Reproductive phenology stages and their contributions to seed production of two Arachis pintoi ecotypes (CIAT 17434 and CIAT 18744) in Sudanian savanna region of Benin, West Africa

in Agricultural Science Research Journal (in press)

Flowering pattern, reproductive stage period (flowering, peg production, pod production and seed maturation) and efficiency of each stage for mature fruit production of two Arachis pintoi ecotypes (CIAT ... [more ▼]

Flowering pattern, reproductive stage period (flowering, peg production, pod production and seed maturation) and efficiency of each stage for mature fruit production of two Arachis pintoi ecotypes (CIAT 17434 and CIAT 18744) were investigated in West Africa. Plants were sown in a randomized complete block design with four replicates per ecotype. Data collected over 3 years were analyzed with ANOVA. First flowers appeared on average 26 and 45 d after sowing for CIAT 17434 and CIAT 18744, respectively. Pegs began to extend about 8 and 18 d after anthesis; pod initiation about 22 and 40 d after anthesis and seed fully matured about 85 and 120 d after anthesis, respectively. CIAT 17434 produced (2269 flowers/plant) significantly (p≤0.05) more flower than CIAT 18744 (761 flowers/plant) during 7 months flowering. Conversely, flower efficiency for peg production was significantly (p≤0.05) higher for CIAT 18744 (8.14%) than for CIAT 17434 (4.02%). From 85 to 97% of pegs produced pods for both ecotypes. This research showed clearly that the principal constraint for effective seed production in particular ecological conditions of West Africa was the quite low efficiency of flowers for pegs production. [less ▲]

Soil chemical changes following 3-year legume or grass leys in west Africa

in Tropical Grasslands (2010), 44

The influence of 4 tropical grasses (Panicum maximum, Andropogon gayanus broad- (BL) and narrow-leaf (NL) types and Pennisetum purpureum) and 6 legumes (Aeschynomene histrix, Stylosanthes fruticosa ... [more ▼]

The influence of 4 tropical grasses (Panicum maximum, Andropogon gayanus broad- (BL) and narrow-leaf (NL) types and Pennisetum purpureum) and 6 legumes (Aeschynomene histrix, Stylosanthes fruticosa, Centrosema pubescens, Mucuna pruriens var. utilis, Cajanus cajan and Leucaena leucocephala) on fertility of the top soil in the Sudanian region of Benin over 3 years was investigated. The plants were sown without fertiliser, harvested under a cut-and-carry regime and soil changes were compared with those under a natural fallow. Soil samples were collected before the study commenced and at the end of the 3-year study. These were analysed for pH, organic C, N, available P and exchangeable cations (Ca, Mg, K and Na). N, P and K contents of aerial parts were determined to estimate the exports of these elements. For the grasses, root biomass, depth and distribution were also measured. Three years after grasses and legumes were sown, the pH under the grasses (6.6-6.7) was higher than under the legumes (6.2-6.4) and C and N concentrations had declined from the initial levels. Owing to their deep rooting systems, A. gayanus BL and P. maximum, and probably C. cajan and L. leucocephala, appeared able to recycle nutrients from deeper soil layers. While these species could be used for ley pastures in savannah regions of west Africa, maintenance fertiliser applications would be required to prevent nutrient depletion under a cut-and-carry regime. Further studies to test the efficacy of farmyard manure in providing these nutrients seem warranted. [less ▲]