ABSTRACT

Taro leaf blight caused by Phytophora colocasiae is a disease of major importance in many region of the word where taro is grown. This study was carried out and aimed at preliminary investigation of the effects of organic soil amendment on some growth components and taro leaf blight disease severity. The soil amendments used are neem ash, cashew ash and oil palm bunch ash at rate of 50, 100 and 200g respectively. The field experiment was set up in randomized complete block design (RCBD) with three replicates. The result of the effect of the soil amendment on the growth components showed significant difference P<0.05 on most of the components investigated. The analysis of the variance on leaf area showed that there was significant difference (p>0.05) due to the treatment. There was significant difference (p<0.05) on the number of leaf for each plant stand. The mean values range from 3.232 – 2.879. A very highly significant difference (p<0.05) was observed on the plant girth due to the soil amendment. The plant height was highly significance at (p<0.05). The soil amendment significantly affected the plant height. The result obtained on the disease severity indicated that the various soil amendment showed on significance difference (p>0.05) following analysis of variance. This study showed that the different organic soil amendments significantly influence the growth components investigated. However, this study also revealed that the soil amendments increase the disease severity in C50, C100, and O200 respectively.

TABLE OF CONTENTS

Cover page i

Title page ii

Certification iii

Declaration iv

Dedication v

Acknowledgement vi

Table of content vii

List of tables viii

Abstract ix

CHAPTER ONE:

1.1 Introduction 1

1.2 Aim of the Study 3

1.3 Objectives of Study 3

CHAPTER TWO

2.0 Literature Review 4

2.1 Origin and Distribution of Taro 4

2.2 Botany of Taro 5

2.3 Uses of Taro 6

2.4 Ecology of Taro 6

2.5 Brief Overview of Plant Nutrition 7

2.6 Effect of Number and Size of Leaf On Crop On Crop Growth And Yield 8

2.7 Organic Manures 8

2.8 Effect of Sucking on Yield 9

2.9 Factors Affecting Cooking of Taro Corm 10

2.10 History of Taro Leaf Blight Epidermic and Impacts 11

2.11 Disease Symptoms 13

2.12 Biology of the Pathogen 14

2.12.1 Host Range 14

2.12.2 Life Cycle 15

2.12.3 Infection Process and Conditions 16

2.12.4 Disease Epidermology 16

2.13 Disease Management Strategics 18

2.13.1 Cultural and Biological Control 18

2.13.2 Chemical Control 18

2.14 Resistant Cultivers and Genetic Resources 19

2.15 Breeding of Resistance to Taro Leaf Blight 22

CHAPTER THREE

3.0 Materials and Methods 24

3.1 Study Area 24

3.2 Collection of Planting Materials 24

3.3 Experimental Design 24

3.4 Land Preparation 24

3.5 Planting 25

3.6 Soil Amendment 25

3.7 Taro Leaf Blight Pathogen (TLB) 25

3.7.1 Fertilization and Soil Amendments 25

3.7.2 Inoculation 25

3.7.3 Weeding 26

3.8 Collection of Data 26

3.9 Data Analysis 26

CHAPTER FOUR

4.1 RESULTS 27

CHAPTER FIVE

Discussion and Conclusion 30

5.1 Effect of the Treatment on the Growth Parameters on Taro 30

5.2 Conclusion 32

REFERENCES