Effects Of Nitrogen,phosphorus And Potassium Nutrition On Growth And Flowering Of Three Chrysanthemum Varieties

The aim of this study was to explore the effects of nitrogen,phosphorus and potassium nutrition on growth and flowering of chrysanthemum,and provide a scientific fertilization scheme in the cultivation of chrysanthemum.In this experiment,three chrysanthemum varieties were taken as the research objects,perlite was used as the cultivation medium for pot experiment,and nutrient solution was irrigated.The effects of nitrogen concentrations(40,120,180,240 and 350 mg/L)on the growth and flowering of‘Dong Li Qiu Xin’ under two fertilization intervals(3 d and 1 d),the effects of nitrogen concentrations(0,10,120,240 and 400 mg/L)on the growth and flowering of ‘Dong Li Jiao Fen’ in autumn and winter,and the effects of phosphorus concentrations(10,40,60,90 and 150 mg/L)and potassium concentrations(30,120,230,300 and 400 mg/L)on the growth and flowering of ‘Dong Li Xiao Tai Yang’ were studied respectively.The growth index,flowering condition and dry weight and so on of chrysanthemum were investigated and analyzed.The results showed that:(1)When the fertilization interval was 3 d,the crown diameter,first～third branches number,leaves number,main stem diameter,inflorescence number,per plant dry weight of ‘Dong Li Qiu xin’ were the largest under 240 mg/L nitrogen concentration,and the flowering period was the longest.The nitrogen concentration of 180 mg/L could meet the needs of crown growth and dry matter accumulation,and the chrysanthemum entered the full flowering stage at the earliest.The fertilization interval of 3 d,the nitrogen concentration of 180～240 mg/L,and the corresponding nitrogen application rate of 270～360mg/plant can be used as the reference of nitrogen fertilization for this variety.Higher nitrogen concentration could significantly improve the chlorophyll content of leaves.350mg/L nitrogen concentration significantly promoted the increase of nitrogen content in all organs,and40～120 mg/L nitrogen concentration significantly promoted the increase of potassium content in all organs.Nitrogen concentration had no significant effect on phosphorus content in flowers.Nitrogen uptake efficiency and partial productivity decreased with the increase of nitrogen concentration.(2)In autumn and winter,when the nitrogen concentration was 120 mg/L,the crown diameter,plant height,leaves number,main stem diameter and per plant dry weight of ‘Dong Li Jiao Fen’ were the largest in vegetative growth period,and the flowering condition was the best at harvest.The nitrogen concentration of 120 mg/L,and the corresponding nitrogen application rate of 144 mg/plant can be used as the reference of nitrogen fertilization for this variety in autumn and winter.The soluble sugar content of leaves increased significantly with nitrogen application,but the soluble protein content had no significantly difference with nitrogen application.(3)When the phosphorus concentration was 60 mg/L,the crown diameter,leaves number,branches number,inflorescence number and per plant dry weight of ‘Dong Li Xiao Tai Yang’ were the largest,and the flowering period was the longest.The phosphorus concentration of 40 mg/L could meet the dry matter accumulation,and the flowering period was the same as 60 mg/L phosphorus treatment.The phosphorus concentration of 40～60 mg/L,and the corresponding phosphorus application rate of60～90 mg/plant can be used as the reference of phosphorus fertilization for this variety.(4)When the potassium concentration was 230 mg/L,the crown diameter,leaves number,branches number,inflorescence number and per plant dry weight of ‘Dong Li Xiao Tai Yang’ were the largest,and the flowering period was the longest.The potassium concentration of 230 mg/L,and the corresponding potassium application rate of 345 mg/plant can be used as the reference of potassium fertilization for this variety.