Chin J Plant Ecol ›› 2011, Vol. 35 ›› Issue (7): 751-758.DOI: 10.3724/SP.J.1258.2011.00751

Special Issue: 青藏高原植物生态学:生理生态学

Previous Articles     Next Articles

Effect of accumulated temperature on seed germination—a case study of 12 Compositae species on the eastern Qinghai-Tibet Plateau of China

LIU Wen, LIU Kun, ZHANG Chun-Hui, DU Guo-Zhen*()   

  1. Key Laboratory of Arid and Grassland Ecology of Ministry of Education, Lanzhou University, Lanzhou 730000, China
  • Published:2011-08-18
  • Contact: DU Guo-Zhen


Aim Temperature is an important environmental factor influencing seed germination. Our objective was to research the seed germination response of 12 Compositae species from the eastern Qinghai-Tibet Plateau of China to different temperatures using the accumulated temperature model.
Methods All 12 species belong to four genera of Compositae. Seeds of each species were germinated at five constant temperatures (5, 10, 15, 20 and 25 °C), and germination was recorded once per day. We combined the logistic function and the accumulated temperature equation and used non-linear regression to estimate the base temperature and accumulated temperature for seed germination of each species.
Important findings The average base temperature and accumulated temperature of the 12 species were 0 °C and 94.5 °C·d, respectively. The base temperature was lower and the accumulated temperature was higher than reported by previous researchers. These are the result of long-term adaptation to the temperature environment of the Qinghai-Tibet Plateau. There was a significant negative correlation between base temperature and accumulated temperature (p = 0.04). Therefore, species with lower base temperature would avoid the risk of seeds germinating earlier in an environment with changeable temperature. A significant positive correlation existed between seed mass and accumulated temperature (p = 0.01). Under relatively constant base temperature, small-seeded species germinated faster than large-seeded ones, giving them priority of germination in early succession.


Key words: accumulated temperature, base temperature, Compositae, seed germination, seed mass, Qinghai- Tibet Plateau