TITLE:
Phosphorus Fertilizer Rating and Rhizobia Inoculation for Improved Productivity of Cowpea in Northern Uganda
AUTHORS:
S. M. Nyamaizi, J. B. Tumuhairwe, R. Amayo, C. L. Tumuhe, E. Tereka, D. L. Nabirye, B. B. Obaa
KEYWORDS:
Phosphorus Fertilizer, Rhizobia Inoculation, Agondire, SECOW 2W, Yield
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.11 No.9,
September
29,
2020
ABSTRACT: Cowpea (Vigna unguiculata) is an important legume crop in the tropics
and subtropical regions of the world. It is mainly grown for its leaves and
grains, and to a lesser extent as a fodder crop. Cowpea is considered as the
most important food grain legume in the dry savannas of tropical Africa. This
study compared the yield of local (Agondire) and improved (SECOW 2W)
cowpea varieties grown on an Oxisol. Inorganic P at levels of 0, 10, 20, and 40
kg·ha-1 was tested
on each variety with or without rhizobia inoculation. The experiments were set
up in a randomized complete block design and replicated thrice during the short
and long rains of the 2015/2016 seasons on fifteen fields in Arua district,
northern Uganda. Agondire responded significantly (P -1)
were applied. A significant increase of 26.4% and 28.4% in grain yield of Agondire and SECOW 2W, respectively was obtained
after inoculation with rhizobia. We concluded that inoculation and P fertilizer
application increased the yield of both varieties, but with inoculation, SECOW
2W performs much better at lower P fertilizer rates than Agondire.
Therefore, we recommend growing of SECOW 2W under inoculation with 20 kg P ha-1 and an application of 40 kg P ha-1 for Agondire local cowpea variety in northern Uganda.