This work researched the effects of the 10, 20, 30 and 40 g L-1 sucrose concentration, added to MS nutrients solution
of Murashige and Skoog (1962), at 50 and 100%, and those of the temperatures of a growing room at 18°C and 25°C,
in the in vitro conservation in three BAG-amaryllis accesses (Hippeastrum Herb.), of Instituto Agronômico (IAC).
The stalk terminal buds of ‘Apple Blossom’, ‘Red Lion’ and ‘Orange Sovereign’, containing 02 primordial foliages,
were extracted from bulbs, which were treated with thermotherapy at 37°C for 40 days. Analyses of viral particles
from the three cultivars leaves, cultivated in field and in vitro, were carried out. The experimental setting adopted was
entirely casual, in a factorial scheme of 2 x 3 x 2, consisting of 12 treatments, 10 repetitions and 01 explant per sample.
It was noticed that the association of thermo therapy with the in vitro culture reduced the presence of viral particles
by 70, 65 and 55% for ‘Orange Sovereign’, ‘Red Lion’ and ‘Apple Blossom’, respectively. Explants from the three
amaryllis cultivars reached the smallest development when cultivated in MS medium (50%), to which was added 10
g L-1 of sucrose, and which was incubated at 18°C, keeping their viability for at least 90 days. On these conditions,
the explants developed, on average, 01 bulb with 2,2; 2,0 and 2,3 leaves 32,5; 27,8 and 25,8 cm long; 1,7; 2,3 and 2,0
roots of 20,5, 16,8 and 18,2 cm and fresh mass of 3,9; 3,4 and 3,1g, for ‘Apple Blossom’, ‘Red Lion’ and ‘Orange
Sovereign’, respectively.