Barley seedling, alkaloids

Hobdeum. Hordenine is not present in the fruit of barley but makes its appearance during germination. It is first demonstrable in meriste-matic root tissue. It is produced without an outside source of nitrogen and has its origin in tyrosine—clear proof that at least some of the building blocks of alkaloids are derivable from proteins. Its concentration rapidly reaches a maximum, and it disappears after one month (372). Seedlings of Panicum miliaceum L. behave in the same way (373). 

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