The Effects On NPK Proportional Fertilization On The Flowering,Fruiting And Fat Content Of Symplocos Paniculata

Symplocos paniculata(Thunb.)Miq,a deciduous shrub or small tree from Symplocaceae family.It is a woody oil plant with notable ecological and economic importance.In this study,The wild Symplocos paniculata plants were selected as experimental material,different dosage and ratio of N,P and K fertilizer applied,the effects on growth of new branch annual,flower bud differentiation,fruit setting rate,fruit shape and fruit quality were investigated.The correlation between different fertilizing strategies and theses indexs were analyzed,And the corresponding regression equations were established.The results are as follows:1)Under the condition of barren soil with low content of N,P and K,all fertilizing strategies increased the growth of new branches.Compare to the control,the maximum annual growth incresased nearly by 40%when total fertilization amount of 1 kg,and N,P and K fertilizer amount were 0.4,0.2,0.4 kg per plant applied,respectively.Whereas total fertilization amount was over 1 kg per plant,the growth new branch slowed down.2)Different proportions of N,P and K fertilizer significantly increased the ratio of flower and leaf buds and the number of flowers per ear.The treatment C(N,P,K fertilizer amount were 0.6,0.3,0.6 kg,respectively)plants had the largest number of flower buds which over 5 times compared to the control.Whereas,treatment A(N,P,K fertilizer were 0.2,0.1,0.2 kg)plants had the largest flowers number of per panicle,which is nearly double compared to control plants.The correlation between flowers number of per panicle,the ratio of flower and leaf buds and K fertilizer amount were significantly positive.3)Different proportional fertilization had different effects on fruiting rate,fruit number per ear,fruit yield of unit canopy area,fruit hundred grain weight and fruit size.The fruiting rate of the treatment E(N,P and K fertilizer amount were 0.6,0.3,and 0.2 kg respectively)plants was high to 88.19%,which was 24.9%higher than the control plants.And the treatment A plants had the highest yield of of unit canopy area(0.35 kg/m2),followed by treatment D plants(0.34 kg/m2),which increased by 150%and 140%compared with the control plants,respectively.The fruit hundred grain weight in treatment A and B were increased by 52.7%and 45.3%,respectively.The ratio of vertical/transverse diameters of the fruits increased by 7.4%/19.5%,18.0%/22.6%,respectively.4)Reasonable N,P and K proportional fertilization significantly increased the oil content of Symplocos paniculata fruit,and had different effects on the fatty acid composition.Compared to the control plants,the oil content of the treatment B plants increased by 10.42%,and treatment A plants decreases by 8.85%.The relative content of K in fertilizer was positively correlated with the content of oleic acid,which negatively correlated with the content of stearic acid and palmitate,and significant positively correlated with the ratio of unsaturated and saturated fatty acids.The correlation between amount of N,P fertilizer and the content of linolenic acid was positive.5)Comprehensive analysis results show that the fertilization of treatment D significantly increased plant fruiting rate,yield of unit crown area,fruit oil content,and oleic acid content.Namely the ratio of N,P,K is 2:1:6,fertilizer amount is 0.5～1.0 kg per plant increased yield and oil content of Symplocos paniculata.