<div style="text-align: justify;">Saprolegnia parasitica infecting Rainbow trout (Oncorhynchus mykiss), has been a major bottleneck in the intensification and propagation of trout culture in northern Himalayas of India. Present study was to ascertain the presence of S. parasitica infections using molecular diagnostic techniques in cultured rainbow trouts collected from different hatcheries of Kashmir valley. Growth of S. parasitica at different incubation temperatures was examined. The molecular detection of fungus done by using PCR, revealed that the twenty trout specimens out of 144 collected samples were found infected with Saprolegnia parasitica with overall prevalence of 13.88%, with a PCR product size of around 750 bp. No growth of S. parasitica was reported at 4&deg;C after 48 h of incubation. S. parasitica infections were more frequent in cold water months when water temperature was recorded between 7&deg;C &ndash; 9&deg;C.</div>

<div style="text-align: justify;">PCR Based Identification of <em>Saprolegnia parasitica</em> Affecting Rainbow Trout Aquaculture in Kashmir Region of Indian Himalayas</div>

<p style="text-align: justify;">An attempt has been made to isolate the pathogenic fungus from water, body tissue of cold water fish. The hemp seed culture was applied to obtain the fungal colonies and bacteria free pure isolate was obtained by repeated subcultures, using SDA (Sabouraud Dextrose Agar) under aseptic condition and allowed to incubate at 18-200C for 48 hours. Fungal infection was more prominent in the ponds of stagnant water than the running water raceways. The inferior water quality of the stagnant fish ponds supports the virulence of the fungus spores. The muscles of the rainbow trout, fins and gills of the carp were susceptible for the infection. Intensity of the infection in cold water fish species increases with the downfall of the water temperature. The pathogenic fungi in the present study was identified as Saprolegnia parasitica, Saprolegnia diclina and S. ferax with cotton like appearance, elongated zoosporangia and pear shaped primary sporangium.&nbsp;</p>


PCR Based Identification of Saprolegnia parasitica Affecting Rainbow Trout Aquaculture in Kashmir Region of Indian Himalayas

Isolation of pathogenic fungi from the major cultivated coldwater fish species and their environment in the kumaon region of Uttrakhand