Effects of UV-B radiation

UV-B radiation affects agriculture in complex interactions with climate change. Increasing UV-B radiation is known to harm crops, causing damage in 2/3 of over 680 plant cultivars tested. UV-B radiation can harm crops directly, through heritable mutations in DNA, changes to membranes, protein denaturation, and indirectly through changes to several physiological and growth processes. UV-B radiation affects species and even plant cultivars differently, and little is known how changing UV-B radiation affects crops, in order to develop algorithms for models for crops. Also not well understood is how UV-B radiation affect crops in combination with other environmental stressors. UV-B radiation can affect crops in complex ways, harming well-watered plants more than plants under drought for some crop species, while harming plants fertilized in excess more than those adequately fertilized, but these effects have been studied only in a few species. UV-B radiation as well as visible light accelerate litter decomposition in a process called photodegradation, possibly stimulating more nutrients to be released from the litter and then taken up by plants to produce more biomass or improve nutrition in rangelands of the western U.S. that receive high doses of solar radiation.

UVMRP studies both isolated and combined effects of UV-B radiation with environmental stressors. The studies are on crops, trees and rangeland, and consider the effects of UV-B radiation alone and combined with other environmental stressors such as moisture (drought), temperature, ozone, soil nutrients and CO2. The results of the studies will be incorporated into models of crops, trees and rangelands.

These studies are continuing at Mississippi State University (MSU) and Colorado State University. Primary studies use plant growth chambers known as the Soil-Plant-Atmosphere-Research (SPAR) facility at MSU, which is capable of controlling the aerial environment over a wide range of set points (atmospheric CO2 concentration, humidity, and UV-B radiation). The primary studies are complemented by other lab and field experiments, satellite observations, and modeling.

SPAR Facility

For more detail about current and past research, select an interest below.