Colonization of maize (Zea mays L.) with the arbuscular mycorrhizal fungus Glomus mosseae alleviates negative effects of Festuca pratensis and Zea mays root extracts.

摘要

Toxicity effects of aqueous root extracts of 4 plant species on the maize growth and arbuscular mycorrhizal fungal (AMF; Glomus mosseae) colonization were studied in a greenhouse experiment. The root extracts (0.15%, w/v) of 2 dicotyledons [stinging nettle (Urtica dioica L.) and red clover (Trifolium pratense L.)] and 2 monocotyledons [meadow fescue (Festuca pratensis Huds.) and maize (Zea mays L.)] were applied weekly to non-inoculated and AMF-inoculated maize plants. The root extracts of monocots (F. pratensis and Z. mays) contained 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), allelopathic to neighbouring plants, whereas it was not found in dicots root extracts. Maize root dry weight was lower in non-inoculated maize plants watered with fescue and maize root extracts, showing toxicity and autotoxicity effects, respectively, that were not observed in equally treated AMF-inoculated plants. However, watering with maize root extract resulted in decreased AMF colonization in maize roots [AMF frequency (F%) and intensity (M%)]. These results indicate the potential of AMF application in continuous monoculture of maize to alleviate autotoxicity.