a strategy for the proliferation of ulva prolifera, main causative species of green tides, with formation of sporangia by fragmentation石莼的扩散的策略prolifera,主要病因种类的绿色浪潮,形成孢子囊的碎片.pdfVIP

A Strategy for the Proliferation of Ulva prolifera, Main Causative Species of Green Tides, with Formation of Sporangia by Fragmentation 1 1 1 1,2 1 2,3 Shan Gao , Xiaoyuan Chen , Qianqian Yi , Guangce Wang *, Guanghua Pan , Apeng Lin , Guang Peng2 1 College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, China, 2 Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China, 3 Graduate School, Chinese Academy of Sciences, Beijing, China Abstract Ulva prolifera, a common green seaweed, is one of the causative species of green tides that occurred frequently along the shores of Qingdao in 2008 and had detrimental effects on the preparations for the 2008 Beijing Olympic Games sailing competition, since more than 30 percent of the area of the games was invaded. In view of the rapid accumulation of the vast biomass of floating U. prolifera in green tides, we investigated the formation of sporangia in disks of different diameters excised from U. prolifera, changes of the photosynthetic properties of cells during sporangia formation, and development of spores. The results suggested that disks less than 1.00 mm in diameter were optimal for the formation of sporangia, but there was a small amount of spore release in these. The highest percentage of area of spore release occurred in disks that were 2.50 mm in diameter. In contrast, sporangia were formed only at the cut edges of larger disks (3.00 mm, 3.50 mm, and 4.00 mm in diameter). Additionally, the majority of spores liberated from the disks appeared vigorous and developed successfully into new individuals. These results implied that fragments of the appropriate