title: Autotoxic ginsenosides in the rhizosphere contribute to the replant failure of Panax notoginseng.
abstract: OBJECTIVE
  Sanqi ginseng (Panax notoginseng) growth is often hampered by replant failure. In this study, we aimed to examine the role of autotoxicity in Sanqi replant failures and assess the role of ginsenosides in autotoxicity.
  
  
  METHODS
  The autotoxicities were measured using seedling emergence bioassays and root cell vigor staining. The ginsenosides in the roots, soils, and root exudates were identified with HPLC-MS.
  
  
  RESULTS
  The seedling emergence and survival rate decreased significantly with the continuous number of planting years from one to three years. The root exudates, root extracts, and extracts from consecutively cultivated soils also showed significant autotoxicity against seedling emergence and growth. Ginsenosides, including R1, Rg1, Re, Rb1, Rb3, Rg2, and Rd, were identified in the roots and consecutively cultivated soil. The ginsenosides, Rg1, Re, Rg2, and Rd, were identified in the root exudates. Furthermore, the ginsenosides, R1, Rg1, Re, Rg2, and Rd, caused autotoxicity against seedling emergence and growth and root cell vigor at a concentration of 1.0 µg/mL.
  
  
  CONCLUSIONS
  Our results demonstrated that autotoxicity results in replant failure of Sanqi ginseng. While Sanqi ginseng consecutively cultivated, some ginsenosides can accumulate in rhizosphere soils through root exudates or root decomposition, which impedes seedling emergence and growth.
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Yanguo
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Xinyue
authors.initials: X
authors.lastname: Mei
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Bingbing
authors.initials: B
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Liao
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Zhaobo
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Jianfen
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Liming
authors.initials: L
authors.lastname: Fan
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Xiahong
authors.initials: X
authors.lastname: He
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Youyong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.
authors.forename: Shusheng
authors.initials: S
authors.lastname: Zhu
mesh_terms: D036145:Ginsenosides / Q000032:analysis / Q000633:toxicity*; D053723:Panax notoginseng / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D018517:Plant Roots / Q000187:drug effects; D058441:Rhizosphere; D036226:Seedlings / Q000187:drug effects; D012987:Soil / Q000737:chemistry
chemical_list: D036145:Ginsenosides; D012987:Soil