THE CLIMACTERIC RESPIRATION RISE IN ATTACHED AND DETACHED TOMATO FRUIT

The classification of tomato fruit as climacteric, exhibiting a characteristic rise in respiration during ripening, has been questioned. A recent investigation using a static gas collection system has suggested that only detached fruit show a peak in respiration, whilst no such rise was evident in tomato fruit attached to the plant. The associated rise in ethylene production during ripening was confirmed in both attached and detached fruit. Using a continuous flow system to measure respiration rates of tomato fruit (Lycopersicon esculentum Mill. cvs. Counter and Sweet 100), a respiration rate increase of approximately 100% was observed during ripening whether fruit were detached from or attached to the vine. These results support the concept that tomato is a climacteric fruit. The contrast between results presented here and those presented recently on a cultivar of processing tomato (cv. Castlemart), may indicate a difference in climacteric behaviour among cultivars, or unrecognised flaws in the different methods of measuring CO2 evolution from tomato fruit.