Effect of two cytokinins in combination with acetic acid α-naphthalene on yams (Dioscorea spp.) genotypes’ response to in vitro morphogenesis

The effect of two growth regulator combinations was studied on the morphogenesis in vitro of 3 genotypes of yams (Kounondakou, Gnon-boya and RB 89579). Benzyl aminopurin (BAP) and zeatin (ZEAT) were tested, respectively at a concentration of 0.5 mg/l with the galzy glutamine basic medium containing naphtalene acetic acid (NAA) (0.5 mg/l). Stem fragments were used as explants. The number of stripped buds and explants having stem and roots are sampled after 2 weeks in culture. The dry matter content, the number of roots and leaves and the height of each young sprout were determined after 5 weeks in culture. The results obtained indicated that no break in leaf growth was observed on the control medium (without cytokinin) but media with BAP and zeatin presented a good plants aerial part development. A significant interaction (p < 0.05) was observed between the genotypes and the typeof cytokinin. However, the highest bud sprouting and shoot development were obtained with BAP. Thus, BAP can be considered as cytokinin having a good morphogenic aptitude when compared to zeatin for yam micropropagation.Keywords: Cytokinin, auxin, morphogenesis, yam, Beni

Genetic diversity and population structure of pigeonpea (Cajanus cajan [L.] Millspaugh) landraces grown in Benin revealed by Genotyping-By-Sequencing

Genetic diversity studies provide important details on target trait availability and its variability, for the success of breeding programs. In this study, GBS approach was used to reveal a new structuration of genetic diversity and population structure of pigeonpea in Benin. We used a total of 688 high-quality Single Nucleotide Polymorphism markers for a total of 44 pigeonpea genotypes. The distribution of SNP markers on the 11 chromosomes ranged from 14 on chromosome 5 to 133 on chromosome 2. The Polymorphism Information Content and gene diversity values were 0.30 and 0.34 respectively. The analysis of population structure revealed four clear subpopulations. The Weighted Neighbor Joining tree agreed with structure analyses by grouping the 44 genotypes into four clusters. The PCoA revealed that genotypes from subpopulations 1, 2 and 3 intermixed among themselves. The Analysis of Molecular Variance showed 7% of the total variation among genotypes while the rest of variation (93%) was within genotypes from subpopulations indicating a high gene exchange (Nm = 7.13) and low genetic differentiation (PhiPT = 0.07) between subpopulations. Subpopulation 2 presented the highest mean values of number of different alleles (Na = 1.57), number of loci with private alleles (Pa = 0.11) and the percentage of polymorphic loci (P = 57.12%). We discuss our findings and demonstrate how the genetic diversity and the population structure of this specie can be used through the Genome Wide Association Studies and Marker-Assisted Selection to enhance genetic gain in pigeonpea breeding programs in Benin

Ethnobotanical characterization of scarlet eggplant (Solanum aethiopicum L.) varieties cultivated in Benin (West Africa)

Open Access Article; Published online: 12 Jun 2021The African eggplant (Solanum aethiopicum L.) is an important traditional vegetable cultivated in tropical regions for its edible fruits. In the Benin Republic, S. aethiopicum is mainly cultivated by rural farmers for food and for its use in traditional medicine. Assessing varietal diversity, endogenous knowledge, production constraints and farmers' preference criteria are of great importance for promotion and conservation purposes. Using rural appraisal tools and methods, an ethnobotanical study was conducted in 680 households across 92 villages. A total of 60 local cultivars were collected and documented in the surveyed sites. We documented 15 farmers’ criteria for agronomic (57.88% of responses), culinary (28.51%) preference, and for economic (13.61%) aspects. Several constraints related to eggplant production in Benin were also recorded. The low market demand (27% of responses), lack of high-yielding cultivars (11.08% of responses), low fruit storability (10.67%), low productivity (9.84%), soil poverty (8.43%), susceptibility to high soil moisture (8.02%), pests (9.56%), diseases (8.45%), and drought (6.38%) appeared to be the most important constraints of the eggplant production system in Benin. In addition to synthetic pesticides, the eggplant farmers use botanical plant extracts such as extracts from Azadirachta indica (Meliaceae) and Hyptis suaveolens (Lamiaceae). It appears that eggplant production is still traditional and is of limited use in Benin. Finally, the currently collected germplasm was proposed for further evaluation using morphological and molecular markers to provide breeders with traits of interest for developing better eggplant varieties and hybrids that are suitable for local environmental conditions and production systems

White Guinea yam (Dioscorea rotundata Poir.) landraces trait profiling and setting benchmark for breeding programs in the Republic of Benin

Open Access Journal; Published online: 17 Aug 2022To meet the high demand for white Guinea yam, there is a need to develop and release improved varieties to farmers. Unfortunately, low rate of adoption of most of the improved yam varieties by both producers and consumers was observed. Information regarding agronomic characteristics and food qualities of popular white Guinea yam landraces with high market value are not available to establish minimum standards to be considered by breeding programs. To fill this gap, surveys using rural appraisal tools were carried out in 20 villages and 16 markets throughout Benin. Data on the agronomic performance suggested that for an improved variety to be adopted by Beninese farmers it should have a minimum yield of 4.16 ± 0.15 kg per mound, and average number of marketable tubers of 1.23 ± 0.05, a mean tuber length of 36.41 ± 1.22 cm, and a minimum diameter of 25.44 ± 1.16 cm. The sensorial attributes for boiled and pounded tubers of this improved variety should have minimum score of 3.16 for texture, 0.75 for softness, 3.75 for elasticity, and 1.34 for colour during the sensory evaluation. The improved variety must also have a minimum average severity score of 1.1 for yam mosaic virus disease, 1.33 for anthracnose and 1 for nematodes. Landraces Amoula, Laboko, and Djilaadja should be considered as the standard for yield, sensory attributes, and tolerance to pest and diseases while landraces Danwari, Kodjewe, Mondji, and Gnidou should be characterized as possessing good flowering and fruit setting capacities for breeding programs

Evaluation de la diversité génétique par RAPD d'un échantillon de Discorea alata d'un region du Bénin, la Sous-préfecture de Savè

No Abstract Available j. Rech. Sci. Univ. Lomé (Togo) 2002, 6(1) : 167-17