School of Geography Science, Nanjing Normal University, Nanjing, 210023, China.
Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.
Appl Microbiol Biotechnol. 2019 Apr;103(8):3581-3595. doi: 10.1007/s00253-019-09676-4. Epub 2019 Feb 15.
Replant failure has threatened the production of Sanqi ginseng (Panax notoginseng) mainly due to the accumulation of soil-borne pathogens and allelochemicals. Reductive soil disinfestation (RSD) is an effective practice used to eliminate soil-borne pathogens; however, the potential impact of RSD on the degradation of allelochemicals and the growth of replant Sanqi ginseng seedlings remain poorly understood. In this study, RSD was conducted on a Sanqi ginseng monoculture system (SGMS) and a maize-Sanqi ginseng system (MSGS), defined as SGMS_RSD and MSGS_RSD, respectively. The aim was to investigate the impact of RSD on allelochemicals, soil microbiomes, and survival rates of replant seedlings. Both short-term maize planting and RSD treatment significantly degraded the ginsenosides in Sanqi ginseng-cultivated soils, with the degradation rate being higher in the RSD treatment. The population of Fusarium oxysporum and the relative abundance of genus Fusarium were dramatically suppressed by RSD treatment. Furthermore, the RSD treatment, but not maize planting, markedly alleviated the replant failure of Sanqi ginseng, with the seedling survival rate being 52.7-70.7% 6 months after transplanting. Interestingly, RSD followed by short-term maize planting promoted microbial activity restoration, ginsenoside degradation, and ultimately alleviated the replant failure much better than RSD treatment alone (70.7% vs. 52.7%). Collectively, these results indicate that RSD treatment could considerably reduce the obstacles and might also act as a potential agriculture regime for overcoming the replant failure of Sanqi ginseng. Additional practices, such as crop rotation, beneficial microorganism inoculation, etc. may also still be needed to ensure the long-term efficacy of seedling survival.
连作障碍严重威胁三七（Panax notoginseng）的生产，主要是由于土壤病原菌和化感物质的积累。土壤还原性消毒（RSD）是一种有效消除土壤病原菌的方法；然而，RSD 对化感物质降解和再植三七幼苗生长的潜在影响仍知之甚少。本研究在三七单作系统（SGMS）和玉米-三七系统（MSGS）中进行了 RSD 处理，分别定义为 SGMS_RSD 和 MSGS_RSD，旨在研究 RSD 对化感物质、土壤微生物组和再植幼苗存活率的影响。短期玉米种植和 RSD 处理均显著降解了三七种植土壤中的人参皂苷，RSD 处理的降解率更高。RSD 处理显著抑制了尖孢镰刀菌和镰刀菌属的种群。此外，RSD 处理而非玉米种植显著缓解了三七的连作失败，移栽后 6 个月幼苗存活率为 52.7%-70.7%。有趣的是，RSD 后短期玉米种植促进了微生物活性的恢复、人参皂苷的降解，并最终比 RSD 处理本身（70.7%对 52.7%）更好地缓解了再植失败。总之，这些结果表明 RSD 处理可以显著降低障碍，也可能成为克服三七连作失败的潜在农业措施。还需要其他措施，如轮作、有益微生物接种等，以确保幼苗长期存活率。
