Location: Hard Winter Wheat Genetics ResearchTitle: A novel nitrogen-dependent gene associates with the lesion mimic trait in wheat
|LI, LEI - Yangzhou University|
|SHI, XUAN - Yangzhou University|
|ZHENG, FEI - Yangzhou University|
|LI, CHANGCHENG - Yangzhou University|
|WU, DI - Yangzhou University|
|GAO, DERONG - Yangzhou University|
|WU, JINCAI - Yangzhou University|
|LI, TAO - Yangzhou University|
Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2016
Publication Date: 7/26/2016
Publication URL: http://handle.nal.usda.gov/10113/5491318
Citation: Li, L., Shi, X., Zheng, F., Li, C., Wu, D., Bai, G., Gao, D., Wu, J., Li, T. 2016. A novel nitrogen-dependent gene associates with the lesion mimic trait in wheat. Journal of Theoretical and Applied Genetics. doi:10.1007/s00122-016-2758-3.
Interpretive Summary: Lesion mimic (LM) refers to small yellow or brown leaf spot symptoms appearing spontaneously on leaf tissue when plant pathogens are absent. LM has previously been correlated with broad-spectrum resistance to leaf rust disease. We investigated a LM wheat line for its responses to nitrogen application and found that LM is nitrogen-responsive and nitrogen-dosage dependent. We mapped a nitrogen-dependent LM gene to a region in the short arm of chromosome 2B and identified a DNA marker for the gene. This gene could be useful in breeding for broad-spectrum resistance in wheat.
Technical Abstract: Lesion mimic (LM) refers to hypersensitive reaction-like (HRL) symptoms that appears on leaf tissue in the absence of plant pathogens. In a wheat line P7001, LM showed up on the leaves under the 0 g nitrogen (N) treatment, but disappeared when sufficient N was supplied, suggesting that LM is N-responsive and N-dosage dependent. Using bulked segregant analysis (BSA) strategy together with RNA-seq and DNA markers, we identified a N-dependent LM gene (Ndhrl1) and mapped it to the short arm of chromosome 2B using an F5 recombinant inbred population developed from the cross of P7001× P216. The putative gene for LM was delimited into an interval of 8.1 cM flanked by the CAPS/dCAPS markers 7hrC9 and 7hr2dc14, and co-segregated with the dCAPS marker 7hrdc2. This gene is most likely a novel gene for LM in wheat based on its chromosomal location. Further analysis of RNA-seq data showed that genes in plant-pathogen interaction, nitrogen metabolism, zeatin biosynthesis and plant hormone signal transduction pathways were significantly differentially expressed between LM and non-LM lines.