Changes in the alkaloid content of developing fruits of tomato (Lycopersicon esculentum Mill.): I. Analyses of cultivars and mutants with different ripening characteristics

Normal ripening red-, orange- and yellow-fruited cultivars of tomato showed similar patterns of fruit growth and tomatine accumulation to those of non-ripening mutants. In all fruits, the tomatine concentration declined continuously from an early stage although the absolute amount per fruit showed a biphasic pattern of accumulation and decline. The turning point' occurred at an earlier developmental stage in normal fruits than in mutants. Normal fruits also had a lower initial and higher final tomatine content than mutants on a per fruit basis although, on a unit weight basis, their initial concentration was higher and final concentration lower. Small, prematurely-ripened red fruits had alkaloid levels intermediate between large, unripe, green fruits and large, ripe, red fruits. It is concluded that growth and ripening processes may both contribute to the decline in fruit tomatine.