Biodiv Sci

   

Effects of earthworm on tomato resistance under different drought levels

Jiman Li,Nan Jin,Maogang Xu,Jusong Huo,Xiaoyun Chen,Feng Hu,Manqiang Liu   

  1. Soil Ecology Laboratory, College of Resources and Environmental Sciences, Nanjing Agricultural University
  • Received:2021-11-27 Revised:2021-12-26 Online:2022-01-09 Published:2022-01-09
  • Contact: Manqiang Liu

Abstract:

Aims: Soil invertebrates may modify plant responses to drought stress. For example, some functional groups improve soil conditions via resource provision and water retention, potentially alleviating drought stress. The study was designed in order to mechanistically understand the functional roles of soil fauna in ecosystem services.  

Method: A pot experiment using tomatoes (Lycopersicon esculentum) was conducted in a greenhouse. The study adopted a complete factorial design that manipulated earthworm (Metaphire guillelmi) abundance and drought stress level.  

Results: It is showed that earthworms promote plant drought resistance under high drought stress, which significantly up-regulated gene expression (NCED, NSY, OPR, AOS and LOX) of abscisic acid and jasmonic acid biosynthesis, promoted the accumulation of abscisic acid and jasmonic acid by 43.2% and 33.6%, up-regulated transcription factor expression and increased the activities of catalase, peroxidase and superoxide dismutase by 12.9%, 8.4% and 47.3% in tomato shoot. But under low drought stress, earthworms up-regulated jasmonic acid synthesis pathway gene expression, but reduced abscisic acid content, and had no significant effect on the expression of transcription factors ABF4 and MYC2 genes and plant antioxidant capacity. 

Conclusion: Effects of earthworm on plant resistance depend on drought level. This study confirms the importance of soil invertebrates in plant drought resistance including the potential impact of earthworms on plant hormone synthesis, signal transduction and antioxidant capacity.

Key words: earthworms, global climate change, above-ground–below-ground, plant hormone, signal transduction