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The Evaluation of New Harvest Aid Herbicides for Dry Bean (Phaseolus Vulgaris L.) Production in Manitoba

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The Evaluation of New Harvest Aid Herbicides for Dry Bean (Phaseolus Vulgaris L.) Production in Manitoba The Evaluation of New Harvest Aid Herbicides for Dry Bean (Phaseolus vulgaris L.) Production in Manitoba. BY KRISTINE APRIL WADDELL A Thesis Submitted to the Faculty of Graduate Studies of The University of Manitoba In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE Department of Plant Science University of Manitoba Winnipeg, Manitoba Copyright © 2013 by Kristine A. Waddell THE UNIVERSITY OF MANITOBA FACULTY OF GRADUATE STUDIES ******* COPYRIGHT PERMISSION The Evaluation of New Harvest Aid Herbicides for Dry Bean (Phaseolus vulgaris L.) Production in Manitoba. By KRISTINE APRIL WADDELL A Thesis Submitted to the Faculty of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE © Copyright by Kristine A. Waddell 2013 Permission has been granted to the Library of the University of Manitoba to lend/sell copies of this thesis, to the National Library of Canada to microfilm this thesis and to lend or sell copies of the film, and to the University Microfilms Inc. to publish an abstract of this thesis. This reproduction or copy of this thesis has been made available by authority of the copyright owner solely for the purpose of private study and research, and may only be reproduced and copied as permitted by copyright laws or with express written authorization from the copyright owner. ii TABLE OF CONTENTS ABSTRACT .................................................................................................................................. vii ACKNOWLEDGMENTS .............................................................................................................. x LIST OF TABLES ......................................................................................................................... xi LIST OF FIGURES ...................................................................................................................... xii GLOSSARY OF TERMS ............................................................................................................ xiii 1.0 INTRODUCTION .................................................................................................................... 1 2.0 LITERATURE REVIEW ......................................................................................................... 4 2.1 Common Dry Bean ................................................................................................................ 4 2.1.1 History ............................................................................................................................ 4 2.1.2 Plant Morphology ........................................................................................................... 5 2.1.3 Global Dry Bean Production .......................................................................................... 7 2.1.4 Manitoba Dry Bean Production ...................................................................................... 8 2.2 Desiccants ........................................................................................................................... 12 2.2.1 History .......................................................................................................................... 12 2.2.2 Current Use ................................................................................................................... 13 2.2.2.1 Paraquat ................................................................................................................. 14 2.2.2.2 Diquat .................................................................................................................... 15 2.2.2.3 Glufosinate Ammonium ........................................................................................ 16 iii 2.2.2.4 Saflufenacil ............................................................................................................ 18 2.2.2.5 Flumioxazin and Carfentrazone-ethyl ................................................................... 19 2.3 Glyphosate .......................................................................................................................... 19 2.3.1 History of Glyphosate .................................................................................................. 19 2.3.2 Current Use Patterns ..................................................................................................... 22 2.3.2.1 Pre-seed/Pre-emergent Weed Control ................................................................... 22 2.3.2.2 In-Crop Weed Control ........................................................................................... 23 2.3.2.3 Pre-harvest Glyphosate Application ...................................................................... 23 2.3.3 Limitations and Concerns for Glyphosate .................................................................... 24 2.3.3.1 Chemical Limitations ............................................................................................. 24 2.3.3.2 Potential Environmental Impact and Toxicity to Non-Target Organisms ............. 25 2.3.3.3 Residue Accumulation in Seed .............................................................................. 26 2.3.3.4 Effect of Glyphosate on Seed Yield and Quality ................................................... 28 2.3.3.5 Maximum Residue Limits ..................................................................................... 28 2.4 Research Objectives ............................................................................................................. 30 3.0 EVALUATION OF TANKMIXING CONTACT HERBICIDES WITH GLYPHOSATE AT PREHARVEST TIMING ON THE ACCUMULATION OF RESIDUES IN DRY BEAN SEED .............................................................................................. 31 3.1 Introduction ......................................................................................................................... 32 3.2 Methods and Materials ........................................................................................................ 34 iv 3.3 Results ................................................................................................................................. 42 3.3.1 Efficacy and Speed of Desiccation ............................................................................... 42 3.3.1.1 Diquat .................................................................................................................... 42 3.3.1.2 Glufosinate ............................................................................................................. 43 3.3.1.3 Carfentrazone-ethyl ............................................................................................... 43 3.3.1.4 Flumioxazin ........................................................................................................... 43 3.3.1.5 Saflufenacil ............................................................................................................ 44 3.3.1.6 Alternative Harvest Aid Herbicides Alone in Comparison to Diquat ................... 44 3.3.2 Yield and Quality of Bean Seed ................................................................................... 48 3.3.3 Moisture Content of Bean Seed .................................................................................... 48 3.3.4 Herbicide Residue Analysis .......................................................................................... 50 3.4 Discussion ........................................................................................................................... 50 3.5 Conclusion ........................................................................................................................... 57 4.0 EFFECT OF APPLICATION TIMING OF TWO HARVEST AID HERBICIDES (GLYPHOSATE AND SAFLUFENACIL) ON ACCUMULATION OF RESIDUE IN DRY BEAN SEED ....................................................................................................................... 58 4.1 Introduction ......................................................................................................................... 59 4.2 Methods and Materials ........................................................................................................ 61 4.3 Results ................................................................................................................................. 65 4.3.1 Efficacy and Speed of Desiccation ............................................................................... 65 v 4.3.2 Yield ............................................................................................................................. 72 4.3.3 Seed Size ....................................................................................................................... 74 4.3.4 Thousand Kernel Weight .............................................................................................. 77 4.3.5 Seed Moisture Content ................................................................................................. 78 4.3.6 Herbicide Residue Analysis .......................................................................................... 81 4.4 Discussion ........................................................................................................................... 85 4.5 Conclusion ........................................................................................................................... 90 5.0 EVALUATION OF
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