Libert Brice TONFACK

Editorial: Integration of legume intercropping into sustainable farming systems for nitrogen fixation, soil health, and climate resilience

Libert Brice Tonfack, Sudhir Kumar Rajpoot, Keston Njira

Frontiers in Sustainable Food Systems

Soil health describes a soil's capacity to function within its ecological boundaries-supporting plant growth, sustaining water and air quality, and maintaining robust microbial and animal life. It's critical to ecosystem's ability to deliver services such as food production, nutrient cycling, carbon storage, and biodiversity support (Pinto et al., 2017). Unfortunately, converting native landscapes into monocultures and relying heavily on synthetic fertilizers depletes soil organic matter, damages microbial communities, and lowers water retention, weakening these essential services.The incorporation of legumes in various cropping systems holds immense potential for addressing numerous challenges in modern agriculture, from improving soil health to enhancing crop yields and combating climate change. As biologically nitrogen-fixing crops, legumes naturally enrich the soil and reduce dependence on chemical fertilizers. They also enhance soil structure, promote microbial life, suppress insect pests and weeds, improve water use efficiency (Kokkini et al., 2025;Akchaya et al., 2025;Rajpoot et al., 2016), improve crop nutritional quality and production sustainability (Nuemsi et al., 2018). These "service crops" align with the economic, social, and environmental goals of sustainable agriculture. Despite its potential, the adoption of legume intercropping remains limited by the lack of suitable adaptation strategies across various climates and socio-economic contexts (Akchaya et al., 2025). Practical agronomic recommendations, such as optimal spacing, sowing methods, and management based on local conditions, are still emerging as research advances.This Research Topic aimed to address these needs by compiling high-quality contributions provided by individual studies and reviews on the subject of legume intercropping and its role in sustainable agricultural practices. These works focus on: i) Nutrient cycling and nitrogen fixation, human-centered ecosystem services, ii) Soil quality and physico-chemical properties, iii) Crop productivity and resilience, iv) Microbial and pest interactions, and v) Resource use efficiency and climate adaptation.This collection brings together nine insightful contributions that explore the ecological and agronomic roles of legume intercropping across diverse farming systems, from rice-fallows in India to maize-peanut fields and high-altitude grasslands. The studies compiled in this Research Topic underscore the diverse and essential ecosystem services offered by legumes when integrated into intercropping systems. From enhancing nutrient cycling and biological nitrogen fixation to improving soil structure, microbial activity, and crop resilience, legumes consistently demonstrate their potential as cornerstone crops in sustainable agriculture. The success of legume intercropping depends on many factors like local climate, soil conditions, crop combinations, and how farmers manage their fields. To make it truly effective, region-specific practices, farmer involvement, and practical recommendations are essential. Future efforts should focus on long-term studies, develop suitable agronomic packages, and explore how legumes interact with soil life, especially under changing climates. Understanding the economic trade-offs and offering market support will also help farmers adopt these systems more widely.In conclusion, legumes offer a practical and ecologically grounded solution to many of the pressing challenges in agriculture. Their role in building resilient, efficient, and sustainable agroecosystems continues to grow, and this Research Topic contributes meaningfully to the scientific and practical understanding of their multifaceted value.

• #agronomic practices and intercropping systems
• #agricultural pest management studies
• #seed and plant biochemistry
• #intercropping

Effect of Distillery Effluent on Seed Germination in Some Crops

Armelle Noukeu Nkouakam, Valerie Franck Tchassem Nouayou, Libert Brice Tonfack, Zachée Ambang

Scholars Journal of Agriculture and Veterinary Sciences

The present study has been undertaken to evaluate the effect of distillery effluent (stillage) on seed germination in Zea mays, Phaseolus vulgaris and Arachis hypogaea. The effect of different concentrations T0 (tap water), 10% (T1), 20% (T2), 50% (T3), 75% and T5 (100% of distillery effluent) on seed germination percentage, vigor index, tolerance index, phytotoxicity percentage, number of seed germination, the length of the radicle, seedling length, root length and radicle length were recorded for each plant species after 15 days. For Zea mays, T2 has the highest germination percentage; followed by T3 for Phaseolus vulgaris and by T0 for Arachis hypogea. The phytotoxicity percentage is high in T5 for Phaseolus vulgaris. The diluted effluent had statistically significant effects on the measured parameters. The high concentrations of stillage inhibited the root and radicle length of seedlings in Arachis hypogaea. Based on the tolerance to distillery effluent, the crops studied have been arranged in the following order Zea mays > Phaseolus vulgaris > Arachis hypogaea. The seed germination and growth parameters increased in lower (10% et 20%) concentrations of distillery effluent and the morphological parameters gradually decreased with increasing effluent concentration. We conclude that the effect of the distillery effluent is crop-specific and due care should be taken before using the distillery effluent for irrigation purposes.

• #wastewater treatment and reuse
• #germination
• #effluent
• #agronomy

Effect of osmopriming with PEG 6000 on seed germination performance and early seedling establishment in okra (Abelmoschus esculentus (L.) Moench)

Michaël Kenne Fomekong, Elise Fabiola Tchouake Tetang, Nono Carine Temegne, Jordan Ulrich Engoulou Minlo, Paul Agendia Atabong, Alanis Cindy Noadje Kameni and 3 more

Research Square

• #seed germination and physiology
• #agricultural practices and plant genetics
• #plant growth enhancement techniques
• #seedling

Effect of osmopriming with PEG 6000 on seed germination performance and early seedling establishment in okra (Abelmoschus esculentus (L.) Moench)

Michaël Kenne Fomekong, Elise Fabiola Tchouake Tetang, Nono Carine Temegne, Jordan Ulrich Engoulou Minlo, Paul Agendia Atabong, Alanis Cindy Noadje Kameni and 3 more

Discover Plants.

