IJSRP, Volume 4, Issue 5, May 2014 Edition [ISSN 2250-3153]
The research was carried out to minimize nitrate leachate in RBE soil by in cooperating green manures (Sesbania rostrata, Gliricidia and sunhemp) and Azolla. The soil samples for experiment was collected from non agricultural lands in Thavashikulam, Vavuniya. Experiment was carried out with RCBD with six treatments such as Control(T1), Urea (T2), Sun Hemp (T3) Azolla (T4) ) Gliricidia (T5) and Sesbania rostrata (T6), and three replicates. The results were analyzed by ANOVA for a Random Complete Block design (RCBD) to determine significance of differences (P>0.05) between the treatments. Duncun mean comparison was carried out by using SAS package. Nitrate losses were significantly (P=0.022) differ from each treatments and highest amount of loss was observed in Azolla (19.66mg) followed by Urea(17.54mg), sespania (15.34), Giliricidia ( 13.14)and sunhemp( 11.2 ). Nitrate losses were less in green manure(Sesbania, Sunhemp & Gliricidia) added soil than inorganic fertilized (urea) soil with in one month period. Green manures ( Sesbania, Sunhemp and Giliricidia) could be utilized to minimize nitrate loses in RBE soil except Azolla. Azolla could be used as bio fertilizer in wet land paddy soil as it is considered as super plant to fix atmospheric nitrogen (5-6% of nitrogen) and Nitrate loss was higher in Azolla than urea in RBE soil. The field study could be carried out to confirm the finding to implement the findings in farmers field.