配方施肥对文冠果光合作用的影响

研究不同施肥处理对5年生文冠果叶绿素(Chl)含量、叶片净光合速率(P_n)和新梢长的影响。结果表明，5~9月份，所有处理的Chl含量和P_n随着时间的推移均呈先升后降的趋势，在7月达到最高值；施肥能够极显著地增加新梢长度；所有处理中N₂P₁K₂处理的Chl含量、P_n和新梢长度值均为最高；随着氮、磷、钾单一施肥量的增加，Chl含量、P_n和新梢长均呈先升后降的趋势；适宜的氮(N 110 g·株^-1)、磷（P₂O5 40 g·株^-1）、钾(K₂O 80 g·株^-1)用量及其配施能够明显增加文冠果的Chl含量、P_n和新梢长。可见，适宜的施肥量可有效增强文冠果的光合能力，推迟叶绿素的降解时间，并能保持较长的高光合持续期，进而促进新生枝条的生长。

Effect of Fertilization with Formula on Photosynthesis of Xanthoceras sorbifolia

Different fertilization treatments were adopted to investigate their influences on chlorophyll (Chl) content,net photosynthetic rate (P_n) and the length of newborn branch (LNB) of 5 a born Xanthoceras sorbifolia.The results indicated that from May to September,the contents of Chl and P_n of the plants of all treatments tended to increase first and then decrease,the peak values were found in July.Fertilization could significantly promote LNB.The highest values of Chl content,P_n and LNB were found in N₂P₁K₂ treatment.Along with the increase of the amount of applying single component of N,P,and K,Chl content,P_n and LNB tended to increase first,and then decrease.The appropriate amounts of N (N 110 g per plant),P (P₂O₅ 40 g per plant),and K (K₂O 80 g per plant),or their combination could significantly improve the Chl content,P_n and LNB.It was concluded that suitable fertilizing amounts could effectively enhance the photosynthetic capacity,delay the decomposition time of chlorophyll,which can maintain a longer duration time of higher photosynthetic to promote the growth of newborn branch of X.sorbifolia.