S. Mederos Molina
Hypericum canariense L. is an endemic specie of the Canary Islands and belongs to the Hypericaceae family. Furthermore, this specie is extensively used in the pharmaceutical industry. During in vitro establishment of many species - including Hypericum canariense L. - brown exudates are detrimental to the future development of this plant material (1).

The purpose of this work was to prevent the brown exudate that diffuses in the culture medium during in vitro establishment of shoots and furthermore to determine the culture medium for shoot development and proliferation. Initial explants issued from the shoot apex and axillary buds were taken from mature plants. The explants were collected from sprouts during the months of May and June. To avoid the oxidative browning of the explants and also of the culture media, the fragments were rinsed in a water solution or in a solutions containing a natural antioxidants -rosmanol or carnosic acid- for six, twelve and twenty four hours. On the other hand, the rosmanol and carnosic acid were added separately to the culture medium at the same concentrations that we used before. This natural products were isolated from Salvia canariensis L. (2) (Lamiaceae family). As well this specie is an endemic plant to the Canary Islands. Cultures were maintained under a 16 hr photoperiod (20 μExm-2xs-1) and at temperature of 24°C. All experiments were repeated twice.

The results showed that the contamination was visible only in the explants rinsed by immersion prior to culture. Similar observations have been reported from other species (6). Soaking the explants in pretreatments with water solution; solutions containing rosmanol or carnosic acid was not effective and also it sem that the immersion of explants under this anaerobic conditions was detrimental for the in vitro culture of the explants. However, oxidative browning was supressed when the Almácigo medium (3) (5) was supplemented with rosmanol.

The in vitro establishment from shoots of Hypericum canariense L. was achieved in Almácigo medium (3) (5).

Mederos Molina, S. (1991). "IN VITRO" GROWTH AND MULTIPLICATION OF HYPERICUM CANARIENSE L.. Acta Hortic. 289, 133-134
DOI: 10.17660/ActaHortic.1991.289.30

Acta Horticulturae