DEVELOPMENT OF AN INTEGRATED PEST MANAGEMENT STRATEGY FOR THE CONTROL OF Maruca vitrata ON COWPEA IN KEBBI STATE OF NIGERIA MAIKAI ABDULLAHI MURNA (000441065) A thesis submitted in partial fulfilment of the requirements of the University of Greenwich for the Degree of Doctor of Philosophy This research programme was carried out in Zuru Local Government Area of Kebbi State of Nigeria June 2013 i DEDICATION This thesis work is dedicated to my parents ii ABSTRACT The study was undertaken with the objective of developing an IPM control strategy against M. vitrata in cowpea which will replace the existing use of calendar based application of broad spectrum chemical insecticide (Mixture of 30g cypermethrin and 250g dimethoate) in Kebbi State of Nigeria. The study initially made use of a survey backed up by focus group interviews to gather information on the types of farmers’ cowpea cultivation practices, their perceptions on pests and pesticides and the economics of cowpea cultivation with the aim of incorporating those practices that were found to be IPM compatible in the strategy developed. The result showed that most farmers were small scale growers who inappropriately used chemical insecticides due to lack of knowledge of other alternatives. Farmers had good scouting ability as demonstrated by their knowledge of field insect pests of cowpea, the nature of their feeding habit and magnitude of damage due to these insect pests. Cowpea cultivation in Zuru is profitable, labour and insecticides costs were the major profit limiting factors in cowpea cultivation. Therefore, an on-station trial was conducted which initially focused on the evaluation of four potential IPM components for their suitability as control tools against M. vitrata using two cowpea varieties [Danzafi (local) and improved Kanannado (IT89KD-245-1)]. The result showed that neem (nke) at 5% concentration was as effective as chemical insecticide (mixture of cypermethrin and dimethoate) in terms of reducing larval infestation/damage, pods and seeds damage as well as increasing yield of cowpea. In the next season another on-station trial was conducted to validate use of nke on scouting basis as an IPM system for the management of M. vitrata using the same cowpea varieties. The result showed that, the scouting based nke application had significantly higher larval infestation/damage which significantly lowered yield in comparison with the calendar based insecticide application. However,; the highest cost benefit ratio was sustained by the scouting based nke application. During the third season on-farm trial, although nke on scouting based application had significantly higher larval infestation/damage compared to calendar based chemical insecticide application yield was similar, indicating that it was not affected. The application of nke on scouting basis did not affect the abundance of the natural enemies. It was therefore concluded that nke application on scouting basis has the potential as an IPM control strategy against M. vitrata in cowpea. iii ACKNOWLEDGEMENTS The researcher acknowledged the contributions made by Prof. Alan Cork former first supervisor and the present first and second supervisors Dr Rory Hillocks and Dr. Tim Chancellor for their supervision, direction, support and contributions in making this work a reality. The contribution of the statistician Dr. Stephen Young in advising the analysis of the data gathered in the study is appreciated. The contribution of the management of College of Agriculture Zuru and Science laboratory staff is acknowledged. The contributions of the volunteering IPM farmers, Research assistant Jonathan Clement and Mohammad Sirajo and the Agricultural Extension officers of Manga, Zuru and Dabai districts are also acknowledged. iv DECLARATIONS I certify that this work has not been accepted in substance for any degree, and is not concurrently being submitted for any degree other than that Doctor of Philosophy being studied at the University of Greenwich. I also declare that this work is the result of my own investigations except where otherwise identified by references and that I have not plagiarised the work of others. Candidate Maikai Abdullahi Murna Date 17-05-2013 First supervisor Date Dr Rory Hillocks Second supervisor Date Dr Tim Chancellor v TABLE OF CONTENTS TITLE PAGE………………………………………………. i DEDICATION……………………………………………. ii ABSTRACT……………………………………………… iii ACKNOWLEDGEMENT…………………………………… iv DECLARATION…………………………………………… v TABLE OF CONTENTS………………………………… vi LIST OF TABLES………………………………………… xiii LIST OF FIGURES AND PLATES……………………… xvi LIST OF SYMBOLS AND ABBREVIATIONS………….. xix 1 INTRODUCTION AND OBJECTIVES......................... 1 1.1 INTRODUCTION………………………………………….. 1 1.2 ABOUT THE STUDY AREA……………………………….. 2 1.3 STATEMENT OF THE PROBLEM…………………………. 