Oxygenated subsurface drip irrigation and organic fertilizer increase the yield and quality of <i>P. notoginseng</i> by improving soil microenvironment

Abstract Yunnan Province has the most extensive planting of Panax notoginseng (Burk) F. H. Chen, comprising more than 90% of the country's area. Many traditional cultivators employ outdated water and fertilizer management practices, which lead to inefficient utilization of these resources, a higher incidence of diseases, and a decrease in both yield and quality. Therefore, this study hopes to propose a new planting scheme with irrigation and fertilizer application to improve the yield and quality of P. notoginseng . The study focused on 5‐year‐old P. notoginseng , employing three irrigation techniques: oxygenated subsurface drip irrigation (OI), micro‐sprinkler irrigation (SI), and surface drip irrigation (DI). Additionally, four fertilizer application rates were examined: low (F 1 : 75 kg ha −1 ), medium (F 2 : 100 kg ha −1 ), medium‐high (F 3 : 125 kg ha −1 ), and high (F 4 : 150 kg ha −1 ). The results showed that oxygenated subsurface drip irrigation significantly increased the soil water content in the 0–40 cm soil layer. In addition, with the increase of organic fertilizer application, the fertilizer use efficiency (PFP) showed a downward trend. Under the interaction of different irrigation methods and fertilizer application amount, OIF 3 treatment significantly promoted root growth, enhancing root hydraulic conductivity, and the root‐shoot ratio led to a reduction in the incidence of root rot (5.72%), the highest yield (4649.70 kg ha −1 ), and the best irrigation water utilization efficiency (9.69 kg m −3 ), fertilizer utilization efficiency (1.55 kg kg −1 ) and total saponin content (12.50%). The TOPSIS model was utilized to perform an all‐encompassing assessment of P. notoginseng yield, irrigation water utilization efficiency, fertilizer utilization efficiency, and total saponin content; it was found that OIF3 treatment was optimal. This combination can create higher yield and improve the quality of P. notoginseng , which provides a new scientific planting mode and reduces the planting cost.