THE LIPID-CONTENT AND FATTY-ACID COMPOSITION OF HATCHED 2ND STAGE JUVENILES OF GLOBODERA-ROSTOCHIENSIS AND GLOBODERA-PALLIDA

Globodera rostachiensis and G. pallida hatched (1-day-old in potato ro ot diffusate) second stage juveniles (J2) contained 29.2 % and 27.2 % lipid (of dry weight), respectively. Globodera rostochiensis J2 lipid consisted of 72.8 % neutral lipid, 11.3 % free fatty acids and 15.9 % non-acetic phospholipid. The neutral lipid fraction comprised 95.5 % t riacylglycerides, 1.8 % diacylglycerides, 2.3 % monoacylglycerides and 0.4 % cholesterol ester. Globodera pallida J2 lipid consisted of 73.0 % neutral lipid, 13.2 % free fatty acids and 13.8 % n.-a. phospholipi d. Total unsaturated fatty acids comprised 77.4 % and 80.6 % of total lipid in G. rostochiensis and G. pallida, respectively. The two specie s showed similar fatty acid profiles. Twenty fatty acids were identifi ed, ranging from C14 to C22; the major lipid classes were composed pre dominantly of C20 (50-60 %) and Cls (30-35 %) fatty acids. The three m ost abundant fatty acids found in both species were C20:4, C20:1 and C 18:1, making up more than 60 % of the total. Globodera rostochiensis J 2, which had hatched over 24 h periods during the first 2 weeks exposu re to potato root diffusate, had the same fatty acid composition as th ose which hatched over 96 h periods in weeks 3 and 4.