NELSON BARBOSA MACHADO-NETO published this homemade media.
Methods and Materials
An experiment with starch as gelling agent was done. Media constituents were coconut water (100ml.l-1), 2g.l-1 of commercial fertilizer with 6:9:6 N:P:K concentrations, 20g .l-1 of sucrose, 100g.l-1 of banana pulp and four cherry tomatoes. Two kinds of starch were tested, maize and cassava, both cheap and easy to find. The starch concentrations were 70, 90 and 110g l-1. Seeds were disinfected, in a syringe, with calcium hypochlorite at 0.5% concentration, washed twice with sterile water and sowed (Figure 2). Two types of caps were used to cover the flasks, a metal or a polypropylene (Figure 1). After two months seedlings were replanted (Figure 3) in the same media with the aid of a forceps disinfected with 1% calcium hypochlorite.
Results
Media made with cassava starch did not reach the solid gel state, it was viscous even with 110g.l-1 , which did not allow sowing. Maize starch media remained hard and seedlings, when planted in it, grows well. In spite of that medium is not equilibrated in the composition (Table 1) it is suitable for sowing and growing orchids from seed, especially Cattleya and their relatives and Oncidium.
Both caps used, the metal or polypropylene, showed very good results. The metal cap, however, after successive sterilization processes, became oxidized and it could liberates some iron oxide to the media, which could be toxic for some species.
The results obtained was better when just a few seeds were sown, around 40-50 per flask, and this is facilitated by sowing with a syringe.