无柄小叶榕容器苗形态和生理质量评价指标筛选

The Screening of Morphologic and Physiological Indices for Quality Evaluation in Container Seedling of Ficus concinna var. subsessilis

因其独特的园林景观和耐低温、耐盐碱的特征,无柄小叶榕是热带、亚热带地区生态环境建设和泥质海岸防护林的重要树种之一。苗木质量直接影响到造林成活率及初期的长势。该研究以180天的无柄小叶榕容器苗为研究材料,测定无柄小叶榕容器苗的形态、生理等共31个指标因子,通过主成分分析、综合评定,找出能够反映无柄小叶榕容器苗质量的关键指标以及辅助指标。研究结果表明:无柄小叶榕容器苗的苗木质量主要决定于苗木的总生物量、地下干物质、地径和根团。评定无柄小叶榕容器苗的质量应以苗木的地径、全株干(鲜)重、质量指数、根干(鲜)重、茎干(鲜)重等形态指标,结合光合指标(净光合速率、胞间CO2浓度、蒸腾速率、水分利用率)、叶绿素含量(A、B及总叶绿素)、根系活力等生理指标为关键指标,并辅以苗高和高径比作为辅助指标来综合评价。

Ficus concinna var. subsessilis is one of the important afforestation species in ecological environment construction and the shelter forest of silting coastal area in tropical and subtropical areas, because of its characteristic of unique landscape and the tolerance to low temperature and saline-alkali. The quality of container seedling affects the survival rate and early growth of reforestation directly. In this study, F. concinna var. subsessilis container seedlings of 180 days for research materials, 31 morphological and physiological indexes were measured. By means of principal component analysis and comprehensive evaluation, the key indexes and auxiliary indexes were selected, which can reflect on the quality of F. concinna var. subsessilis container seedling. The study showed that the quality of F. concinna var. subsessilis container seedling mainly decided on the total biomass, the underground biomass, the ground diameter and the root tissue. The quality of F. concinna var. subsessilis container seedling can be evaluated using key indexes and 2 auxiliary indexes by means of comprehensive evaluation. The 8 key indexes 5 morphological indexes and 3 physiological indexes, the former included ground diameter, total dry （fresh） weight, quality index, root dry （fresh） weight, stem dry（fresh） weight, and the latter included photosynthesis indexes （Pn, Ci, Tr, water use efficiency）, chlorophyll content （chlorophyll a, chlorophyll b and chlorophyll a＋b） and root activity. The 2 auxiliary indexes were height of seedling and the ratio of height to ground diameter.