The increase in prices of imported products, particularly the laboratory supplies, especially agar, very common in the
preparation of culture media for the growth of pathogens, imposes the search for alternatives that will replace it. The
objective was to evaluate the Maizina Americana
® and sagú flour (
Maranta
sp.) as gelling agents to replace the agar in
culture medium potato dextrose agar (PDA). The maizina was used at a dose of 50, 75, 100 and 125 g.L
-1 and sagú, in doses
of 50, 60, 70, 80 and 90 g.L
-1. Completely randomized experimental design was employed, each experiment with five
treatments and four replicates and four capsules of Petri per experimental unit; a control treatment was placed on each trial
with PDA. For all doses of Maizina Americana
® and sagú, half a litre of the decoction of 200 g of potato and 20 g of
sucrose per litre of culture medium was used. The evaluation of these media was performed by measuring the growth of the
fungus
Rhizoctonia solani
at 24, 48 and 72 hours. According to the results obtained, the best maizina dose was 75 g.L
-1 and
in the case of the sagú, it was 90 g.L
-1. Both products can be used as solidifying agent in the culture media replacing the
agar, with a consequent benefit of the costs of media preparing and without negative effects on the growth of
R. solani.
