Transgenerational stress memory in seed and seedling vigor of peanut (Arachis hypogaea L.) varies by genotype.

• Water deficit during vegetative growth impacts seed vigor in peanut. • Two subspecies of peanut differ in when transgenerational stress memory manifests. • Transgenerational stress memory altered root architecture in two genotypes. • Phenotypes associated with stress memory cannot be generalized within species. Recent studies in plants and other organisms have suggested that 'memories' of stress events can be inherited from parent to offspring through a process known as transgenerational stress memory (TSM). However, TSM has not been adequately studied in many plant species, despite its potential role in stress adaptation. The objective of this study was to identify the effects of TSM on the development and vigor of peanut (Arachis hypogaea L.) seedlings of five genotypes. Seeds were collected from parents that received two water regimes representing contrasting TSM: 1) offspring from non-stressed parents and 2) offspring from stressed parents. Seed weight and vigor were tested using traditional methods, and both above- and belowground seedling vigor were analyzed using a rhizotron bioassay. There was a high variability between genotypes in how and when TSM was expressed, as illustrated by an interaction of offspring type and genotype in characteristics such as initial seed weight, germination, and rooting characteristics. These results contribute important documentation of the existence of TSM in plants and the need to further examine TSM capacity in plant adaptation to stress. Further, these results suggest that, for certain genotypes, water availability in the parent generation could be responsible for increased seed quality and vigor. [ABSTRACT FROM AUTHOR]