Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea sur...Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea surface temperature, salinity, p H, total alkalinity, dissolved oxygen and nutrients like nitrate, nitrite, inorganic phosphate and reactive silicate, chlorophyll a and phytoplankton assemblages were studied for a period of five months(May, August, September 2010, March and November 2011). Over 121 species of phytoplankton represented by 93 species of diatoms, 16 species of dinoflagellates, 9 species of blue-green algae, 2 species of greens and 1 species of silicoflagellate were recorded. High phytoplankton species diversity was found in March 2011 when salinity and nitrate concentrations were low and reactive silicate and inorganic phosphates were moderate. Species diversity was low during May 2010 when increased sea surface temperature, salinity and low nutrients availability were observed. Coscinodiscus centralis, Diatoma vulgaris and Proboscia alata were dominant, especially Coscinodiscus sp. distributed in all stations whereas Skeletonema costatum, Odontella sinensis and Ditylum brightwellii were abundant in August and September 2010. From principal component analysis and multiple regression analysis, it is evident that variables like sea surface temperature and dissolved oxygen are the most important factors influencing the seasonal pattern of phytoplankton population.展开更多
Objective:To ascertain the feasibility of using sustainable natural resources in maintaining disease free fish in such establishments.Methods:causative bacteria were identified by morphology and biochemical techniques...Objective:To ascertain the feasibility of using sustainable natural resources in maintaining disease free fish in such establishments.Methods:causative bacteria were identified by morphology and biochemical techniques.The antibacterial activity and disease resistant capability of mangrove plant leaf extract were investigated against fish pathogens.Results:The infected marine ornamental fishes were collected from the hatchery condition and inhibition activity at the concentration of 220,200,175 and 150μg/mL against Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus,and Vibrio anguillarum respectively.The experimental trial reveals feeding marine ornamental fish with feed incorporated with a methanol leaf extract of Avicennia marina,increases their survival and reduces their susceptibility to infections from the isolated bacteria.Based on the in vitro assay,methanol extract of Avicennia marina was exhibited good Conclusions:The mangrove leaves have potential to control the infections caused by Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus and Vibrio anguillarum.展开更多
基金the University Grants Commission,Govt.of India,New Delhi for financial support through UGCResearch Award(No.F.30-1/2014(SA-II)/RA-2014-16-SCTAM-4364 dated 05/02/2015)
文摘Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea surface temperature, salinity, p H, total alkalinity, dissolved oxygen and nutrients like nitrate, nitrite, inorganic phosphate and reactive silicate, chlorophyll a and phytoplankton assemblages were studied for a period of five months(May, August, September 2010, March and November 2011). Over 121 species of phytoplankton represented by 93 species of diatoms, 16 species of dinoflagellates, 9 species of blue-green algae, 2 species of greens and 1 species of silicoflagellate were recorded. High phytoplankton species diversity was found in March 2011 when salinity and nitrate concentrations were low and reactive silicate and inorganic phosphates were moderate. Species diversity was low during May 2010 when increased sea surface temperature, salinity and low nutrients availability were observed. Coscinodiscus centralis, Diatoma vulgaris and Proboscia alata were dominant, especially Coscinodiscus sp. distributed in all stations whereas Skeletonema costatum, Odontella sinensis and Ditylum brightwellii were abundant in August and September 2010. From principal component analysis and multiple regression analysis, it is evident that variables like sea surface temperature and dissolved oxygen are the most important factors influencing the seasonal pattern of phytoplankton population.
基金Supported by University Grants Commission(UGC),New Delhi for providing the financial assistance.Reference No.U.G.C.No.33-384/2007(SR).
文摘Objective:To ascertain the feasibility of using sustainable natural resources in maintaining disease free fish in such establishments.Methods:causative bacteria were identified by morphology and biochemical techniques.The antibacterial activity and disease resistant capability of mangrove plant leaf extract were investigated against fish pathogens.Results:The infected marine ornamental fishes were collected from the hatchery condition and inhibition activity at the concentration of 220,200,175 and 150μg/mL against Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus,and Vibrio anguillarum respectively.The experimental trial reveals feeding marine ornamental fish with feed incorporated with a methanol leaf extract of Avicennia marina,increases their survival and reduces their susceptibility to infections from the isolated bacteria.Based on the in vitro assay,methanol extract of Avicennia marina was exhibited good Conclusions:The mangrove leaves have potential to control the infections caused by Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus and Vibrio anguillarum.
