ISOLATION OF FUNGI ASSOCIATED WITH ROT ONION BULBS

ABSTRACT

This study was conducted to examine the fungi present in spoilt onion bulb. Five different sample of spoilt onion bulb were blended together and suspended in sterilized distilled water which was used to inoculate Sabouraud dextrose agar (SDA). Four different fungi were isolated from the sample and the morphological characteristics shows that the isolate belong to the following genera: Alternaria sp., Aspergillius sp., Penicillium sp., and Rhizopus sp. These fungi may have been responsible for the spoilage of onion bulb sample and therefore the need to store the onion bulb in dry well ventilated stores which will reduce growth and development of fungal pathogens and minimize storage rots.

TABLE OF CONTENTS
Title                                            i
Certification                                    ii
Dedication                                    iii
Acknowledgement                                iv
Table of contents                                v
Abstract                                         vii

CHAPTER ONE
1.0     Introduction                                    1
1.1     Background of the study                            1
1.2     Statement of problem                            4
1.3     Significance of the study                            5
1.4     Scope of the study                                5
1.5     Objective of the study                            6

CHAPTER TWO
2.0    Literature review                                7
2.1    Description of onions bulbs (Allium cepa)                7
2.2    Scientific classification of onions                    10
2.3    Nutritional values of onions                        12
2.4    Medicinal uses of onion                            13
2.5    Pathogens and pests of onion bulb                    15
2.6    Fungi                                        16
2.7    Mold                                         18

CHAPTER THREE
3.0    Material and method                                21
3.1    Collection of samples                            21
3.2    Media preparation                                21
3.3    Isolation of rot inducing fungi from the sample            22
3.5    Identification of fungi                            22

CHAPTER FOUR
4.0    Results                                        23
4.1    Isolation and identification of fungi                    23

CHAPTER FIVE
5.0    Discussion, conclusion and recommendations            24
5.1    Discussion                                     24
5.2     Conclusion                                     25
5.3    Recommendations                                26
References                                    27