Nitrogen assimilation in young African yam bean plant in a ferruginous ultisol

Abstract

The aim of the study was to investigate nitrogen assimilation in young African yam bean (Sphenostylis stenocarpa) plant in a ferruginous ultisol. Twenty (20) kg of the sun-dried top soil was measured into thirty (30) large experimental bags and arranged in the experimental farm following a completely randomized design. The ferruginous status of the soil was ascertained upon soil chemical analysis to content to be 1011.92 mg/kg. Four seeds each of nine accessions of viable African yam bean (TSs-141, TSs-142, TSs-143, TSs-144, TSs-145, TSs-146, TSs-147, TSs-148, and TSs-149) were sown in each bag. The experimental set up was monitored for 24 weeks and samples were taken to the laboratory for analyses while morphological growth parameters were measured onsite. The shoot of TSs-147 accession was lengthiest (49.84 cm) while 31.34 cm was the least measured for TSs 141. With regards to nitrogen content, TSs-147 (2.57 % N) and TSs-149 (2.52 % N) maintained higher nitrogen levels in their leaves than TSs-142 (1.96 % N) and TSs-145 (1.93 % N). With significantly higher NR activity as well as chlorophyll content, it is expected that TSs-147 would comparatively thrive better among the selected accessions if cultivated in areas with significant Fe concentration.