Lipid Metabolic Profile Interrelationships between the Silkworm(Bombyx mori L.)and Its Host Plant(Morus)Varieties

The lipid content and composition in tender, medium and coarse leaves of 3 mulberry varieties were analyzed. Tender leaf contained more lipid than medium and coarse leaves. Fatty acid composition of lipids also varied with leaf maturity. Tender leaf contained more precursor fatty acids, medium leaf more unsaturated fatty acids and coarse leaf more saturated fatty acids. V-1 mulberry variety had more foliar lipid con- tent than S-36 and M-5. Lipid composition also varied among the 3 mulberry varieties. V-1 and S-36 leaves contained more unsaturated fatty acids and M-5 more saturated fatty acids. V instar silkworm was fed with the medium leaf of the 3 mulberry varieties, and the total lipid content and fatty acid composition of the haemolymph, fatbody and excreta were analyzed. Lauric acid （12：0）, undetectable in the haemolymph, was recovered in significant quantity in the excreta. Saturated fatty acids （16：0 and 18：0） were higher in the haemolymph of larvae fed on M-5 while unsaturated fatty acids （18：2 and 18：3） were higher in those fed on S-36 and V-1 leaves. But, the percentage levels of 18：1 and 18：2 fatty acids in the leaf and haemolymph were swapped. While the leaf of M-5 mulberry variety had 18：1 and 18：2 fatty acid components at 1.93% and 16.8%, the larvae feeding on the leaf had 18：1 and 18：2 at 21.5% and 6.95% in the haemolymph. Similar correction in the percentages of the two unsaturated fatty acids was observed in the larvae feeding on the leaves of S-36 and V-1. Saturation of co -6 double bond of linoleic acid by a reductase in the lower end of the midgut was proposed.

桑叶营养对家蚕血淋巴阳离子水平的调节作用(英文)

调查了取食不同品种桑树(M-5,S-36和V-1)叶片的家蚕(多化性品种Pure Mysore、二化性品种NB4D2和CSR2)5龄幼虫血淋巴中阳离子的变化。结果表明:家蚕幼虫血淋巴中Na+浓度低,K+和Mg2+浓度很高,Ca2+浓度较高。在幼虫活跃取食期间,血淋巴中阳离子水平显著提高。血淋巴中阳离子水平与排泄物的量呈负相关。血淋巴中阳离子水平受阳离子外泌的控制。与非取食阶段相比,取食阶段的阳离子清除速率低。家蚕二化性品种的血淋巴阳离子水平比多化性品种PM高出30%。结果说明家蚕品种对家蚕血淋巴阳离子变化的影响显著大于桑树品种或家蚕个体发育的影响。