Enhancing plant production requires advancing seed germination processes despite environmental constraints. Dry soils often reduce okra yield by hindering seed germination and plant growth. Seed pre-treatment could alleviate water shortage problems. This study aims to identify the optimal Osmopriming with PEG 6000 condition for promoting seedling establishment in okra. We used PEG 6000 solutions with increasing concentrations (Hp, C: 0.0 MPa; T1: − 0.3 MPa; T2: − 0.6 MPa; T3: − 0.9 MPa; and T4: − 1.2 MPa) to treat okra seeds for 1, 3, 7 and 9 h. The experiment was conducted using a fully randomized setup with three simultaneous replications, and we measured key parameters as germination rate, seedling viability, vigor, and physiological parameters. The main findings of the analysis are that water stress has a repressive impact on germination and seedling development in both okra varieties (Clemson spineless and Hire). Osmotic pretreatments consistently enhanced germination parameters and seedling development, irrespective of the priming duration, particularly showing an improved response in the Clemson spineless variety. In comparison to the control group, seeds of the Clemson spineless variety that were pretreated exhibited the highest germination rate (95.83%), the highest seedling viability (93.94%), and the greatest seedling vigor (10.61). The highest seedling height (11.55 cm) was achieved in PEG 6000 at a pressure of − 0.6 MPa for 9 h. Under priming conditions, the seedlings of the Clemson Spineless variety exhibit an increase in various physiological parameters. The highest values are observed using seeds treated with PEG 6000 at − 0.6 MPa for 9 h (2.77 mg/g for chlorophyll a; 1.62 mg/g for chlorophyll b; 4.40 mg/g for total chlorophyll, and 6.09 mg/g for carotenoids) compared to the control. Despite the depressive impact of PEG 6000-induced water stress on germination and seedling development, the use of PEG 6000 as a priming promotes germination and seedling development in okra. To achieve optimal okra production in arid or semi-arid environments, it is recommended to utilize seeds of the Clemson Spineless variety that have been osmoprimed with PEG 6000 at a pressure of − 0.6 MPa for 9 h. Graphical abstract

• #seed germination and physiology
• #agricultural science and fertilization
• #agricultural practices and plant genetics
• #seedling

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 and 5 more

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

Mycotrophic Status of Strawberry (<i>Fragaria</i> spp.) Suggests High Potential for Sustainable Fruit Production in Sub-Saharan Africa

Laura Scottie Ngouana-Tchinda, Carine Temegne-Nono, E.L. Ngonkeu-Mangaptche, Michaël Fomekong-Kenne, Landry Thierry Dongmo-Voukeng, Thérèse Dalida Nkou Foh and 2 more

Agricultural Sciences

Little is known about the mycotrophic status and biological production of strawberries in sub-Saharan Africa. This study investigated arbuscular mycorrhizal fungi (AMF) in the rhizospheres of strawberries from two agroecological zones (AEZs) in Cameroon: AEZ III (Western Highlands) and AEZ V (bimodal rainforest). AMF spores were identified from trapping soil, while strawberry roots were assessed for colonization. Two Fragaria spp. varieties, “Madame moutot” and “Mara des bois”, were cultivated in both AEZs. The soils were acidic and deficient in available phosphorus (4.9 and 0.88 mg.kg−1) with imbalanced Ca:Mg:K ratios (55:22:23 and 46:34:23) respectively. Three fertilization treatments were used: 1) control (unfertilized); 2) mineral (N:P:K 13:13:21); and 3) AMF species complex (at 30 g.plant−1) in a split-plot design with four replicates. Thirteen AMF species across seven genera were identified in the rhizospheres (11 in AEZ III and 12 in AEZ V). The spores measured 45 - 250 µm in diameter. Diversity indices (Shannon-Wiener and Simpson’s) indicated no specific dominance of AMF species. AMF fertilizer enhanced strawberry production and fruit quality, improving leaf formation, runners, and fruits per plant, fruit weight, and nutrient contents. This study confirms that strawberries are mycotrophic, and AMF-based fertilizers can enhance biological production in sub-Saharan African soils. Graphical abstract

• #berry genetics and cultivation research
• #plant-microbe interactions and immunity
• #plant pathogens and fungal diseases
• #spore

Soursop (Annona muricata L.) seed extracts: phytochemical composition and biocontrol potential against cercosporiosis in okra (Abelmoschus esculentus L. Moech)

Hubert Bolie, Libert Brice Tonfack, Sylvère Landry Lontsi Dida, Patrice Zemko Ngatsi, Juste Philantrope Abega, Eric Bilo’a Ndongo and 3 more

