不同营养盐条件对琼枝生长的影响

Effects of different nutrient conditions on the growth of Betaphycus gelatinae

中文关键词: 琼枝  营养盐  生长  色素

英文关键词: Betaphycus gelatinae  Nutrient  Growth  Pigment

中文摘要:

      本研究分别测定了不同无机氮浓度(50、100、200、400和800 μmol/L)、不同无机磷浓度(2.5、5、10、20、40和80 μmol/L)和不同氨氮(NH4+-N)、硝酸盐氮(NO3–-N)浓度比(0/100、25/75、50/50、75/25和100/0)培养条件下,琼枝(Betaphycus gelatinae)生长及色素含量的变化，评估适合其生长的营养盐条件。结果显示，适合琼枝生长的无机氮浓度为0~200 μmol/L，无机磷浓度为2.5~ 10 μmol/L，NH4+-N/NO3–-N浓度比为25/75。在适宜的营养盐条件范围内，琼枝生长状态较好，具有较高的增重率；而当无机氮浓度超过200 μmol/L、无机磷浓度超过10 μmol/L或NH4+-N/NO3–-N浓度比高于50/50时，培养初期，琼枝生长缓慢，具有一定的耐受能力，但培养时间过长，不利于琼枝正常生长，引起藻体白烂严重、增重率急剧下降。本研究表明，琼枝适合在低营养盐环境下生长，结果可为琼枝规模化增殖栽培提供理论基础。

英文摘要:

      In this study, we measured the growth and pigment content of Betaphycus gelatinae under different inorganic nitrogen concentrations (50, 100, 200, 400, and 800 μmol/L), inorganic phosphorus concentrations (2.5, 5, 10, 20, 40, and 80 μmol/L), and different ratios of NH4+-N and NO3–-N (0/100, 25/75, 50/50, 75/25, and 100/0). The best nutrient conditions for the growth of B. gelatinae were thus evaluated. The results showed that the optimum nutrient conditions for the growth of B. gelatinae were an inorganic nitrogen concentration of 0~200 μmol/L, inorganic phosphorus concentration of 2.5~10 μmol/L, and NH4+-N to NO3–-N ratio of 25/75. Within the range of suitable nutrient conditions, B. gelatinae achieved high weight gain. When the inorganic nitrogen concentration exceeded 200 μmol/L, inorganic phosphorus concentration exceeded 10 μmol/L, or the ratio of NH4+-N to NO3–-N was higher than 50/50, the growth of B. gelatinae was slow but tolerance to adverse growth conditions was observed at the beginning of cultivation. However, with the extension of culture time, the growth of B. gelatinae became abnormal; severe white rot of algal bodies and a sharp decrease in weight gain was observed. Overall, our findings indicate that B. gelatinae grows faster under relatively low nutrient conditions and provide a theoretical basis for large-scale multiplication cultivation of B. gelatinae.