生态因子对萱藻(Scytosiphon lomentaria)孢子体生长发育的影响

摘要

采用实验生态学方法,研究了温度、光照、营养盐(N、P)对萱藻孢子体生长发育的影响.结果表明,在5-23℃范围内,温度越高,越有利于萱藻孢子体的生长.9-17℃是比较利于孢子囊产生的温度范围,其中13 ℃,L:D=10:14,20μmol/(m<'2>·s)条件下最有利于孢子囊的形成与孢子的放散.光强6-30μmol/(m<'2>·s)利于孢子囊的形成.短日照条件下(≤12h)利于孢子囊的产生,长日照条件(>12h)尽管温度适宜,但仅利于孢子体的营养生长.萱藻丝状体生长的最适N、P元素浓度分别为40mg/L、8mg/L.%Scytosiphon lomentaria (Lyngbye) Link attach to phaeophyta, which distributes along the coastal areas from the Liaodong Peninsula to the Hailing island of Guangdong province, with a life cycle of alternation of heteromorphic generations.The erect thallus, also called gametophyte, is macro generation and sporophyte is its micro generation of life history including filaments, crustose or cushion-like thalli.The culture techniques and development of S.lomentaria depend on the well studies of its growth and development properties.This paper focused on the growth and development of sporophytes at different temperatures, light and nutrient conditions.Zygotes germinated at 5-28℃, 10-30μmol/(m2·s),and light periods less than 14h.The suitable temperatures for the growth of sporophytes were 5-23℃ and the optimum temperatures were 20-23℃.The suitable temperatures for the formation of sporangia were 9-17℃ and the optimum condition was 13℃, L: D 10: 14, 20μmol/(m2·s).Temperature over 30℃ inhibited the germination and growth of zygotes (about 80％ of them died after one week).At higher temperature (≥26℃), crustose or cushion-like thalli were the main form while filaments and cushion-like thalli were the main forms of sporophytes at lower temperature (＜26℃).Increase of light intensity promoted the growth of sporophytes.The suitable light intensities for the formation of sporangia were 6-30μmol/(m2·s).When the light period was less than 12h, it was suitable for formation of sporangia.Whereas,when the light period was more than 12h, it was suitable for the growth of sporophytes.The optimum concentrations of nitrogen and phosphorus element for the growth of S.lomentaria filaments were 40mg/L and 8mg/L, respectively.