Effects of plant height on type I and type II resistance to fusarium head blight in wheat |
| |
Authors: | W. Yan H. B. Li S. B. Cai H. X. Ma G. J. Rebetzke C. J. Liu |
| |
Affiliation: | 1. CSIRO Plant Industry, Queensland Bioscience Precinct, 306 Carmody Road, St Lucia, QLD 4067, Australia;2. Institute of Food Crops, Jiangsu Academy of Agricultural Science, 50 Zhongling Street, Nanjing 210014;3. Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, 50 Zhongling Street, Nanjing 210014, China;4. CSIRO Plant Industry, PO Box 1600, Canberra ACT 2601;5. School of Plant Biology, University of Western Australia, Perth, WA 6009, Australia |
| |
Abstract: | By carefully separating type I and type II resistances, the possible effects of plant height on fusarium head blight (FHB) resistance in wheat were assessed using near‐isogenic lines (NILs) for several different reduced‐height (Rht) genes. Tall isolines all gave better type I resistance than their respective dwarf counterparts when assessed at their natural heights. These differences largely disappeared when the dwarf isolines were physically raised so that their spikes were positioned at the same height as those of their respective tall counterparts. The effects of plant height on type II resistance was less clear. For those NIL pairs which showed significant differences, it was the dwarf isolines which gave better resistance. As the Rht genes involved in these NILs locate at different genomic regions, the differences in FHB between the dwarf and tall isolines are unlikely to be the result of linkages between each of the different Rht loci with a beneficial or a deleterious gene affecting type I or type II resistance. Rather, the different FHB resistances are probably caused by direct or indirect effects of height difference per se, and microclimate may have contributed to the better type I resistance of the tall plants. Thus, caution should be exercised when attempting to exploit any of the FHB resistant loci co‐located with Rht genes. |
| |
Keywords: | Fusarium graminearum fusarium head blight near‐isogenic lines Rht genes Triticum aestivum wheat scab |
|
|