Effects of Rabbit Manure and Sodium Enhanced NPK Fertiliser on Soil Phosphorus,  Yield, and Phosphorus Content of Green Amaranth

F.T. Olatoberu; M.K.  Idowu; F. A. Oladipupo; B.O.  Oyeyemi; D.T.  Ogunjinmi

Authors

Olatoberu, F.T. Department of Soil Science and Land Resources Management, Obafemi Awolowo University, Ile Ife, Osun State, Nigeria
Idowu, M.K. Department of Soil Science and Land Resources Management, Obafemi Awolowo University, Ile Ife, Osun State, Nigeria
F. A Oladipupo Department of Soil Science and Land Resources Management, Obafemi Awolowo University, Ile Ife, Osun State, Nigeria
Oyeyemi, B.O. Department of Soil Science and Land Resources Management, Obafemi Awolowo University, Ile Ife, Osun State, Nigeria
Ogunjinmi, D.T. Department of Soil Science and Land Resources Management, Obafemi Awolowo University, Ile Ife, Osun State, Nigeria

Keywords:

Rabbit manure Sodium-enhanced NPK Soil phosphorus Green amaranth Amaranthus viridis

Abstract

Integrated nutrient management is increasingly promoted as a sustainable
method for improving soil fertility and vegetable productivity in tropical
agro-ecosystems. This study evaluated the combined effects of rabbit
manure (RM) and sodium-enhanced NPK fertilizer on soil phosphorus
availability, yield, moisture content, and phosphorus content of green
amaranth (Amaranthus viridis). A field experiment was conducted using a
randomized complete block design with five treatments (control, NPK +
Mg, NPK + Mg + RM, NPK + Mg +Na, and NPK + Mg + RM + Na)
replicated thrice resulting into 15 experimental plots. Fertilizer was applied
at 60 kg NPK ha⁻¹, 40 kg Mg ha⁻¹, 4 kg Na ha⁻¹, and at 5 tons rabbit manure
ha⁻¹. Results showed that integrated application of NPK + Mg + RM + Na
had the highest fresh shoot weight of green amaranth, which was 131%
higher than NPK + Mg + RM. However, NPK + Na + Mg had the highest
leaves P concentrations which was 34% higher than NPK + Mg + RM + Na.
Soil available phosphorus after harvest was significantly improved under
Na-containing treatments (NPK + Na + Mg, and NPK + Mg + RM + Na).
The study concluded that integrating rabbit manure with sodium-enhanced
NPK fertilizer improves soil phosphorus availability, green amaranth fresh
shoot weight and dry matter yield.