UV radiation as a modulator of plant defense and biogeochemical cycles. Keynote Lecture, Bled, Slovenia (Mar 2014).

BALLARE CL

Bled

Conferencia; I COST-Action FA0906 Final Network Meeting.; 2014

Carlos L. Ballaré Senior Research Scientist (Consejo Nacional de Investigaciones Científicas y Técnicas, CONICEY), and Professor (Univ. Nacional de San Martín and University of Buenos Aires) Lab website: http://epl.agro.uba.ar Member, Environmental Effects Assessment Panel, United Nations Envrionment Programme (UNEP) http://ozone.unep.org/Assessment_Panels/EEAP/index.shtml Editor-in-Chief, Oecologia (Springer) http://www.springer.com/life+sciences/ecology/journal/442 UV radiation as a modulator of plant defense and biogeochemical cycles. Ballaré C. L. 1IFEVA, Consejo Nacional de Investigaciones Científicas y Técnicas?Universidad de Buenos Aires, C1417DSE Buenos Aires, Argentina and IIB-INTECH, Consejo Nacional de Investigaciones Científicas y Técnicas?Universidad Nacional de San Martín, B1650HMP Buenos Aires, Argentina UV radiation is a minor fraction of the daylight spectrum. Research efforts over the past three decades have thoroughly characterized the effects of the UV-B (280-315 nm) component. In this talk, I will address the following points. A) Whereas UV-B has modest effects on the growth of terrestrial plants, it is a strong positive modulator of plant immunity. The mechanisms that mediate this effect of UV-B are becoming increasingly well understood (1). Agricultural intensification, which involves increased planting density and canopy leaf area indexes, may lead to reduced plant exposure to the beneficial effects of UV-B radiation, resulting in reduced plant defenses against pest and diseases (2). B) Changes in UV resulting from changes in climate or land use may have more important consequences on terrestrial ecosystems than those derived from ozone depletion. This is because the resulting variations in UV may affect a greater range of ecosystems, and will not be restricted solely to the UV-B component. Several processes that are not very sensitive to UV-B can be strongly affected by UV-A radiation (315-400 nm). One example is the physical degradation of plant litter (photodegradation), which has important direct and indirect effects on carbon sequestration in terrestrial ecosystems (3). References 1. Ballaré CL. 2014. Light regulation of plant defense. Annual Review of Plant Biology 65: doi: 10.1146/annurev-arplant-050213-40145 2. Ballaré CL, Mazza CA, Austin AT, Pierik R. 2012. Canopy light and plant health. Plant Physiology 160: 145-55 3. Austin AT, Ballaré CL. 2010. Dual role of lignin in plant litter decomposition in terrestrial ecosystems. Proceedings of the National Academy of Sciences of the United States of America 107: 4618-22 Acknowledgement Supported by CONICET, ANPCYT, UBACYT (Argentina)