Growth Of Aphelandra Squarrosa As Affected By N-Form And Nutrient Solution PH

When plants accustomed to acid soil are transplanted to alkali soil, their growth will be affected by many nutrition problems. Two reasons maybe result in those problems. Firstly, the efficiency of microelements in the soil will be lowered by high pH level of the soil. Secondly, utilization of the nutrients at the rhizophere will be decreased. Which one is the dominant factor is the focus of the research. The experiment was conducted under controlled hydroponics to investigate the growth of Aphelandra squarrosa as influenced by N-Form (NO₃^- - N, NH₄⁺ - N and NH₄NO₃) , potassium level and nutrient solution pH (4.4,5.7 and 7.0). The results are as follows:The solution pH remained the same with NO₃^- as the sole N source. It fell significantly with NH₄⁺ as the sole N source. The solution pH also fell with both nitrate and ammonium (50:50), which decreased more lightly than that of NH₄⁺ solution. This maybe results from the compent of the nutrient solution or the heredity characteristic of Aphelandra squarrosa. N, K and their proper combined application could significantly increase the biomass of Aphelandra squarrosa and nutrient utilization efficiency.The leaf area of Aphelandra squarrosa and biomass were highest when NH₄⁺/NO₃^- were N source. While utilizing NH₄⁺ - N as the sole N source they were lowest. Besides, there was a significantly linear relationship between leaf area and biomass. The flowering rate of Aphelandra squarrosa was obviously increased when NH₄⁺ - N as the sole source. When solution pH was 4.4 or 5.7, the growth of plant was affected by N-form in a degree. When solution pH was 7.0, the effect of N-form on the growth of plant was not significant.