Gabriel Mahbou Somo Toukam

Influence of organic and mycorrhizal fertilization on productivity and quality of strawberry ( Fragaria × ananassa Duch.) in sub-Saharan Africa

Alanis Cindy Noadje Kameni, Gabriel Mahbou Somo Toukam, Nono Carine Temegne, Laura Scottie Ngouana Tchinda, Herman Pascal Ewane Kounty, michael Fomekong Kenne et 5 autre(s)

European Journal of Horticultural Science

Abstract Introduction: A good fertilization practice is necessary to effectively improve the growth, yield and quality of Fragaria × ananassa Duch. in tropical areas. Materials and methods : This study proposed a fertilization approach for strawberry cultivation under poor soil conditions. The experimental design was a completely randomized block design with two factors: varieties (V1: Rubygem and V2: Charlotte) as the main factor and treatments (unfertilized control (T0), mineral fertilizer (T1), organic fertilizer (T2), mycorrhizae (T3) and the combination of organic fertilizer + mycorrhizae (T4)) as the secondary factor, with four repetitions. Results and discussion: The results show that the highest yield values were obtained with organic fertilizer treatments (46.24 ± 3.01 g/plant) in the Rubygem variety, while in the Charlotte variety, the combination of organic fertilizer + mycorrhizae (64.37 ± 4.79 g/plant) was more effective. Additionally, organic fertilizer applied alone and in combination with mycorrhizae proved to be the fertilizers that produced the highest numbers of runners in both varieties used (T2: 5 ± 1 and T4: 5 ± 0 for Rubygem; T2: 14.33 ± 2.52 and T4: 14 ± 2 for Charlotte). Regardless of the variety, organic fertilizer effectively increased phosphorus, potassium, magnesium and calcium contents. Furthermore, the response to mycorrhization was found to be variety-dependent. Indeed, in Rubygem, mycorrhizae significantly improved the protein content of the fruits and the content of pigments during flowering. In contrast, in Charlotte, it is rather the sugar and pigment contents during fruiting that have been significantly improved. Conclusion: Our findings suggest using organic fertilizer alone or in combination with mycorrhizae to improve strawberry production and quality. More investigations are required to assess this experiment under other conditions. Significance of this study What is already known on this subject? In Cameroon, strawberry cultivation is still on the rise and few strawberry growers use cultivation systems exclusively based on organic sources and fungi. It is known that organic fertilizers and mycorrhizae are important for producing organic strawberries to improve their growth, yield and quality. What are the new findings? Overall, organic fertilizers led to the highest mineral element content in the two strawberry varieties studied, as well as improved growth and yield parameters. The effects were similar, particularly in terms of growth and yield, with the application of organic fertilizer combined with mycorrhizae. However, except for the protein content in the Rubygem variety and the sugar content in the Charlotte variety, mycorrhizal fungi had a relatively minor influence on the parameters; the results were almost similar to those obtained with mineral fertilizer. What is the expected impact on horticulture? There is an expectation for the promotion of sustainable agricultural practices through the adoption of organic fertilizers, which is essential in a tropical context where soil degradation is a concern. These results could stimulate further research on the interactions between mycorrhizae, plants and organic fertilizers.

• #berry genetics and cultivation research
• #plant growth enhancement techniques
• #microbial metabolites in food biotechnology
• #fertilizer

Treatment of Slaughterhouse Effluents by Planted Filter with Echinochloa pyramidalis

Noukeu Nkouakam Armelle, Paul Agendia Atabong, Gabriel Mahbou Somo Toukam, Emmanuel Djafna, Libert Brice Tonfack, Emmanuel Youmbi

OALib

Slaughterhouse wastewater is among the most environmentally hazardous wastewater.These waters are discharged into the environment without treatment.The objective of this study is to evaluate the effect of different concentrations of slaughterhouse wastewater on the purification performance of Echinochloa pyramidalis planted filters.During the study, slaughterhouse wastewater was collected in 10 l polystyrene bottles in 14-days intervals and then characterized for physicochemical and bacteriological parameters according to the standard protocol.Four planted filter treatment devices with Echinochloa pyramidalis were mounted with four different concentrations of slaughterhouse wastewater T1: 25% wastewater + 75% tap water; T2: 50% wastewater + 50% tap water; tap; T3: 75% wastewater + 25% tap water and T4: 100% raw wastewater.The purification performances as well as the morphometric parameters were determined.The results obtained show values of MES (54115 745 mg/L); nitrate (3225.75 448.91 mg/L); COD (13592.17 2007.31 mg/L) and CF (523,333.8 35,555,909 CFU/100 mL) very high compared to the discharge standards.Treatment T1 showed the best performance.However, the values obtained are always above the standards.Hence, the need for optimization or post-treatment of slaughterhouse effluents to reduce as much as possible the pollutant loads of these wastewaters before their discharge.

