ABSTRACT
Flooding has been described as one of the most important environmental factors determining the distribution of salt marsh plants. We studied the impact of five water levels on the germination and establishment of the invasive cord-grass spartina deniflora. Plant house experiment was carried out to determine the effects of time and depth of flooding on the survival and growth of rice. Data showed that time and depth of flooding had significant effects on the survival and growth of rice.
The germination rate was decrease gradually with depth. There was no seedling emergence from depth deeper than 4cm; however seedling at 8cm depth all died. Plant rooted at 4cm presented the highest quantum efficiency of photo-system 11 with slightly lower maximum net photosynthesis rate than other plants over 4cm depth reflecting high photo-protection levels, together with low nitrogen and pigments contents.
Water level depth reduced shoot relative growth rate (RGR). The results could be useful to fight S, densiflora invasion because artificial inundation of invaded marshes to a water depth of 8cm would prevent its establishment from seed bank.
TABLE OF CONTENTS
Cover Page……………………………………………………………….
Title Page …………………………………………………………………
Approval Page …………………………………………………………..
Dedication …………………………………………………………………..
Acknowledgement …………………………………………………………
Abstract …………………………………………………………………………..
Table of contents
CHAPTER ONE
1.0 INTRODUCTION ………………………………………………………………
1.1 Background of the study ……………………………………………….
1.2 Objectives of the study …………………………………………………..
1.3 Justification of the study…………………………………………………..
CHAPTER TWO
2.0 LITERATURE REVIEW ……………………………………………………….
2.1 Overview of Rice Cropping ……………………………………………
2.2 Effect of Flooding on Rice Growth …………………………………
2.3 Types of Rice Grown ……………………………………………………..
2.4 Techniques of Flood control. ………………………………………..
2.5 Additional traits probably involved in the survivalof anaerobic soils …………………………..
2.6 Rice adaptation to anaerobic system……………………………
2.7 Genetic Variation in flooding Tolerance during
germination and Early Growth in Rice……………………………..
2.8 Mobilization of stored carbohydrates……………………………
2.9 Role of Rice hormones under Flooded conditions …………
2.10 Adaptation of Rice to Flooding during establishment.….
2.11Farmer’s coping Strategies to flood ……………………………
CHAPTER THREE
3.0 MATERIALS AND METHOD …………………………………………….
3.1 Area of study ………………………………………………………………..
3.2 Material ……………………………………………………………………………
3.3 Germination Determination …………………………………………
3.4 Yield of various Varieties …………………………………………….
3.5 Land preparation
3.6 Method …………………………………………………………………………
CHAPTER FOUR
4.0 RESULTS AND DISCUSSION…………………………………………..
4.1 Results ………………………………………………………………………….
4.2 Discussion ……………………………………………………………………..
CHAPTER FIVE
5.0 CONCLUSION AND RECOMMENDATION……………………………
5.1 Conclusion ……………………………………………………………………….
5.2 Recommendation ………………………………………………………….
References……………………………………………………………………
INTRODUCTION
The damaging effects of flooding remain as major sources of concerns among millions of rice farmers worldwide. The weather change due to various reasons causing unexpected and sudden flood recently in Nigeria has negative impacts on rice farming and people’s life. This research project is to evaluate the effect of flooding on the growth of three varieties of rice grown in Abakaliki Ebonyi State and to see how it influences people and agriculture.
The extent of the damage of flooding on rice is related to at least three factors. The temperature of the water, the amount of water motion and the duration of the flood. Temperature affects the speed of respiration. The faster the respiration, the quicker the oxygen is depleted and the sooner fermentation begins. Warm water speeds respiration, oxygen use and cell death. The faster water moves the greater the degree of turbulence. This water turbulence oxygenates the water slightly. Increasing oxygen content of the water slightly decrease’s the impact of flooding on plants. Duration of the flood is important because many of the effects of low oxygen on plants are reversible of the duration is not too long. Long durations allow for increased oxygen depletion and build up of harmful chemicals. Although local conditions influence the effects, 36 to 48 hours is often the tolerable limit.
In general rice cannot tolerate flooding better than other plants. But, if flooding occurs in the spring, the rice growing point is near the soil surface (below or above) making it likely to be submersed longer. Soil water logging and submergence (collectively termed flooding) are abiotic stresses that influence species composition and productivity in various type of rice, worldwide.
In rice farming, flooding species are manipulated (e.g. Ofada, upland and Nerica rice) or are accommodated by genotype selection. There have also been recent advances towards developing cultivators for low land areas prone to short-duration flash flooding. For most of this rice, excess water is a constraint to growth and productivity in many regions and this adversely affecting the growth of various types of rice.
Finally, rice are often damaged and thus, more susceptible to disease organisms. Disease symptoms may not appear until several weeks or even months after the flood event.
