Biomass and Morphology Responses of Fritillaria unibracteata to Shading and Warming

Fritillaria unibracteata Hsiao and Hsia (Liliaceae) (F. unibracteata) is a perennial and protected species distributed in the meadow or under the shrub at the eastern Tibetan Plateau. To understand how F. unibracteata response to changing environment, OTC (open top chamber) and PSN (Polypropylene shading nets) were used to simulate warming and shading effects. Two years later, dry biomass of each organ (leaf, stem, bulb and root), leaf length (LL), leaf area (LA) and special leaf area (SLA) were measured individually to determine F. unibracteata responses to environmental change. The results showed that: (1) total biomass (TB), leaf biomass (LB) and root biomass (RB) increased significantly under warming treatment (P<0.05), but no significant change under shading; (2) LB/RB was decreased under warming, while both LB/RB and AB/BeB showed no significant responses to shading; (3) leaf morphological characteristics responded significantly to warming and shading; leaf length (LL) significantly increased under both shading and warming treatments (P<0.05); leaf area (LA) increased significantly under warming treatment; special leaf area (SLA) increased significantly under shading treatment. Based on the results above, we get conclusions as below: (1) F. unibracteata responded to warming and shading effects differently; (2) For perennial alpine plants such as F. unibracteata, morphological traits may be more sensitive to environment variations than other traits.