Influence of different treatments on the changes of flavone percentages in Ginkgo exocarps during postripeness

The effects of pre-picking exogenous hormones treatments, ambient temperature treatments and postripening treatments on the changes of flavone percentages in Ginkgo exocarps during postripeness were studied. The relationship between the changes of flavone percentages and respiration intensity, cell permeability, pectin methy-lesterase(PE), polygala-cturonase(PG) activities were also discussed. The results show that the changes of flavone percentages during postripeness include three stages: the first stage has relative stable flavone percentage (about 1.20%), the second stage has sharp decrease of flavone, the third stage has relative stable flavone percentage (about 0.70%). Abscisic acid is relatively suitable exogenous hormones, and the content of flavone is 1.19% after eight days in the range of 5.0～50.0℃, the higher ambient temperature is, the earlier flavone percentage begins to decrease sharply; the treatment immersed in lime-water is relatively suitable postripening treatment, and the flavone content is 1.02% after 11 days. In practice, flavone must be extracted within eight days after picking.