Mutagenic Effect Of Different X-Ray Doses On Growth Of Capsicum annum L

ABSTRACT

This study investigated the mutagenic effect of x-ray on growth of pepper (Capsicum annum) of three different varieties of pepper- Langa langa, (World bitter and California wonder). The experiment was carried out in the screen house of Michael Okpara University of Agriculture, Umudike, Umuahia, Abia State, Nigeria, and in the research field of National Plant, Soil and Water Laboratory, Umudike. The experiment was carried out using seeds collected from National Agricultural Seed Council (NASC), Umudike. The experiment was laid out as Randomised Complete Block Design (RCBD) replicated three times. Parameters evaluated include root length, shoot height, number of leaves, germination percentage, leaf area and plant girth. The x-ray irradiation doses used were 1 Mgy, 2 Mgy, 4 Mgy, 6 Mgy and 8 Mgy. From the result, it was observed that World bitter produced its highest germination percentage (59%), highest number of leaves (3.4 mean value), highest plant girth (1.9 mm) and highest root length (2.4 mm) all at 6 Mgy x-ray radiation dose while Langa langa produced the highest number of leaves at 1 Mgy (3.4 mean value) and 4 Mgy x-ray radiation dose (at 2.7 mean value). Valencia sweet pepper produced the least percentage germination, least number of leaves and least root length. This evaluation suggests that the breeders could use these observations in their breeding selection.

TABLE OF CONTENTS

Title page                                                                                                        ﾿ i

Declaration ﾿ ii

Certification ﾿ iii

Dedication ﾿ iv

Acknowledgements ﾿ v

Table of Contents ﾿ vi

List of Tables ﾿ viii 

List of Figures ﾿ ix

List of Plates ﾿ x

Abstract ﾿ xi

CHAPTER ONE: INTRODUCTION ﾿

1.1 ﾿ Background of the Study ﾿ 1

1.2 ﾿ Justification of the Study ﾿ 4

1.3 ﾿ Aim of the Study ﾿ 4

1.4      ﾿ Objectives of the Study ﾿ 4

CHAPTER TWO: LITERATURE REVIEW

2.1 ﾿ Mutation ﾿ 5

2.1.1 ﾿ Types of Mutation ﾿ 5

2.1.2 ﾿ Induced Mutation ﾿ 6

2.1.3 ﾿ Physical Mutagens ﾿ 6

2.2 ﾿ X-rays ﾿ 7

2.3 ﾿ Radiation Units ﾿ 8

2.4 ﾿ Chemical Mutagens ﾿ 8

2.4.1 ﾿ Spontaneous Mutation ﾿ 9

2.4.2 ﾿ Mutation Rate ﾿ 9

2.4.3 ﾿ Effect of Mutation on the Phenotype ﾿ 10

2.4.4 ﾿ How Does a Mutation Act? ﾿ 11

2.4.5 ﾿ Significance of Mutation ﾿ 11

2.4.5.1 Application in Plant Breeding ﾿ 11

2.4.5.2 ﾿ Mutation Breeding of Pepper ﾿ 12

2.4.5.3 ﾿ Uses of Pepper ﾿ 13

2.4.5.4 ﾿ Medicinal Uses of Pepper ﾿ 13

2.4.5.5 ﾿ Role in Evolution ﾿ 14

CHAPTER THREE: MATERIALS AND METHODS

3.1 ﾿ Study Area ﾿ 15

3.2 ﾿ Design of the Experiment ﾿ 15

3.3 ﾿ Collection of Samples ﾿ 15

3.4 ﾿ Seed Treatment ﾿ 16

3.5 ﾿ Dosimetry ﾿ 16

3.6 ﾿ Treatment ﾿ 16

3.7 ﾿ Measurement Parameters                                              ﾿ 16

3.7.1 ﾿ Germination Percentage                                  ﾿           ﾿ 17

3.7.2 ﾿ Plant Height                                                  ﾿                     ﾿ 17

3.7.3 ﾿ Root Length                                                              ﾿ 17                              

3.8 ﾿ Statistical Analysis ﾿ 17

CHAPTER FOUR: RESULTS ﾿             ﾿ 18

CHAPTER FIVE

5.1 ﾿ Discussion ﾿ 29

5.2 ﾿ Discussion ﾿ 30

References ﾿ 31