Grateloupia turuturu is a commercial red alga with potential value in nutraceuticals and pharmaceuticals. To supplement information on its life history and verify whether carpospores can be used for seedling culture, ...Grateloupia turuturu is a commercial red alga with potential value in nutraceuticals and pharmaceuticals. To supplement information on its life history and verify whether carpospores can be used for seedling culture, early development of G. turuturu was investigated under culture conditions (27°C, 10-13 mol/(m2.s) in irradiance, photoperiod 10:14 h L:D). Three physiological stages were recognized by continuous microscopic observation: division stage, discoid crust stage, and juvenile seedling stage. At the beginning of the division stage, the carpospores developed germ tubes into which the carpospore protoplasm was evacuated, and then the carpospore protoplasm in the germ tubes began to divide continuously until discoid crusts formed. Finally, upright thalli appeared on the discoid crusts and developed into juvenile seedlings. It took about 60 days for carpospores to develop into juvenile seedlings. The growth parameters, including germination rate for carpospores and discoid crust diameter, were recorded. These results contribute more information on the life cycle, and at the same time are of great significance in the scaling-up of artificial seedling cultures of G. turuturu.展开更多
Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development o...Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedling nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study, we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures (10–28°C) and irradiances (10, 60 μmol photons m-2s-1) with a photoperiod of 12L:12D. The results indicate that both tetraspores and carpospores are tolerant to temperatures of 10–25°C, and have the highest relative growth rate at 20°C. Irradiance variances influenced the growth of the discoid crusts, and the influence was more significant with increasing temperature; 60 μmol photons m-2s-1 was more suitable than 10 μmol photons m-2s-1. The optimum temperature and irradiance for the development of seedlings was 20°C and 60 μmol photons m-2s-1, respectively.展开更多
Costaria costata(C.Agardh) Saunders is one of common kelps distributed in many coastal areas worldwide;however,in China,no reports have been made on cultivation of the genus.To investigate potential cultivation of the...Costaria costata(C.Agardh) Saunders is one of common kelps distributed in many coastal areas worldwide;however,in China,no reports have been made on cultivation of the genus.To investigate potential cultivation of the species in the northern part of China,trials on isolation and preservation of the gametophytes were conducted using C.costata from Korea;growth and development of the gametophytes were observed.We showed that at 10±1°C,60 μmol m-2s-1 and 12:12 h(L:D),freshly released zoospores settled down within 1 hour,and then developed into the primary cell during the following 2 days.After a vegetative growth phase lasting 6-8 days,female gametophytes became 3-4 times larger in diameter than that of the primary cell,but still remained at a unicellular stage,while male gametophytes divided into 4-10 cells with only a slight change in size.Fertilization occurred within 10 days after the zoospores were released from the sporangia,and the apical and basal tissues of the juvenile sporophyte divided and differentiated into the blade and stipe.Temperature and irradiance influenced gametophytic vegetative growth and developmental patterns.Generally,low irradiance(15 μmol m-2s-1 and 30 μmol m-2s-1) was unfavorable to the induction of fertility,but it enhanced female gametophyte division.The optimal conditions for vegetative growth were 15°C and 30 μmol m-2s-1.After transplantation of the juvenile seedlings and after eight months cultivation,the harvested mature blade reached 194 cm in length and 32.7 cm in width.Our study proves that it is feasible to implement propagation and large scale cultivation of C.costata in northern China.展开更多
