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Epidemiology, Virulence and Molecular Diversity in Blast [Magnaporthe Grisea (Hebert) Barr.] of Pearl Millet [Pennisetum Glaucum (L.) R

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Epidemiology, Virulence and Molecular Diversity in Blast [Magnaporthe Grisea (Hebert) Barr.] of Pearl Millet [Pennisetum Glaucum (L.) R “Epidemiology, virulence and molecular diversity in blast [Magnaporthe grisea (Hebert) Barr.] of pearl millet [Pennisetum glaucum (L.) R. Br.] and resistance in the host to diverse pathotypes” T. YELLA GOUD M.Sc. (Ag) DOCTOR OF PHILOSOPHY IN AGRICULTURE (PLANT PATHOLOGY) 2015 CERTIFICATE Mr T. YELLA GOUD has satisfactorily prosecuted the course of research and that the thesis entitled “Epidemiology and virulence diversity in blast [Magnaporthe grisea (Hebert) Barr.] of pearl millet [Pennisetum glaucum (L.) R. Br.] and resistance in the host to diverse pathotypes” submitted is the result of original research work and is of sufficiently high standard to warrant its presentation to the examination. I also certify that the thesis nor its part thereof has not been previously submitted by him for a degree of any university. Date: Chairperson CERTIFICATE This is to certify that the thesis entitled “Epidemiology and virulence diversity in blast [Magnaporthe grisea (Hebert) Barr.] of pearl millet [Pennisetum glaucum (L.) R. Br.] and resistance in the host to diverse pathotypes” submitted in partial fulfillment of the requirements for the degree of „Doctor of Philosophy in Agriculture‟ of the Professor Jayashankar Telangana State Agricultural University, Hyderabad is a record of the bonafide original research work carried out by Mr. T. YELLA GOUD under our guidance and supervision. No part of the thesis has been submitted by the student for any other degree or diploma. The published part and all assistance received during the course of the investigations have been duly acknowledged by the author of the thesis. Thesis approved by the Student Advisory Committee Chairperson : Dr. G. UMA DEVI Professor and Head (Signature) Department of Plant Pathology College of Agriculture, Rajendranagar Co-Chairperson : Dr. RAJAN SHARMA Senior Scientist (Cereals Pathology) (Signature) and Head, Plant Quarantine Laboratory ICRISAT, Patancheru, Hyderabad, India. Member : Dr. V. KRISHNA RAO Professor and Univ. Head (Signature) Dept. of Plant Pathology & Co-ordinator Farmers Call Center, PJTSAU, Seethaphalmandi, Secunderabad Member : Dr. T. RAMESH BABU Dean of Agriculture (Signature) ANGRAU, Rajendranagar, Hyderabad Member : Dr. S. SOKKA REDDY Professor and Univ. Head, (Signature) Molecular Biology and Biotechnology, PJTSAU, Rajendranagar, Hyderabad. Date of final viva-voice: DECLARATION I, THANDU YELLA GOUD, hereby declare that the thesis entitled “EPIDEMIOLOGY, VIRULENCE AND MOLECUALR DIVERSITY IN BLAST [Magnaporthe grisea (Hebert) Barr.] OF PEARL MILLET [Pennisetum glaucum (L.) R. Br.] AND RESISTANCE IN THE HOST TO DIVERSE PATHOTYPES” submitted to the Professor Jayashankar Telangana State Agricultural University for the degree of Doctor of Philosophy in Agriculture is the result of original research work done by me. I also declare that no material contained in the thesis has been published earlier in any manner. Place: (THANDU YELLA GOUD) I. D. No. RAD/11-29 Date: ACKNOWLEDGEMENTS At the outset for me the time has come to gather the words for expressing my gratitude towards all those who helped me in building my career. Fervently and modestly, I extol the genuine cooperation, inspiration, advice and affection offered to me by the Chairperson of my Advisory Committee Dr. G. Uma Devi, Professor and Head, Department of Plant Pathology, College of Agriculture, Rajendranagar, Hyderabad, right from the initiation of the work to shaping of the manuscript. The present work bears at every stage of her impression of her counsel and concrete suggestions, careful reasoned criticism and meticulous attention to details. It was indeed a rare privilege for me to work under her emending inspiration and indominable spirit. I am greatly beholden beyond words to express my deep sense of gratitude and a great privilege to work under the able and highly exceptional guidance of Co-chairperson Dr. Rajan Sharma, Senior Scientist, Cereals Pathology and Head Plant Quarantine lab, ICRISAT, Patancheru, Hyderabad, for his brilliant counsel, constructive suggestions, indefatigable guidance, evincive criticism and inspiring encouragement to embellish the present study. It gives me great pleasure to express my deep sense of gratitude to Dr.V. Krishna Rao, Professor and University head, Department of Plant Pathology and Co-ordinator, Farmers Call Center, PJTSAU, Seethaphalmandi, Secunderabad, Rajendranagar for his cooperation and kindness during my study. I sincerely extend my gratitude to Dr. T. Ramesh Babu, Professor Department of Entomology, Dean of Agriculture, ANGRAU, member of my advisory committee for his