Effects of Nitrogen Nutrition on Seedling Growth and Photosynthetic Characteristics of Symplocos tanakana
To determine the optimal nitrogen fertilizer dosage for the rapid growth of Symplocos tanakana seedlings and enhance seedling cultivation efficiency,1-year-old Symplocos tanakana seedlings were used as experimental materials to set up 5 levels of ni-trogen fertilizer application experiment,CK(0 g·plant-1),N1(4.5 g·plant-1),N2(7.5 g·plant-1),N3(10.5 g·plant-1)and N4(13.5 g·plant-1).The effects of nitrogen nutrition on seedling growth,chlorophyll content,photosynthetic parameters and chlorophyll fluores-cence parameters of S.tanakana seedlings were studied.The results showed that appropriate nitrogen fertilizer application significantly promoted plant height,ground diameter,and leaf area of S.tanakana seedlings,with the highest values observed under N2 treatment,increasing by 67.49％,50.00％,and 49.95％compared to the control group.Chlorophyll content,net photosynthetic rate(Pn),and wa-ter utilization efficiency(Wue)also increased under 4 fertilization treatments,with peak values under N2 treatment showing increases of 63.6％,89.8％,and 79.9％compared to the control group.Maximum photochemical efficiency(FV/FM)under PSⅡ dark adaptation,actual photosynthetic efficiency(ΦPS Ⅱ),photochemical quenching coefficient(qP),and apparent photosynthetic electron transfer rate(ETR)of S.tanakana leaves initially increased and then decreased with nitrogen application,peaking under N2 treatment.Meanwhile,non-photochemical quenching coefficient(NPQ)decreased.In conclusion,proper nitrogen fertilizer application can enhance adapt-ability of S.tanakana to strong light,increase photosynthetic capacity,and effectively promote seedling growth.In this test,the optimal nitrogen supply was found to be 7.10-7.86 g·plant-1.
万方数据
维普