文摘红藻真江蓠(Gracilaria vermiculophylla)是西北太平洋地区特有种,但在过去100年间它借助海运(太平洋牡蛎养殖)快速入侵到北美、欧洲和地中海等沿海栖息地,对当地的生物多样性、海洋环境和生态系统等造成重大影响。为从分子水平初步了解真江蓠成功入侵的潜在机制,文章对其入侵起源地——日本北部的真江蓠及非入侵种——绳状龙须菜(Gracilariopsis chorda)进行了同质园实验(common garden experiment)处理后的比较转录组研究,以探究该地区入侵属性不同的两种红藻间的基因表达差异。结果表明,真江蓠和绳状龙须菜共有基因序列集(Universal Gene,unigene)主要集中在核糖体、嘌呤和嘧啶代谢等通路。其中,在真江蓠中光系统II反应中心蛋白D1(photosystem II reaction center protein D1)、细胞色素P450单加氧酶(cytochrome P450 monooxygenase)和核酮糖1,5二磷酸羧化酶大亚基(Ribulose bisphosphate carboxylase large subunit,rbcL)等基因的表达量显著上调,而逆转录转座子蛋白(retrotransposon protein)、细胞壁相关的水解酶(cell wall-associated hydrolase)和金属离子转运蛋白Nramp5的表达既上调也下调。与光合作用过程相关基因的大量表达可能有助于真江蓠应对逆境胁迫,特别是光系统ⅡD1反应中心蛋白表达量升高可能有助于藻体修复光系统Ⅱ复合体,从而制造更多的有机物以备藻体生长所需。而金属离子转运蛋白Nramp5等的上调和下调则表明江蓠等红藻可能通过某些基因表达量的增减对不同的环境变动作出响应。总体而言,代谢过程中的资源再分配很可能是驱动真江蓠适应和耐受新的生境的主要分子机制。
基金Supported by the Natural Science Foundation of Shandong Province,China(No.Y2007D42)
文摘Grateloupia turuturu is a commercial red alga with potential value in nutraceuticals and pharmaceuticals. To supplement information on its life history and verify whether carpospores can be used for seedling culture, early development of G. turuturu was investigated under culture conditions (27°C, 10-13 mol/(m2.s) in irradiance, photoperiod 10:14 h L:D). Three physiological stages were recognized by continuous microscopic observation: division stage, discoid crust stage, and juvenile seedling stage. At the beginning of the division stage, the carpospores developed germ tubes into which the carpospore protoplasm was evacuated, and then the carpospore protoplasm in the germ tubes began to divide continuously until discoid crusts formed. Finally, upright thalli appeared on the discoid crusts and developed into juvenile seedlings. It took about 60 days for carpospores to develop into juvenile seedlings. The growth parameters, including germination rate for carpospores and discoid crust diameter, were recorded. These results contribute more information on the life cycle, and at the same time are of great significance in the scaling-up of artificial seedling cultures of G. turuturu.
基金Supported by the Shandong Agriculture Seedstocks Project and the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KSCX2-YW-N-47-02)the National High Techmology Research and Development Program of China (863 Program) (No.2006AA09Z421)and Experimental Marine Biology Lab, IOCAS
文摘Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedling nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study, we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures (10–28°C) and irradiances (10, 60 μmol photons m-2s-1) with a photoperiod of 12L:12D. The results indicate that both tetraspores and carpospores are tolerant to temperatures of 10–25°C, and have the highest relative growth rate at 20°C. Irradiance variances influenced the growth of the discoid crusts, and the influence was more significant with increasing temperature; 60 μmol photons m-2s-1 was more suitable than 10 μmol photons m-2s-1. The optimum temperature and irradiance for the development of seedlings was 20°C and 60 μmol photons m-2s-1, respectively.
基金Supported by the Shandong Agriculture Seedstocks Projectthe Knowledge Innovation Program of the Chinese Academy of Sciences(No.KSCX2-YW-N-247-02)
文摘Costaria costata(C.Agardh) Saunders is one of common kelps distributed in many coastal areas worldwide;however,in China,no reports have been made on cultivation of the genus.To investigate potential cultivation of the species in the northern part of China,trials on isolation and preservation of the gametophytes were conducted using C.costata from Korea;growth and development of the gametophytes were observed.We showed that at 10±1°C,60 μmol m-2s-1 and 12:12 h(L:D),freshly released zoospores settled down within 1 hour,and then developed into the primary cell during the following 2 days.After a vegetative growth phase lasting 6-8 days,female gametophytes became 3-4 times larger in diameter than that of the primary cell,but still remained at a unicellular stage,while male gametophytes divided into 4-10 cells with only a slight change in size.Fertilization occurred within 10 days after the zoospores were released from the sporangia,and the apical and basal tissues of the juvenile sporophyte divided and differentiated into the blade and stipe.Temperature and irradiance influenced gametophytic vegetative growth and developmental patterns.Generally,low irradiance(15 μmol m-2s-1 and 30 μmol m-2s-1) was unfavorable to the induction of fertility,but it enhanced female gametophyte division.The optimal conditions for vegetative growth were 15°C and 30 μmol m-2s-1.After transplantation of the juvenile seedlings and after eight months cultivation,the harvested mature blade reached 194 cm in length and 32.7 cm in width.Our study proves that it is feasible to implement propagation and large scale cultivation of C.costata in northern China.
