CHAPTER ONE: INTRODUCTION                                                                                               1

1.1       Background to the Study                                                                                           1

1.2       Statement of the Problem                                                                                           3

1.3       Aim and Objectives                                                                                                    3

1.4       Justification of the Study                                                                                           3

CHAPTER TWO: LITERATURE REVIEW                                                                                    4

2.1       Rank Scientific Name and Common Name of Zea mays L.                                      4

2.2       General Description of Zea mays L.                                                                           5

2.3       Nutritional value of Maize                                                                                          9

2.4       Phytochemical value of Maize                                                                                    10

2.5       Health Benefits of Maize                                                                                            12

2.6       Glyphosate Herbicide and Its Effect on Soil and Plant                                             14

2.7       Vermicompost (VC)                                                                                                   17

2.8       Compost from Earthworm                                                                                          17

2.9       Chemical Constitutes of Vermicompost Tea (VCT)                                                   18

2.10     Microbial Constituents of Vermicompost Tea                                                            19

2.11     Plant Growth Effects of Vermicompost Tea                                                              20

2.12     Effect of Vermicompost on Soil Fertility                                                                   22

2.13     Advantages and Disadvantages of Glyphosate Based Herbicide on 

            Plant                                                                                                                            25

2.13.1  Advantages of Glyphosate Based Herbicides (GBHs) on Plant                                25

2.13.2  Disadvantages of Glyphosate Based Herbicide on Plant                                           26

CHAPTER THREE                                                                                                                32

3.0       Materials and Methods                                                                                               32

3.1       Experimental Set Up                                                                                                   32

3.1.2    Collection and Contamination of Earthworm CAST                                                 32

3.2       Planting Experiment                                                                                                   33

3.2.1    Preparing the Land for Planting                                                                                 33

3.3       Plant Measurement for Growth Performance                                                             33

3.4       Statistical Method                                                                                                       33

CHAPTER FOUR: RESULTS                                                                                              34

4.1       Physical Parameters Of Vermicast Tea                                                                       34

4.2       Level of heavy metals in cast produced by the three earthworm 

            species exposed to GBH exposure versus non-exposed                                             36

4.3       Level of minerals in cast produced by the three earthworm species 

            exposed to GBH exposure versus non-exposed                                                         38

CHAPTER FIVE: DISCUSSION                                                                                         43

5.1       Discussion                                                                                                                   43

CHAPTER SIX                                                                                                                      47

Conclusion                                                                                                                              47

REFERENCES                                                                                                                      48

APPENDIX                                                                                                                            54

LIST OF TABLES

TABLE          TITLE                                                                                                PAGES

1          Physico-chemical properties of earthworm cast and soil                                            35

2          Heavy metals in earthworm cast and soil                                                                   37

3          Minerals composition of earthworm cast and soil                                                      39

4          Levels of antioxidant enzymes in the roots of Zea mays planted with wormcast 

            contaminated with a glyphosate-based herbicide                                                       42 

Earthworm cast has been reported to enhance the growth and development of crop plants. Although, studies have indicated toxicity of glyphosate-based herbicides (GBHs) on some earthworm species. It also remains, unknown if the cast contaminated with GBH can still retain its agricultural benefits. The aim of this study was to determine the antioxidant defense profile in the root of Zea mays planted with wormcast contaminated with glyphosate based herbicide. Casts from three species of earthworm (Eudrillus euginea, Alma millsoni, Lubridicus rubellus) were collected from the unpolluted arable land of the University farm. A portion was sprayed with 7.2 ml and 14.4 ml of glyphosate-based Roundup herbicide separately. Both the contaminated and uncontaminated earthworm cast as well as soil samples were analysed for physical, chemical and minerals compositions. Leaf height, leaf breath, stem height, stem girth, leaf number and plant height of the Zea mays were the growth parameters measured. Plant height was measured with tape rule and the stem width was measured with venier caliper measurement were carried done two weeks after planting and this lasted for two weeks. Results showed that there was no significant difference (p > 0.05) in most of the chemical properties of the sprayed and unsprayed vermicast tea of Alma millsonii, Eudrillus eugeniae and Libyodrillus violaceous. There was significant difference in the level of heavy metals in cast produced by the three species exposed to GBH exposure and non-exposed. However, Pb, Cr, Cd and Ni was not detected in most of the cast produce by the three earthworm species. There was no significant difference in the level of minerals in cast produced by the three species exposed to GBH exposure and non-exposed. It was concluded in this study that despite the higher concentrations of nutrients in the casts produced by earthworm species exposed to a GBH, they could not produce antioxidant defense in root of zea mays. On the other hand, the casts produced by earthworms unexposed to GBH were able to enhance produce antioxidants defense in root of zea maize. Thus wormcast could be used as an agent for increase the antioxidant defense of plants.