Isolation and characterization of Vigma Unguiculata nodule symbionts and evaluating cowpea yield in response to bionoculants in the Kavango region
Loading...
Date
2019
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Namibia
Abstract
The Kavango region is extensively involved in agriculture and is also known to be dominated by sandy arenosols. The bad soils in the region, which have poor nutrients and water holding capacity, combined with climate change have contributed to the reduction
in yield of most crops grown in the area. One of the aims of this study was to isolate and identify cowpea nodule symbionts from soils in the Kavango Region while the other was to determine cowpeas’ response to bio-inoculants by assessing yield of the pulse. Six different cultivars of Vigna unguiculata (cowpea) were subjected to 3 different treatments. One with chemical fertilizer, another with two Bradyrhizobium spp. bio-inoculants and a third which was a negative control with no treatment. The nodule isolates were grown on
Modified Arabinose Gluconate agar and PCR used to amplify the DNA. ITS Sequence analysis of the obtained nodule isolates from the GenBank nucleotide database revealed 5 isolates namely Bradyrhizobium americanum strain CMVU44, Bradyrhizobium vignae
strain 7-2, Bradyrhizobium kavangense strain 14-3, Bradyrhizobium ferriligni strain CCBAU 51502. The cowpeas that were subjected to the bio-inoculant treatments yielded a lager grain yield in kg per hectare as compared to the negative control and the fertilizer
treatments. The outcome of this study therefore provided the local subsistence farmers with a potential cheaper eco-friendly alternative to mineral fertilizers.
Description
A research thesis submitted in fulfillment of the requirements for the Degree of Master of Science in Microbiology
Keywords
Vigna Unguiculata, Cowpea, Arenosols, Bradyrhizobium