Bacterial contamination in Ilex dumosa (aquifoliaceae) cultures: antibiotic treatment.

LUNA, C.; COLLAVINO, M; SANSBERRO, P.; MROGINSKI, L.

Faro, Portugal

Congreso; 3rd International Symposium on Acclimatization and Establishment of micropropagated Plants; 2007

International Society for Horticultural Science (ISHS)

A range of commercially antibiotics were tested on nodal segments-culture of Ilex dumosa for their ability to control bacterial (Gram negative) contamination. 13 treatment with 4 antibiotic were tested: Streptomycin(200 mg·ml-1), Chloramphenicol (50 mg·ml-1), Cefotaxime (0.25, 0.50 and 1 mg·ml-1) and combinations between Ampicilline (200 mg·ml-1) + Chloramphenicol (50 mg·ml-1), Streptomycin(200 mg·ml-1) + Cefotaxime (0.50 mg·ml-1) ,  Cefotaxime (0.25, 0.50 and 1 mg·ml -1) + Ampicilline (200 mg·ml-1) or Chloramphenicol (50 mg·ml-1). Nodal segments of  I. dumosa were cultured in Murashige and Skoog (1962) medium, quarter strength  (1/4 MS), with 1,5% sucrose and 20μM BAP in a RITAÒ immersion temporal systems (with a frequency of 1 min. each 4 hr ) under 27 ± 2 ºC with lighting (cool white fluorescent light) at 116 μmol·m-2·s-1 and 14 hr photoperiod. After 30 days of culture various antibiotics controlled the proliferation of bacteria. The most suitable treatment was 0.50 mg·ml-1Cefotaxime which permitted 100% of establishment with 100% of explants with shoots with 8 cm in average. Rooting of regenerated shoots produced plants that were successfully transferred in pots.