本研究旨在为深入构建龙须菜(Gracilaria/Gracilariopsis lemaneiformis)育种体系提供基础数据。采用DTOPSIS 综合评价法对实验室构建的龙须菜 GL 家系的 F1配子体的性状进行分析与评价,以期把 F1配子体的综合性状这一模糊量化指标转化为该株系对理想解的相对接近度 Ci值的量化指标,进而对各藻株的综合性状优劣进行综合分析,为未来良种的杂交以及选育提供依据。所测的100株藻体中,线性生长速率变化范围为2.0~7.3%/d,变异系数为26.79%,标准差达到1.28,各藻株之间存在明显的差异。藻株的分枝数分布很不集中,变异极为显著,其平均数为1.93个,标准差为0.8,变异系数为41.17%,差异明显,变异幅度相对很大。主枝基部直径变化范围1.4~2.2 mm,标准差达到0.18,变异系数在3个性状中最小,为9.87%。线性生长速率、分枝数、基部直径等性状分布均呈现明显的正态分布特征,标准差分析显示,各性状相对本身参数变化幅度较大,说明 F1配子体存在一定的性状变异,可以挑选性状差异大的藻种进行杂交以期获得优良藻种。DTOPSIS 综合评价分析显示20、47、93、6、31株系综合性状的评价值比较高,为后期人工选育优良藻种提供依据。%Gracilaria/Gracilariopsis lemaneiformis is the second largest cultivated alga in China, with economic value related to agar production and bioremediation potential by eliminating eutrophication. It is important to establish a ge-netic breeding system for Gracilaria/Gracilariopsis lemaneiformis (GL) to promote sustainable development of the mariculture industry. In the present study, 3 productive characters of the F1 generation of GL gametophytes, including linear growth rate, branch number, and central base diameter, were analyzed and evaluated using the DTOPSIS com-prehensive evaluation method to convert qualitative comprehensive traits of F1 gametophytes to quantitative indicators of Ci value, which is necessary to determine an ideal solution to improve breeding. Thus, characters of all strains were comprehensively analyzed and provided evidence for future cultivar hybridization and selection. Among the 100 individuals tested, the linear growth rate ranged from 2.0%/d to 7.3%/d, with an average of 4.76%/d (standard deviation, 1.28). Its variable coefficient was 26.79%, and that the difference among individuals was significant. Branch number was unevenly distributed with extremely substantial variation. The mean value was 1.93 with a range from 1 to 5, standard deviation of 0.8, and variable coefficient of 41.17%;this was the most substantial variation and a relatively large variation range. The average central base diameter was 1.8 mm, with a range from 1.4 mm to 2.2 mm, and standard deviation of 0.18. Its variable coefficient, 9.87%, had the lowest variation range and least vari-ance difference among the three productive characters. All of the above three characters had normal distributions:Most of the linear growth rates of F1 gametophytes distributed between 3.0%/d and 6.0%/d; 40% of individuals had 2 branches after 28 days of culturing;and central base diameter mostly distributed between 1.6 mm and 2.1 mm. Standard deviation analysis revealed large variation in the range of characters of the F1 generation of these gametophyte plants. Based on DTOPSIS comprehensive analysis, three productive characters of F1 generation gametophytes were compre-hensively evaluated, and 100 strains were ranked based on their Ci value. The results showed that strains 20, 47, 93, 6, and 31 were superior to the others because they had higher Ci values, which indicates that they have a balance of ad-vantageous growth rate, branch number, and central base diameter. These strains could be exploited for genetics-based breeding before they reach maturity. In addition, adjacent strains ranked by DTOPSIS analysis had similar Ci values, whereas strains at either extreme showed substantial difference, which was consistent with the normal distribution. The large variation among F1 GL gametophytes of the three productive characters indicates that strains with sub-stantial character differences can be chosen as parents for hybridization to obtain improved varieties. DTOPSIS analysis intuitively measured comprehensive traits of F1 gametophytes, which provides a theoretical basis for subsequent re-search on strain selection and further construction of a Gracilaria/Gracilariopsis lemaneiformis genetic breeding system.
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