• #constructed wetlands for wastewater treatment
• #echinochloa
• #effluent
• #environmental science

A review of population genetics and the prospects for crop improvement

Godswill Ntsomboh Ntsefong, Gabriel Mahbou Somo Toukam, Benoit Constant Likeng-Li-Ngue, Kingsley Tabi Mbi, Seyum Getachew Essubalew, Mohammad Ali Shariati et 4 autre(s)

Academia Biology

This study discusses the importance of population genetics in the context of crop improvement and its role in addressing challenges related to food security. Population genetics is crucial in identifying desirable traits and genetic markers, developing breeding strategies and improving the efficacy of crop improvement programs. The Food and Agriculture Organization of the United Nations emphasizes the importance of crop improvement in addressing global food security challenges and highlights the role of population genetics in improving crop yields, developing new varieties, and increasing the resilience of crops to environmental stressors. By using population genetics to improve crop yields, disease resistance, and other desirable traits, breeders can help ensure a sustainable and secure food supply for future generations.

• #genetic and environmental crop studies
• #seed and plant biochemistry
• #agriculture and biological studies
• #crop

Floral biology, Field Controlled Pollination and Hybrid Obtention of Dioscorea Dumetorum (Kunth) Pax) in Cameroon

Gabriel Mahbou Somo Toukam, Eddy Ngonkeu, Godswill Ntsomboh-Ntsefong, Marie Noel Ateko Tiokeng, Emmanuel Youmbi

Global Journal of Human Social Science

Introduction-There is very little literature on the floral biology, synchronization of maturity of male and female flowers, flowering phenology and controlled pollination of Dioscorea dumetorum (D. dumetorum). However, the genetic improvement of this yam species, which is widely consumed in Cameroon and has exceptional nutritional qualities, cannot be achieved without knowledge and understanding of these biological attributes or phenomena. The aim of this study was to (1) -examine the sexual reproductive biology of D. dumetorum; (2) -study the phonology of flowering in this plant species; and (3) -develop a pollination method in order to obtain hybrid seedlings.

• #potato plant research
• #biology
• #pollination
• #phenology

Influence of Cultivar on the Postharvest Hardening of Trifoliate Yam ( Dioscorea dumetorum ) Tubers

Christian Siadjeu, Emmanuel Akdowa Panyoo, Gabriel Mahbou Somo Toukam, Joseph Martin Bell, Benoit Nono, Gabriel Nama Medoua

Advances in Agriculture

The influence of cultivar on the postharvest hardening of Dioscorea dumetorum tubers was assessed. 32 cultivars of D. dumetorum tubers were planted in April 2014, harvested at physiological maturity, and stored under prevailing tropical ambient conditions (19–28°C, 60–85% RH) for 0, 5, 14, 21, and 28 days. Samples were evaluated for cooked hardness. Results showed that one cultivar, Ibo sweet 3, was not affected by the hardening phenomenon. The remaining 31 were all subject to the hardening phenomenon at different degree. Cooked hardness increased more rapidly in cultivars with many roots on the tuber surface compared to cultivars with few roots on the tuber surface. When both the characteristics flesh colour and number of roots on tuber surface were associated, cooked hardness in cultivars with yellow flesh and many roots increased more rapidly than in cultivars with white flesh and many roots, whereas cooked hardness in cultivars with yellow flesh and few roots increased more slowly than in cultivars with white flesh and few roots. Accessions collected in high altitude increased more rapidly compared to accessions collected in low altitude. The cultivar Ibo sweet 3 identified in this study could provide important information for breeding program of D. dumetorum against postharvest hardening phenomenon.

• #botanical research and applications
• #postharvest quality and shelf life management
• #plant physiology and cultivation studies
• #cultivar

Broad diversity of Ralstonia solanacearum strains in Cameroon : [P4-81]

Gabriel Mahbou Somo Toukam, Gilles Cellier, Emmanuel Wicker, Caroline Guilbaud, Rémi Kahane, Caitilyn Allen et 1 autre(s)

In 2005, an extensive survey of bacterial wilt in Cameroon collected 110 strains of #Ralstonia solanacearum# from wilting tomato, potato, pepper, huckleberry (Solanum scabrum), sesame, and amaranth. The genetic diversity and phylogeny of selected strains from Cameroon were assessed by multiplex-polymerase chain reaction (PCR), race 3/biovar 2-specific PCR, and sequence analyses of the mutS and egl genes. These data were compared with those from 33 reference strains covering the known diversity within the R. solanacearum species complex. Strains isolated in Cameroon clustered into three of the four known phylotypes: I (Asian), II (American), and III (African). Lowland tomato strains belonged to phylotype I and were quite homogeneous. The strains belonging to phylotype II were genetically diverse, and partitioned into subclusters IIA and IIB (sequevar 1, race 3/biovar 2). Cameroon strains in the African phylotype III were distinct from reference strains from Zimbabwe or the Indian Ocean, highlighting the genetic diversity present within this phylotype. Strains from potatoes growing in the highlands of West Cameroon fell into both phylotypes II (race 3/biovar 2) and III. These phylotype II and III highland strains attacked both potato and tomato and could therefore pose an economic threat to potato and tomato crops throughout Central Africa. This is the first comprehensive report on the genetic diversity of #R. solanacearum# strains in Cameroon. (Resume d'auteur)

