配方施肥对刨花润楠幼苗生长和光合生理的影响

采用正交试验设计，研究不同配比施肥对刨花润楠幼苗生长和光合生理的影响。对生长及光合生理指标测定表明，不同处理的刨花润楠的地径生长量比对照（CK）提高9.14%~123.60%；株高生长量比CK提高10.14%~86.12%；生物量比CK提高0.85%~74.87%。对刨花润楠光合指标影响是叶绿素总含量比CK增加12.58%~67.65%；净光合速率（P_n）值比CK提高6.0%~294.33%；蒸腾速率(T_r)值比CK提高27.80%~280.51%；气孔导度(G_s)值比CK提高0~300.00%；施肥对胞间CO₂浓度(C_i)值的影响呈现一定的波动，CK的胞间CO₂浓度(C_i)值最高。氮肥是影响株高、生物量生长、总叶绿素含量以及光合生理指标的重要因子，钾肥是影响地径生长的重要因子。综合评价表明，施肥量为N:240 mg·株^-1、P:36 mg·株^-1、K:162 mg·株^-1 (按纯N、P、K含量计算)对刨花润楠的生长和生理指标的促进作用最显著。

Effects of Formulated Fertilization on the Growth and Photosynthetic Physiological Properties of Machilus pauhoi Seedlings

The fertilization experiment was carried out by using an L₉(3⁴) orthogonal design and regression analysis to examine the effects of different combined fertilization of nitrogen (N), phosphorus (P) and potassium (K) on the growth and physiological of the Machilus pauhoi seedlings. The results showed that the ground diameter, height growth, biomass of the potted seedlings increased by 9.14%-123.60%, 10.14%-86.12%, and 0.85%-74.87%, respectively than those of the control. The total chlorophyll content, net photosynthetic rate (P_n), transpiration rate (T_r), and stomatal conductance (G_s) increased by 12.58%-67.65%, 6.00%-294.33%, 27.80%-280.51% and 0-300.00% than the control. Intercellular CO₂ concentration (C_i) presented some fluctuation. Maximum value of C_i was found in the control seedlings. Analysis showed that the growth indices of height, biomass, total chlorophyll content and the photosynthetic physiological indices were decided by the content of nitrogen, and the ground diameter was decided by the content of potassium. The comprehensive evaluation showed that the fertilization treatment No. 2 (N₁P₂K₂) could significantly promote the growth and photosynthetic physiological indices of M. pauhoi, and recommended application rates of N, P and K were 240, 36 mg·plant^-1 and 162 mg·plant^-1, respectively.