STUDY ON CHANGES OF THE FLAVONOID CONTENT AND SOME CORRELATIVE FACTORS OF THE LEAVES IN MALE PLANT OF GINKGO BILOBA

In male plant of Ginkgo biloba , with the experimental design consisting of three factors, i.e. the type and position of branch grown with leaves and the defoliation date, the single leaf area, content of dry matter, specific leaf fresh weight (SLFW), specific leaf dry weight (SLDW) and flavonoid content of the leaves picked randomly at interval of 30 days from July to November were measured and analysed for three years running. The research results indicated that the seasonal change of SLFW resembled to that of the flavonoid content, both of them had a peak in October; the content of dry matter and flavonoid in the leaf on the long shoot was significantly higher than that on the short shoot; SLFW, SLDW and single leaf area on one\|year\|old shoot were outstandingly larger than that on perennial branch; there were the significant or extremely significant differences at the content of dry matter, SLFW, SLDW and flavonoid content of the leaves among the different defoliation dates, and the content of dry matter from the leaves among the different branch types was different at each stage of growth and development.