UV-A protection in mosses growing in continental Antarctica

Historical ozone concentrations and flavonoid levels in herbarium specimens of the Antarctic moss Bryum argenteum

“…We therefore considered that our assumption of a uniform ozone distribution over Antarctica was not a major source of error in this analysis. A 2‐week period was chosen because the biological half lives of flavonoids in this species are between 3 and 15 days (Markham et al , 1990; Green et al , 2005). A similar period (10 days) was used in the analysis of moss UV‐absorbing compounds by Dunn & Robinson (2006).…”

“…In continental Antarctica, much confusion has surrounded the taxonomy of the dominant moss genus Bryum . Sometimes referred to as Bryum subrotundifolium (Seppelt & Green, 1998; Green et al , 2005), recent analysis has confirmed this moss as B. argenteum (Bednarek‐Ochyra & Smith, 2008). Two forms of this moss were reported by Green et al (2005): B. argenteum var.…”

Photoprotective pigments in red and green gametophytes of two New Zealand liverworts

“…in certain bryophytes, too, red pigmentation has been postulated to exert beneficial effects. Red forms of the Antarctic moss Ceratodon purpureus were found to be more resistant than green forms to the effects of elevated Uv-Aradiation (Green et al 2005), and the red cell walls in leaves of the Antarctic liverwort Cephaloziella varians were postulated to confer protection from strong light and/or Uv radiation (Post & vesk 1992;Newsham et al 2005). Such protection may be critical for bryophytes that grow in exposed environments and are potentially at risk of photodamage from intense sunflecks and elevated UV levels.…”

“…in addition to the elevated light levels, however, sun-exposed habitats also subject liverworts to the possibility of drought, temperature stress, high Uv-radiation levels, and oxidative damage; any one or a combination of these could be involved in red pigmentation. Uv-radiation, for example, has been shown to cause the formation of red pigments in a variety of mosses and liverworts (Green et al 2005;Newsham et al 2005), and both drought and frost induce red pigmentation in Sphagnum moss (Rudolph 1964). Processes leading to the induction of red pigments in New Zealand's liverworts warrant further investigation.…”

Dynamic response of UV-absorbing compounds, quantum yield and the xanthophyll cycle to diel changes in UV-B and photosynthetic radiations in an aquatic liverwort

“…The responses of bryophytes to UV-B show long-term seasonal changes Lappalainen et al, 2010), as well as short-term day-to-day variations (Newsham et al, 2002(Newsham et al, , 2005Newsham, 2003) and diel changes (Green et al, 2000;Conde-Álvarez et al, 2002;Lud et al, 2002Lud et al, , 2003Green et al, 2005;Lappalainen et al, 2010). All these studies were conducted under field conditions, where the interference of water availability and temperature can mask the responses to UV (Lappalainen et al, 2010).…”