|Kim, Woojae - Rural Development Administration - Korea|
Submitted to: Mid Atlantic Plant and Molecular Biology Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2019
Publication Date: 8/13/2019
Citation: Barnaby, J.Y., Kim, W., Ziska, L.H., Fleisher, D.H., Reddy, V., McClung, A.M. 2019. Exploring naturally exisiting genetic variation in grain chalk formation in response to changing climate. Mid Atlantic Plant and Molecular Biology Proceedings.
Technical Abstract: The presence of grain chalk, opaque white areas in the rice grain, can reduce milling and cooking quality as well as grain appearance, thus reducing the value of the crop. Over the last several years, the USA rice industry has been concerned about the increasing prevalence of undesirable chalky rice which is resulting in a loss of some international markets. Heat stress is also known to significantly increase grain chalkiness which reduces milling quality, cooking properties, and grain appearance. To identify genotype (G) x environment (E) impact on chalk formation and to inform future breeding efforts toward low chalk varieties, two parents, Kaybonnet and ZHE733, displaying contrasting % chalk formation and 7 recombinant inbred lines (RIL) possessing 3 major chalk quantitative trait loci (QTL) were grown under ambient CO2 and an elevated atmospheric level projected for 2050, and using two temperature regimes, one with warmer temperature during grain fill stage. Two experiments, one in growth chambers, and the other in greenhouses, were conducted. Our results showed natural genetic variation in heat-induced chalk formation in response to future anticipated climate scenarios, high temperature with elevated atmospheric CO2. These results will assist breeders use marker assisted selection for development of new climate resilient varieties that will minimize chalkiness while maintaining economic value.