3 1.4 OBJECTIVES OF THE STUDY……………………………… 4 1.5 SIGNIFICANCE AND SCOPE OF THE STUDY...................... 4 1.6 RESEARCH QUESTIONS AND HYPOTHESES................... 5 1.6.1 Hypotheses.................................................................................................... 5 1.6.2 Additional Research Questions................................................................. 5 2 LITERATURE REVIEW...................................................... 6 2.1 BIOLOGY OF MARUCA vitrata (Fabricius) LEPIDOPTERA: Pyralidae................................................................................. 6 2.1.1 Taxonomy..................................................................................................... 6 2.1.2 Distribution.................................................................................................. 6 2.1.3 Morphology................................................................................................. 7 2.1.4 Life Cycle..................................................................................................... 8 2.1.5 Types of Damage Caused............................................................................ 8 2.2 METHODS OF M. vitrata LARVAE INFESTATION 10 vi ASSESSMENT IN COWPEA.................................................. 2.3 ASSESSMENT OF PODS AND SEEDS DAMAGE DUE TO M. vitrata ATTACK.................................................................. 10 2.4 YIELD LOSS AND M. vitrata INFESTATION RELATIONSHIP........................................................................ 10 2.5 CONTROL MEASURES OF M. vitrata 11 2.5.1. Use of chemical pesticides.................................................... 11 2.5.1.1 Organophosphates............ 11 2.5.1.2 Synthetic pyrethroids........................................................ 11 2.5.1.3 Use of mixtures of organophosphate and pyrethroids................... 12 2.5.1.4 Advantages of chemical control.............................. 12 2.5.1.5 Disadvantages of chemical control 12 2.5.2 Botanical pesticides.............................................................................. 13 2.5.3 Use of microbial pesticides............................. 14 2.5.4 Semiochemicals as monitoring devices................................................ 15 2.5.5 Biological control.......................................... 16 2.5.5.1 Predators....................................................................... 17 2.5.5.2 Parasitoids and parasites............................................... 18 2.5.5.3 Importation and colonization................................................................ 19 5.5.54. Augmentation technique.............................................................................. 19 2.5.5.5 Conservation and Environment...................... 19 2.5.5.6 Advantages of biological control................................. 19 2.5.5.7 Disadvantages of biological control................................ 19 2.5.6 Cultural control measures of M. vitrata................................ 20 2.5.6.1. Intercropping........................................................................................ 20 2.5.6.2 Planting trap crops........................................................................................ 21 2.5.6.3 Planting density.......................................................................................... 21 2.5.6.4 Manipulating of date of planting............................................................ 22 2.5.6.5 Farm sanitation..................................................................................... 22 2.5.6.6 Advantages of cultural control measures of M. vitrata............. 22 2.5.6.7 Disadvantages of cultural control measures of M. vitrata........................... 23 2.5.7 Host plant resistance…………………………………. 23 2.5.8. Integrated pest management (IPM)......................... 24 vii 2.5.8.1 Advantages of IPM................................................... 25 2.5.8.2 Disadvantages of IPM......................................................... 25 2.5.8.3 Some barriers to IPM adoption................................................................. 26 2.5.8.4 Some established IPM control measures against M. vitrata........................ 26 3.0. CHAPTER THREE GENERAL METHODOLOGY............. 29 3.1 SURVEY ON FARMER'S COWPEA CULTIVATION PRACTICES………………………………………………. 29 3.1.1 Research design......................... 29 3.1.2. Population of the study..................... 29 3.1.3 Sample size and sampling technique....................................................... 29 3.1.4 Research instrument.............................................................................. 29 3.1.5 Validity and reliability of instrument..................................................