Chin J Plant Ecol ›› 2008, Vol. 32 ›› Issue (5): 994-1001.DOI: 10.3773/j.issn.1005-264x.2008.05.003

• Original article • Previous Articles     Next Articles

EFFECTS OF AM FUNGI AND WATER STRESS ON DROUGHT RESISTANCE OF ARTEMISIA ORDOSICA IN DIFFERENT SOILS

HE Xue-Li(), ZHANG Huan-Shi, ZHAO Li-Li   

  1. College of Life Sciences, Hebei University, Baoding, Hebei 071002, China
  • Received:2008-01-17 Accepted:2008-04-27 Online:2008-01-17 Published:2008-09-30
  • Contact: HE Xue-Li

Abstract:

Aims Artemisia ordosica is important in vegetation succession in the Mu Us sandland of China. Little is known about the effects of AM fungi and water stress on A. ordosica under non-sterilized soil conditions. Our objective is to explore the effects of AM fungal colonization on growth and drought resistance ofA. ordosica.

Methods Glomus mosseae inoculums and the indigenous AM fungi in the rhizosphere of A. Ordosica were selected to study the effects of AM fungal colonization on growth and drought resistance ofA. ordosica. We used non-sterilized soil with two water contents: 75%-85% and 35%-45% of field moisture capacity.

Important findings Plant morphology and water content were not significantly affected by drought stress, but AM fungal colonization was seriously decreased. Leaf water retention capacity increased under water stress and the allocation of nitrogen and phosphorus to shoots was limited. The activity of superoxide dismutase (SOD) was relatively higher in the early stage of stress, and the activity of peroxidase (POD) was relatively higher in the later stage. AM fungal colonization percent and spore numbers were enhanced under the same water condition. Branch numbers and development of lateral roots, root/shoot ratio, water retention capacity, absorption of phosphorus and nutrients in roots were all improved by AM fungal colonization. Under AM fungal colonization, the contents of soluble sugar and malondialdehyde (MDA) were low, the soluble protein content did not change greatly and the activity of SOD and POD was improved. Therefore, drought resistance of A. ordosica was strengthened. There was a large discrepancy of promotion effects on A. ordosica under different soil conditions and AM fungal colonization. The effects of indigenous AM fungal colonization were better than the G. mosseae single colonization. Decline of AM infection rates might contribute to decreased plant water absorption capacity, and AM fungal colonization in the early stage of plant growth can improve the capacity for resistance to environmental drought stress at the middle-late growth stage.

Key words: arbuscular mycorrhizal fungi, water stress, drought resistance, Artemisia ordosica, soil