Seed Germination and Its Environment Adaptability of Endangered Tree Dracaena cambodiana

Abstract:

In order to reveal the endangered mechanisms of Dracaena cambodiana, the effects of pericarp, temperature, soil moisture and light intensity on seed germination of D. cambodiana were studied, and its environment adaptability was analyzed. The results showed that seed germination of D. cambodiana was significantly inhibited by pericarp, and could be significantly promoted by removing pericarp and watering pericarp soak solution. Seed germination was very sensitive to temperature with suitable temperature of 25℃, and seeds could not germinate under below 15℃ or above 30℃. Alternating-temperature had certain facilitation to seed germination. The germination of D. cambodiana seeds need high shading density, light intensity had significant effect on seed germination. The germination of D. cambodiana seeds was insensitive to soil moisture, there were not significant differences on GP (germination rate), CRG (coefficient of germination rate), GTL (germination time lag) and GI (germination index) among soil moistures ranged from 9.09% to 20.00%. Therefore, the germination of D. cambodiana seeds strongly depended on pericarp and microenvironment factors, i.e. temperature and light intensity. The microenvironment changes caused by habitat destruction might be one of main reasons for failure of sexual reproduction and endangerment of D. cambodiana.

Key words:Dracaena cambodiana;Environment adaptability;Seed germination;Endangered tree