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The value of tetraploid plants of Vitis for breeding is known and such mutants occur spontaneously in vineyards and are noticeable mainly by enlarged bellies, thicker bunch stems, and darker green leaves.

Several mutants which appeared to be tetraploid were examined for polyploidy together with material from an apparently diploid Pinot Noir.

Polyploid Mutants in Grapes

1969, HortScience, vol 4, issue 3, pages 226 – 227

csiro 163

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