Ou Xiaohong, Cui Xiuming, Zhu Duanwei, Guo Lanping, Liu Dahui, Yang Ye
Yunnan Provincial Key Laboratory of Panax notoginseng, Key Laboratory of Panax notoginseng Resources Sustainable Development and Utilization of State Administration of Traditional Chinese Medicine, Kunming Key Laboratory of Sustainable Development and Utilization of Famous-Region Drug, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China.
Resource Institute for Chinese Medicine and Ethnic Materia Medica, Guizhou University of Traditional Chinese Medicine, Guiyang, China.
Front Plant Sci. 2020 Dec 21;11:595095. doi: 10.3389/fpls.2020.595095. eCollection 2020.
Excessive nitrogen (N) application and potassium (K) supplement deficiency is a common problem in cultivation. However, synergistic effects of lowering N and increasing K application on yield and quality of have not been reported. Field experiments in two locations with different N and K combined application were conducted to study the effects on yield and quality. Then, the saponin accumulation mechanisms were explored by pot and hydroponic culture with 2- or 3-year-old seedlings. The investigation showed that 70% of cultivation fields reached abundant levels of total nitrogen (TN) but had deficient levels of total potassium (TK), which may be detrimental to balance the N/K uptake of . Moreover, the average biomass was 18.9 g, and saponin (PNS) content was 6.95%; both were influenced by the N/K values of . The field experiments indicated that compared to the conventional N and K application (N:K = 2:1), lowering N and increasing K application (N:K = 1:2) decreased root rot rate by 36.4-46.1% and increased survival rate, root biomass, and yield, as well as PNS content by 17.9-18.3, 5.7-32.9, 27.8-57.1, and 5-10%, respectively. The mechanism of lowering N and increasing K application on the PNS content improving was due to the decreasing of N/K value, which promoted photosynthesis, sugar accumulation, and the expression of saponin biosynthesis genes. Therefore, lowering N and increasing K application to the ratio of 1:2 would have great potential to improve the synergistic effect on yield and quality of cultivation.
过量施氮和钾肥补充不足是种植中的常见问题。然而，降低施氮量并增加施钾量对其产量和品质的协同效应尚未见报道。在两个地点进行了不同氮钾配施的田间试验，以研究其对产量和品质的影响。然后，采用盆栽和水培法，以2年生或3年生幼苗探讨了皂苷积累机制。调查显示，70%的种植田总氮（TN）含量达到丰富水平，但总钾（TK）含量不足，这可能不利于平衡其氮钾吸收。此外，平均生物量为18.9克，三七皂苷（PNS）含量为6.95%；两者均受三七氮钾值的影响。田间试验表明，与常规氮钾施肥（N:K = 2:1）相比，降低施氮量并增加施钾量（N:K = 1:2）可使根腐病发病率降低36.4 - 46.1%，并使成活率、根生物量、产量以及PNS含量分别提高17.9 - 18.3%、5.7 - 32.9%、27.8 - 57.1%和5 - 10%。降低施氮量并增加施钾量提高PNS含量的机制是由于氮钾值降低，从而促进了光合作用、糖分积累以及皂苷生物合成基因的表达。因此，将氮钾施用量比例降至1:2对提高三七种植的产量和品质的协同效应具有巨大潜力。
