A B S T R A C TStudies on the effect of biochar and poultry manure on soil properties and radish productivity is rare, hence, field experiments were conducted over two years, 2015 and 2016, to evaluate the effects of biochar (B) and poultry manure (PM) on soil properties, leaf nutrient concentrations and root yield of radish (Raphanus sativus L.). Each year, the experiment consisted of 3 × 3 factorial combinations of biochar (0, 25 and 50 t ha −1 ) and poultry manure (0, 2.5 and 5.0 t ha −1 ). Application of B and PM alone, and in combination, improved soil physical and chemical properties, leaf nutrient concentrations and yield components of radish. In 2016, the application of B alone increased the soil pH and concentrations of organic matter, N, P, K, Ca and Mg, as well as leaf nutrient concentrations and yield of radish, but in 2015 it only increased soil pH and organic matter and not leaf nutrient concentrations and yield. In both years, the application of B significantly influenced the root length of the radish. In both years, there was a significant interaction effect of biochar and poultry manure (B × PM) and this was attributed to the ability of the B to increase the efficiency of the utilization of the nutrients in the PM. The combination of 50 t ha −1 B and 5 t ha −1 PM (B 50 + PM 5 ) resulted in the highest radish yield. Averaged over the two years, (B 50 + PM 5 ) increased the root weight of radish by 192, 250 and 257% compared with biochar alone at 50 t ha −1 , biochar alone at 25 t ha −1 and no application of B or PM (control). Therefore, for a short season crop like radish the expected benefit of the biochar alone without the addition of poultry manure may not be achieved within the first year. + , and NO 3 − in animal manure (Steiner Notes: Values followed by the same letters, within column, are not significantly different at p < 0.05 according to Duncan's multiple range test. * =significant at 5% level of probability; ns = not significant at 5% level of probability; B = Biochar; PM = Poultry manure.

Use of organic manures to meet the nutrient requirement of crop would be an inevitable practice in the years to come for sustainable agriculture since organic manures generally improve the soil physical, chemical and biological properties. Hence, field experiments were carried out in 2017 and 2018 to compare the impact of different organic manures and NPK fertilizer on soil properties, growth, yield, proximate and mineral contents of okra (Abelmoschus esculentus L.). The treatments each year 2017 and 2018 consisted of: rabbit manure, cow dung, poultry manure, green manure [Mexican sunflower (Tithonia diversifolia Asteraceae)], pig manure, NPK 15-15-15 fertilizer applied at 120 kg N ha−1 and a control (no manure/inorganic fertilizer). The seven treatments were laid out in a randomized complete block design with three replication. Organic manures and NPK fertilizer increased the soil organic matter (OM), N, P, K, Ca and Mg (NPK fertilizer did not increase OM, Ca and Mg significantly), growth, yield, minerals, protein, ash, carbohydrate and mucilage contents of okra fruit as compared with control. Organic manures improved okra yield compared with NPK fertilizer. Okra growth and yield parameters were significantly higher in 2018 compared with 2017. Control, rabbit manure, cow dung, poultry manure, green manure, pig manure and NPK fertilizer in 2018 increased the pod yield of okra by 9.7%, 35.3%, 57.9%, 36.2%, 39.2%, 45.5% and 3.2%, respectively compare with the same treatment in 2017. Amongst various organic manures, poultry manure produced significantly higher plant growth, yield, mineral and proximate composition of okra because of its high soil chemical properties which could be related to its lowest C: N ratio, lignin and lignin: N ratio. Results also showed that okra grown during high intensity rainfall has higher yield but with reduced quality except its mucilage content. Therefore, planting of okra with poultry manure under moderate rainfall will enhance the health benefit from the fruit, however, those that desire its mucilage content planting during high rainfall is recommended.

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a b s t r a c tThe type of materials used as mulch and season of application may determine its impact on soil physical and chemical properties and crop yield. Hence, field experiments were carried out during 2015 (dry) and 2016 (wet) cropping seasons to determine the effect of various mulch materials on soil properties, leaf nutrient composition, yield and growth of okra (Abelmoschus esculentus (L.) Moench). The experiment consisted of four mulch materials (a) Pueraria phaseoloides, (b) Mucuna pruriens, (c) Pennisetum purpureum), (d) Panicum maximum and a control (no mulch application). The five treatments were arranged in a randomized complete block design with four replications. Application of mulch reduced bulk density, soil temperature and increased porosity, soil moisture content, pH, OM, soil and leaf N, P, K, Ca, Mg, pod yield and growth of okra compared with the control. Legume mulch materials (LMM) (Pueraria and Mucuna) produced higher values of OM, N, P, K, Ca and Mg compared with grass mulch materials (GMM) (Pennisetum and Panicum) in both seasons. GMM significantly (p ≤ 0.05) reduced bulk density and soil temperature and increased porosity and moisture content compared with the LMM in 2015. The correlation coefficient showed that the yield of okra in 2015 was dependent on soil physical properties while the yield in 2016 was dependent on soil chemical properties. GMM in 2015 produced 49% and 158% higher pod yield compared with LMM and the control, respectively. LMM increased the pod yield of okra in 2016 by 56% and 122% compared with GMM and the control, respectively. Therefore the use of grass materials as mulch in the dry season and the use of legume mulches during the wet season maximized yields.