【作者】 李晓；

【导师】 段德麟；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋生物学， 2009， 硕士

【摘要】 角叉菜(Chondrus)是一种重要的经济红藻,广泛应用于食品行业及卡拉胶的提取工业。从种苗繁育的角度看,对角叉菜早期发育的研究意义重大。自然环境下角叉菜的生活史循环已得到阐释,但对其四分孢子及果孢子在室内条件下的早期发育过程还远远了解不够,因此有必要对其早期发育的具体特征和影响因素进行详细的分析研究。本研究以青岛海域常见的角叉菜(Chondrus ocellatus Holm)作为实验材料,分析了实验室培养条件下温度及光强两个环境因子对其四分孢子和果孢子早期生长发育的影响,同时对整个发育过程进行了观察与记录。研究结果表明角叉菜两种孢子的早期生长发育过程基本一致,从孢子附着后萌发到长出幼苗,整个过程经历三个发育阶段:分裂期、盘状体期和直立幼苗形成期。另外,在早期发育过程中观察到多个盘状体融合的现象,这种融合使得孢子幼苗对基质的附着更加稳固,有利于其生存。通过设定6个温度梯度(10℃、15℃、20℃、22℃、25℃、28℃)及2个不同光照强度(10、60μmol photos m-2s-1)条件,确立了角叉菜果孢子及四分孢子最适培养温度为20℃,而最适光照强度为60μmol photos m-2s-1。角叉菜四分孢子和果孢子的早期生长发育均显示出较宽的温度耐受范围(10-25℃),但在28℃的高温条件下,两种孢子均会逐渐褪色死亡。分别采用单因素方差分析和独立样本t检验两种统计学方法分析温度和光强的影响,发现温度、光强的变化对角叉菜盘状体生长均有显著性影响。高光照可促进两种孢子的生长与发育,而低温(10℃)则会抑制孢子的的生长与发育。更多还原

【Abstract】 Chondrus is one of the commercial red seaweeds widely used for food and carrageen production. The early development is crucial for the seedling nursing. Natural cycle of the algal life history is well understood, but the properties of development of tetraspore and carpospore are still very poorly known. It is therefore necessary to understand the physiological influences on its early development. Here in our study, the thalli of C. ocellatus Holm were collected from the natural habitants in Qingdao, China, from Oct. to Dec. 2008. The effects of temperature and irradiance on the early development of C. ocellatus tetraspores and carpospores under laboratory conditions were conducted, and meanwhile the properties of development process was observed and recorded. It is showed that there are no obvious differences existing between the early development of tetraspores and carpospores, and the development can be regarded as three stages: division stage, discoid crust stage and seedling stage. Besides, the coalescences of two or three discoid crusts during the early development were observed, which enhanced the adhesion of sporelings to the substrates. The released tetraspores and carpospores were cultivated at 6 different temperatures (10°C, 15°C, 20°C, 22°C, 25°C, 28°C) and two irradiances (10, 60μmol photos m-2s-1) with a photoperiod of 12:12h (L:D). It was showed that the optimal temperature suitable to the early development of C. ocellatus Holm is 20°C, and a maximum growth rate occurred above 60μmol photos m-2s-1. Both tetraspores and carpospores showed a wide tolerance to temperature from 10-25°C, but too high temperature of 28°C will lead to the death of tetraspore and carpospore. According to statistic analysis by means of one-way ANOVA and independent-samples t test, the variations of temperature and irradiance significantly affected discoid crust growth. High light intensity significantly accelerated growth and development. Low temperature of 10°C retarded the growth and development.更多还原