Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2014 Pesticide free methods of maize weevil control in stored maize for developing countries Denis Bbosa Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Agriculture Commons, and the Bioresource and Agricultural Engineering Commons Recommended Citation Bbosa, Denis, "Pesticide free methods of maize weevil control in stored maize for developing countries" (2014). Graduate Theses and Dissertations. 14083. https://lib.dr.iastate.edu/etd/14083 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Pesticide free methods of maize weevil control in stored maize for developing countries by Denis Bbosa A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Co-majors: Agricultural and Biosystems Engineering; Biorenewable Resources and Technology Program of Study Committee: Thomas J. Brumm, Major Professor Carl J. Bern Kurt A. Rosentrater D. Raj Raman Iowa State University Ames, Iowa 2014 Copyright © Denis Bbosa, 2014. All rights reserved. ii DEDICATION This thesis is dedicated to my mom, Ms. Jane Nantongo, and to my siblings, Miriam Nakabiito and Ronald Sserunkuma. iii TABLE OF CONTENTS Page DEDICATION .......................................................................................................................... ii LIST OF FIGURES ................................................................................................................ vii LIST OF TABLES ................................................................................................................. viii NOMENCLATURE ................................................................................................................ ix ACKNOWLEDGEMENTS ...................................................................................................... x ABSTRACT ............................................................................................................................ xii CHAPTER 1: INTRODUCTION ............................................................................................ 1 Thesis Organization .............................................................................................................. 1 Literature Review ................................................................................................................. 1 Maize ................................................................................................................................ 1 Maize weevil ..................................................................................................................... 5 Maize storage .................................................................................................................... 6 Hermetic storage ............................................................................................................... 8 Amaranth .......................................................................................................................... 9 Physical disturbance as a control measure to insects ...................................................... 12 Synopsis .......................................................................................................................... 13 General Objectives .............................................................................................................. 14 iv References ............................................................................................................................... 14 CHAPTER 2: EVALUATION OF HERMETIC MAIZE STORAGE STEEL BARRELS FOR SMALLHOLDER FARMERS ...................................................................................... 19 Abstract ................................................................................................................................... 19 Introduction ............................................................................................................................. 20 Material and Methods ............................................................................................................. 22 Containers ........................................................................................................................... 22 Weevils ............................................................................................................................... 22 Experimental procedure ...................................................................................................... 23 Measurements ..................................................................................................................... 23 Results and Discussion ........................................................................................................... 24 Weevil mortality ................................................................................................................. 24 Temperature ........................................................................................................................ 28 Relative humidity ................................................................................................................ 28 Maize moisture content (MC) ............................................................................................. 29 Mechanical Damage (MD) ................................................................................................. 30 Broken corn and foreign material (BCFM) ........................................................................ 30 Test weight (TW) ................................................................................................................ 31 Aflatoxins ............................................................................................................................ 31 Oxygen sensor readings for HS1, HS2 and HS3 (T=120-122 days) .................................. 32 v Oxygen sensor readings for HS1, HS2 and HS3 (T=129-150 days) .................................. 32 Conclusions ............................................................................................................................. 34 Implications ............................................................................................................................ 35 Acknowledgements ................................................................................................................. 35 References ............................................................................................................................... 35 CHAPTER 3: EFFECT OF BLENDING MAIZE KERNELS WITH AMARANTH DURING STORAGE ON MAIZE WEEVIL MORTALITY ................................................ 40 Abstract ................................................................................................................................... 40 Introduction ............................................................................................................................. 41 Methods and Materials ............................................................................................................ 43 Containers ........................................................................................................................... 43 Maize weevils ..................................................................................................................... 43 Experimental maize and amaranth ...................................................................................... 43 Measurements and statistical analysis ................................................................................ 44 Results and Discussion ........................................................................................................... 44 Conclusions ............................................................................................................................. 49 Acknowledgements ................................................................................................................. 50 References ............................................................................................................................... 50 CHAPTER 4: EFFECT OF STORAGE CONTAINER PHYSICAL DISTURBANCE ON MAIZE WEEVIL MORTALITY .................................................................................... 53 vi Abstract ................................................................................................................................... 53 Introduction ............................................................................................................................. 54 Methods and Materials ............................................................................................................ 56 Containers ........................................................................................................................... 56 Maize .................................................................................................................................. 57 Weevils ..............................................................................................................................