|CASTILLO-GONZALEZ, SONIA - ARKANSAS STATE UNIVERSITY|
|TIBBS, MOLLY - ARKANSAS STATE UNIVERSITY|
|WILKIE, AUSTIN - ARKANSAS STATE UNIVERSITY|
|MCCOUCH, SUSAN - CORNELL UNIVERSITY - NEW YORK|
|LORENCE, ARGELIA - ARKANSAS STATE UNIVERSITY|
Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/1/2016
Publication Date: 7/2/2017
Citation: Castillo-Gonzalez, S.E., Tibbs, M., Wilkie, A., Yeater, K.M., Edwards, J., McClung, A.M., Eizenga, G.C., Mccouch, S.R., Lorence, A. 2017. Assessing foliar ascorbate content in the rice diversity panel 1. Proc. 36th Rice Technical Working Group Meeting, Galveston, TX, p. 77. March 1-4, 2016. CDROM.
Technical Abstract: Early spring plantings of rice can have poor stands due to cold temperatures. Our previous studies have shown that high vitamin C (ascorbate AsA) Arabidopsis lines are tolerant to cold stress. The rice diversity panel 1 (RDP1) represents the genetic diversity of Oryza sativa and has been extensively phenotyped and genotyped. We hypothesized that there are genetic differences in the RDP1 for foliar AsA content, and that high AsA content is associated with cold tolerance in rice at the germination stage. We determined significant differences (p< 0.05) in seedling foliar AsA content in the RDP1 which ranged two fold. To assess the correlation between AsA content with cold tolerance, we exposed 12 accessions that were high or low in foliar AsA, as compared to the Nipponbare check, to cold stress at the germination stage. Two out of three (66.7%) high AsA accessions were cold tolerant, whereas only three out of nine (33%) low AsA accessions were cold tolerant, as established by coleoptile length reduction (coleoptile at 12°C/coleoptile length at 30°C). While high AsA content is not the only factor in conferring cold tolerance, our results indicate that ascorbate supports this tolerance. We also associated the results of foliar AsA content by subpopulation using genome wide association studies (GWAS). Results from this analysis indicate that hits on chromosome 5 and 2 are promising genomic regions that can be further studied to identify candidate genes likely involved in the synthesis, degradation, or regulation of ascorbate content in rice at the seedling stage.