In tropical environments, most soybean growth studies have utilized rice husk biochar (RHB) in soil, even though it is low in nitrogen, potassium, and phosphorous. This may not give short-term agronomic performance re...In tropical environments, most soybean growth studies have utilized rice husk biochar (RHB) in soil, even though it is low in nitrogen, potassium, and phosphorous. This may not give short-term agronomic performance relative to enriched biochar. Moreover, the impact of inoculating soybean seeds with atmospheric nitrogen-fixing bacterium Bradyrhizobium japonicum on nodulation and grain yield has produced inconclusive findings in the literature. This research therefore aims to assess the effect of poultry manure (PM), poultry manure biochar (PMB) and RHB alone and in combinations on grain yield, dry shoot and root biomass of soybeans in the semi-deciduous agro-ecological zone. In addition, the effect of B. japonicum inoculated and non-inoculated soybean seeds on nodulation and grain yield was also investigated. The treatments followed a split plot design studying inoculation and non-inoculation, soil amendments (eight), and control subplot factors, respectively. The results show that the amendment of a ferric acrisol with 4 Mg∙ha−1 PM, 10 Mg∙ha−1 RHB + 2 Mg∙ha−1 PM, and 5 Mg∙ha−1 RHB + 4 Mg∙ha−1 PMB with B. japonicum inoculated seed produced significantly greater grain yield (p = 0.05). PM treatment had a significant (p B. japonicum-inoculated soybean seeds significantly (p = 0.014) increased soybean nodulation. This study suggests that RHB combined with PM or PMB provides a beneficial source of N, P, and K, resulting in improved soybean yield and nodulation in a tropical ferric acrisol.展开更多
文摘In tropical environments, most soybean growth studies have utilized rice husk biochar (RHB) in soil, even though it is low in nitrogen, potassium, and phosphorous. This may not give short-term agronomic performance relative to enriched biochar. Moreover, the impact of inoculating soybean seeds with atmospheric nitrogen-fixing bacterium Bradyrhizobium japonicum on nodulation and grain yield has produced inconclusive findings in the literature. This research therefore aims to assess the effect of poultry manure (PM), poultry manure biochar (PMB) and RHB alone and in combinations on grain yield, dry shoot and root biomass of soybeans in the semi-deciduous agro-ecological zone. In addition, the effect of B. japonicum inoculated and non-inoculated soybean seeds on nodulation and grain yield was also investigated. The treatments followed a split plot design studying inoculation and non-inoculation, soil amendments (eight), and control subplot factors, respectively. The results show that the amendment of a ferric acrisol with 4 Mg∙ha−1 PM, 10 Mg∙ha−1 RHB + 2 Mg∙ha−1 PM, and 5 Mg∙ha−1 RHB + 4 Mg∙ha−1 PMB with B. japonicum inoculated seed produced significantly greater grain yield (p = 0.05). PM treatment had a significant (p B. japonicum-inoculated soybean seeds significantly (p = 0.014) increased soybean nodulation. This study suggests that RHB combined with PM or PMB provides a beneficial source of N, P, and K, resulting in improved soybean yield and nodulation in a tropical ferric acrisol.