• #plant pathogenic bacteria studies
• #plant pathogens and fungal diseases
• #banana cultivation and research
• #phylotype

Broad Diversity of Ralstonia solanacearum Strains in Cameroon

Gabriel Mahbou Somo Toukam, Gilles Cellier, Emmanuel Wicker, Caroline Guilbaud, Rémi Kahane, Caitilyn Allen et 1 autre(s)

Plant Disease

In 2005, an extensive survey of bacterial wilt in Cameroon collected 110 strains of Ralstonia solanacearum from wilting tomato, potato, pepper, huckleberry (Solanum scabrum), sesame, and amaranth. The genetic diversity and phylogeny of selected strains from Cameroon were assessed by multiplex-polymerase chain reaction (PCR), race 3/biovar 2-specific PCR, and sequence analyses of the mutS and egl genes. These data were compared with those from 33 reference strains covering the known diversity within the R. solanacearum species complex. Strains isolated in Cameroon clustered into three of the four known phylotypes: I (Asian), II (American), and III (African). Lowland tomato strains belonged to phylotype I and were quite homogeneous. The strains belonging to phylotype II were genetically diverse, and partitioned into subclusters IIA and IIB (sequevar 1, race 3/biovar 2). Cameroon strains in the African phylotype III were distinct from reference strains from Zimbabwe or the Indian Ocean, highlighting the genetic diversity present within this phylotype. Strains from potatoes growing in the highlands of West Cameroon fell into both phylotypes II (race 3/biovar 2) and III. These phylotype II and III highland strains attacked both potato and tomato and could therefore pose an economic threat to potato and tomato crops throughout Central Africa. This is the first comprehensive report on the genetic diversity of R. solanacearum strains in Cameroon.

• #plant pathogenic bacteria studies
• #plant-microbe interactions and immunity
• #plant disease resistance and genetics
• #phylotype

Diversité génétique des souches camerounaises de Ralstonia solanacearum : [Poster]

Gabriel Mahbou Somo Toukam, Caroline Guilbaud, Philippe Prior

CIRAD-FLHOR eBooks

• #plant pathogenic bacteria studies
• #cassava research and cyanide
• #african botany and ecology studies
• #ralstonia solanacearum

Diversité des souches camerounaises de Ralstonia solanacearum

Gabriel Mahbou Somo Toukam, Caroline Guilbaud, Philippe Prior

• #plant pathogenic bacteria studies
• #cassava research and cyanide
• #infections and bacterial resistance
• #ralstonia solanacearum

Identification of major diseases of the common bean (Phaseolus vulgaris L.) in Cameroon and evaluation of their possible reestablishment in the Centre province of Cameroon

Daniel Fotio, Julienne Nguefack, C. Zonkeng Guepi, O.A. David, Nounamo Laurent, Gabriel Mahbou Somo Toukam et 3 autre(s)

Agritrop (Cirad)

Bean is a high source of vegetal protein in Africa. However its culture suffers many constraints among which seed-borne diseases are of great importance. The purpose of this study was to collect common beans (Phaseolus vulgaris L.) and to survey the disease agents responsible for the low production of this crop in Cameroon, especially in the Centre Province of this country. Twenty five (25) varieties of common bean seeds were collected from different agroecological zones of Cameroon, and cultivated in a sole crop system at Minkoameyos (Yaounde, Cameroon) between the 07th of October 2003 and the 25th of January 2004. The experimental site was characterised by three soil indicators: low pH (5.53), low C/P ratio (81.95) and normal C/N ratio (22.40). The experimental unit consisted of area of 8 m2 (4 m x 2 m). The experimental design was a randomized complete block design with 3 replications. The record of disease symptoms started four weeks after planting using the Compendium of Bean Diseases. The Liquid Assay method allowed the identification of Xanthomonas axonopodis pv. phaseoli and its variant fuscans, Pseudomonas syringae pv. phaseolicola and Pseudomonas syringae pv. syringae as major agents responsible for the common and fuscous bacterial blights, halo blight and brown spot respectively, on infected leaves and seeds. In addition, symptoms of the following diseases were observed in the field: ascochyta blight (Phoma exigua var. diversispora), anthracnose (Colletotrichum lindemuthianum), angular leaf spot (Phaeoisariopsis griseola), floury leaf spot (Mycovellosiella phaseoli), bean common mosaic and black root (Bean common mosaic virus), and of insect pest "le cigare" (Apoderus humeralis). The yield average ranged from 0.046 t/ha to 0.821 t/ha. This low yield was correlated with disease damages observed in the field. (Texte intégral)

• #plant pathogens and resistance mechanisms
• #plant pathogenic bacteria studies
• #agricultural pest management studies
• #phaseolus