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Background The aim of this study was to determine the actual state of the photosynthetic apparatus and exhibit distinguishable differences in the chlorophyll fluorescence (ChlF) components in different seedling ages of M. oiwakensis plants subjected to different light intensity (LI). Potted 6-month-old greenhouse seedlings and field collected 2.4-year-old seedlings with 5 cm heights were selected and randomly separated into seven groups for photosynthesis measurements illuminated with 50, 100 (assigned as low LI), 300, 500, 1,000 (as moderate LI), 1,500 and 2,000 (as high LI) μmol m–2 s–1 photosynthetic photon flux density (PPFD) treatments. Results n 6-month-old seedlings, as LI increased from 50 to 2,000 PPFD, the values of non-photochemical quenching and photo-inhibitory quenching (qI) increased but potential quantum efficiency of PSII (Fv/Fm) and photochemical efficiency of photosystem II (ΦPSII) values decreased. High electron transport rate and percentage of actual PSII efficiency by Fv/Fm values were observed in 2.4-year-old seedlings at high LI conditions. Furthermore, higher ΦPSII was detected under low LI conditions, with lower energy-dependent quenching (qE) and qI values and photo-inhibition % decreased as well. However, qE and qI increased as ΦPSII decreased and photo-inhibition% increased under high LI treatments. Conclusions These results could be useful for predicting the changes in growth and distribution of Mahonia species grown in controlled environments and open fields with various combinations of varying light illuminations, and ecological monitoring of their restoration and habitat creation is important for provenance conservation and helps to formulate better conservation strategies for the seedlings.

Determining the correct conservation status of a species provides fundamental and critical information for species conservation policies. However, species traits and limited research efforts might decrease the accuracy of conservation assessments. Scleria sumatrensis has been considered a regionally extinct sedge plants in Taiwan, and the only, previous record of this species was from a collection provided by Urbain Faurie in 1914. More than one hundred years after Faurie’s record, we confirm the current occurrence of S. sumatrensis in Taiwan via morphological and molecular authentications in the present study. The morphological details of S. sumatrensis are provided based on the descriptions and illustrations. The conservation status for this species is reassigned to the Critically Endangered (CR) category. Further conservation efforts and research on S. sumatrensis are also discussed.

The pathophysiologic mechanisms underlying hypoxic-ischemic brain damage at any age are very complex and compared to adults, newborns respond differently to similar hypoxic-ischemic insult (Duffy et al., 1982; Raichle, 1983). These is general agreement that newborns are more resistant to hypoxia/ischemia and can survive hypoxia much longer than adults of the same species (Glass et al., 1944). The greater resistance of the immature animals has been attributed to its lower cerebral metabolic rate; a greater ability to maintain energy reserves through glycolysis; lesser complexity of the synaptic connections and/or differences in the enzyme content (Duffy et al., 1972; Duffy and Vannucci, 1977; Vannucci, 1989). On the other hand, evidence had been presented that exposure to moderate hypoxia during early postnatal life may result in disruption of functional activity at selected synapses even when it does not cause histologically measurable neuronal damage (Hedner and Lundborg, 1979; 1980). Similarly, it has been proposed that exposure of immature brain to moderate hypoxia may cause permanent changes in synaptic function and have significant impact on further neuronal development (Ihle et al., 1985; Lun et al., 1986).