The non-gibberellic acid-responsive semi-dwarfing gene uzu affects Fusarium crown rot resistance in barley
1 CSIRO Plant Industry, 306 Carmody Road, St Lucia QLD 4067, Australia
2 Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu 611130, China
3 Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Wenjiang, Chengdu 611130, China
4 Institute of Food Crops, Jiangsu Academy of Agricultural Science, 50 Zhongling Street, Nanjing 210014, China
5 Tasmanian Institute of Agriculture and School of Agricultural Science, University of Tasmania, P.O. Box 46, Kings Meadows, Tasmania 7250, Australia
6 School of Plant Biology, The University of Western Australia, Perth, WA 6009, Australia
BMC Plant Biology 2014, 14:22 doi:10.1186/1471-2229-14-22Published: 13 January 2014
Studies in Arabidopsis show that DELLA genes may differentially affect responses to biotrophic and necrophic pathogens. A recent report based on the study of DELLA-producing reduced height (Rht) genes in wheat and barley also hypothesized that DELLA genes likely increased susceptibility to necrotrophs but increased resistance to biotrophs.
Effects of uzu, a non-GA (gibberellic acid)-responsive semi-dwarfing gene, on Fusarium crown rot (FCR) resistance in barley were investigated. Fifteen pairs of near isogenic lines for this gene were generated and assessed under two different temperature regimes. Similar to its impacts on plant height, the semi-dwarfing gene uzu also showed larger effects on FCR severity in the high temperature regime when compared with that in the low temperature regime.
Results from this study add to the growing evidence showing that the effects of plant height on Fusarium resistances are unlikely related to DELLA genes but due to direct or indirect effects of height difference per se. The interaction between these two characteristics highlights the importance of understanding relationships between resistance and other traits of agronomic importance as the value of a resistance gene could be compromised if it dramatically affects plant development and morphology.