Background Cowpea is a grain legume of major importance in sub-Saharan Africa where it is cultivated by smallholder farmers on poor soils and production is often constrained by the parasitic weed Striga gesnerioides. Method Experiments were conducted to assess the potential of rhizobium inoculation to mitigate Striga infection and increase cowpea productivity. We infested soils with S. gesnerioides and assessed the impact of treatments combining cowpea genotypes and bradyrhizobium inoculation on Striga dynamics and cowpea yield. In total, 20 cowpea genotypes were included, of which nine were resistant to Striga and 11 were susceptible. In the first experiment these were factorially combined with three inoculation options (two bradyrhizobium strains USDA3384 and IRJ2180A, and uninoculated control) in a screen-house using potted sterile soils. Second, the same trial was repeated in the field with basal phosphorus applied at sowing and a fourth treatment of fertilizer-N (urea) included testing whether N was limiting cowpea growth. The field trial also included a separate treatment with no input that served as a negative check. Result Significant genotype x treatment interactions were observed in nodule counts, Striga attachment, emergence, and cowpea shoot growth in the screen-house. There were few nodules across all cowpea lines. Striga counts were the lowest for resistant varieties with no emerged plants. Rhizobial inoculants depressed Striga counts with consistent differences across cowpea genotypes. Inoculation with IRJ2180A performed the best against Striga attachment in resistant genotypes, and against Striga emergence in susceptible genotypes. In the field trial, cowpea grown without inputs had the least number of nodules. The genotype x treatment interaction was significant: resistant cowpea genotypes were free of emerged Striga while there was much more Striga emergence without input addition with susceptible genotypes. A significant genotype x treatment interaction was observed on cowpea grain yield. Yield response to inoculation was clearest with resistant genotypes inoculated with the strain IRJ2180A. Conclusion The integrated use of Striga-resistant cowpea lines, basal phosphorus fertilizer and elite bradyrhizobium inoculants is a promising approach to mitigate Striga infection and increase cowpea productivity.

The growth pattern and DNA yield and purity of Bulinus. globosus from River Wudil, Kano State, were investigated using standard methods. The mean ranges in mm from 7.9±2.9, 5.7±2.5, 4.8±1.8, 3.4±1.2, 1.5±0.2, 1.6 ± 0.0, 2.4 ± 0.2, 1.2 ± 0.1, 1.4 ± 0.1, 65.8 ± 1.9 and 22.2 ± 0.4 were recorded for length, width, aperture height, aperture width, height width ratio, height and aperture height ratio, height and aperture width ratio, width and aperture height ratio, aperture height and aperture width ratio, shell weight and flesh weight. About 33.7 % of weight of the snail is made up of flesh by weight. The value of “b” showed that B. globosus exhibited a negative allometric growth pattern while the correlation coefficient (r) in all the shell variables were below 1, indicating a weak correlation between the parameters. Mean DNA yield and purity were 120.03 ± 5.10 ng/µl and 1.81 ± 1.21. The DNA yield in this study is well above the minimum standard and the pure extracts are good enough for further DNA analyses.

An experiment was conducted to assess the appearance, smell, texture, pH, temperature, chemical composition and energy content of ensiled Rice offal (RO) treated with non-protein nitrogen sources and soybean meal residue in a completely randomized design. Rice offal was treated with different proportions of Urea, Poultry litter (PL) and Soybean meal residue (SBMR) and ensiled. The treatment combinations were; A (100%RO), B (100%RO + Urea), C (75%RO + 25%PL), D (50%RO + 50%PL), E (75%RO + 25%SBMR) and F (50%RO + 50%SBMR). The treatments were ensiled for 21 days in triplicates. The results showed that silages were adequately fermented with sweet aroma. The silages were acidic (4.70 – 5.80) except for treatments C and D which had pH of 7.20 and 7.00, respectively. The temperatures of the silages were significantly (P<0.05) different. The proximate composition of silages differed significantly (P<0.05), being highest for %CP, %EE and ash in treatment B. Dry matter contents were also significantly different (P<0.05) with treatment A having the highest (90.25%). Rice offal and Urea mixtures resulted in silages with highest NDF, HEM and Energy. Lowest NDF was obtained in treatment without additive (Treatment A) compared to all other treatments. Least ADF was obtained in Treatment E (75% RO + 25% SBMR). Enhancement of rice offal with urea, poultry litter and soybean meal residue has shown improvement in the silage physiochemical quality

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Cowpea is a grain legume of major importance in sub-Saharan Africa where it is cultivated by smallholder farmers on poor soils and production is often constrained by the parasitic weed Striga gesnerioides. Experiments were conducted to assess the potential of rhizobium inoculation in mitigating Striga infestation and increasing cowpea productivity. We tested under basal P application and artificial S. gesnerioides inoculation the impact of cowpea genotypes (G) (nine Striga-resistant and 11 Striga–susceptible genotypes) and bradyrhizobium inoculation (N) (two bradyrhizobium strains USDA3384 and IRJ2180A, and uninoculated control) on Striga dynamics and cowpea yield. Additional treatments included N supplied as urea (with and without), and no input (i.e., soil inherent N and P) that served as negative check. A first experiment was carried out in potted sterile soils in the screen house excluding addition of N-fertilizers. Significant G x N interactions were observed in counts of nodule (P = 0.012), Striga attachment (P < 0.0001) and emergence (P = 0.005), and cowpea shoot growth (P = 0.016). Cowpea nodulated poorly across host lines, Striga counts were the lowest for resistant varieties with no emerged plants. Rhizobial inoculants depressed Striga counts with consistent differences found across cowpea genotypes. Inoculation with IRJ2180A performed the best against Striga attachment in resistant genotypes, and its emergence in susceptible genotypes. In the field trial, nodule numbers were lowest in cowpea without inputs (P < 0.0001). The G x N interaction was significant in emerged Striga plants (P < 0.0001). Resistant genotypes were free of emerged Striga while for susceptible ones, Striga emergence was the highest without any input addition. Significant G x N interaction was observed in cowpea grain yield (P < 0.0001). Yield response to inoculation was most obvious for resistant genotypes inoculated with the strain IRJ2180A (P = 0.0043). The integrated use of Striga-resistant cowpea lines and elite bradyrhizobium inoculant under moderate application of P-based fertilizer could be a promising approach for mitigating Striga infestation and increasing productivity.