| Title | Responses to UV-B radiation in Trifolium repens L. - Physiological links to plant productivity and water availability |
| Publication Type | Journal Article |
| Year of Publication | 2003 |
| Authors | Hofmann, R.W., Campbell B.D., Bloor S.J., Swinny E.E., Markham K.R., Ryan K.G., and Fountain D.W. |
| Journal | Plant, Cell and Environment |
| Volume | 26 |
| Issue | 4 |
| Pagination | 603 - 612 |
| Date Published | 2003 |
| ISSN | 01407791 (ISSN) |
| Keywords | drought, physiological response, Trifolium repens, ultraviolet b radiation, water availability |
| Abstract | This study used comparisons across nine populations of Trifolium repens (white clover) in conjunction with drought to examine physiological responses to ultraviolet-B radiation (UV-B). Plants were exposed for 12 weeks to supplementation with 13.3 kJ m-2 d-1 UV-B, accompanied by 4 weeks of drought under controlled environmental conditions. UV-B increased the levels of UV-B-absorbing compounds and of flavonol glycosides and this effect was synergistically enhanced by water stress. These changes were more pronounced for the ortho-dihydroxylated quercetin, rather than the monohydroxylated kaempferol glycosides. UV-B increased leaf water potential (ψL) by 16% under drought and proline levels by 23% under well-watered conditions. The intraspecific comparisons showed that higher UV-B-induced levels of UV-B-absorbing compounds, of quercetin glycosides and of ψL were linked to lower plant productivity and to higher UV-B tolerance under well-watered conditions. These findings suggest that: (1) slow-growing T. repens ecotypes adapted to other stresses have higher capacity for physiological acclimation to UV-B; and (2) that these attributes also contribute to decreased UV-B sensitivity under drought. |
| URL | http://www.scopus.com/inward/record.url?eid=2-s2.0-0037398506&partnerID=40&md5=f7aedd3c348cb55a8a61519c2f4a1405 |
| DOI | 10.1046/j.1365-3040.2003.00996.x |
