Resumo

MENDEZ, Eduardo. Effect of temperature, scarification and calcium concentrations on the germination of Gymnocalycium schickendantzii (F.A.C. Weber) Britton & Rose (Cactaceae). Rev. Fac. Cienc. Agrar., Univ. Nac. Cuyo [online]. 2011, vol.43, n.2, pp.103-109. ISSN 1853-8665.

Gymnocalycium schickendantzii (F.A.C. Weber) Britton & Rose is a species endemic to Argentina. In the province of Mendoza, populations of this cactus are not yet being affected by urban development and crops which could jeopardize its survival. Knowing the aspects of its germination might help explain the presence of this species in its natural habitat. The goal of the present study was to determine, by a germination assay of G. schickendantzii, the effect of temperature treatments of 20 and 30°C during 25 days in the laboratory, using 3 calcium concentrations (1, 10 and 20 meq/l Ca) and with water as control on seeds with and without scarification, under white light conditions. It was observed that germination percentages, with or without scarification, were significantly higher at 30°C than at 20°C. The scarification effect only helped to increase germination values when seeds were treated at 20°C. Calcium concentrations have a weak effect on seed germination under the same conditions. The times required for initiation of germination (IG) and to achieve 50% germination (T50) were longer at 30°C for both scarifed and non-scarifed seeds.

Palavras-chave : Gymnocalycium schickendantzii; Germination; Temperature; Scarification; Calcium concentrations; Argentina.

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