Production of banana bunchy top virus (BBTV)-free plantain plants by in vitro culture

Open Access ArticleBanana Bunchy Top Disease (BBTD) caused by the Banana Bunchy Top Virus (BBTV) is one of the most important banana diseases in the Democratic Republic of Congo. This study focused on the production of BBTV-free plantain seedlings from infected banana plants. A total of 10 suckers from the French plantain Litete (Musa AAB) and the False Horn plantain Libanga Likale (Musa AAB) with advanced BBTD symptoms were collected. Meristematic apices excised from those suckers were cultured in vitro and subcultured five times. The presence of BBTV was evaluated by the Triple-Antibody Sandwich Enzyme-linked Immunosorbent Assay (TAS-ELISA). The BBTV was confirmed in all suckers prior to in vitro culture but 73.3% of Litete plantlets and 66.6% of Libanga Likale plantlets regenerated from meristematic tissues were virus-free. This indicates that in vitro culture is a simple tool to generate BBTV-free plantains

Uptake of Conservation Agriculture Technology through Farmer Field Schools in the Democratic Republic of Congo and Mozambique

In Sub-Saharan Africa (SSA), uptake of sustainable practices such as conservation agriculture (CA) is undesirable and many studies on CA focus on a single context, and yet comprehensive approaches are demanded in the region. The study assessed the levels of usage of CA technologies in Kisangani, DR Congo and Angonia, Mozambique. Structured questionnaires were administered to 192 (384 collectively) in each study site to collect data through a multistage sampling process. Statistical analyses were used to examine possible relationships among the study parameters. The study adopted the unified theory of acceptance and use of technology theoretical framework to investigate how socioeconomic factors influence the uptake of CA as well as the Multinomial Logistic Regression model to predict the influence of farmers’ adoption. The results showed that land size used for CA was a significant predictor in both study sites. The results also showed that farmers’ intention to adopt depended on the services of vulgarisation of the technologies. The results further showed that Kisangani farmers do not use the three CA technologies at the same time, but they use crop rotation (54%). However, farmers use the three technologies (30%) simultaneously and soil cover (38%) in Angonia. For Kisangani policy makers, the results suggest that the effort to promote adoption should be based on an equal provision of extension services in all locations and the current farmer field schools (FFS) approach should be redesigned for their contextualization. For both sites, the results imply that the use of FFS should be adapted and use of farmer to farmer extension service, which can enhance the upscaling of CA to increase food security sustainably

Uptake of Conservation Agriculture Technology through Farmer Field Schools in the Democratic Republic of Congo and Mozambique

In Sub-Saharan Africa (SSA), uptake of sustainable practices such as conservation agriculture (CA) is undesirable and many studies on CA focus on a single context, and yet comprehensive approaches are demanded in the region. The study assessed the levels of usage of CA technologies in Kisangani, DR Congo and Angonia, Mozambique. Structured questionnaires were administered to 192 (384 collectively) in each study site to collect data through a multistage sampling process. Statistical analyses were used to examine possible relationships among the study parameters. The study adopted the unified theory of acceptance and use of technology theoretical framework to investigate how socioeconomic factors influence the uptake of CA as well as the Multinomial Logistic Regression model to predict the influence of farmers’ adoption. The results showed that land size used for CA was a significant predictor in both study sites. The results also showed that farmers’ intention to adopt depended on the services of vulgarisation of the technologies. The results further showed that Kisangani farmers do not use the three CA technologies at the same time, but they use crop rotation (54%). However, farmers use the three technologies (30%) simultaneously and soil cover (38%) in Angonia. For Kisangani policy makers, the results suggest that the effort to promote adoption should be based on an equal provision of extension services in all locations and the current farmer field schools (FFS) approach should be redesigned for their contextualization. For both sites, the results imply that the use of FFS should be adapted and use of farmer to farmer extension service, which can enhance the upscaling of CA to increase food security sustainably

Uptake of Conservation Agriculture Technology through Farmer Field Schools in the Democratic Republic of Congo and Mozambique

In Sub-Saharan Africa (SSA), uptake of sustainable practices such as conservation agriculture (CA) is undesirable and many studies on CA focus on a single context, and yet comprehensive approaches are demanded in the region. The study assessed the levels of usage of CA technologies in Kisangani, DR Congo and Angonia, Mozambique. Structured questionnaires were administered to 192 (384 collectively) in each study site to collect data through a multistage sampling process. Statistical analyses were used to examine possible relationships among the study parameters. The study adopted the unified theory of acceptance and use of technology theoretical framework to investigate how socioeconomic factors influence the uptake of CA as well as the Multinomial Logistic Regression model to predict the influence of farmers’ adoption. The results showed that land size used for CA was a significant predictor in both study sites. The results also showed that farmers’ intention to adopt depended on the services of vulgarisation of the technologies. The results further showed that Kisangani farmers do not use the three CA technologies at the same time, but they use crop rotation (54%). However, farmers use the three technologies (30%) simultaneously and soil cover (38%) in Angonia. For Kisangani policy makers, the results suggest that the effort to promote adoption should be based on an equal provision of extension services in all locations and the current farmer field schools (FFS) approach should be redesigned for their contextualization. For both sites, the results imply that the use of FFS should be adapted and use of farmer to farmer extension service, which can enhance the upscaling of CA to increase food security sustainably

