Resumo

VARGAS ARAUJO, Jesús et al. Reproductive characteristics of nine varieties of poinsettia (Euphorbia pulcherrima, Willd. ex Klotzch). Rev. Mex. Cienc. Agríc [online]. 2017, vol.8, n.2, pp.295-306. ISSN 2007-0934.  https://doi.org/10.29312/remexca.v8i2.51.

Mexico is the center of origin of the poinsettia (Euphorbia pulcherrima, Willd. ex Klotzch), however, production depends on the varieties generated in other countries because they do not have national varieties. For genetic improvement of any kind study of reproductive biology is necessary. Based on the above, the objective of this research was to evaluate the reproduction of three varieties of poinsettia of sun (Bethlehem, John Paul, Christmas Dawn) and six cultivars of shadow (Freedom, Prestige, Ice Punch, Nutcracker white, Sonora White glitter and Burgundy) to define the bases of breeding methods. The viability of pollen was determined by staining with aceto-carmine and pollen germination; the schedule was studied when the flowers were receptive, applying a drop of H2O2 on stigma; four treatments were established to determine the type of pollination of the poinsettia plants. The research was developed in a completely randomized design. An analysis of variance and mean comparison test with Tukey test (p≤ 0.05). Was performed. The viability of pollen varied from 68 to 93%. The greater receptivity of the stigma was observed at 14:00 h. The sun varieties could act as females in a breeding program because of greater viability of pollen, receptive flowers, and fruit binding. The Nutcraker White and Prestige varieties showed no stigma receptivity or fruit binding. It was determined that the pollination type of the poinsettia was crossed.

Palavras-chave : poinsettia; stigma receptivity; type of pollination; pollen viability.