EVALUATION OF THE EFFECTS OF FLOODING ON THREE VARIETIES OF RICE (A CASE STUDY OF ABAKALIKI, EBONYI STATE)
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.