Valorization of the essential oil from Drypetes gossweileri S. Moore (Putranjivaceae): in vitro, in vivo, and in silico nematicidal activity

The chemical composition, insect antifeedant, in vtro/in vivo nematicidal activity, phytotoxicity, and in silico nematicidal activity of the essential oil (EO) of the African medicinal plant Drypetes gossweileri were studied. Chemical analysis using GC/MS indicated that benzyl isothiocyanate (96.23%) was the major compound, followed by benzyl cyanide (1.38%). The biocidal effects of this oil were tested against insect pests and root-knot nematodes. All the insect species tested were significantly affected by the oil according to their feeding adaptations (Spodoptera littoralis and Myzus persicae were less affected than Rhopalosiphum padi) with efficient doses (EC50) of 29.4 8.3 μg/cm2, 14.744 8.3 μg/cm2, and 8.3 μg/cm2, respectively. The oil was highly effective against juveniles J2 of the nematode Meloidogyne javanica, with LC50–LC90 values of 0.007 mg/mL–0.0113 mg/mL. D. gossweileri EO at minimum lethal concentrations (MLC) and below strongly inhibited egg hatching in vitro, whereas soil treatment caused a strong suppression of nematode population, infection frequency, and multiplication rate. The EO inhibited ryegrass (Lolium perenne) germination at 0.4 mg/mL, while at 0.1 mg/mL, its effects on germination, root and leaf growth were moderate (32.4%, 8.4%, and 18.3%, respectively). The tomato (Solanum lycopersicum) germination was not affected by the EO, but the root growth was reduced (56% at 0.1 mg/mL) at a dose 10 times higher than the LD50 calculated for M. javanica J2 mortality. Molecular docking of the nematicidal effects of the oil using PyRx revealed a strong interaction between potassium chloride transporting KCC3 (PDB ID: 7D90) and benzyl cyanide at a distance of 2.20 A° with GLN C:350, followed by benzyl isothiocyanate at a distance of 2.78 A° with ARG B:294. The in vivo nematicidal effects of D. gossweileri EO on M. javanica penetration and reproduction in tomato roots further support the potential of this EO as a nematicidal agent with insect antifeedant effects, which could be used by local farmers for crop protection

Agrosystems and Mycorrhizae of Plantain (Musa AAB subgroup) in the Forest Region of Kisangani in DR Congo: Abundance and Diversity

Although DR Congo is the global centre of plantain diversity (Musa, AAB subgroup), the arbuscular mycorrhizal fungi (AMF) associated with plantain have not yet been studied in the forest region of Kisangani. This study assessed the abundance and the diversity of AMF in plantain cultivated in different agrosystems. The study addressed also the relation between AMF diversity and plantain vigour as well as the impact of soil characteristics on AMF population. Soil samples were collected from 24 plantain fields from secondary forest, fallow and homegardens. Plantains from fallow exhibited the highest mycorrhizal root colonization followed by those from forest and homegardens. But, the rhizosphere of plantains in forest had a higher amount of AMF spores than those located in fallow and in homegarden. The mycorrhizal root colonization and the AMF spore number were higher in vigorously growing plantain plants than in non-vigorously growing plantain plants. Gigasporaceae (20.4 %) has a positive correlation with plantain fields in forest and in homegardens with a strong link to organic matter, organic carbon, phosphorus and sand content. Glomeraceae (77.5%) was related to plantain fields located in fallow and in forest where the level of silt, nitrogen and hydraulic conductivity was high. Acaulosporaceae (2.1%) did not show any particular correlation with any soil parameters. This study shows that plantain located in forest and fallow agrosystems, and plantain growing vigorously harbour most mycorrhizae in the forest region of Kisangani . Keywords: Agrosystem, AMF, Kisangani, plantai

Production of banana bunchy top virus (BBTV)-free plantain plants by in vitro culture

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Assessment of the Yam Landraces (<i>Dioscorea</i> spp.) of DR Congo for Reactions to Pathological Diseases, Yield Potential, and Tuber Quality Characteristics

Yams (Dioscorea spp.) possess the potential to contribute to food security and poverty alleviation in DR Congo; however, yam production is limited by several constraints, including the lack of yam improvement programs to address challenges relating to yield improvement, resistance to foliar diseases, and post-harvest tuber quality. Identification of a superior genotype for these traits and reservoirs of genes for improvement would guide yams’ improvement. This study aims to evaluate and identify landraces with superior performance for farmers and consumers. We evaluated 191 accessions from six yam species, and significant variation in the performances was observed at p D. alata were superior for tuber oxidative browning (−0.01), D. cayenensis for high yield potential (29 t/ha), D. bulbifera for yam mosaic virus (YMV) tolerance (AUDPC = 3.88), and D. rotundata for tuber dry matter content (37%). A high genotypic and phenotypic coefficient of variation (>40) was observed for tuber yield, number of tubers per plots, tuber flesh oxidative browning, and tuber flesh texture. High broad-sense heritability estimates (>60) were similarly observed for all the assessed parameters except number of tubers per plot. Tuber size was identified as the best predictor for tuber yield (b = 2.64, p p Dioscorea species (D. alata (7); D. cayenensis (2); D. rotundata (11)). These accessions combined high yield potential, high tuber dry matter, high tolerance to YMV and YAD, and low tuber flesh oxidation. The accessions could be considered for the establishment of a yam improvement program in DR Congo