In vitro germination of seeds and acclimatization of Macambira (Bromelia laciniosa Martius ex Schultes f.) seedlings

Abstract

The macambira is an ornamental plant that has a high degree of ecological importance. The objective in this research was to evaluate the in vitro germination of macambira in different culture media and establish the best substrate for the acclimatization of micropropagated plants. Five treatments were tested: 0, 25, 50, 75, and 100% salt of Murashige and Skoog (MS) medium. We calculated the percentage of germination and germination speed index (GSI). For testing acclimatization, five combinations of substrates were evaluated: coconut coir : earthworm castings (2:1); coconut coir : earthworm castings: sand (1:1:1, 2:1:1 and 2:2:1); and vermiculite : earthworm castings (2:1). There was no difference between the concentrations of MS salts based on the percentage of germination. For the GSI, the treatment 100% MS salts had the poorest results. There was no significant difference in the acclimatization of seedlings for the variables number of leaves and dried mass of roots and shoots. For the variable length of the longest root, coconut coir: earthworm castings (2:1) and coconut coir : earthworm castings : sand (2:1:1 and 2:2:1) had the highest averages, and for dried root mass, the coconut coir : earthworm castings : sand (1:1:1 and 2:2:1) provided the best results. Germination can be carried out in vitro in a medium containing only water and agar, and for acclimatization, the substrate coconut coir : earthworm castings : sand (2:2:1) should be used.