South Dakota State University Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange Electronic Theses and Dissertations 2019 Some Studies on Leaf Spot of Oats and Triticale Mohammed Abdullah Lashram South Dakota State University Follow this and additional works at: https://openprairie.sdstate.edu/etd Part of the Agronomy and Crop Sciences Commons, and the Plant Pathology Commons Recommended Citation Lashram, Mohammed Abdullah, "Some Studies on Leaf Spot of Oats and Triticale" (2019). Electronic Theses and Dissertations. 3125. https://openprairie.sdstate.edu/etd/3125 This Thesis - Open Access is brought to you for free and open access by Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. For more information, please contact [email protected]. SOME STUDIES ON LEAF SPOT OF OATS AND TRITICALE BY MOHAMMED ABDULLAH LASHRAM A thesis submitted in partial fulfillment of the requirements for the Master of Science Major in Plant Science South Dakota State University 2019 iii ACKNOWLEDGEMENTS First and foremost, I wish to pay my sincere regards to the Almighty, who provided me with an opportunity, to begin with, my research for my MS and making me conduct it successfully. My most heartfelt thanks to my advisor Dr. Shaukat Ali for providing me a platform for working on this project as a master thesis. He has been my source of inspiration and encouragement throughout my stay at SDSU. I especially want to thank Dr. Sunish Kumar Sehgal, my committee member, for his continuous support and guidance to accomplish my degree. I also like to thank Dr. Byamukama Emmanuel, my committee member, for his valuable insights and comments while conducting my research and beyond. I would like specially to thank Dr. Xiangming Guan, Graduate Faculty representative, for his sweet harmony and serve on my committee. It is an honor for me to express my deep indebtedness to Dr. Madhav Nepal as well as Surendra Neupane and Ethan Andersen (his students) allowing me to work in his laboratory and learned some molecular techniques. I highly appreciate Mr. Richard Geppert for his technical help in samples collection, lab, and greenhouse work. Thank you to all my colleagues: Navjot Kaur, Girma Tadesse Ayana, Jytirmoy Halder, Rami Altameemi, Sidhu Jagdeep, Collins Bugingo, Zunera Shabbir and Mustafa Aljadi who have provided their utter encouragement in making this research a wonderful experience and my stay at SDSU. Also, I am thankful to them for their continuous support in performing my lab work, data collection, and working with statistical software for data analysis. I am grateful to the Department Head Dr. David Wright who provided me an excellent opportunity to join the department as a graduate student and accomplish my MS degree. I like to thank my family and friends for their inspiration and patience during my iv MS at SDSU and studying abroad. At the last but not least, I appreciate Jazan University, Kingdom of Saudi Arabia, South Dakota Wheat Commission, and SDSU AES for their financial support for completing my MS degree. v CONTENTS LIST OF TABLES ........................................................................................................... viii LIST OF FIGURES ........................................................................................................... ix ABSTRACT ........................................................................................................................ x CHAPTER 1 (Literature review) ........................................................................................ 1 Oat ....................................................................................................................................... 1 Origin and History .......................................................................................................... 1 Health benefits ................................................................................................................ 2 Production ....................................................................................................................... 2 Biotic stresses in oat production ......................................................................................... 2 Drechslera avenae leaf spot ................................................................................................ 2 Drechslera avenae history .............................................................................................. 2 Drechslera avenae distribution and significance ............................................................ 4 Host range ....................................................................................................................... 6 Host resistance ................................................................................................................ 6 Drechslera avenae leaf spot symptoms and disease cycle ............................................. 6 Role of fungal effectors (toxins) in disease development ............................................... 7 Disease management ....................................................................................................... 8 Wheat ................................................................................................................................ 10 Origin, history, and domestication of wheat ................................................................. 10 Triticale ............................................................................................................................. 12 Origin, and history of triticale ....................................................................................... 12 Uses of triticale ............................................................................................................. 13 Tan spot ............................................................................................................................. 15 Importance .................................................................................................................... 15 History ........................................................................................................................... 15 Distribution ................................................................................................................... 16 Host range ..................................................................................................................... 17 Symptoms and significance .......................................................................................... 18 Virulence variation in the pathogen .............................................................................. 19 vi Role of Host-Selective toxins in Disease development ................................................ 20 Disease cycle ................................................................................................................. 22 Disease management ..................................................................................................... 23 Rational, Significance and Objectives .......................................................................... 26 Literature cited .............................................................................................................. 29 CHAPTER 2 ..................................................................................................................... 51 Survey of oat leaf spot pathogens in South Dakota and evaluation of a worldwide collection of oats germplasm against Drechslera avenae leaf spot .................................. 51 ABSTRACT ...................................................................................................................... 51 Introduction ................................................................................................................... 53 Materials and methods .................................................................................................. 54 Recovery and characterization of Drechslera avenae isolates from oat. ................. 54 Plant Materials .......................................................................................................... 55 Inoculum preparation, plants inoculation, and disease rating ................................... 56 Data analysis ................................................................................................................. 57 Results ........................................................................................................................... 57 Recovery and characterization of Drechslera avenae .............................................. 57 Reaction of oat genotypes to leaf spot ...................................................................... 58 Discussion ..................................................................................................................... 63 Literature cited .............................................................................................................. 66 CHAPTER 3 ..................................................................................................................... 70 Characterization of a global collection of triticale genotypes to Pyrenophora