Effect of Irrigation Interval on Physiological and Growth Parameters of Moringa oleifera and Moringa peregrina Seedlings By Wafa Elhag Adam Abaker B.Sc. (Honours) Forestry University of Khartoum, 2006 A thesis submitted in fulfillment of the requirement for the Degree of M.Sc. in Forestry Supervisor Dr. Essam Ibrahim Warrag Department of Silviculture Faculty of Forestry University of Khartoum January, 2010 DEDICATION To my family To my friends To my colleagues Wafa i ACKNOWLEDGEMENT To begin with thanks to Allah, for his great blessing. I would like to thank my supervisor Dr. Essam Ibrahim Warrag, Department of Silviculture, Faculty of Forestry, University of Khartoum for his close supervision, guidance and useful suggestions. Also thanks and deep gratitude to Dr. Mudawi Elobeid, Department of Silviculture, Faculty of Forestry, University of Khartoum for his assistance and valuable advices. Deep thanks to my family for their help, great support and encouragement, also very special thanks to my sister Dalia for her unlimited support and assistance through the period of study. Thanks are also sent to my dear colleagues all teaching assistants in the Faculty of Forestry, University of Khartoum, for their assistance particularly during the period of the experiment. ii TABLE OF CONTENTS DEDICATION ................................................................................................ i ACKNOWLEDGEMENT ............................................................................. ii TABLE OF CONTENTS ............................................................................ iii LIST OF TABLES ......................................................................................... v ABSTRACT ................................................................................................. vii ARABIC ABSTRACT ................................................................................. ix CHAPTER ONE ............................................................................................ 1 INTRODUCTION ......................................................................................... 1 1.1 Background .............................................................................................. 1 1.2 Justification .............................................................................................. 3 1.3 Problem statement.................................................................................... 3 1.4 Objectives ................................................................................................ 4 CHAPTER TWO ........................................................................................... 5 LITERATURE REVIEW .............................................................................. 5 2.1 Description of moringa species ............................................................... 5 2.1.1 Moringa oleifera (Lam.) ................................................................... 5 2.1.2 Moringa peregrina (Forsk.) .............................................................. 6 2.2 Importance of water for plants ................................................................. 7 2.3 Cell water relation .................................................................................... 8 2.4 Development of water stress .................................................................... 8 2.5 Transpiration .......................................................................................... 10 2.6 Impact of water stress ............................................................................ 11 2.6.1 Stomatal response ........................................................................... 12 2.6.2 Photosynthesis ................................................................................. 13 2.7 Growth and allocations .......................................................................... 14 CHAPTER THREE ..................................................................................... 15 MATERIALS AND METHODS ................................................................ 15 3.1 Seed source ............................................................................................ 15 3.2 Raising of seedlings ............................................................................... 15 3.3 Water treatment and experimental design ............................................. 16 3.4 Measurements ........................................................................................ 16 3.4.1 Growth parameters .......................................................................... 16 3.4.2 Gas exchange measurements .......................................................... 17 3.5 Statistical analysis .................................................................................. 17 CHAPTER FOUR ........................................................................................ 18 RESULTS .................................................................................................... 18 4.1 Variation within each species ................................................................ 18 4.1.1 Shoot height .................................................................................... 18 iii 4.1.2 Number of Leaves ........................................................................... 18 4.1.3 Root length ...................................................................................... 23 4.1.4 Dry mass.......................................................................................... 23 4.1.5 Gas exchange parameters ................................................................ 23 4.1.6 Gas exchange parameters after rewatering ..................................... 28 4.2 Variation between the two species ........................................................ 31 4.2.1 Shoot height .................................................................................... 31 4.2.2 Number of leaves ............................................................................ 31 4.2.3 Root length ...................................................................................... 31 4.2.4 Dry mass.......................................................................................... 31 4.2.5 Gas exchange parameters ................................................................ 38 4.2.6 Gas exchange parameters after rewatering ..................................... 38 CHAPTER FIVE ......................................................................................... 41 DISCUSSION .............................................................................................. 41 5.1 Growth performance .............................................................................. 41 5.2 Dry mass ................................................................................................ 42 5.3 Gas exchange parameters ...................................................................... 44 5.4 Gas exchange after rewatering ............................................................... 44 CHAPTER SIX ............................................................................................ 46 CONCLUSIONS AND RECOMMENDATIONS ...................................... 46 6.1 Conclusions ............................................................................................ 46 6.2 Recommendations .................................................................................. 47 REFERENCES ............................................................................................ 48 iv LIST OF TABLES Table Page 1 Effect of irrigation intervals on shoot height (cm) of M. oleifera seedlings over 12 weeks 19 2 Effect of irrigation intervals on shoot height (cm) of M. peregrina seedlings over 12 weeks 20 3 Effect of irrigation intervals on the number of leaves of M. oleifera seedlings over 12 weeks 21 4 Effect of irrigation intervals on the number of leaves of M. peregrina seedlings over 12 weeks 22 5 Effect of irrigation intervals on the root length (cm) of M. oleifera seedlings at three harvests 24 6 Effect of irrigation intervals on the root length (cm) of M. peregrina seedlings at three harvests 24 7 Effect of irrigation intervals on the dry mass of M. oleifera seedlings in the first harvest 25 8 Effect of irrigation intervals on the dry mass of M. peregrina seedlings in the first harvest 25 9 Effect of irrigation intervals on the dry mass of M. oleifera seedlings in the second harvest 26 10 Effect of irrigation intervals on the dry mass of M. peregrina seedlings in the second harvest 26 11 Effect of irrigation intervals on the dry mass of M. oleifera seedlings in the third harvest 27 12 Effect of irrigation intervals on the dry mass of M. peregrina seedlings in the third harvest 27 13 Effect of irrigation intervals on the gas exchange parameters of M. oleifera seedlings 29 14 Effect of irrigation intervals on the gas exchange parameters of M. peregrina seedlings 29 15 Effect of rewatering on the gas exchange parameters of M. oleifera seedlings 30 v 16 Effect of rewatering on the gas exchange parameters of M. peregrina seedlings 30 17 Variation between M. oleifera and M. peregrina seedlings at each irrigation interval in shoot height (cm) over 12 weeks 32 18 Variation between M. oleifera and M. peregrina seedlings at each irrigation interval in the number of leaves over 12 weeks 33 19 Variation between M. oleifera and M. peregrina seedlings at each irrigation interval in root length (cm) 34 20