Evaluation of phosphorus uptake and use efficiency and nitrogen fixation potential by African clovers

• Published in: Agriculture, ecosystems & environment Vol. 65; no. 2; pp. 169 - 175
• Main Authors: Mugwira, L.M., Haque, I., Lupwayi, N.Z., Luyindula, N.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 13.10.1997; Elsevier Science
• Subjects: Adaptation to environment and cultivation conditions; Agronomy. Soil science and plant productions; application rate; Biological and medical sciences; dry matter accumulation; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; germplasm; highlands; mineral nutrition; N use efficiency; nitrogen; nitrogen fixation; Nodulation; nutrient deficiencies; nutrient uptake; P use efficiency; phosphorus; phosphorus fertilizers; roots; screening; shoots; soil fertility; species; Trifolium; use efficiency; Varietal selection. Specialized plant breeding, plant breeding aims; Vertisol; Vertisols; Ethiopia; East Africa; Africa; Nodulation; P use efficiency; N use efficiency; Trifolium; Vertisol; Soil fertility; Nutrient recovery; Entry (plant); Genotype; Plant nodule; Phosphorus fertilization; Soils; Screening; Vertisols; Absorption; Leguminosae; Dicotyledones; Angiospermae; Nitrogen fixation; Nutrient; Herbaceous plant; Spermatophyta; Fodder crop
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/S0167-8809(97)00065-0

Phosphorus deficiency is the major soil fertility problem limiting forage production in many parts of Africa. The objective of this study was to screen African Trifolium species for dry matter production, nutrient use efficiency and nitrogen fixation potential at different rates of applied P. Twenty accessions of native Ethiopian clovers were grown in a greenhouse on Vertisol at P rates of 0, 12.5, 25, 37.5 and 50 mg P kg −1 soil. The experiment was conducted in Addis Ababa, Ethiopia. In the absence of P fertilizer, there was total inhibition of nodulation in all the accessions, which virtually eliminated the potential for the clovers to fix nitrogen. Nodulation, shoot and root dry matter (DM) increased with added P. Shoot DM yields at 50 mg P kg −1 soil were 15- to 70-fold higher than those without applied P. Corresponding responses in root DM were 10- to 48-fold. Trifolium decorum accessions ILRI9682 and ILRI6264 had the highest shoot and root DM, N and P uptake, and N efficiency ratio, but the highest P efficiency ratios were found in Trifolium steudneri accession ILRI9720.