Resumo

TORROBA, MC; PACCAPELO, HA; AGUILERA, L  e  MAZZOLA, J. Plant micropropagation in experimental lines of forage maize coming from crossing Zea mays L. and Zea diploperennis Iltis, Doebley and Guzmán. Phyton (B. Aires) [online]. 2008, vol.77, pp.93-102. ISSN 1851-5657.

An optimized methodology for improving regeneration of maize plants by direct organogenesis was evaluated. Our objective was to obtain genetically homogeneous plants through in vitro methods to regenera-te clumps of multiple shoots from shoot tips at high frequency. Cultures were initiated from shoot tips of experimental lines of maize on a Murashige & Skoog (MS) medium supplemented with 2 mg/l benziladenine. Two experi­mental forage maize lines were used, in which two frequencies of subcultu-res were evaluated, namely line L. 850 (every 15 or 30 days) and line L.769 (every 30 days). It was observed that the highest rate of regeneration in line L.850 was reached in the second subculture (1.8 plants) with subculture every 30 days, and in the fifth subculture (1.8 plants) with subculture every 15 days. In line L.769, the highest frequency of regeneration was reached in the fourth subculture (1.7 plants). Regeneration rates were low compared with somatic embryogenesis, but no somaclonal variations were detected in field plant phe-notypes; a marked uniformity was detected within lines.

Palavras-chave : Micropropagation; Regeneration rate; In vitro culture; Benziladenine; Forage maize; Zea mays L.; Zea diploperennis I; D & G.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )