Abstract:

The effect of different ratio of organic and inorganic nitrogen fertilizers on the growth, nutrition, as well as yield of crabs was investigated when these fertilizers was applied for once under a symbiosis system composed of paddy and crab. Comparing to conventional famer practice (FP) and optimum fertilization (OPT), treatment A1 (balanced fertilization) had a satisfied result on the growth, as well as the yield and quality of crab. The contents of protein, fat and moisture in edible part of crabs were 20.3%, 6.3% and 72.0% respectively. At the same time, the yield of paddy was the highest with number of 11002.5kg/hm2. The survival rate of crabs was as high as 66.7%, which could satisfy the demand of agricultural production.As far as OPT treatment was concerned, it seemed more suitable for paddy instead of crabs.