The ozone layer acts as a natural filter in the atmosphere, which protects plant and animals from the increased UV irradiation from sunlight. Annually, scientists from around the world come to New Zealand to examine the impact of high UVB sunlight on plants and animals due to this natural hole in the ozone layer.
From comparative research, it has been shown that New Zealand has a 40 percent greater UVB light level than its geographically matched location (latitude, longitude and altitude) in the Northern hemisphere[i].
For those who enjoy the unique lifestyle offered in New Zealand, the higher UVB levels require summer time precautions such as protecting the skin with sunblock, and wide-brimmed hats. But what has been discovered is that plants also take precautions to avoid over-exposure to UV light.
Plants do this by producing secondary metabolites. These include bioactives such as flavonoids, phenolic compound, alkaloids, essential oils etc, as well as phytoestrogens, which are considered to be important compounds often exhibiting human health benefits. These groups of compounds can act as plant sunscreens and provide protection for the plants against UVB radiation[ii].