Cultivo de embriões imaturos de citros em diferentes concentrações de carvão ativado e ácido giberélico

Abstract

Activated charcoal and gibberelin provides better conditions on development of citrus immature embryos. Activated charcoal and GA3 (gibberelic acid) on 'Pêra Rio' sweet orange x 'Poncã' mandarin immature embryos culture was evaluated. After 118 days-pollination, imature fruits with 3 to 4 cm of diameter were collected, seeds removed and treated with alcohol (70%) for five min., sodium hypoclorite (2%) for 20 min. and three times washed with distilled and autoclaved water. In aseptic conditions, the teguments were separated, the globular embryos excised and inoculated in test tubes containing 15 mL of the MT medium culture, added of activated charcoal (0; 0.5; 1; 1.5 and 2 g L-1) and GA3 (0; 0.01; 0.1; 1 and 10 mg L-1). After inoculation, the embryos were maintained for 90 days in growth room at 27+1ºC, 16 hours photoperiod and 32 mmol m-2 s-1 irradiance. Higher length of the aerial part was obtained in MT medium added 0.01 and 1 mg L-1 of GA3 combined with 2 g L-1 of activated charcoal. Higher length of the roots system, fresh mass and number of leaves of seedlings was obtained in MT medium added 0.01 mg L-1 of GA3 and activated charcoal absence. Addition of activated charcoal influenced in giberellic acid concentration added in MT medium.