PARENT GROUPER REARING,SPAWNING,FERTILIZATION AND EMBRYONIC DEVELOPMENT OF EPINEPHELUS MALABARICUS(BLOCH SCHNEIDER)

million fries of Epinephelus malabaricus(Bloch Schneider)over 3cm of total length were produced in concrete tanks before June 30,2002.Parent groupers composed of artificial sex-reversed functional male,natural male and female.The paper reported part of results from above protocol as follows:1)Parent grouper cultured strenuously spawned in a natural way,the average fertilization rate was 81%,the highest was 97%;2)The head of spermatozoon from functional male is in the shape of ball,spermatozoon head diameters range about from 3.7-6.1m,caudal length 12.4-44.5m,and the longest swimming time of spermatozoon is over 35min.,the time of stopping swimming of 90% of all spermatozoa 31min.under conditions of water temperature 26℃,salinity 3%,pH7.9.These indicated that artificial sex-reversed functional male is not different from natural male,as a resource of male parent grouper in artificial propagation;3)The spawning period is from early April to middle November,the most spawning appears mainly from late April to late May or from late September to early October.Natural spawning continues to the second day 1:30 from 16:40 in a day; 4)The spawning usually occurs under condition of water temperature was 23.5-28.6℃,but is restrained when water temperature above 28.6℃ or below 23.5℃,and even almost stops above 30℃ or below 21℃.The most optimum water temperature is 25.5℃-26.5℃.;5)When water temperature was 26℃,fertilized eggs are partially buoyant under condition 2.82%-2.96% in salinity,as sinking below 2.82% in salinity and floating above 2.96% in salinity;6)The embryonic development is 21h.under the water temperature of 24.9-27.6℃,3%-3.3%,in salinity pH 7.6-8.2,and the present study has given complete phases of embryonic development.