ABSTRACT

The mitotic chromosomal defferences of three varieties of maize (Zea mays everta, Zea mays saccharata and Zea mays turnicata) from root tips were investigated using squashing method. 0.05g of Colchicine, 3:1 ethanol-glacial acetic acid and 70% of ethanol was used for pretreatment and fixation. 1N HCl were used for hydrolysis and 2g of orcein was use for staining. the diploid number of Zea mays everta, Zea mays saccharata and Zea mays turnicatawas 2n=20 each, well spread with few overlapping chromosomes were obtained. Chromosome I with the highest value was the longest chromosome were as the shortest chromosome and the shortest chromosome is chromosome X. In Zea mays evertachromosome I, II and V was metacentrics while the rest are non-metacentrics. In Zea mays sacharata, chromosome I and II are metacentric while the rest are non-metacentrics. In Zea mays turnicata, chromosome I, II and III are metacentrics while the rest are non-metacentrics.

 TABLE OF CONTENT

Cover page i

Title page ii

Declaration iii

Certification iv

Dedication v

Acknowledgement vi

Table of content vii

List of tables ix

Abstract x

CHAPTER ONE 

1.0 Introduction 1

1.1 Justification 4

1.2 Objectives 4

CHAPTER TWO

2.0 Literature review 6

2.1 Botany of maize 6

2.2 Chromosome number and behavour 7

2.3 Genetic modification 8

2.4 Cross between Zeamays species and hybridization 9

2.4 Intra specific crosses 9

2.4.2 Interspecific crosses. 9

2.4.3 Intergeneric hybridization 10

2.5 Maize genetics, corn type races and genetic resources 11

2.6 Biotechnology intervention 14

2.7 Economic importance 14

CHAPTER THREE

3.0 Materials and method 15

3.1 Study area 15

3.2 Source of plants 15

3.3 Pretreatment and fixation 15

3.4 Hydrolysis 16

3.5 Ethical issues 16

3.6 Measurement of the chromosomal lengths 16

CHAPTER FOUR

4.0 Results 17

CHAPTER FIVE

5.0 Discussion and conclusion 22

5.1 Discussion 22

5.2 Conclusion 25

5.3 Recommendation 26

References