Genetic mining of desirable alleles for transgenerational stress memory through enhancing drought adaptation in wheat

Abstract

Plant memory refers to the phenomenon where past environmental experiences influence the responses of plants to current/future events. Drought stress has a mostly significant negative impact on wheat, which is a vital crop for global food security. In the context of germination, plant memory can manifest as 'transgenerational priming', where mother plants exposure to drought stress alters the germination behavior of the next-generation seeds. Therefore, our study aimed to explore the genetic factors underpinning transgenerational drought tolerance in wheat using a diverse collection of 111 by the Genome-Wide Association Study (GWAS). In the seed germination test, all genotypes had higher Germination Percentage (G%) and Germination Pace (GP) from seeds of Stressed Plants (OSP) than those of Non-Stressed Plants (ONP) by 16% and 29%, respectively), indicating that Transgenerational Stress Memory (TSM) may manifest through appearing to possess a more persistent stress memory. For root length, OSP had a greater Root Length (RL) than ONP by 45%, suggesting a more highly developed root system in the OSP seeds. The time at which TSM manifests during the plant life cycle could reflect disparate strategies of TSM duration among genotypes from OSP and ONP. Genetic associations of TSM showed highly significant QTNs for all of the studied traits. For instance, a highly significant QTN (BS00068042_51) located on chromosome 2B at position 107,381,860 bp inside the gene TraesCS2B02G140800 encodes Cytochrome P450 (CYPs) that was found to be associated with the traits of FW and SMC for OSP. CYPs play a significant role in wheat response to environmental stresses. Therefore, further research into the specific alleles/candidate genes and their functions in wheat transgenerational stress memory will provide valuable insights for developing strategies to enhance drought tolerance in wheat crops through genetic manipulation or targeted interventions.