LIPID-COMPOSITION OF CYST STAGES OF GLOBODERA-ROSTOCHIENSIS

Lipid compositional analysis was conducted on the white, yellow, and b rown cyst stages of Globodera rostochiensis (golden cyst nematode). Tr iacylglycerols were the largest lipid fraction in all stages examined, ranging from 55-75% of total lipid. Ethanolamine phosphoglycerides an d choline phosphoglycerides were present in high amounts in all cyst f ractions, with a total phospholipid content of 20%, 14.7%, and 12.8% i n the white, yellow, and brown cyst stages, respectively. Sterols, ste ryl esters, sphingomyelin, and cardiolipin were found in minor amounts in all three cyst stages and showed greater changes than other classe s of lipids relative to cyst stage. The fatty acid compositions of the three cyst stages were similar. Eicosenoic acid (20:1) and arachidoni c acid (20:4) were found in higher concentrations than other fatty aci ds in all cyst preparations; vaccenic acid (18:1) occurred at the thir d highest concentration. More than 78% of total fatty acids were unsat urated at all cyst stages, and more than 60% were of C20 or longer cha in length. The lipid profile of all three cyst stages is consistent wi th invertebrate adaptation to low-temperature environments.