valuable suggestions during the course of investigation. I owe my effusive thanks to Dr. S. Sokka Reddy, Professor and University Head, Molecular Biology and Biotechnology and member of my advisory committee for his valuable suggestions and affectionate encouragement during the course of investigation. I express my sincere thanks to the staff members Dr. P. Narayan Reddy, Dr. B. Vidya Sagar, Dr. Bharathi N Bhatt, Dr. B. Pushpavati, Dr. K. Vijay Krishna Kumar, Dr. B. Kishore Varma of Department of Plant Pathology, Dr. Mahendar Thudi Scientist, Center for Excellence in Genomics (CEG), Dr. Santosh Deshpande Scientist, Dr. S. K. Gupta Senior scientist, Dryland cereals, ICRISAT and AICRIP scientists involved in the blast virulence nursery studies. I allocate heartful love and affection from inner core of heart to my ever loved parents Shri. T. Muthyalu and Smt. Punyavathi who taught the concepts of life and dedicated efforts to educate me to this level I also allocate respect to my lovable family members and cousins, for their unbounding love and dedicated efforts without whose encouragement and invaluable moral support, the thesis would not have seen the light of the day. I owe my gratitude towards my friends, Kishan, Naveen, Giri, Sadaiah, Anil, Kiran, Shyam, Prashanth, Pavani, Divya, and Jadesha, juniors Naveen, Rajeshwar Reddy, Rajender, Padmaja, Raviteja, Raj, Shwetha, and Srinivas for their cheerful company, help, encouragement, co-operation in my college life. My sincere thanks to Mr. Humaiun, Mr. Madhavan, Mr. Vishal, Mr. Ahmed, Mr. Mohan Rao, Mr. Aziz, Mr. Murali, Mr. Kranthi, Mr. Chari, Mr. Benarji, Mr. Malla Reddy, Mrs. Lakshamma and Mrs. Mallamma and all other staff of ICRISAT for their cooperation and help. I cordially convey my special gratitude to my seniors Madhavi, Kiran Babu, Shanker, Praveen, Suresh, Raghu, Gopika, Jeevan Raja Ram and who shared my fears and tears I felt elated to express my bountiful thanks to those who directly or indirectly helped me in successful completion of thesis work. The financial assistance rendered by PJTSAU and ICRISAT is greatly acknowledged. I convey my wholehearted thanks to many of my well-wishers and to other friends requesting their forgiveness for not mentioning them here by name. Thandu Yella Goud CONTENTS CHAPTER NO. TITLE PAGE NO. I INTRODUCTION II REVIEW OF LITERATURE III MATERIALS AND METHODS IV RESULTS AND DISCUSSION V SUMMARY LITERATURE CITED APPENDICES LIST OF TABLES Table Page Title No. No. 3.1 Pearl millet foliar blast severity rating scale List of pearl millet differential lines/genotypes along with their 3.2 pedigree Geographical characteristics and experimental conditions of pearl 3.3. millet blast resistance screening at six locations in India during Kharif 2013 and 2014 Sources of Magnapothe grisea isolates collected from different 4.1. states of India Isolates of Magnaporthe grisea of different hosts collected from 4.2. different states Pathogenicity of Magnaporthe grisea isolates collected from 4.3 different states Analysis of variance (ANOVA) of radial growth of pearl millet blast (Magnaporthe grisea) isolates MgPM 45, MgPM 53, MgPM 4.4. 56 and MgPM 118 on PDA and OMA at different temperatures and pH levels under in vitro conditions Radial growth (cm) of pearl millet blast (Magnaporthe grisea) isolates MgPM 45, MgPM 53, MgPM 56 and MgPM 118 on PDA 4.5 and OMA at different temperatures and pH levels under in vitro conditions Sporulation of isolates of Magnaporthe grisea MgPM 45, MgPM 4.6 53, MgPM 56 and MgPM 118 on OMA and PDA at different temperature and pH levels under in vitro conditions Effect of different pH levels of OMA medium and temperatures on 4.7 colony morphology of Magnaporthe grisea isolates MgPM 45, 53, 56 and 118 infecting pearl millet Effect of different pH levels of PDA medium and temperatures on 4.8 colony morphology of Magnaporthe grisea isolates MgPM 45, 53, 56 and 118 infecting pearl millet Cultural and morphological characteristics of sixty five 4.9 Magnaporthe grisea isolates collected from pearl millet from different location on OMA medium Analysis of variance (ANOVA) for leaf blast severity of sixty five 4.10 isolates of Magnaporthe grisea on ten pearl millet host differential lines Disease severity (1-9 scale) of blast on ten different pearl millet 4.11 lines tested against sixty five isolates of Magnaporthe grisea collected from India under green house conditions Genetic diversity among isolates Magnaporthe grisea isolates by 4.12 Universal Rice Primers (URP) Analysis of molecular variance (AMOVA) for pearl millet and non- 4.13a pearl millet infecting populations of Magnaporthe grisea Analysis of molecular variance (AMOVA) for pearl millet infecting 4.13b populations of Magnaporthe grisea Effect of different leaf wetness durations on per cent disease index 4.14 on pearl millet (ICMB 95444) blast Effect of different leaf wetness durations on pearl millet (ICMB 4.15 95444) blast
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