J Plant Ecol ›› 2015, Vol. 8 ›› Issue (2): 159-165 .DOI: 10.1093/jpe/rtv014

• Research Articles • Previous Articles     Next Articles

Woolly and overlapping leaves dampen temperature fluctuations in reproductive organ of an alpine Himalayan forb

De-Li Peng1,2,3, Yang Niu1, Bo Song1, Jian-Guo Chen1, Zhi-Min Li4, Yang Yang1 and Hang Sun1,*   

  1. 1 Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; 2 Institute of Ecology and Geobotany, Yunnan University, Kunming 650091, China; 3 University of Chinese Academy of Sciences, Beijing, 100049, China; 4 School of Life Sciences, Yunnan Normal University, Kunming 650500, Yunnan, China
  • Received:2015-01-14 Accepted:2015-01-24 Published:2015-03-27
  • Contact: Sun, Hang

Woolly and overlapping leaves dampen temperature fluctuations in reproductive organ of an alpine Himalayan forb

Abstract: Aims Studying the ecological significance of highly specialized morphological traits evolved by alpine plants could help us to understand the adaptation and evolution of these plants under severe alpine environment. We explored the adaptive significance of woolly and overlapping leaves for reproduction in Eriophyton wallichii, a perennial herb native to the subnival belt of the Himalaya-Hengduan Mountains.
Methods We examined whether the trichomes could influence the leaf wettability, temperature and leaf reflectance spectra in the lab. And we investigated the thermal benefits of the woolly and overlapping leaves for flowers and fruits in the field. Pollen viability and seed germination were also examined in the lab to assess whether these leaves enhance reproductive fitness.
Important findings Our results showed that dense trichomes impart good water repellency, absorption of solar radiation and accumulation of leaf heat. The woolly and overlapping leaves increased the interior temperature of flowers and fruits to an optimal level on sunny hours, but prevented them from overheating when transient intense solar radiation occurs. This kept optimal temperatures in plants' reproductive organs, thus promoting the development of pollen and seed in alpine environment.

Key words: buffer effect, Eriophyton wallichii, overheating, subnival belt, trichomes, water repellency

摘要:
Aims Studying the ecological significance of highly specialized morphological traits evolved by alpine plants could help us to understand the adaptation and evolution of these plants under severe alpine environment. We explored the adaptive significance of woolly and overlapping leaves for reproduction in Eriophyton wallichii, a perennial herb native to the subnival belt of the Himalaya-Hengduan Mountains.
Methods We examined whether the trichomes could influence the leaf wettability, temperature and leaf reflectance spectra in the lab. And we investigated the thermal benefits of the woolly and overlapping leaves for flowers and fruits in the field. Pollen viability and seed germination were also examined in the lab to assess whether these leaves enhance reproductive fitness.
Important findings Our results showed that dense trichomes impart good water repellency, absorption of solar radiation and accumulation of leaf heat. The woolly and overlapping leaves increased the interior temperature of flowers and fruits to an optimal level on sunny hours, but prevented them from overheating when transient intense solar radiation occurs. This kept optimal temperatures in plants' reproductive organs, thus promoting the development of pollen and seed in alpine environment.