摘要
在低氮海水中培养龙须菜(Gracilaria sjoestedtii Kylin),采用间歇施肥法控制藻体氮营养状态并通过化学组分分析研究了藻体内含氮化合物和碳水化合物的变化,探讨了它们之间的相互关系。试验结果表明:施肥的藻体保持较高的生长速度和较高的总氮、蛋白质和游离氨基酸含量。在氮饥饿状态下,藻体内红藻糖苷含量增加显著;随着氮饥饿程度的增加,红藻淀粉的含量增加;在氮饥饿后期,半乳聚糖的累积最明显。当外界氮供应发生变化时,红藻糖苷和游离氨基酸含量的变化最显著,这两种化合物的含量变化存在着明显的负相关(r=-0.98,p<0.005)。
Effect of ammonium-nitrogen on growth and chemical composition of Gracilaria sjoeste-dtii Kylin was investigated. The nitrogen starved plants were fertilized intermittently with 10 mol/L NH4-N for 1 h at 3 day intervals. The results are as follows:(1) The growth rate and yield were high in the plants fertilized intermittently.(2) After nitrogen fertilization, the contents of free amino acids, especially those of gluta-mate, aspartate and arginine, increased obviously. In the nitrogen starved plants, the low molecular weight carbohydrate, floridoside, increased distinctly. This suggests that the levels of free amino acids and floridoside would easily be affected by the fluctuation of nitrogen available. The contents of total nitrogen, protein and free amino acids have reverse relationship with the contents of carbohydrate.(3) Different saccharide components increased in varying degrees in nitrogen starved plants. At initial stage of nitrogen starvation, the accumulation of floridoside increased prominently. Afterwards the accumulation of floridean starch predominated. In later period of nitrogen starvation, the accumulation of galactan was accelarated, suggesting the increase of phycocolloid content. The halting of nitrogen fertilization prior to harvesting should increase the content of phycocolloid in cultivated Gracilaria sjoestedtii.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
1989年第6期493-501,共9页
Oceanologia Et Limnologia Sinica
