Plant pigment responses
A major focus in our research has been how some groups of pigments can assist plants to tolerate the effects of environmental stressors. The anthocyanins, in particular, appear to be highly versatile ‘stress-busters’. Described as ‘Nature’s Swiss Army Knife ’, these red pigments appear to protect leaves and stems from the effects of drought, high light, oxidative stress, temperature extremes, UV-radiation, salinity and heavy metals. They can also serve as an aposematic signal, warning approaching herbivores that the shoots are heavily defended with noxious chemicals.
More recently, our attention has turned towards another class of pigments, the betalains. Found only in one order of plants, the Caryophyllales, these red and yellow alkaloids have until recently received scant attention by the scientific community. Using the native New Zealand iceplant as a model system, our group has discovered that the pigments appear strongly associated with an ability to tolerate high levels of soil salinity. We recently obtained RSNZ Marsden funding to explore the possible mechanism by which betalains might confer salinity tolerance in these plants.