Abstract: [Objective] To reveal seed germination characteristics of the rare and endangered plant Garcinia paucinervis and its suitable conditions of seedling growth, the endangered factors of G. paucinervis were analyzed during seed germination, which provided theoretical support for its protection, introduction, domestication and efficient seedling propagation.[Method] The germination conditions of G. paucinervis seeds were discussed in terms of the ecological factors that may affect their germination (e.g. temperature, light, soil moisture, substrate, burial depth and different populations) and the biological characteristics (e.g. seed coat and seed weight). The germination conditions of G. paucinervis seeds were discussed and the endangered mechanism was predicted.[Result] The germination processes of G. paucinervis seeds were slow and irregular. Both endocarp and seed coats delayed seed germination, nevertheless, they had no effect on final germination percentage (GP). The seed coat had no inhibitory effect on germination. The seeds could germinate at 25℃, 32℃, and room temperature, and the germination process and growth rate could be obviously accelerated at 32℃, but the seeds did not germinate at 18℃ and 37℃. The seeds were able to germinate under the condition of continuous light, continuous darkness and periodic light. The germination speed was the fastest and the germination was the most uniform under the periodic light, but there was no significant difference in GP under 3 light conditions. Thus, the G. paucinervis seed was the non-hotoblastic seed. The GP was the highest when seeds were sown in the sand and peat soil. The seeds germinated more slowly in clayey loam or limestone soil, where their GP was lower. The aboveground and underground parts of seedlings in peat soil and vermiculite grew better. The limestone soil with 40%~60% moisture content was more suitable for germination, and Germination time lag (GTL) was longer under 80% moisture content, but the seed could not germinate under 20% moisture content. In the same burial depth, compared with limestone soil as substrate, the germination energy (GE) and the germination percentage (GP) of seeds sowed in sand was higher. With the increase of burial depth, both GE and GP decreased, and the germination speed was the fastest and the germination was the most uniform with the treatment of sand as substrate and 0.5 cm burial depth. Among the seeds of Nonggang (NG), Anning (AN) and Hurun (HR) populations, the GP of HR population was the lowest and the germination speed of HR population was the slowest. The seedlings of NG population were slender, and the seedlings of HR population were stouter and shorter, and whose root system was more developed. There were no significant differences in most of germination parameters and seedling growth among 3 weight level seeds (<4 g,4~5 g and >5 g), so seed weight had no significant effect on seed germination and seedling growth. The seeds germinated had been removed shoot and radicle then sowed again, which could still germinate, so G. paucinervis seeds had the ability of regeneration.[Conclusion] The G. paucinervis seeds have dormancy. The temperature range of its seed germination is narrow and the seed germination is sensitive to substrate ventilation and water permeability. The regeneration capacity of seeds can prevent seed's failure to seedling and strengthen their viability. However, the slow germination speed and growth of seedlings are not conducive to the rapid occupation of population space resources, and seed germination has a higher requirement for soil permeability and moisture, which may be important reasons for the decline of their populations and their endangerment.

Key words: seed germination, seedling growth, ecological adaptability, endangered causes, seed regeneration