The Life History Of Perkinsus Beihaiensis And The Influence Of Physical Factors On Its Life History

Perkinsus beihaiensis was first discovered as a new Perkinsus sp.in the southern sea area of China,and it is widespread in Chinese coastal sea.Perkinsosis ccurred at almost all of coastal waters in the world,causing rather high mortality of shellfish.However,the internationally-accepted method of cultivating Perkinsus has the disadvantages of time consume and slow proliferation,which seriously hinders the development of downstream experiments such as artificial infection of Perkinsus.On the basis of our early preliminary Perkinsus cultured experiments using by liquid thioglycolate culture medium(RFTM),we further studied the complete life history of P.beihaiensis and its morphological variaition in different life histories..This study aimed at the in vitro culture of P.beihaiensis with the combinations of three factors(temperature,salinity,shocking),exploring the effects of the physical factors variation on P.beihaiensis reproduction.It laid the foundation for the future research of P.beihaiensis,especially in vitro culture.ARFTM medium and DME / F12 medium was used to culture P.beihaiensis cells in vitro to investigate the specific in vitro life history of P.beihaiensis.The result indicated that in addition to trophozoites,hypnospore and zoospore,the life history of P.beihaiensis included a pre-zoocystic stage.This stage occurred after hypnospore stage of P.beihaiensis.In this stage,P.beihaiensis reproduce the spores mainly by budding,and the reproduction was very rapid but the cell volume is small.In order to make the reproduction of P.beihaiensis faster in vitro,we used physical conditions such as temperature,salinity and shock to stimulate.Through experiments,we found that under normal temperature,salinity and no added shock conditions,P.beihaiensis grew fastest at 28 ℃ and 25 salinity,and began to multiply exponentially within 20 days.When both of the temperature and salinity decrease from the higher conditions at the same time,it will have a positive effect on the reproduction of P.beihaiensis and began to exponentially multiply in 8 days.At the same time,we found that when only one variable of the concussion condition was added,P.beihaiensis began to exponentially multiply in 12 days.