Maternal effects should be considered in the establishment of forestry plantations

Breeding strategies for plants focus on the genetic influence on their phenotypes. However, the phenotype is not only the outcome of the genotype or the environmental conditions under which plants grow. It is important to also recognise that the maternal environment has a significant effect on the phenotype of the offspring. These maternal effects represent a transgenerational form of phenotypic plasticity, transmitted to the progeny without modifications in the DNA sequence. These can influence the development, disease and pest resistance, and fitness of the offspring and subsequent development of the mature plant. In this review, we define and synthesize current understanding of maternal effects in plant reproduction and discuss evidence for the role of these effects in plants and more specifically in trees utilised for plantation forestry. We highlight the implications of the maternal environment in the management of forestry seed orchards and discuss approaches to study maternal effects in order to enhance the productivity of forestry plantations.