Investigational Medicinal Chemistry and Pharmacology

Background: Annona muricata, or soursop, is a tropical plant known for antimicrobial and antiparasitic properties, widely used in traditional remedies. Extracts from leaves, seeds, and bark show activity against pathogens in humans and plants, making it a promising candidate for natural biopesticide development as safer alternatives to chemical controls. This study evaluates Annona muricata seed extracts as bio-fungicides against Cercospora leaf spot in okra under field conditions. Methods: Capillary gas chromatography and mass spectrometry (GC-MS) analyzed aqueous and organic (acetone, ethyl acetate, and methanol) extracts. Two okra varieties (V1 and V2) were tested in field trials during 2019 and 2020. Six treatments included control, synthetic fungicide (3.33 g/L), aqueous extract (33.33 g/L), and methanol, acetone, and ethyl acetate extracts (1:600 v/v). Disease incidence, severity, and yield were measured. Results: GC-MS identified eight antifungal compounds (hexadecanoic acid methyl ester, hexadecanoic acid ethyl ester, hexadecane, n-hexadecanoic acid, octadecanoic acid methyl ester, 9-octadecanoic acid ethyl ester, and 10-octadecadienoic acid (Z,Z)-methyl ester), though these were not directly tested in this study. The Cercospora incidence at 12 weeks after sowing was significantly reduced from 51.11 % and 47.82 % in control plots during 2019 and 2020, respectively, to 8.88 % and 6.64 % in plots treated with aqueous extract and 9.99 % and 9.76 % in plots treated with methanol extract. Yields were highest with aqueous extract (6.48 and 5.22 t/ha), outperforming methanol extract, synthetic fungicide, and control. Conclusion: Bio-fungicides from Annona muricata extracts offer environmentally friendly options for managing okra cercosporiosis

• #agricultural practices and plant genetics
• #insect pest control strategies
• #agricultural pest management studies
• #abelmoschus

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

Unlocking African bioeconomy through biodiversity genomics and bioinformatics

Ichrak Hayah, Victor Ezebuiro, Samuel Paul Kagame, Josiah Kuja, Cecilia Waruhiu, Lucky T. Nesengani and 94 more

The African BioGenome Project (AfricaBP) is a Pan-African initiative aimed at improving food systems and biodiversity conservation through genomics while ensuring equitable data sharing and benefits. The Open Institute is the knowledge exchange platform of the AfricaBP which aims to bridge local knowledge gaps in biodiversity genomics and bioinformatics and enable infrastructural developments. In 2024, the AfricaBP Open Institute advanced this mission by organising 31 workshops that attracted more than 3500 registered attendees and trained 380 African researchers in genomics, bioinformatics, molecular biology, sample collections and biobanking, and ethics, across all five African geographical regions involving 40 African and non-African organizations. These workshops provide current understanding on the applications of biodiversity genomics and bioinformatics to the African bioeconomy as well as providing practical and hands-on training in genomics, bioinformatics, molecular biology, gene editing, and sample collection and processing. Here, we provide the current understanding of the applications of biodiversity genomics and bioinformatics to the African bioeconomy through synthetic reviews and presentations, including descriptions of 31 workshops organised as well as three fellowship programs delivered or launched by the AfricaBP Open Institute in collaboration with African and international institutions and industry partners. We review the current national bioeconomy strategies across Africa and the economic impact of sequencing African genomes locally, illustrated by a case study on the proposed 1000 Moroccan Genome Project. Finally, we provide recommendations on how African countries could integrate biodiversity genomics and bioinformatics into national economic plans and bioeconomy strategies.

• #bioeconomy and sustainability development
• #genomics
• #biodiversity
• #computational biology

Unlocking the African bioeconomy and strengthening biodiversity conservation through genomics and bioinformatics

Ichrak Hayah, Victor Ezebuiro, Samuel Paul Kagame, Josiah Kuja, Cecilia Waruhiu, Lucky T. Nesengani and 94 more

npj Biodiversity

The African BioGenome Project (AfricaBP) is a Pan-African initiative aimed at improving food systems and biodiversity conservation through genomics while ensuring equitable data sharing and benefits. The Open Institute is the knowledge exchange platform of the AfricaBP, which aims to bridge local knowledge gaps in biodiversity genomics and bioinformatics and enable infrastructural developments. In 2024, the AfricaBP Open Institute advanced this mission by organizing 31 workshops that attracted more than 3500 registered attendees across 50 African countries, provided training to 401 African researchers in genomics, bioinformatics, molecular biology, sample collections and biobanking, and ethical considerations, across all five African geographical regions involving 40 African and non-African organizations. These workshops provide insights on applications of biodiversity genomics and bioinformatics to the African bioeconomy, as well as hands-on training in sample collection and processing, genomics, bioinformatics, molecular biology, and gene editing. Here, we provide the current understanding of the applications of biodiversity genomics and bioinformatics to the African bioeconomy through synthetic reviews and presentations, including descriptions of 31 workshops organized as well as three fellowship programs delivered or launched by the AfricaBP Open Institute in collaboration with African and international institutions and industry partners. We review the current national bioeconomy strategies across Africa and the economic impact of sequencing African genomes locally, illustrated by a case study on the proposed 1000 Moroccan Genome Project. Key recommendations include integrating biodiversity genomics and bioinformatics into national bioeconomy strategies, leveraging genomics for sustainable bioeconomy growth, and expanding capacity-building initiatives across Africa.

