Fatty Acid Composition of Eight Isolates of Entomopathogenic Nematodes from Five Egyptian Governorates

The
fatty acid composition of infective juveniles (IJs) related to five isolates of
Heterorhabditis indica (EGAZ1, EGAZ2, EGAZ3, EGAZ4, and EGAZ5) and three
isolates of Steinernema carpocapsae (EGAZ9, EGAZ10 and SA)
collected from five Egyptian Governorates was assessed. Also, fatty acid
composition of IJs from two commercially relevance strains of H.
bacteriophora (HP88)and S. carpocapsae (All), was examined
for comparison. Newly emerged IJs of all isolates had fatty acid number and
pattern similar to that of the corresponding commercial species. Of the ten
fatty acids identified, oleic, was the main fatty acid in all species and
isolates. Unsaturated fatty acids were dominant and total amount of saturated
fatty acids of H. indica isolates was significantly higher than that of S.
carpocapsae isolates. Palmitic was the second most abundant fatty acid
in IJs of H. indica isolates, while linoleic was the second most
abundant fatty acid in IJs of S. carpocapsae isolates. Of
the tested Egyptian isolates, IJs of EGAZ3 and EGAZ5 of H. indica had
the highest amounts of fatty acids and their contents of saturated fatty
acids/gram body weight are comparable to that of the commercial strain. It is suggested that isolates EGAZ3 and EGAZ5
of H. indica are the candidates for developing practical Egyptian
bio-control product based on nematode formulation.