不同施肥配比对麦冬幼苗光合特性及干物质分配的影响

Effects of different fertilizing proportion on photosynthetic characteristics and dry matter allocation of Ophiopogon japonicus

运用L9(33)正交实验设计、采用盆栽法研究了不同浓度N(15、30和45 mmol·L-1)、P(1、3和5 mmol·L-1)和K(6、12和24 mmol·L-1)配施对麦冬〔Ophiopogon japonicus(Linn.f.)Ker-Gawl.〕幼苗光合特性和干物质分配的影响。结果表明:N肥对麦冬幼苗叶片光合特性的影响最大,其中对叶绿素a含量、净光合速率、气孔导度、胞间CO2浓度和蒸腾速率的影响均达到显著水平,以45 mmol·L-1N的促进作用最为明显;P肥对麦冬幼苗叶片光合参数均无显著影响;K肥仅对麦冬幼苗叶片类胡萝卜素含量有显著影响,以12 mmol·L-1K处理组类胡萝卜素含量为最高。N肥对麦冬幼苗地上部分和地下部分含水量的影响较大,K肥对二者的影响次之,P肥的影响较小。N肥对麦冬幼苗地上部分和地下部分干物质分配指数以及根冠比的影响较大,P肥和K肥的影响较小。综合分析结果表明:45 mmol·L-1N、1 mmol·L-1P和12 mmol·L-1K配施条件下麦冬幼苗叶片光合色素含量和植株含水量均较高,45 mmol·L-1N、3 mmol·L-1P和6 mmol·L-1K配施条件下麦冬幼苗叶片光合参数较高,30 mmol·L-1N、5 mmol·L-1P和6 mmol·L-1K配施条件下麦冬幼苗地下部分干物质分配比例较高。在麦冬的不同种植阶段可据此合理配施肥料以达到增加产量和提高品质的目的。

Using L9（3^3） orthogonal experiment design, effects of combined application of N （15, 30 and 45 mmol·L^-1）, P （1, 3 and 5 mmol·L^-1） and K （6, 12 and 24mmol·L^-1） on photosynthetic characteristics and dry matter allocation of Ophiopogon japonicus （Linn. f.） Ker-Gawl. seedling were researched by pot method. The results show that effect of N fertilizer on photosynthetic characteristics of leaf of O. japonicus seedling is the most, in which its effect on chlorophyll a content, net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate is significant as the most obvious promotion of 45 mmol·L^-1 N. Effect of P fertilizer on photosynthetic parameter of leaf is not significant. While that of K fertilizer on carotenoid content is significant with the highest carotenoid content in 12 mmol·L^-1 K treatment group. Effect of N fertilizer on water content in above- and under- ground parts of O. japonicus seedling is bigger, that of P fertilizer on them is in the second, and that of K fertilizer on them is smaller. Effect of N fertilizer on dry matter allocation index of above- and under- ground parts and root/shoot ratio is bigger, while effects of P and K fertilizers are smaller. The comprehensive analysis result shows that photosynthetic pigment content in leaf and water content in plant of O. japonicus seedling are higher in combined application condition of 43 mmol·L^-1 P and 12 mmol·L^-1 K, photosynthetic parameters in leaf are higher in combined application condition of 45 mmol·L^-1 N, 3 mmol·L^-1 P and 6 mmol·L^-1 K, and dry matter allocation ratio of under-ground part is higher in combined application condition of 30 mmol·L^-1 N, 5 mmol·L^-1 P and 6mmol·L^-1 K. Based on them, rational combined application of fertilizer at different planting stages of O. japonicus can achieve in order to the purpose of increasing production and improving quality.