• #crispr and genetic engineering
• #genetics, bioinformatics, and biomedical research
• #bioeconomy and sustainability development
• #genomics

Establishing African genomics and bioinformatics programs through annual regional workshops

Abdoallah Sharaf, Lucky T. Nesengani, Ichrak Hayah, Josiah Kuja, Sinebongo Mdyogolo, Taiwo Crossby Omotoriogun and 94 more

Nature Genetics

• #genetics, bioinformatics, and biomedical research
• #biotechnology and related fields
• #biomedical and engineering education
• #biology

Evaluating the Effect of Salt Stress Conditions on the Growth, Yield and Nutrient Composition of Calyces and Leaves of Roselle (Hibiscus sabdariffa L.) Cultivars in Far North Region of Cameroon

Mathias Julien Hand, Alphonse Ervé NOUCK, Libert Brice Tonfack, Kingsley Mbi Tabi, Victor Desiré Taffouo, Emmanuel Youmbi

Context: In sahelian and coastal areas, salinity is a permanent treat to the growth and devolpment of plants. The choice of salt-tolerant species would be a solution to this constraint. Objective: The purpose of this work was to study the effect of the different NaCl concentrations on the growth, the yield and the nutritional composition of leaves and the calyx in two cultivars of Roselle (Hibiscus sabdariffa L.) i.e: green bissap and red star. Methodology: The plants were subjected to different doses of NaCl ranging from 0, 60, 120 to 240 mM for 60 days in a completely random blocking design having four block. Results: Increase in NaCl levels had no appreciable effect on growth, yield and chemical composition of leave and calyce of roselle. Application of NaCl (from 0 to 240 mM) led to a decrease of leaf yield (27.5% and 24.7% in Red star and Green bissap respectively), calyce yield (23.1% and 31.6% in Red star and Green bissap respectively), seed yield (29.8% and 32.8% in Red star and and Green bissap respectively) and accumulation of osmolytes, fiber content, Na content of leave and calyce and total anthocyanin content of calyce (25% and 66.5% in Red star and Green bissap respectively). The Na+ content obtained in the aerial parts (leave and calyce) was very low in the Red star cultivar and high in Green bissap. Conclusion: The Red star (red bissap) cultivar is more salt tolerant than the Green bissap and therefore suggests that it could be a promising crop for farmers in salinity-prone areas and the coastal belts in tropical and sub-tropical regions.

• #hibiscus plant research studies
• #african botany and ecology studies
• #hibiscus sabdariffa
• #cultivar

Integration of Water Quality Indices and Multivariate Analysis to Evaluate Slaughterhouse Effluent Pollution in the Ako'O River, Cameroon

Atabong Paul Agendia, Wafo Guy Valerie Djumyom, Kengne Ebenezer Soh, Tekamdjio Stephane Lauris Tchianzeu, Kenne Michaël Fomekong, Fankem Jean Pierre Noutadie and 2 more

SSRN Electronic Journal

• #water quality and pollution assessment
• #water quality monitoring and analysis
• #effluent
• #water quality

Repurposing of Plant-based Antiviral Molecules for the Treatment ofCOVID-19

Jabeena Khazir, Sajad Ahmed, Rakesh Thakur, Manzoor Hussain, Sumit G. Gandhi, Sadhana Babbar and 7 more

Current Topics in Medicinal Chemistry

Abstract: COVID-19, stemming from SARS-CoV-2, poses a formidable threat to global healthcare, with a staggering 77 million confirmed cases and 690,067 deaths recorded till Decem-ber 24, 2023. Given the absence of specific drugs for this viral infection, the exploration of novel antiviral compounds becomes imperative. High-throughput technologies are actively engaged in drug discovery, and there is a parallel effort to repurpose plant-based molecules with established antiviral properties. In this context, the review meticulously delves into the potential of plant-based folk remedies and existing molecules. These substances have showcased substantial viral inhibition in diverse in vivo, in silico, and in vitro studies, particularly against critical viral protein targets, including SARS-CoV-2. The findings position these plant-based molecules as promising antiviral drug candidates for the swift advancement of treatments for COVID-19. It is noteworthy that the inherent attributes of these plant-based molecules, such as their natural origin, potency, safety, and cost-effectiveness, contribute to their appeal as lead candidates. The review advocates for further exploration through comprehensive in vivo studies conducted on animal models, em-phasizing the potential of plant-based compounds to help in the ongoing quest to develop effec-tive antivirals against COVID-19.

• #transgenic plants and applications
• #toxin mechanisms and immunotoxins
• #herbal medicine research studies
• #repurposing

Seed germination, morphology and fruit phenology insight of Cylicomorpha solmsii (Urb.) Urb: a step towards sustainable restoration planning

Raissa Fon Na-ah, Nadine Ndabeh Ngwa, Liliane Ngoune Tandzi, Eric Ngansop Tchatchouang, Dessireé Zerpa‐Catanho, Emmanuel Youmbi and 1 more

Scientific Reports

Cylicomorpha solmsii (Urb.) Urb (Caricaceae) is a wild relative of domesticated Carica papaya native to the humid tropical forest of Cameroon. C. solmsii is becoming extinct due to rapid urbanization of its habitat. There is currently no restoration planning, no available data on seed germination, details on morphological description and fruit phenology. We investigated the effects of light and soil on seed germination, updated its morphological description and provided cues of its fruit phenology. In two series of experiments, a germination test was first conducted under light and dark conditions with three seed pre-treatments (scarification, drying and cold). Secondly, pre-treated seeds were sown in native soils of C. solmsii habitat collected at Eloumden I and II, two ex-situ and mixtures soil with sand. Qualitative and quantitative data were collected on different part of the plant and analyzed using R package version 4.3.2. Our findings showed that C. solmsii seeds can germinate only under light. The seeds manifested a physiological embryonic dormancy. The native soils showed the highest germination percentage and seedling establishment. The dioicy of C. solmsii was clearly described with incomplete staminate and pistillate unisexual flower whorls. C. solmsii was observed to produce fruits throughout the year at varying intensity. This information is a vital cue to species restoration and policy makers towards C. solmsii conservation.

