Light‐Induced Adaptive Responses under Greenhouse and Controlled Conditions in the Fern Pteris cretica var. ouvrardii

Abstract

The photosynthetic capabilities of the fern Pteris cretica var. ouvrardii were analysed by means of the light response curves of CO2 exchange. In control growth conditions (greenhouse, low‐light: 20–32 W m−2); photosynthesis was shown to be saturated for low irradiance (20–25 W m−2); the saturating photosynthetic rate, very low as compared to higher plants, was due to an extremely high intracellular resistance. When irradiance during the photosynthesis measurement was higher than 60–80 W m−2, a constant decline of net CO2 exchange as a function of time was observed. When irradiance during growth was enhanced, whether in greenhouse (20–250 W m−2) or controlled (62 W m−2) conditions, the first fronds that had developed in the new condition from the crosier stage exhibited decreased net maximal photosynthesis and a decreased efficiency in low light, but saturating irradiance was unmodified. However, the fronds whose entire differentiation (from meristem) occurred under these moderate irradiances (plants defoliated of all fronds and crosiers at the time of transfer), possessed more efficient photosynthetic characteristics than control plants. Pteris is able to grow under extreme shade conditions (4–8 W m−2); light saturating photosynthesis and efficiency are higher under extreme shade than under control conditions. These adaptive characteristics indicate that Pteris is a well‐adapted shade species.

Light‐Induced Adaptive Responses under Greenhouse and Controlled Conditions in the Fern Pteris cretica var. ouvrardii

“…This paper compares leaf growth, morphology, anatomy and chloroplast ultrastructure in plants grown under a series of irradiances in the greenhouse and under controlled artificial conditions. A parallel study, reported in the accompanying paper (Hariri and Prioul 1977), describes the photosynthetic characteristics of P. cretica var. ouvrardii under the same irradiance regimes.…”

Photosynthesis limitations in three fern species

“…Hence, understanding their photosynthetic characteristics would be crucial to unravel the evolution of photosynthetic traits in land plants. In general, ferns have been reported to have a much lower range of photosynthetic capacities than seed plants (Hariri and Prioul , Durand and Goldstein , Wright et al , Brodribb et al ). In a global comparison by the Glopnet group (Wright et al , ), a limited number of fern species were considered, and they presented significantly lower photosynthetic capacities than any functional group within seed plants for similar ranges of leaf mass per area and nitrogen contents, i.e.…”

“…lower intrinsic water use efficiency—has also been reported for ferns, as compared to seed plants (Gratani et al , Volkova et al , McAdam and Brodribb ). While, in part, these differences could be caused by the fact that many ferns present shade‐specific traits (Hariri and Prioul , Johnson et al ), this cannot be generalized and, even focusing on sun ferns only, their photosynthetic capacity and resource use efficiency are lower than in seed plant (Volkova et al , , Haworth et al ). The underlying causes of these photosynthetic differences between ferns and seed plants are still unknown due to lack of specific studies focused in this topic.…”

Impact of one year crozier removal on long-term frond production in Matteuccia struthiopteris

“…A previous study by Marrs et al (1993) on Pteridium aquilinum yielded similar results following one or two annual defoliations. Hariri and Prioul (1978) showed that defoliated Pteris cretica produced a second set of fronds with higher photosynthetic capacity. While we did not measure M. struthiopteris photosynthetic capacity directly, any increase that may have occurred did not fully compensate for leaf area lost, since there were lower starch reserves at the end of the season in the defoliated plants.…”