ON- STATION EVALUATION OF GROWING PERFORMANCE OF FIVE STRAINS OF NILE TILAPIA

Seventeen experiment s have been conducted to study the growing per formance o f 5 st ra ins o f Nile t ilapia, including GIFT st ra in, / 780 st ra in, / 880 st ra in, / Egypt0 str ain and / American0 str ain, cultur ed in net-cages, co ncrete tanks and ea rthen po nds pr acticed w ith e ither po lyculture o r mo noculture sy stems in Qingdao o f Yellow Riv er basin, Shangha i and Huzhou of Yangt ze Riv er basin and Guangzhou of Pear l River basin. The three basins represent the majo r a gro-ecosy stems of China. Major results show ed, r eg ardless o f the str ains cultured in what ag ro-ecosystems or culture sy stems, f r om f inger ling to adult stage, the r anks of grow ing r ate w ere GIFT st ra in > / 880 st rain > / 780 str ain > / American0 str ain > / Egy pt0 str ain. The pheno type-envir onmental inter actio n w as not found in the va riat ions of grow ing r ate of dif ferent st rains of the Nile t ilapia.