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Growth and physiological acclimation to shade in young plants of Adesmia bijuga Phil., critically endangered species in central Chile

XV World Forestry Congress, 2-6 May 2022

Year of publication 2022

Place of publication Rome, Italy ;

Pages 6p.

Author Yáñez, M. A., Gómez P., Gajardo J., Espinoza S.

Publisher FAO ;

Product type Article

Synopsis (short abstract) Adesmia bijuga Phil. is an endemic and endangered shrub species of central Chile. Its potential shade intolerance is one of the leading hypotheses for its vigor loss when the species grows beneath closed canopies. In this study we aimed to assess growth and physiological acclimation to shade in young of A. bijuga plants. A nursery experiment was established with three light levels based on the interception of photosynthetic active radiation (PAR) (TRT0: control at full sun, TRT60: 60% shaded, and TRT90: 90% shaded), and maintained for 71 days during the summer season. Growth and leaf morpho-physiological responses were evaluated at the beginning, at the middle, and at the end of the experiment. The shading treatment increased plant height (H) and live crown percentage (Lcrown) compared to the control treatment at full sun. However, light-saturated photosynthetic rate (Amax), dark respiration rate (Rd), and light compensation point (Gi) were higher in TRT60 than in the other treatments.No differences were found among treatments for the apparent quantum yield (α). At this stage of plant development, our results suggest high acclimation plasticity of A. bijuga to light levels; however, a semi-shade environment (i.e., TRT60) favored a better performance of the species. Keywords: Shade tolerance, photosynthesis, light acclimation, forest restoration. ID: 3624055

Language English

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