Project Number: 3096-21000-022-01-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jan 1, 2016
End Date: Dec 31, 2019
1. Quantify the natural variation in heat stress response across a diverse set of maize inbred lines and identify underlying mechanisms through integrating analysis at the gene-expression, biochemical, and whole-plant level, 2. Identify the genetic loci that contribute to the differential heat stress response of three representative maize inbred lines through QTL analysis of two populations
A set of 24 diverse accessions will be selected from 600 maize germplasm. These accessions showed significant difference in heat stress response at early, mid, and late season: plant death, leaf bleaching, leaf firing, tassel barren, tassel blasting, and delay of silking. We plan to conduct genome-wide transcriptional profiling through RNA-seq by subjecting this set of 24 maize accessions to the controlled heat stress condition that produces similar rankings to available field screening findings. Gene expression network will be constructed and compared with established networks in model plant species. Membrane lipid profiling will be conducted to examine the roles of phosphatidic acid (PA) on heat stress response and to validate the potential correlation of PA with heat tolerance traits across the diverse genetic backgrounds. In addition, three mapping populations from a chain-cross design will be advanced to recombinant inbred lines (RILs) for field-based phenotyping of heat stress response and subsequent mapping. Genotyping-by-sequencing will be applied to obtain SNPs for meta-QTL analysis of these RIL populations.