氮磷添加对云南松苗木生长节律的影响

Effect of Nitrogen and Phosphorus Addition on Growth Rhythm of Pinus yunnanensis Seedlings

【目的】探究不同氮磷配施量对云南松苗木生长的影响,并筛选出最适合云南松苗木生长的氮磷施肥配比。【方法】以2年生云南松播种实生苗为研究对象,通过不同氮磷配比根系施肥连续追踪1.5 a,测量云南松幼苗施肥当年和施肥次年的苗高和地径生长量,并对其生长节律和异速生长进行分析。【结果】云南松苗高和地径的生长节律表现为慢—快—慢的S型生长曲线,施肥改变了云南松苗木的生长节律,可延长其苗木速生期;也改变了苗木生长轨道,可缓解云南松幼苗苗期生长缓慢的现象,促进苗木生长。中氮中磷(氮0.4 g/株,磷0.8 g/株)处理的云南松苗高生长最佳,高磷(磷1.6 g/株)处理的云南松地径长势最好。【结论】研究结果揭示了云南松幼苗在施肥当年和次年的生长节律对不同肥料用量的响应,为云南松苗期氮磷施肥量和培育优质健壮苗木提供了理论基础。

[Purpose]To explore the effects of different fertilizer amount of nitrogen(N)and phosphorus(P)on the growth of Pinus yunnanensis seedlings,and to select the most suitable N and P fertilization ratio for the growth of P.yunnanensis seedlings.[Methods]The two-year-old seedlings of P.yunnanensis were taken as the research object,and the root fertilization with different N and P ratios was continuously tracked for 1.5 years.The seedling height and ground diameter growth of P.yunnanensis seedlings in the same year and the following year after fertilization were measured,and their growth rhythm and allometry were analyzed.[Results]The seedling height and the ground diameter showed an S-shaped“slow-fast-slow”growth curve.Fertilization changed the growth rhythm of P.yunnanensis seedlings,and extended the time of the rapid growth period.It also changed the growth track of seedlings,reduced the slow growth of P.yunnanensis seedlings,and promoted the height growth of seedlings.The medium level of N and P(N 0.4 g/plant,P 0.8 g/plant)could effect-ively promote the height growth of seedlings,and the high level of P(P 1.6 g/plant)could effectively promote ground diameter growth of seedlings.[Conclusion]This study reveals the growth rhythm of P.yunnanensis seedlings in the year of fertilization and the following year in response to different fertilizer amount.And it provides theoretical research for N and P fertilization in the cultivation of high-quality P.yunnanensis seedlings.