer and pesticides aimed at increasing crop yield results in environmental damage, particularly in the Sahelian zone where soils are fragile. Crop inoculation with beneficial soil microbes appears as a good alternative for reducing agricultural chemical needs, especially for small farmers. This,...

Root length and frequency of colonization of inoculated plants of O. sativa var. Sahel 202 for the 1st and 2nd-year trials. In each column, means followed by the same letter are not significantly different at P≤0.05. (PDF)

Height of non-inoculated and inoculated plants of O. sativa Sahel 202. A single microbial strain (AMF or PGPR, A), two strains (B), and 3 and 4 strains (C), were used in the 1st year (A1, B1 and C1) and 2nd year (A2, B2 and C2) trials. Ri: Rhizophagus irregularis; Ga: Glomus aggregatum; ORS 278: Bradyrhizobium sp. ORS 278; and ORS 3454: Leifsonia s...

Student’s t-test for the ln (x +10) transformed values of agronomic traits in rice plants at variety level. AM: inoculated with AMF and NM: non-inoculated. Abbreviations associated to the variety names indicate the rice ecotype (Upl: Upland, Irr: Irrigated, Rll: Rainfed lowland). (PDF)

ANOVA for the ln (x +10) transformed values of agronomic traits in rice plants at ecotype level. AMF inoculation (inoculated and non-inoculated), ecotype (upland, irrigated and rainfed lowland) and year (1st and 2nd-year trial). (PDF)

ANOVA for the ln (x +10) transformed values of agronomic traits in rice plants at variety level. AMF inoculation (inoculated and non-inoculated), variety (each of the 8 varieties tested) and year (1st and 2nd-year trial). (PDF)

Collar section growth curves of non-inoculated and inoculated plants of O. sativa Sahel 202. A single microbial strain (AMF or PGPR, D1 and D2), two strains (E1 and E2), and 3 and 4 strains (F1 and F2), were used in the 1st year (D1, E1 and F1) and 2nd year (D2, E2 and F2) trials. Ri: Rhizophagus irregularis; Ga: Glomus aggregatum; ORS 278: Bradyrh...

Student’s t-test for the ln (x +10) transformed values of agronomic traits in rice plants at ecotype level. AM: inoculated with AMF and NM: non-inoculated. (PDF)

Rice is the main crop produced in the Senegal River Valley under the semiarid sahelian climate where water resource management is critical for the resource use sustainability. However, very limited data exit on rice water use and irrigation water requirement in this water scarcity environment under climate change conditions. Understanding crop wate...

Feeding the future world population requires increased crop production. Here, we investigate the intensification option of increasing production by increasing cropping intensity and choice of varieties with different crop duration. We developed a model to generate, compare and visualise opportunities for single/double/triple cropping systems consis...

La production de riz au Sénégal fait face à des contraintes liées aux changements climatiques telles que le déficit hydrique. A cela s’ajoute la baisse de la fertilité des sols consécutive aux prélèvements de grandes quantités de nutriments des sols. Les effets isolés ou conjugués de ces contraintes limitent la productivité des écosystèmes rizicole...

DNA markers enabled to determine the chromosomal locations of the two Rf genes (Rf3 and Rf4) in the wild-abortive cytoplasmic male sterility (WA-CMS) system. Four simple sequence repeats (SSRs) RM171, RM258, RM315 and RM443 were used to detect the allelic status with respect to the fertility restoration genes (Rf3 and Rf4) in 300 rice cultivars or...

Salinity is a major abiotic constraint that retrains rice production worldwide. The development and release of rice cultivars with improved performance in saline environments is essential to fight against this scourge. Hence this study was carried out to evaluate segregating populations of rice in Niger where salinity is a major constraint. Thus 12...

In the Sahel zone of West Africa that extends from Senegal to Chad, temperatures can vary from less than 15 °C to 25 °C from November to February. These low temperatures affect the growth, development and yield of rice plants, and therefore constitute a major constraint to rice production in the Sahel. In order to identify rice varieties tolerant t...

In rainfed rice cultivation, weeds, low or no fertiliser inputs and no water control can be production constraints. Vegetative early vigor may favour weed competitiveness. Since Oryza glaberrima is considered as genetic resources for this characteristic, growth analyses of three lines were made from seeds to juvenile plants of 35 days after seed so...

Study region Reference evapotranspiration (ETo) plays a key role in irrigation systems design, water management under irrigated and rainfed production. Under the sahelian conditions in the Senegal River Valley that receives less than 300 mm annual rainfall, rice crop water use should be estimated for the sustainability of the resource. Study focus...

