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Phytoplasma induced free-branching in commercial poinsettia cultivars


Free-branching poinsettia cultivars that produce numerous axillary shoots are essential for propagating desirable multi-flowered poinsettias (Euphorbia pulcherrima Wild. Klotz). For more than a decade, a biological agent has been suspected to cause free-branching in poinsettias. Attempts to identify the branching agent have failed. Isolation of the pathogen was accomplished using a living host and it was concluded that an unculturable phytoplasma is the cause of free-branching in poinsettias. This is the first reported example of a pathogenic phytoplasma as the causal agent of a desirable and economically important trait.

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Lee, IM., Klopmeyer, M., Bartoszyk, I. et al. Phytoplasma induced free-branching in commercial poinsettia cultivars. Nat Biotechnol 15, 178–182 (1997).

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