Influence of Phosphorus Sources on Soybean Growth and Nodulation in Typic Plinthustalfs of Southern Guinea Savanna, Nigeria.

Abstract

Phosphorus is one of the most limiting plant nutrient in tropical soils. A pot trial was conducted using soils from three
locations (Maikunkele, Maitunbi and Gidan Kwanu) of Bosso local government area in Minna, Niger State, Nigeria. The
trial was set up in the screen house of the School of Agriculture and Agricultural Technology, Soil Science and Land
Management, Federal University of Technology, Minna, in the Southern Guinea Savanna of Nigeria. The treatments
include three phosphorus sources; inorganic phosphorus as single superphosphate (SSP), organic phosphorus as bone
meal (BM) and bio–phosphorus as “Glomus intaradices” (Arbuscular Mycorrhizal Fungi) and a control, laid out in a
Completely Randomized Design (CRD), replicated three times. The observed parameters includes plant height, number of
branches, number of leaves, number of nodule, nodule and root dry weights. Analysis of variance was done using Genstat
statistical package. Significant means were further separated using Least Significant Difference (LSD) at P < 0.05,
soybean (TGX 1988-5F) was the test crop. The results shows that soybean responded to the treatments positively. The
observed parameters (plant height, number of branches, number of leaves, number of nodule, nodule and root dry weights)
were all enhanced as a result of the various sources of phosphorus applied as compared to the control. The application of
inorganic–P (SSP), organic-P and bio–P (AMF) were significant at the three locations for leaf area, shoot weight (except at
Gidan Kwanu where only the inorganic-P (SSP) was significant for shoot weight). The nodule number was also significant
at Maikunkele and Maitunbi with the use of inorganic-P (SSP) and bio-P (AMF), while the nodule and root dry weight
recorded substantial increase in weight to the application of the P-sources as compared to the control. Hence, the
application of the various sources of phosphorus is worthwhile for soybean growth and grain yield improvement on Typic
Plinthustalfs soil in the study area.