• #african botany and ecology studies
• #plant diversity and evolution
• #seed germination and physiology
• #germination

Current status of strawberry (Fragaria spp.) cultivation and marketing in Cameroon

Laura Scottie Tchinda Ngouana, Libert Brice Tonfack, Nono Carine Temegne, Atabong Paul Agendia, Emmanuel Youmbi

Journal of Agriculture and Food Research

Strawberries are among the most consumed fruits in the world, offering a multitude of health benefits. Their popularity has contributed to their economic value. However, in Cameroon, there is an insufficiency of strawberry yields, resulting in their importation and high market prices. Consequently, strawberries have become a luxury item, out of reach for the average citizen. This study carries out the inventory of the technique of production and marketing of strawberries in Cameroon. In 2021, a survey of one hundred and one strawberry farmers in three regions: the Center, the West, and the South was conducted. The survey collected information on the socio-demographic characteristics of strawberry farmers, cultivation practices, and production. Additionally, we interviewed supermarkets, pastry chefs, and canvassers to gather data on strawberry marketing practices. Male strawberry farmers (83.17%) outnumbered females (16.83%). The majority of farmers (65.35%) practiced mix cropping, especially with tomatoes, while 34.65% focused on monoculture. Back pain and pests were identified as the major constraints. The educational level and age were found to be influential factors in farmers' proposals for improving yields. On average, 1 kg of strawberries in Cameroon costs 10,000 XAF. The main customers are canvassers, supermarkets, and pastry chefs, who prioritize the size of the fruit when making purchases. The number of strawberry farmers is higher in the West region. It takes up to 1,000,000 XAF to initiate cultivation when the area is as from 1000 m2. The high cost of strawberries is due to their scarcity.

• #berry genetics and cultivation research
• #horticultural and viticultural research
• #pineapple and bromelain studies
• #business

Histological and biophysical changes of cassava roots during retting, a key step of fufu processing

G. A. Wakem, Libert Brice Tonfack, Emmanuel Youmbi, Apollin Fotso Kuate, Cargele Masso, Komi K. M. Fiaboe and 6 more

Journal of the Science of Food and Agriculture

Abstract BACKGROUND Retting is a key step of cassava processing into widely consumed foods (fufu, chikwangue, miondo and bobolo) in sub‐Saharan Africa. For some populations, retting ability is a major quality criterion that drives the adoption of new cassava varieties. Despite this importance, the physiological basis associated with this process remains poorly understood, and should lead to improved screening tools for breeding. Eight cassava varieties contrasting in retting ability properties were used in the present study. Roots and soaking water were sampled during retting and characterized at both histological and biochemical levels. RESULTS Histological data highlighted the degradation of root cell wall during retting. The average pH of soaking water decreased from 5.94 to 4.31 and the average simple sugars decreased from 0.18 to 0 g L −1 , whereas the organic acids increased up to 5.61 g L −1 . In roots tissue, simple sugars and organic acid contents decreased from 22.9 to 0 g kg −1 and from 80 to 0 g kg −1 , respectively. The total pectin content of roots among varieties at harvest was similar, and decreased during the retting process. Overall, there was a negative correlation between total pectins content and root softening, although this did not reach statistical significance. CONCLUSION Major histological and biochemical changes occurred during cassava root retting, with some of them associated with the process. Retting affected starch pasting properties more than starch content. Although this process is characterized by root softening and degradation of cell wall structure, the present study strongly suggested that pectin is not the only cell wall component involved in these changes. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

• #cassava research and cyanide
• #food composition and properties
• #plant micronutrient interactions and effects
• #retting

Influence of Harvest Periods on Cassava (<i>Manihot esculenta</i> Crantz) Agronomic Traits and Physiological Response to Post-Harvest Physiological Deterioration

Astride Stéphanie Mouafi Djabou, Herman Pascal Kounty Ewane, Victor Jos Evina Eyamo, Franklin Tounkam Ketchiemo, Priscila Gonzáles Figueiredo, Nicolas Niemenak and 1 more

American Journal of Plant Sciences

Cassava (Manihot esculenta Crantz) is the third largest source of calories in tropical countries and the sixth most important food crop in the World. However, the short shelf life of its storage roots after harvest due to a rapid post-harvest physiological deterioration (PPD) makes the roots to be considered as a risky product to market. The objectives of this work were to investigate the influence of two harvest periods on cassava agronomic parameters and their physiological response to PPD. Three cassava cultivars 96/1414, I070593 and LMR were selected for the experiment and harvested at 10 and 12 months after planting (MAP). The response to PPD was assessed during storage at 0, 3, 8 and 15 days after harvest (DAH). Total proteins content, soluble sugars and starch, total polyphenols compounds, polyphenoloxidase and peroxidase activities were recorded during storage. Results showed large variation among the parameters at the two harvest periods across the cultivars. High number of tubers was recorded in all the cultivars at 12 MAP and a significant increase in storage roots length was observed in 96/1414 and LMR from 10 MAP to 12 MAP (25 ± 5.1 to 41.3 ± 5.9 and 22.6 ± 3.3 to 27.9 ± 4.8) respectively. A reduction of about 49% of tubers weight was observed in I070593 from 10 to 12 MAP while an increase of about 36% and 11% were recorded in LMR and 96/1414 respectively. Tubers from I070593 showed less susceptibility to PPD when harvested at 10 MAP compared to those from LMR and 96/1414 where less susceptibility to PPD were recorded at 12 MAP. An increase in soluble sugars content, total proteins content and peroxidase activity subsequently to a decrease in starch content were recorded during storage from 8 to 15 days after harvest especially at 10 MAP in I070593 and at 12 MAP in LMR and 96/1414. High content of total phenolic compounds and less activity of polyphenol oxidase were correlated to PPD susceptibility. This work opens a new insight issue of the consideration of the appropriate harvest time of the cultivars as a tool to better control the onset of postharvest physiological deterioration.

