Environmental effects on phenotypic variation in plants Christopher Barrington1, Simon Engledow1, Hamad Sidiqqui1, Claude Becker2, David Schafer1, Franziska Srocke1, Detlef Weigel2 and Jose Gutierrez-Marcos1 1School of Life Sciences, University of Warwick, UK 2MPI for Developmental Biology, Tubingen, Germany Background Aim of the project • Plants are sessile organisms and as such need to be able to rapidly adapt to their changing environment to ensure their survival. • To investigate stress-induced phenotypic variation in maize and identify the molecular mechanisms responsible for their inheritance in subsequent generations. • Environmental stress can influence plant growth and cause changes in appearance (or phenotype) that can be transmitted to the progeny, sometimes remaining stable for several generations. How this happens is not yet understood. Preliminary findings • Most phenotypic changes induced by heat stress are not associated with changes in DNA sequence, but in the way the DNA is chemically modified and packaged in each cell, and are known as “epigenetic changes”. WT Figure 1. Acquired resistance to stress in maize. Left hand side, plants derived from seeds exposed to high temperature. Right hand side, control plants derived from seed propagated in standard growth conditions. polIV rdr2 Figure 2. Stress tolerance in maize is regulated epigenetically. Left panel, maize mutant plants with defective epigenetic machinery are more sensitive to heat stress when compared to wild-type (WT). Right panel, representation of the maize genome showing epigenetic changes induced by heat stress (blue bars). • U n d e r s t a n d i n g h o w t h e s e s o - c a l l e d environmentally-induced phenotypic traits are generated and their mode of inheritance is important, as they represent an unexplored source of variation that can contribute to the development and breeding of more robust crop plants. • We have found that only a small fraction of the identified epigenetic changes are inherited in the next generation. • Maize plants represent a good model system to study this phenomenon, as they can produce a variety of recognizable traits in response to a wide range of environmental conditions, such as heat or drought, which they can remember. • To determine which genes are important in regulating the inheritance of acquired phenotypic variation induced by temperature stress. Future work Warwick Crop Centre www.warwick.ac.uk/go/wcc