University of Kentucky UKnowledge University of Kentucky Doctoral Dissertations Graduate School 2011 EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO Merari Feliciano-Rivera University of Kentucky, [email protected] Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Feliciano-Rivera, Merari, "EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO" (2011). University of Kentucky Doctoral Dissertations. 225. https://uknowledge.uky.edu/gradschool_diss/225 This Dissertation is brought to you for free and open access by the Graduate School at UKnowledge. It has been accepted for inclusion in University of Kentucky Doctoral Dissertations by an authorized administrator of UKnowledge. For more information, please contact [email protected]. ABSTRACT OF DISSERTATION MERARI FELICIANO-RIVERA THE GRADUATE SCHOOL UNIVERSITY OF KENTUCKY 2011 EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO _____________________________________ ABSTRACT OF DISSERTATION _____________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Agriculture at the University of Kentucky By Merari Feliciano-Rivera Lexington, Kentucky 2011 Copyright © Merari Feliciano-Rivera 2011 ABSTRACT OF DISSERTATION EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO Kentucky reported a solid 13.1% growth in certified organic land from 1997 to 2002. The relative lack of research on disease management practices in Kentucky consistent with organic regulations is an issue that needs to be addressed to provide more reliable information to local farmers. Thus, the first objective of this research was to investigate the potential disease control obtained with natural, organically certifiable spray materials against Colletotrichum orbiculare in vitro and in vivo. The second objective was to test certifiable spray materials in combinations to identify synergistic interactions. The third objective was to evaluate Organic Material Review Institute (OMRI)-certified materials for managing Septoria leaf spot and early blight in tomato under field conditions. The fourth objective was to evaluate chitosan-based products against C. orbiculare in vitro and in vivo. Essential oils, Trilogy®, and Actinovate®, failed to suppress C. orbiculare in vitro as well as cucurbit anthracnose. Bicarbonate salts, Regalia®SC, Sonata®, copper based- products, lime sulfur and water-soluble chitosan showed high antifungal activity in vitro. Bicarbonate salts, Sonata®, Serenade Max®, Soil Gard 12G®, copper based-products and lime sulfur reduced anthracnose disease severity in vivo. In the s ynergism experiments only a limited number of mixtures showed synergistic interactions, but even in those cases, the effect was not consistent between experiments. The main response obtained was antagonism. In field experiments the most effective fungicides for managing Septoria leaf spot and early blight of tomato were copper-based fungicides. None of the biological-based products (Sonata® and Serenade Max®)), plant-based extracts (Trilogy® and Regalia® SC), chitosan, ammonium bicarbonate nor horticultural lime sulfur provided a significant reduction in disease severity. For the fourth objective, water-soluble chitosan with a molecular weight between 3 to 10 kDa (80 and 85% deacetylated) showed the highest antifungal activity among all chitosan-based products evaluated in vitro. Also, combining the in vitro and in vivo results suggest that the antifungal activity of chitosan-based products is molecular weight- and concentration-dependent. These results provide a significant advance in the evaluation of the efficacy of OMRI-certified materials and natural materials to help organic farmers in Kentucky and the USA to manage diseases. KEYWORDS: Alternaria solani, Septoria lycopersici, OMRI-certified materials, chitosan, synergism Merari Feliciano Rivera _______________________ Student Signature 5.31.2011 _______________________ Date EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO By Merari Feliciano-Rivera Paul Vincelli ________________________________________ Director of Dissertation Lisa Vaillancourt ________________________________________ Director of Graduate Studies 5.31.2011 ________________________________________ Date RULES FOR THE USE OF DISSERTATIONS Unpublished dissertations submitted for the Doctor's degree and deposited in the University of Kentucky Library are as a rule open for inspection, but are to be used only with due regard to the rights of the authors. Bibliographical references may be noted, but quotations or summaries of parts may be published only with the permission of the author, and with the usual scholarly acknowledgments. Extensive copying or publication of the dissertation in whole or in part also requires the consent of the Dean of the Graduate School of the University of Kentucky. A library that borrows this dissertation for use by its patrons is expected to secure the signature of each user. Name Date ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ _______________________________________________________________________ DISSERTATION Merari Feliciano-Rivera The Graduate School University of Kentucky 2011 EFFICACY OF ORGANICALLY CERTIFIABLE MATERIALS AND NATURAL COMPOUNDS AGAINST FOLIAR HEMIBIOTROPHIC AND NECROTROPHIC FUNGI IN CANTALOUPE AND TOMATO _____________________________________ DISSERTATION _____________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Agriculture at the University of Kentucky By Merari Feliciano-Rivera Lexington, Kentucky Director: Dr. Paul Vincelli Lexington, Kentucky Copyright © Merari Feliciano-Rivera 2011 ACKNOWLEDGMENTS “A thankful heart is not only the greatest virtue, but the parent of all other virtues.” Cicero It is a pleasure to thank those who made this dissertation possible and those who supported me throughout the process. I owe my deepest gratitude to Dr. Vincelli for giving me the opportunity to realize this project and for encouragement, supervision and support from the beginning to the end of this process. I would like to thank my committee members: Dr. Christopher Schardl, Dr. Kenneth Seebold and Dr. Mark Williams for all of the contributions, suggestions, corrections and insights during these years. In addition I would also like to thank my family and friends for the continuous support throughout these years. Thank you to my mother, Aida Rivera and father Jose Feliciano, who gave me the moral support and courage required to complete this chapter in my life. Thanks to my grandmother, Luisa, and siblings Jocelyn and Javier, for your support and encouragement to make this dream real. A special thank you to my husband, Misael Olmo, for his unconditional support, love and motivation. My deepest thanks to all members of the Department of Plant Pathology, especially Doug Brown for the help with the greenhouse experiments; Ed Dixon, Bernadette Amsden and the Extension Group for the technical collaboration. iii TABLE OF CONTENTS Acknowledgment………………………………………………………………………..iii List of tables…………………………………………………………………………….vii List of figures…………………………………………………………………………….ix Chapter 1: Literature Review...........................................................................................1 Organic production systems……………………………………………………….2 Materials allowed in organic production systems…………………………………5 OMRI-certified materials………………………………………………….5 Essential oils………………………………………………………………5 Bicarbonate salts…………………………………………………………..8 Cucurbit anthracnose and management in organic production systems…………..9 Early blight and Septoria leaf spot in tomato…………………………………….13 Alternaria solani…………………………………………………………13 Septoria lycopersici……………………………………………………...14 Management of early blight and septoria leaf spot in organically produced tomatoes……………………………………………………….14 Chitosan………………………………………………………………………….19 Antifungal activity of chitosan…………………………………………...20 Role of chitosan in plant disease resistance……………………………...23 Chapter 2: In vitro and in vivo evaluation of essential oils, bicarbonate salts and OMRI- certified materials against Colletotrichum orbiculare Introduction………………………………………………………………………27 Materials and Methods…………………………………………………………...28 Fungal Isolate…………………………………………………………….28 Dilutions and preparations of materials for in vitro and in vivo experiments……………………………………………………………....29 In vitro measurement of