DECUSSATEnetwork with flowering genes explains the variable effects ofqDTY12.1to rice yield under drought across genetic backgrounds

Abstract

The impact of qDTY12.1 in maintaining yield under drought has not been consistent across genetic backgrounds. We hypothesized that synergism or antagonism with additive‐effect peripheral genes across the background genome either enhances or undermines its full potential. By modeling the transcriptional networks across sibling qDTY12.1‐introgression lines with contrasting yield under drought (LPB = low‐yield penalty; HPB = high‐yield penalty), the qDTY12.1‐encoded DECUSSATE gene (OsDEC) was revealed as the core of a synergy with other genes in the genetic background. OsDEC is expressed in flag leaves and induced by progressive drought at booting stage in LPB but not in HPB. The unique OsDEC signature in LPB is coordinated with 35 upstream and downstream peripheral genes involved in floral development through the cytokinin signaling pathway. Results support the differential network rewiring effects through genetic coupling–uncoupling between qDTY12.1 and other upstream and downstream peripheral genes across the distinct genetic backgrounds of LPB and HPB. The functional DEC‐network in LPB defines a mechanism for early flowering as a means for avoiding the drought‐induced depletion of photosynthate needed for reproductive growth. Its impact is likely through the timely establishment of stronger source‐sink dynamics that sustains a robust reproductive transition under drought.

Haplogenic quantitative effects regulate flooded germination, subsequent water deficit stress, and recovery in direct seeded rice

“…Thus, further characterization of these two candidate genes (WAK79 andMRLK59 ) would provide mechanistic insights into the interaction between TPP7 and Sub1 with respect to cell wall elongation and haplogenic regulation of tolerance. In support of the 'haplogenic model', a major drought tolerant QTL in rice, qDTY12.1 also has a set of genes namely NAM and Decussate genes within the QTL region (haplogenic region) regulating the drought stress response in rice (Sanchez et al, 2022). Thus, the 'haplogenic model' and regulation of complex traits could be highly prevalent in rice and other plants.…”