Abstract
A study was carried out to elucidate the efficacy of different bacterial strains on controlling detrimental bacteria and on vase
life extension of Gladiolus L. hybrids ‘Mammoth’. In a preliminary study, three bacterial strains (Bacillus pumilus, Delftia
acidovorans, and Herbasperillum sp.) were isolated from the vase solutions of cut Gladiolus, identified and cultured to obtain
the bacteria to be used in the study. These isolated strains were compared with two strains of Pseudomonas fluorescens (PF279 and PF-417). All tested strains produced similar vase life of cut gladiolus stems, which was also similar to that of stems
placed in tap water. However, stems placed in solutions with PF-279 Pseudomonas fluorecsens resulted in highest water
uptake, while the stems placed in solutions with higher concentrations of Herbasperillum sp. (10 or 20 mL L-1
) had lowest
water uptake. Cut stems require low pH for sustaining water uptake and vase life extension, but use of nutrient broth to culture
bacteria increased initial solution pH, which resulted in early senescence of cut stems due to rapid bacterial growth, vascular
occlusion due to embolisms and reduced stem hydraulic conductance compared to the stems placed in tap water (control). In
summary, tested bacterial strains had no effect on controlling detrimental bacteria present in the vase solutions or vase life
extension of cut gladiolus and cannot be used in organic floral preservatives for holding cut stems after harvest.
