Fruit ripening in Actinidia sp(kiwifruit)is complex,and atypical.Many of the fruit ripening associated processes(starch breakdown,flesh colour change,and initial softening)occurs in the absence of detectable ethylene.Late in fruit development,autocatalytic ethylene is produced,and a second ripening process(aroma volatile production and further softening)occurs.Actinidia chinensis,are perennial vines,flowering in spring,shortly after budbreak.The fruit grows over the spring and summer and,ripens slowly in autumn.Cold temperature can accelerate the first phase of ripening,and during this phase ripening can be accelerated with exogenous ethylene.Building on the tomato fruit ripening model we have shown that the NON RIPENING(NOR)like genes and MADS box genes such as RIPENING INHIBITOR and TDR4/FUL play a key role in the control of fruit ripening.Two kiwifruit NOR like genes,with ripening associated expression were identified.One which partially complements the tomato nor mutation and one that fully complements.The closest kiwifruit RINlike gene does not complement the tomato rin mutation,but shows a RIN like increase in expression during ripening,and an increase with exogenous ethylene.Unlike tomato,kiwifruit RIN cannot activate its own promoter providing us with a model to describe the two phases of ripening in kiwifruit.