Somatic embryogenesis and the effect of particle bombardment on banana Maçã regeneration

Abstract

-A plant regeneration method with cell suspension cultures of banana, and the effect of biobalistic on regeneration potential are described in this report. Somatic embryos of banana were obtained from indirect embryogenesis of male inflorescence of banana cultivar Maçã (AAB group). Part of the calluses formed (40%) showed embryogenic characteristics (nonfriable, compact and yellow color). The cell suspension, originated from embryogenic calluses, contained clusters of small tightly packed cells with dense cytoplasms, relatively large nuclei and very dense nucleoli. After four months of culture, somatic embryos started to regenerate. The maximum number of regenerated plants was observed between 45 and 60 days after embryo formation. In the first experiment, 401 plants were regenerated from approximately 10 mL of packed cells. In the second experiment, 399 plants were regenerated from a cell suspension six months older than that of the first experiment. Cell transformation using particle bombardment with three different plasmid constructions, containing the uid-A gene, resulted in a strong GUS expression five days after bombardment; however, plant regeneration from bombarded cells was much lower than nonbombarded ones.Index terms: Musa, cell suspension, callus, somatic differentiation, biobalistic. Embriogênese somática e o efeito do bombardeamento de partículas na regeneração de banana cv. MaçãResumo -Neste trabalho é descrito um método de regeneração de plantas, a partir de células de bananeira, em suspensão, e o efeito da biobalística no potencial regenerativo. Embriões somáticos foram obtidos de inflorescências masculinas de bananeira cv. Maçã (grupo AAB) por meio de embriogênese indireta. Parte dos calos (40%) apresentou características embriogênicas (não-friáveis, compactas e amareladas). Suspensões celulares obtidas desses calos continham pequenas massas celulares, com citoplasmas ricos em grânulos de amido, núcleos grandes e nucléolos densos. Termos para indexação: Musa, suspensão celular, calos, diferenciação somática, biobalística.

Cell suspension culture and plant regeneration of a Brazilian plantain, cultivar Terra

“…Somatic embryos with similar features have been previously reported (Côte et al, 1996;Navarro et al, 1997;Khalil et al, 2002;Jalil et al, 2003). At 5-6 months of culture, 20% of the explants produced embryogenic calli (Figure 1 B).…”

“…When the cell suspensions were 4-5 months old, fi ne embryogenic cells were observed as yellowish white in color. The yellow pigmentation of cytoplasm indicated the embryogenic character of the cell suspensions (Ganapathi et al, 2001;Jalil et al, 2003). The number of cells had doubled at every subcultivation period.…”

“…through nonconventional strategies, i.e. protoplast culture and fusion, mutagenesis, somaclonal variation and genetic transformation (Ganapathi et al, 2001;Matsumoto et al, 2002;Assani et al, 2005;Houllou-Kido et al, 2005;Kumar et al, 2005;Pei et al, 2005). In addition, the incorporation of biotechnological procedures in breeding programs depends upon effi cient and reliable plant regeneration protocols.…”

Genetic Improvement of Tropical and Subtropical Fruit Trees via Biolistic Methods

“…Transgenic Crops -Emerging Trends and Future Perspectives Embryogenic cells initiated from different tissues including immature male flowers [16], immature embryos [17], male inflorescence, and buds [18] were reported with high potential to gene transformation in banana and plantain. A protocol optimized for transient and stable transformation of the uidA gene in banana cells using a special gene gun is illustrated by [14].…”