• #cassava research and cyanide
• #botanical research and applications
• #plant micronutrient interactions and effects
• #manihot esculenta

Micropropagation from cotyledonary explants of grapefruit (<i>Citrus</i> <i>paradisi</i> Macf.) by indirect and direct organogenesis

Darius Tchoutang Nzepang, Libert Brice Tonfack, Bilal Ahmad Mir, Emmanuel Noumsi-Foamouhoue, Emmanuel Youmbi

Cameroon Journal of Experimental Biology

Grapefruit (Citrus paradisi Macf.) is an economic fruit crop worldwide cultivated for its nutritional value, and aromatic flavours. However, the development of new varieties and high production of quality seedling constitutes a limit to improving grapefruit yields. An efficient regeneration protocol could be of great interest for grapefruit transformation, micropropagation, and germplasm conservation. In vitro plant regeneration systems of Citrus paradisi have been studied by using cotyledonary explants. Different concentrations of plant growth regulators were used to explore the organogenic potential of cotyledonary explants under laboratory conditions. For indirect organogenesis using cotyledon segment explants, a low concentration of 2,4-dichlorophenoxyacetic acid (2,4-D) lead to the formation of white callus, while a high concentration of 2,4-D induced brown callus and adventitious root differentiation. The best response for callogenesis was obtained on Murashige and Skoog (MS) medium supplemented with 2 mg/L of 2,4-D. Only brown callus cultured on MS added with 2 mg/L 6-benzylaminopurine (BAP) has regenerated shoots, but the percentage of callus producing shoots was very low (6.66 ± 2.68%). Regarding direct organogenesis from the cotyledonary node explants, the best response for shoot proliferation was observed on MS supplemented with 4 mg/L BAP (86.66 ± 12.58% of explants regenerating shoots, and an average number of 5.45 ± 0.45 shoots per explant). Low percentages of In vitro rooting of regenerated shoots were observed with different concentrations of α-naphthalene acetic acid (NAA) or indole-3-butyric acid (IBA). Nevertheless, the highest rooting percentage (13.33 ± 2.88%) was obtained on MS containing 2 mg/L NAA. These results provide new information for mass regeneration and the production of healthy seedlings, and can be applied in grapefruit improvement programs.

• #plant tissue culture and regeneration
• #plant pathogens and fungal diseases
• #plant reproductive biology
• #explant culture

Field management of Taro (Colocasia esculenta (L.) Schott) leaf blight via fungicidal spray of foliage

Tabi Kingsley Mbi, Godswill Ntsomboh Ntsefong, Libert Brice Tonfack, Emmanuel Youmbi

Journal of the Cameroon academy of sciences

Taro leaf blight (TLB) epidemic hit Cameroon for the first time in 2009. Since then, the disease is persistent and its typical devastating legacy is threatening Taro (Colocasia esculenta) in the North and South West Regions of Cameroon. This study was initiated with the objective to determine the potentials of some fungicides to control TLB. The experimental design was completely randomized with a 3x15x2 factorial, including 3 treatments: T1 (Callomil plus72WP), T2 (Mancoxyl plus 720WP) and T3, 1:1 ratio T1 + T2 all applied at concentrations of 4g/L; 15 repetitions and 2 planting seasons (dry season i.e. October 2014 – March 2015 and rainy season i.e. April-October 2015). Disease incidence and disease severity were used to evaluate the disease progression while corm yield was used to appraise the economic injury. The results revealed disease incidence of 0% during the dry season and 18.2%, 27.3% and 100%, for T1, T2 and T3 and control during rainy season respectively. Disease severity was 75% in control and only 1% for the different treatments. Corm yield in the rainy season was 17.4kg, 15.08kg, 14.27kg and 5.89kg for T1, T2, T3 and control respectively. This study suggests that TLB epidemic can effectively be managed by foliage spray with Metalaxyl containing fungicides at a weekly dosage of 4g/L. Key words: Chemical control, Colocasia esculenta, Epidemic, Phytopathology, Phytophthora colocasiae

• #pacific and southeast asian studies
• #plant pathogens and resistance
• #plant pathogens and fungal diseases
• #colocasia esculenta

Lima bean

Nono Carine Temegne, Esaïe Tsoata, Ajebesone Francis Ngome, Libert Brice Tonfack, Atabong Paul Agendia, Emmanuel Youmbi

Elsevier eBooks

• #agricultural pest management studies
• #genetic and environmental crop studies
• #legume nitrogen fixing symbiosis
• #crop

List of contributors

Atabong Paul Agendia, Seid Ahmed, A. Ajinkya, Mahalingam Angamuthu, Anjali, P.V. Aswathi and 53 more

