The Enhancement Effect of Calcium Ions on Ectomycorrhizal Fungi-Mediated Drought Resistance inPinus sylvestrisvar.mongolica

This study evaluated the overall influence of ectomycorrhizal fungi (ECMF) and exogenous Ca(2+)supplementation on the growth, physiological, and metabolic traits ofPinus sylvestrisvar.mongolicaseedlings under water stress and well-watered conditions. Several analytical methodologies pertinent to mycology, biochemistry, and ecology were applied. Exogenous Ca(2+)was applied to 1-year-old mycorrhizalP. sylvestrisvar.mongolica,and the growth and physiological traits of various parts ofP. sylvestrisvar.mongolicawere assessed under water stress and well-watered conditions. The results showed that Ca(2+)has an additional effect on the growth ofP. sylvestrisvar.mongolicaECMF-inoculated under water stress. Ca(2+)and ECMF together can enhance the activity of antioxidant enzymes, such as CAT, POD, SOD, and APX in the seedlings, and resist the accumulation of reactive oxygen species (ROS) caused by water stress. An appropriate combination of Ca(2+)and ECMF can reduce the MDA content more efficiently inP. sylvestrisvar.mongolicaand alleviate the extent of cellular stress. However, whether the free proline content is related to ECMF/Ca(2+)inoculation remains to be further studied. The current findings indicate that, in the early stage of seedling development, it is feasible to apply exogenous Ca(2+)and ECMF to improve growth and drought resistance.

Automated summary

The study evaluated the combined influence of exogenous Ca(2+) supplementation and ectomycorrhizal fungi (ECMF) on the growth and physiological traits of Pinus sylvestris var. mongolica seedlings under water stress. The results showed that Ca(2+) and ECMF together can enhance antioxidant enzyme activity and reduce the accumulation of reactive oxygen species in the seedlings. However, the relationship between free proline content and ECMF/Ca(2+) inoculation requires further study.