Rice production faces the challenge to be enhanced by 50% by year 2030 to meet the growth of the population in rice-eating countries. Whereas yield of cereal crops tend to reach plateaus and a yield is likely to be deeply affected by climate instability and resource scarcity in the coming decades, building rice cultivars harboring root systems that...

Salinity is a major constraint affecting rice productivity in rainfed and irrigated agro-ecosystems. Understanding salinity effects on rice production at the reproductive stage could improve adaptation for this trait. Identifying quantitative trait loci (QTLs) controlling adaptation to salinity may also accelerate breeding rice germplasm for enviro...

In lowland rice production, water-saving irrigation technologies have been developed, but it has rarely been considered that the absence of a ponded water layer could change the field's microclimate due to the different thermal characteristics of water compared to air. At a site in the Senegal River valley, canopy and soil temperature as well as te...

Yield reductions have been widely observed under water-saving irrigation in lowland rice. The yield gap has been related to decreases in the number of spikelets per panicle and decreased spikelet fertility. Since these yield components highly depend on the thermal environment of the meristem which is subjected to changes when a ponded water layer i...

Growth and grain yield reductions have been widely observed when traditionally flooded rice fields were subjected to water-saving irrigation measures, where a continuous floodwater layer is avoided. These observations led to the perception of rice being a plant extremely sensitive to water stress even when grown in soils where water is sufficiently...

Abstract Salinity is one of the most serious factors limiting the productivity of rice crops, with adverse effects on germination, plant vigor and crop yield. A population of 300 F5:6 recombinant inbred lines RILs), which was derived from a cross between IR29 indica sensitive to salinity, and Hasawi Saudi cultivar showing salt tolerance), was evalu...

Salinity is a major constraint affecting rice productivity in rainfed and irrigated agro-ecosystems. Understanding salinity effects on rice production at the reproductive stage could improve adaptation for this trait. Identifying quantitative trait loci (QTLs) controlling adaptation to salinity may also accelerate breeding rice germplasm for enviro...

This book provides a comprehensive overview of the rice sector in Africa and the ongoing rice research and development activities in the region. Specific topics are classified under the following headings: overview of rice in Africa (chapters 1-4), rice genetic diversity and improvement (chapters 5-14), sustainable productivity enhancement (chapter...

The study evaluated effects of drought on some agro-morphological traits of 60 rice genotypes comprising 54 introgression lines with their parents, IR 64 (Oryza sativa) and TOG 5681 (Oryza glaberrima) and four NERICA-L varieties developed from the same parents for comparison. The genotypes were subjected either to full irrigation from sowing to mat...

Africa Rice Center (AfricaRice) plays an important role in germplasm enhancement for their adaptation to different ecologies of upland, lowland, irrigated, mangrove and deep water. The genebank of AfricaRice contains over 20,000 rice accessions, notably two cultivated species (Oryza sativa and O. glaberrima) and wild species (O. longistaminata, O....

The ability to identify drought-resistant lines in all seasons would accelerate variety introduction. A total of 202 backcross-inbred lines of rice were subjected to drought during the 2006 and 2007 dry seasons at AfricaRice in Benin.Twoirrigation regimes were applied: fully irrigated to maturity and 21 days of drought from 45 days after sowing. Pl...

I n sub-Saharan Africa, rice is one of the most significant crops—as both a food and cash crop. This is evident from the recent civil unrest that broke out in many African countries because of rice shortages. As the African population is expected to hit one billion soon, the region is worried that its rice production will fall short of the growing...

Rice Improvement in the Genomics Era. Edited by DataS. K.. Boca RatonFl, USA: CRC Press/Taylor and Francis Group (2008), pp. 481, US$169.95. ISBN 978-1-56022-952-0. - Volume 45 Issue 3 - Baboucarr Manneh

Use of DNA-based markers can accelerate cultivar development in variable cultivation environments since, in contrast to phenotype, DNA markers are environment-independent. In an effort to elucidate the genetic basis of genotype-by-environment interaction (G×E) for yield of rice (Oryza sativa L.), the associations between 139 AFLP markers and grain...

Climate change is already impacting negatively on Africa through extreme temperatures, frequent flooding and droughts and increased salinity of water supplies used for irrigation. Widespread poverty and high dependence on rainfed agriculture in Africa renders the continent more vulnerable to climate change-induced disasters than other regions of th...