Elsevier eBooks

• #diverse scientific and economic studies
• #legal case studies and regulations
• #human auditory perception and evaluation
• #computer science

Analysis of Orthologous SECONDARY WALL-ASSOCIATED NAC DOMAIN1 (SND1) Promotor Activity in Herbaceous and Woody Angiosperms

Libert Brice Tonfack, Steven G. Hussey, Adri Veale, Alexander A. Myburg, Eshchar Mizrachi

International Journal of Molecular Sciences

SECONDARY WALL-ASSOCIATED NAC DOMAIN1 (SND1) is a master regulator of fibre secondary wall deposition in Arabidopsis thaliana (Arabidopsis), with homologs in other angiosperms and gymnosperms. However, it is poorly understood to what extent the fibre-specific regulation of the SND1 promoter, and that of its orthologs, is conserved between diverged herbaceous and woody lineages. We performed a reciprocal reporter gene analysis of orthologous SND1 promoters from Arabidopsis (AthSND1), Eucalyptus grandis (EgrNAC61) and Populus alba × P. grandidentata (PagWND1A) relative to secondary cell wall-specific Cellulose Synthase4 (CesA4) and CesA7 promoters, in both a non-woody (Arabidopsis) and a woody (poplar) system. β-glucuronidase (GUS) reporter analysis in Arabidopsis showed that the SND1 promoter was active in vascular tissues as previously reported and showed interfascicular and xylary fibre-specific expression in inflorescence stems, while reporter constructs of the woody plant-derived promoters were partial to the (pro)cambium-phloem and protoxylem. In transgenic P. tremula × P. alba plants, all three orthologous SND1 promoters expressed the GUS reporter similarly and preferentially in developing secondary xylem, ray parenchyma and cork cambium. Ours is the first study to reciprocally test orthologous SND1 promoter specificity in herbaceous and woody species, revealing diverged regulatory functions in the herbaceous system.

• #plant gene expression analysis
• #plant molecular biology research
• #polysaccharides and plant cell walls
• #arabidopsis

Comparative Effect of Biological Fixation of Nitrogen and Chemical Fertilizer on Yield Optimization of Two Sorghum Varieties in the Western Highlands

Stéphane Martial Kamtchoum, Ibrahim Nchoutnji, Nono Carine Temegne, Libert Brice Tonfack, Lucas Fofe, Thierry Gaïtan Tchuenga Seutchueng and 4 more

Asian Journal of Agricultural and Horticultural Research

Sorghum (Sorghum bicolor (L) Moench) is a staple food in Africa, South Asia and Central America. In Cameroon, it is the main food of the population of the Sudano-Sahelian zone. Its production could decline by up to 20% by the middle of the century, due to climatic disturbances. This climatic disturbance in Cameroon has led to several consequences among which, low crop yields. The comparative effect of the biological fixation of nitrogen and chemical fertilizer on the optimization of yield of two varieties of Sorghum, was conducted from July to October at IRAD (Institute of Agricultural Research for Development) station of Foumbot. The experimental design was a complete randomized block with two factors: varieties of sorghum (V1: S35 and V2: BIOGLOR) and treatments (T0: Control, T1: 20-10-10 and T2: Sorghum / NITU beans). The collar diameter, the number of leaves and plant height were evaluated each week and yield in the end of the cropping season. As a result, treatment T1 induced very significantly (P ˂ .01) growth (shoot length, leaf and collar diameter). T1 (V1: 1.30 ± 0.11 t.ha-1, V2: 2.01 ± 0.07 t.ha-1) and T2 (V1: 1.12 ± 0.02 t.ha-1, V2: 2.15 ± 0.03 t.ha-1) showed statistically equal yields, and significantly different from T0 (V1: 0.50 ± 0.06 t.ha-1, V2: 0.55 ± 0.05 t.ha-1). The BIOGLOR variety had the highest yield (1.57 ± 0.57 t.ha-1) compared to the S35 variety (0.97 ± 0.19 t.ha-1). The treatment T2 is the recommended fertilizer system because of the higher grain yield of sorghum and its ability to protect the environment.

• #bioenergy crop production and management
• #sorghum
• #randomized block design
• #fertilizer

Production of Bean (Phaseolus vulgaris L.) under Organo-mineral Fertilization in Humid Forest Agro-Ecological Zone with Bimodal Rainfall Pattern in Cameroon

Stéphane Martial Kamtchoum, Pierre Popice Kenmogne Nuemsi, Libert Brice Tonfack, Davy Gildas Mboum Edinguele, William Ngouoko Kouahou, Emmanuel Youmbi and 1 more

Annual Research & Review in Biology

International audience

• #agriculture and rural development research
• #phaseolus
• #human fertilization
• #biology

Temporal analysis of Arabidopsis genes activated by Eucalyptus grandis NAC transcription factors associated with xylem fibre and vessel development

Madelyn I. Laubscher, Kathleen M. Brown, Libert Brice Tonfack, Alexander A. Myburg, Eshchar Mizrachi, Steven G. Hussey

