Resumen

FUCHS, Morela et al. Efecto de la radiación gamma sobre la diferenciación de plantas de caña de azúcar a partir de callos¹. Agronomía Trop. [online]. 2002, vol.52, n.3, pp.311-324. ISSN 0002-192X.

Summary With the objetive of inducing mutation in sugarcane, Saccharum sp., in order to obtain disease resistant plants, the effect of gamma radiation on plants regenerated in vitro from calluses was evaluated. Five varieties were chosen, B6749, B7987, PR62258, B4362 and PR641791, the first three susceptible to the mosaic of sugarcane and the last two susceptible to rust. Organogenic calluses of these varieties were irradiated with five doses of gamma rays: 0, 2, 4, 8 and 12 kR. The radiation effect on the differentiation of plants was evaluated at 90, 120 and 150 days. Regenerated plants were transplanted to soil in greenhouse condition to determine survival index. Variance analysis of differentation data showed significant differences between varieties and doses. B6749 had largest differentiation value followed by B4362. Based on the distribution of frequencies of the different degrees of differentiation for each variety and doses, the LD50 was established for each variety, being in a range of 2 kR for more sensitive varieties and between 4 and 8 kR for the less sensible ones. Doses between 2 and 4 kR may be used with good possibilities of obtaining acceptable mutation indexes

Palabras clave : Saccharum spp; mutation; gamma radiation;; differentiation; callus.