ABSTRACT

Low phosphorus (P) in agricultural ecosystems limits growth of bambara. Field trials were carried out at 2 P levels (0 and 35 kg/ha) to determine the variation of 12 bambara genotypes in phosphorus efficiency, identify P-efficient and responsive genotypes for cultivation in sub-optimal P environments. Genotypes differed significantly (P ≤ .05) in plant biomass, grain and biological yields due to P levels and seasonal effects. BAM002, BAM010 and BAM011 recorded high grain yields in both seasons. Phosphorus accumulation (PA) in biomass, grain and biological yields was influenced by genotype, P levels and genotype * P levels interaction. High yielding P-efficient and responsive genotypes including BAM002, BAM010 and BAM011 also had high values of phosphorus physiological efficiency index and phosphorus harvest index at low P indicating that they are P-efficient. Genotypes were classified into four and three groups based on the relationship between total PA and grain yield at low and adequate P, respectively. Moreover, genotypes were categorised into in-efficient, medium and efficient based on total index score. Principal component analysis grouped together the genotypes BAM002, BAM010 and BAM011 at both P levels. These genotypes are adapted to P-deficient soils and utilise acquired P efficiently for optimum grain production.

摘要

农业生态系统中的低磷（P）限制了班巴拉的生长。在2 P水平（0和35 kg / ha）下进行了田间试验，以确定12种bambara基因型的磷效率变化，确定在次优P环境中种植的P效率和响应型基因型。基因型差异显着（P ≤0.05）的磷水平和季节性影响导致植物生物量，谷物和生物产量增加。BAM002，BAM010和BAM011在两个季节均创纪录地高产。基因型，磷水平和基因型*磷水平之间的相互作用会影响生物量，谷物和生物产量中的磷累积量（PA）。高产磷效率和响应型基因型，包括BAM002，BAM010和BAM011在低磷条件下也具有较高的磷生理效率指数和磷收获指数，表明它们是磷有效的。根据总磷和低磷和充足磷时谷物产量之间的关系，将基因型分为四组和三组。此外，根据总指数得分将基因型分为效率低下，中等和有效。主成分分析将基因型BAM002分组在一起，BAM010和BAM011处于两个P电平。这些基因型适合缺磷的土壤，并有效利用获得的磷来优化谷物产量。