Photosynthetic studies on eight filmy ferns (hymenophyllaceae) from shaded habitats in Malaysia / Nurul Hafiza Binti Mohammad Rosli

• Main Author: Mohammad Rosli, Nurul Hafiza
• Format: Thesis
• Published: 2014
• Subjects: Q Science (General)
• Online Access: http://studentsrepo.um.edu.my/4776/1/SGR100064_Nurul_Hafiza.pdf; http://studentsrepo.um.edu.my/4776/

The photosynthetic characteristics of eight Malaysian Hymenophyllaceae filmy ferns from shady habitats were investigated in this study. Chlorophyll content was highest in Trichomanes meifolium, followed by Cephalomanes obscurum, Hymenophyllum serrulatum, H. denticulatum, H. javanicum, H. acanthoides, H. exsertum and H. blandum with values ranging from 3.3 to 8.6 mg g-1 fresh weight, compared to two sun ferns, Dicranopteris linearis and Nephrolepis biserrata. Soluble protein content was remarkably high in H. serrulatum, followed by Dicranopteris linearis and Nephrolepis biserrata. Protein to chlorophyll ratio in the filmy ferns was low compared to the sun ferns. Chloroplast number and size ranged between 34 to 138 per cell profile and between 4.8μm to 6.5μm in diameter, in the Hymenophyllaceae. Rubisco RbcL profiling showed clear differences between the filmy ferns and the sun species. Quantum efficiency measurements in four Hymenophyllaceae spp exhibited Fv/Fm values ranging between 0.73 to 0.81. The Hymenophyllaceae species also showed low in vivo CO2 assimilatory rates and light saturation points, ranging between 5 to 17 μmol CO2 m-2 s-1 and between 100 to 150 μmol m-2 s-1 respectively, except for H. blandum which saturated at around 300-400 μmole m-2s- 1. In contrast, the sun ferns Dicranopteris linearis and Nephrolepis biserrata, showed higher CO2 saturation rates, 22 μmol CO2 m-2 s-1 and 30 μmol CO2 m-2 s-1, respectively, and higher light saturation point at around ~600μmole m-2s-1.The findings add further to our understanding on how the filmy ferns adapt and thrive in their humid and shady habitats.