Scientific Reports

Secondary cell wall (SCW) deposition in Arabidopsis is regulated among others by NAC transcription factors, where SND1 chiefly initiates xylem fibre differentiation while VND6 controls metaxylem vessel SCW development, especially programmed cell death and wall patterning. The translational relevance of Arabidopsis SCW regulation theory and the utility of characterized transcription factors as modular synthetic biology tools for improving commercial fibre crops is unclear. We investigated inter-lineage gene activation dynamics for potential fibre and vessel differentiation regulators from the widely grown hardwood Eucalyptus grandis (Myrtales). EgrNAC26, a VND6 homolog, and EgrNAC61, an SND1 homolog, were transiently expressed in Arabidopsis mesophyll protoplasts in parallel to determine early and late (i.e. 7 and 14 hours post-transfection) gene targets. Surprisingly, across the time series EgrNAC26 activated only a subset of SCW-related transcription factors and biosynthetic genes activated by EgrNAC61, specializing instead in targeting vessel-specific wall pit and programmed cell death markers. Promoters of EgrNAC26 and EgrNAC61 both induced reporter gene expression in vessels of young Arabidopsis plants, with EgrNAC61 also conferring xylem- and cork cambium-preferential expression in Populus. Our results demonstrate partial conservation, with notable exceptions, of SND1 and VND6 homologs in Eucalyptus and a first report of cork cambium expression for EgrNAC61.

• #plant gene expression analysis
• #plant molecular biology research
• #photosynthetic processes and mechanisms
• #xylem

Woody plants promoters of secondary wall-associated NAC domain homologs drive GUS and GFP activities in vascular tissues of Arabidopsis thaliana

Libert Brice Tonfack

Biological Systems Open Access

• #plant gene expression analysis
• #plant molecular biology research
• #green fluorescent protein
• #arabidopsis thaliana

Cold stress affects antioxidative response and accumulation of medicinally important withanolides in Withania somnifera (L.) Dunal

Bilal Ahmad Mir, Shabir Ahmad Mir, Jabeena Khazir, Libert Brice Tonfack, Don A. Cowan, Dhiraj Vyas and 1 more

Industrial Crops and Products

• #plant stress responses and tolerance
• #phytochemicals and medicinal plants
• #vitamin c and antioxidants research
• #withania somnifera

Oil palm (Elaeis guineensis Jacq.) improvement: pollen assessment for better conservation and germination.

Emmanuel Youmbi, Kingsley Mbi Tabi, Ngando Ebongue, Georges Frank, Libert Brice Tonfack, Godswill Ntsomboh Ntsefong

Journal of Oil Palm Research

• #oil palm production and sustainability
• #elaeis guineensis
• #palm oil
• #germination

Effect of Organic/Inorganic-Cation Balanced Fertilizers on Yield and Temporal Nutrient Allocation of Tomato Fruits under Andosol Soil Conditions in Sub-Saharan Africa

Libert Brice Tonfack, Emmanuel Youmbi, Amougou, Akoa, Anne Bernadac

HAL (Le Centre pour la Communication Scientifique Directe)

International audience

• #banana cultivation and research
• #agronomic practices and intercropping systems
• #plant physiology and cultivation studies
• #andosol

The Plant Short-Chain Dehydrogenase (SDR) superfamily: genome-wide inventory and diversification patterns

Hanane Moummou, Yvonne Kallberg, Libert Brice Tonfack, Bengt Persson, Benoı̂t van der Rest

BMC Plant Biology

BACKGROUND: Short-chain dehydrogenases/reductases (SDRs) form one of the largest and oldest NAD(P)(H) dependent oxidoreductase families. Despite a conserved 'Rossmann-fold' structure, members of the SDR superfamily exhibit low sequence similarities, which constituted a bottleneck in terms of identification. Recent classification methods, relying on hidden-Markov models (HMMs), improved identification and enabled the construction of a nomenclature. However, functional annotations of plant SDRs remain scarce. RESULTS: Wide-scale analyses were performed on ten plant genomes. The combination of hidden Markov model (HMM) based analyses and similarity searches led to the construction of an exhaustive inventory of plant SDR. With 68 to 315 members found in each analysed genome, the inventory confirmed the over-representation of SDRs in plants compared to animals, fungi and prokaryotes. The plant SDRs were first classified into three major types - 'classical', 'extended' and 'divergent' - but a minority (10% of the predicted SDRs) could not be classified into these general types ('unknown' or 'atypical' types). In a second step, we could categorize the vast majority of land plant SDRs into a set of 49 families. Out of these 49 families, 35 appeared early during evolution since they are commonly found through all the Green Lineage. Yet, some SDR families - tropinone reductase-like proteins (SDR65C), 'ABA2-like'-NAD dehydrogenase (SDR110C), 'salutaridine/menthone-reductase-like' proteins (SDR114C), 'dihydroflavonol 4-reductase'-like proteins (SDR108E) and 'isoflavone-reductase-like' (SDR460A) proteins - have undergone significant functional diversification within vascular plants since they diverged from Bryophytes. Interestingly, these diversified families are either involved in the secondary metabolism routes (terpenoids, alkaloids, phenolics) or participate in developmental processes (hormone biosynthesis or catabolism, flower development), in opposition to SDR families involved in primary metabolism which are poorly diversified. CONCLUSION: The application of HMMs to plant genomes enabled us to identify 49 families that encompass all Angiosperms ('higher plants') SDRs, each family being sufficiently conserved to enable simpler analyses based only on overall sequence similarity. The multiplicity of SDRs in plant kingdom is mainly explained by the diversification of large families involved in different secondary metabolism pathways, suggesting that the chemical diversification that accompanied the emergence of vascular plants acted as a driving force for SDR evolution.

• #plant gene expression analysis
• #enzyme structure and function
• #photosynthetic processes and mechanisms
• #biology