OSHO TOYIN BEATRICE

Agriculture

At the Agriculture department office

Appointment on Visitation important

Topic: Screening For Mosaic Disease Resistance And Hydrogen Cyanide (HCN) Content In Cassava At Different Ages

Description:

1. Introduction
   Cassava (Manihot esculenta Crantz) is a staple food for more than 800 million people in Africa. Although the crop can adapt and grow well in different environments, its productivity varies in genotypes and from one environment to another. This variability is due to inherent properties of genotype, environment conditions and genotype-by-environment (G×E) interaction. Among environment factors, cassava mosaic disease (CMD) caused by cassava mosaic geminiviruses, is considered the most important factor reducing cassava yields in many parts of Africa.
   Cassava has developed defense mechanisms including the biosynthesis of cyanogenic glucosides (CG) against the attack of herbivores and pathogens on its plant tissue; however, the biosynthesis of this CG in the cassava plant tissue has detrimental effect on humans when consumed. The level of CGs in cassava vary based on factors such as the variety, climatic conditions, soil type, age and part of the plant. Therefore, determining the HCN content in cassava at different ages at different locations in this study will help elucidate the rate and trend of accumulation of HCN in cassava. Screening of cassava genotypes for mosaic disease resistance will help in developing varieties with broad resistance to CMD.
   Methodology
   Ten cassava genotypes including checks susceptible to CMD will be used for the study. The study will be carried out using a factorial experiment fitted into randomized complete block design with three (3) replicates in three (3) locations.
   Data will be collected on growth and yield characters; and will be subjected to analysis of variance, correlation analysis and cluster analysis using SAS 9.4 version software.
   Expected results
   The relationships among plant ages, whitefly and HCN content in the roots and leaves of cassava will be determined. Genetic variation for HCN content and CMD resistance among the genotypes across locations will be known.
   
   
   

#	Certificate	School	Year
1.	M.Sc (Plant Breeding)	Pan African University, Institute for Life and Earth Sciences (including Health and Agriculture)	2018

Genotypic variation in nodulation and grain yield of cowpea (Vigna unguiculata L. Walp) mini core collection

A decline in nitrogen status of soils is experienced in many parts of the world, especially West Africa. However, cowpea (Vigna unguiculata L. Walp) has the ability to fix atmospheric nitrogen through symbiosis with nodule bacteria (Bradyrhizobium spp.) to improve production and maintain soil fertility. The cowpea mini core collections were recently composed at International Institute of Tropical Agriculture (IITA) and there is need for screening of the genotypes for nodulation to determine their nitrogen fixation potential. An understanding of the nitrogen fixation potential and yield of cowpea genotypes will facilitate the development of cowpea varieties with high productivity. The objective of this study was therefore to evaluate cowpea genotypes for nitrogen fixing and yield potential.
A total of 200 cowpea lines selected from among individuals in the mini core collection at IITA, Ibadan were grown in the glass house at IITA using a completely randomised design with three replicates. Data were collected on number of nodules, shoot nitrogen content, total plant biomass, pods per plant and grain yield. Analysis of variance, cluster analysis and linear correlation were carried out on all the variables and significantly different means were separated using LSD at 5%.
Significant genetic variability was observed among the cowpea genotypes used in this study. TVu16521 and TVu8673 were the top nodulating genotypes. The highest value for pods/plant was observed in TVu3156. The highest yield value was observed in TVu3156. The genotypes were grouped into seven clusters and four outliers that were fused into clusters at much higher distances. Positive correlation was observed between number of nodules and each of shoot dry weight and root dry weight.
The broad genetic variation observed among the cowpea lines evaluated in this study for nodulation, growth and yield variables can be explored to improve cowpea further for the desirable traits.

OSHO TOYIN is a Assistant Lecturer at the Department of Agriculture

OSHO has a M.Sc in Plant Breeding from Pan African University, Institute for Life and Earth Sciences (including Health and Agriculture)