Potato tubers immature

Fruits of Atropa and Nicotiana are comparatively rich in alkaloids, hut tomatoes grown on Atropa or Nicotiana stock are almost devoid of alkaloids (298, 299), with the age of the stock seeming to have a slight effect (300). When mature or immature tomato fruits are injected with nicotine there is no apparent decrease with growth so that the lack of alkaloids in these fruits is not due to their breakdown (267). Potato tubers on Datura stock contain alkaloids but in lesser amount than the leaves. 

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