Efecto de las sales inorgánicas del medio de cultivo en el crecimiento de pascuita (Euphorbia leucocephala Lotsy)

Abstract

Pascuita is a semi-cultivated euphorbiacea marketed as potted ornamental or for direct garden planting during Christmas. In Morelos México propagation is done by cuttings; however, its low yield is due to limited availability of plant material, poor quality, scarse rooting, and losses caused by rots. Therefore, it is necessary to evaluate other forms of mass propagation from healthy mother plants, selected by the number of inflorescences, bract size, bract color, and growth strength. This research determined the effect of in vitro inorganic salts promoting the most vigorous shoot growth of E. leucocephala. The effect of salts of culture media (MS 50 %, MS 25 %, WPMm, WPMm1, WPMm2 and WPMm3) without growth regulators was studied in a completely randomized experimental design. Shoot height, stem diameter, number of leaves, relative chlorophyll content and dry matter weight were recorded. Medium inorganic salts had a highly significant effect. The WMPm medium generated shoots with the largest diameter (1.35 mm), the highest chlorophyll content (41.44 Spad units), the highest dry matter weight (92.2 mg), as well as brightest green foliage and vigorous root production. By contrast, MS culture medium at 25 % strength caused less shoot growth and undesirable qualitative characteristics. It was concluded that the WPMm medium was the most suitable.