摘要: |
于1989–1992年在福建、江苏和青岛沿海采集红毛菜,进行野外观察,并在室内光照强度为70–100 μE/(m2s)的培养架上培养,每两周更换培养液,完成从原叶体到丝状体整个生活周期培养;对福建和江苏红毛菜有性生殖时两性细胞的构造和作用进行观察,并在生活周期的关键阶段用Wittmann方法压片,计数其染色体。结果表明,生长在福建的红毛菜染色体数目为n=6,2n=12;江苏和青岛的为n=8,说明中国的红毛菜至少有两种;细胞学观察证明,两性细胞已完成受精作用,果孢子是受精后的产物;同时,幼年红毛菜还能放散大量无性孢子,双极萌发成为与亲代相同的植物体,这可使红毛菜在短时期内数量剧增。 |
关键词: 繁殖方式 染色体数目 分类 红毛莱 |
DOI: |
分类号: |
基金项目:中国科学院基金资助项目,900655号 |
附件 |
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STUDIES ON REPRODUCTIVE MODES OF THE MACROSCOPIC PHASE AND CHROMOSOME OF BANGIA SP. FROM CHINA |
SUN Ai-shu,ZENG Cheng-kui (C K Tseng)
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Insititule of Oceanology, The Chinese Academy of deiences, Qingdao, 266071
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Abstract: |
Field and culture [15-30°C, 70-l00 μE/(m2*s)] studies on Bangia collected from coasts of Fujian Province, Jiangsu Province and Qingdao were conducted in l989-l992. An integral life cycle from macroscopic phase to microscopic phase had been completed in culture. The slides were prepared according to Wittinann (1965) in some key phases of the life cycle. The structure and function of the sexual cells, spermatic and carpogonia, in the sexual reproduction of Bangia sp. were observed with Olympus BH-2 microscope. The results were as follow. The carpogonia possessed extensive protrichogynes (Plate I: 2-6) and a few spermatia adhered on these projections (Plate 1:6) which disappeared after fertilization (Plate 1:7, 8). The cytological evidence indicates that the fertilization was, completed. Haploid chromosome number in the vegetative cells of macroscopic thallus and spermatia, and diploid chromosome number in carpospores had been shown by cytological studies of the different phases of life cycle. The carpospores were the products after fertilization. Simultaneously, some younger thalli of Bangia sp. could release a large number of asexual spores which developed in bipolar fashion to produce thalli which is the same as their parents. Therefore, the asexual reproduction mode could result in a significant increase in the plants within a limited period of time. The chromosomes of some key phases of the life cycle, vegetable cells, spermatia, carpogonia, neutral spores, were counted. The work proved that the chromosome number of Bangia sp. from Fujian was n = 6, 2n = 12 (Plate I:9, l0); and that from Jiangsu and Qingdao n = 8 (Plate I:11, 12). Morphylogical charateristics of Bangia sp. are very simple, whilst more difficulties have been encountered in the classi?cation of this genus. The studies on the chromosome number in this paper show that Bangia sp. from the different sites of China at least includes two species with different chromosome numbers. |
Key words: Reproductive modes, Chromosome number, Classification, Bangia sp. |