中文摘要：

从已获得的4种坛紫菜优质高产品系中，筛选出抗高温的优良品系YZ-3。在28℃和29℃下培养15d后，YZ-3品系的壳孢子成活率分别达73．2％和52．6％，分裂率分别为100％和82．8％；而对照组野生型（WT）品系的壳孢子成活率分别只有10．3％和4．6％，分裂率分别为89．7％和65．9％；YZ-3品系的壳孢子成活率和分裂率均远高于WT品系。把在常温（24℃）下培养35d的壳孢子苗，再分别培养在24、28和29℃作抗高温试验，培养25d后发现，YZ-3品系的幼苗平均体长分别增加了33．6、23和15倍，而WT品系的苗平均体长分别只增加了7．7、1．4和0．9倍；YZ-3品系的苗平均体长分别是WT品系的3．8、8．8和7．4倍。在28℃和29℃组，WT品系幼苗培养15d就大面积腐烂；而YZ-3品系幼苗培养25d也不腐烂。上述结果表明YZ-3品系是抗高温的。

英文摘要：

In this paper, it was verified that the improved strain （ YZ-3 ） of Porphyra haitanensis Chang et Zheng obtained previously in the lab is a high-temperature resistant strain. When the conchospores of the YZ-3 strains and the wild-type strain （WT） were cultured at 28 ℃ and 29 ℃, the survival rate of conchospores was 73.2% and 52.6% for YZ-3 strain, but 10.3 and 4.6% for WT strain, respectively. The division rate of conchospores at 28 ℃ and 29 ℃ was 100 and 82.8% for YZ-3 strain, and 89.7% and 65.9% for WT strain, respectively. Both survival and division rates of conchospores of YZ-3 strain were significantly higher than those of WT strain either in culture at 28 ℃ and 29 ℃. When the conchospore germlings of YZ-3 and WT strains which have been cultured at 24 ℃ for 35 days were cultured at 24 ℃, 28 ℃ and 29 ℃ for 25 days, the mean length of blades increased 33.6, 23 and 15 times for YZ-3 strain, and only 7.7, 1.4 and 0.9 times for WT strain compared with the original mean length, respectively. When the blades cultured at 24 ℃, 28 ℃ and 29 ℃, the mean length of the blades of YZ-3 strain was 3.8, 8.8 and 7.4 times as WT strain, respectively. When the blades were cultured at 28 ℃ and 29 ℃, the blades of WT strain began to decay after cultured for 15 days, however, the blades of YZ-3 strain did not decay even being cultured for 25 days. These results indicated that YZ-3 strain is strongly resistant to high temperature （28 ℃ and 29 ℃ ）.