Summary of Abstract Submission

Abstract Submission No. IO50-09-0068PresentationPoster

IMPACT OF UPWELLING ON VIRAL DYNAMICS IN THE UPWELLING AREAS OFF ALLEPPEY, SOUTH WEST COAST OF INDIA

Jasna V*1, Parvathi A1, Aparna S 1, Aswathy AJ 1

1 National Institute of Oceanography, India

ABSTRACT :

Viruses have been identified as a key component of aquatic microbial communities because of their abundance, ubiquity and potential impact on bacterial and phytoplankton hosts. However, the ecology of virus is poorly documented in the Indian waters, especially in response to upwelling. We evaluated the response of bacteria and viruses in the coastal waters of Alleppey during upwelling period. Observations were carried out on the abundance of virus, bacteria, burst size and frequency of infection. The abundance of virus, total bacteria and viable bacteria were in the order of 106 particles ml-1. 105 ml-1 and 104ml-1 respectively. Their abundance increased by 20-25% during periods of upwelling. There was a sudden decrease in the abundance of sediment attached bacteria, indicating the suspension of sediments in the water column during upwelling. However, the percentage of visibly infected cells was low presumably because of the unfavourable local environmental and climatic conditions. The viral to bacterial ratio was low during upwelling indicating weak viral processes or a short persistence of viruses due to less hospitable physical conditions that limit the ability of viruses to find new hosts. Our study gives a first insight on various viral groups affecting the different bacterial morphotypes during upwelling.