Host defence in a developmental context.

SUMMARY Disease resistance takes place within the context of the host developmental programme. The cellular and molecular basis of the developmental control of resistance is virtually unknown. It is clear from mutant studies that developmental processes are impacted when defence factors are altered and it is equally clear that alteration of developmental factors impacts defence functions. A review of current knowledge regarding the interplay of resistance and development is presented. Stage-specific limitations on defence represent an important target for crop improvement.