Abstract:
First and foremost, all acclamation and thanks goes to Almighty God, the Lord of all things and Master of the Day of Judgment who has been helping me in every aspect of my life, including this thesis work.
Furthermore, I would like to express my deep and sincere gratitude to my major advisor Lemma Wogi (PhD) who gave me tireless support and guidance during the course of this work starting from proposal development, field experiment and to the final write-up of this manuscript. I extend my special thanks and appreciation to my co-advisor Selamyehun Kidanu (PhD) whose contribution for accomplishment of this work. His advice, help and encouragement during the work and write-up of this thesis has been great, and highly appreciated.
My thank also goes to workers of Ministry of Agriculture, Department of soil fertility, to His Excellence Kaba Urgesa (PhD), Mr. Habtamu Hailu, Mr. Mulugeta Abera for their support and help in provision of inputs and other materials without any reservation. I would like to thanks National Soil laboratory technician for their giant support during soil analysis.
Moreover, I would like to take this opportunity to extend my sincere and deepest thanks to Ameya District Agricultural and Rural Development Bureau staff; Mr. Dereba Terefa, Mulugeta Serbessa and Tekela Hirpasa for their irreplaceable technical assistance and moral support.
My sincere appreciation goes to my beloved wife Mrs. Burtukan Tolera, for her caring, charming temperament, requisite assistance, sympathy and patience throughout the study period, and my sweet little girls, Jitu and Lensa who time after time asked “when will I finish the study?” I thankful to my mother, Gelane and Brothers Samuel and Bullo for their partnership
