Nutrient Dynamics And Fertilization Experiment Of Ginkgo Leaf-producing Plantation

Ginkgo biloba is a multipurpose tree species which were valuable for food and health care,medicine, timber, landscape, ecological protection and scientific research. The cultivationand utilization of Ginkgo has been a research hotspot both internal and abroad in recent years.This research describes the effect of different fertilization treatment on yield and medicinalquality of ginkgo leaves. We also carried out the DRIS nutrition diagnosis in Ginkgoleaf-producing plantation. The main conclusions are as follows:1. The effect of different fertilization treatment on yield is obvious according to “3414”fertilization experiment. All treatments were significantly differences. We establish ternaryquadratic fertlilizer response model according to “3414” fertilization experiment.Y（NPK）=60.279+0.801N-4.040N2+72.933P-105.615P2+30.353K-22.750K2+19.179NP+10.695NK-40.283PKWe determined the maximum content according to the fertlilizer effect function model. Themaximum content is(kg/hm2): N=1042.5, P=189.0, K=411.5(N: P: K=1:0.18:0.39), themaximum yield is43686kg/hm2, ratio is24.402.The best fertilizer modle for produce flavonoidis(kg/hm2):N=829.5、P=200.0、K=450.0，the maximum yield is63.906kg/hm2。The best fertilizermodle for produce terpene lactones is(kg/hm2):N=900.0、P=200.0、K=370.0，the maximum yieldis60.749kg/hm2。2. The nutrient contentration in Ginkgo Biloba leaves were increased. The N、P、K、Ca、Mg concentration in different fertilizer treatments are significantly different. The N、P、K、Ca、Mg nutrient concentrations in P5、P8、P10、P4、P12were highest among all treatments. Thelargest demand for ginkgo leaves is N, followed by K, then P in this study. The determinationorder in five kinds of nutrient element content is N>Ca>K>Mg>P.3. Seasonal changes of N、P、K、Mg in leaves is determined by its biological characteristicsand the mobility of Ginkgo biloba which is the same as mobility elements regular pattern inbroad-leaved tree.Leaf is vigorous growth in the preliminary stage and the N、P、K、Mg contentare higher than other parts of the tree. The N、P、K、Mg element concentrations decreased due tothe dilution effect of nutrient elements in the summer. The accumulation rate is lower than theirrate of accumulation of photosynthetic products. After this, N、 P、 K、Mg content raised. Ca isa kind of element which is difficult to move and use. So the Ca concentration of leaves washigher than that in early growth stage.4. The critical value diagnosis method is used to determine N、P、Ca concentration criticalvalue in Ginkgo leaves nutrition diagnosis. The critical value is: Limit:N:17.058mg/g、2.248mg/g、12.785mg/g,Caps:N:30.482mg/g、4.797mg/g、19.196mg/g. The optimum value is:N:23.770mg/g、3.522mg/g、15.990mg/g. DRIS nutrition diagnosis was established using theDRIS graphical method. The best ratio range of N、P、K nutrition concentration in Ginkgo Bilobaleaves were: N/P=6.403±0.617; N/K=1.728±0.023; K/P=3.702±0.307. We also determine the DRIS index and establish DRIS nutrition diagnosis.5. The flavonoids and lactone compounds contents is significantly different betweendifferent fertilization treatments. Flavone and lactone content increase firstly, then decrease withthe increasing of N、P、K. In the whole growth season, kaempferol, quercetin, isorhamnetin, thechange of total flavonoids content showed the trend of "decreasing-increasing"; Bilobalide,ginkgolide A, ginkgolide B, ginkgolide C, terpene lactone content showed trend of"increasing-decreasing".