| 摘要: |
| 为积累紫菜的新种质，本文对一种印度产紫菜—Pyropia radi的生活史进行了研究，结果发现：该紫菜的叶状体多为披针形，基部为楔形、呈褐绿色，梢部呈红紫褐色；藻体由单层细胞构成，极少含两层细胞；一个营养细胞中含1—2个星状色素体，多数只含一个；藻体的中部边缘具有稀疏的锯齿状突起，基部的齿状突起较密，一般的突起含有一至十多个细胞；成熟前的藻体厚度：基部为(51.54.23)μm，梢部为(29.42.31)μm，平均厚度41.2μm，成熟后的藻体逐渐加厚；成熟前的藻体长度5—10cm、宽度0.5—1cm，成熟后，藻体长度可达(458.7)cm、宽度为(51.21)cm；藻体的表观性别多数为雌雄异体，少数为雌雄同体，雌雄同体的个体其雌雄生殖细胞分别呈块状直线型分布于藻体；果孢子囊具有16或32个果孢子，分裂式为♀A2B2C4或♀A4B2C4，成熟的精子囊器具有64个精子囊，分裂式为♂A4B4C4；叶状体营养细胞和精子囊的核型为单倍，染色体数目为5个(n=5)，丝状体的营养细胞和膨大细胞的核型为双倍，染色体数目为10个(2n=10)。检测该紫菜的5.8S rDNA-ITS区序列发现，其5.8S保守区的160个碱基序列与坛紫菜相似度为100%。该紫菜的形态与结构、染色体数目、性别以及5.8S rDNA的保守序列等结果与坛紫菜极为相似，暗示它与坛紫菜的亲缘关系很近，但它们是否为同一个紫菜物种还有待深入研究。 |
| 关键词: 紫菜,生活史,丝状体,叶状体,染色体 |
| DOI：10.11693/hyhz20130400030 |
| 分类号: |
| 基金项目:国家高科技研究发展计划(863计划)资助项目，2012AA100811号；国家自然科学基金资助项目，31072208号；农业部公益性专项，200903030号；国家海洋局公益专项，201105008号，201105023号）；国家农业科技成果转化资金项目，2011GB2C000005号；上海市科委重点科技攻关项目，10391901100号 |
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| Biological characteristics and a part life-cycle of Pyropia radi (Bangiales, Rhodophyta) from India |
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zhang yan yan and yan xing hong
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College of Fisheries and Life science, Shanghai Ocean University, Shanghai 201306,College of Fisheries and Life science, Shanghai Ocean University, Shanghai 201306
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| Abstract: |
| In order to accumulate the germplasm resources of Pyropia, the biological characteristics and life history of Pyropia radi from India were studied in the present study. We found that the gametophytic blades of this species were membranous, lanceolate, showing wedge-shape and dark green in the base, but slightly reddish brown in the tip. The blades were most monostromatic, except for little part consisting of two layers of cells. There were one or two stellate chloroplasts in a vegetative cell of the blade, but most were only one there. The spines in the margins of the middle were sparse but rich in the base of the blades, consisting of one or more than ten cells in a spine, which became bigger and increased in the number as they aged. Before maturation, the base thickness of the blade was(51.5±4.23), the tip was (29.4±2.31) and the mean was 41.2μm, the blades were 5-10cm in the length and 0.5-1cm in the width, however, they could grow up to (45±8.7)cm in the length after matured. Most blades were dioecious but fewer were monoecious. The sectors of male and female sexual cells usually distributed linearly in the monoecious blades after matured. A mature carposporangium contained 16 or 32 carpospores, showing types of cell division as ♀A2B2C4 or ♀A4B2C4. A mature spermatangiophore contained 64 spermatangia, showing types of cell division as♂A4B4C4. The chromosome counts of vegetative cells and spermatangiain the blades were 5 (n=5), and the chromosome number in both vegetative cells and conchosporangial branch of conchocelis were 10 (2n=10).The 160 base sequence in 5.8S rDNA-ITS regions of this species was the same with that of Pyropia haitanensis.The above results indicated that the genetic relationship between this species and P. haitanensis is very close, however, it is need to study further to identify if they are the same species or not. |
| Key words: Pyropia, life-cycle, conchocelis, gametophytic blade, chromosome |
