Arbuscular mycorrhizal fungi influence growth, osmotic adjustment and photosynthesis of citrus under well-watered and water stress conditions

• Published in: Journal of plant physiology Vol. 163; no. 4; pp. 417 - 425
• Main Authors: Wu, Qiang-Sheng, Xia, Ren-Xue
• Format: Journal Article
• Language: English
• Published: Jena Elsevier GmbH 01.03.2006; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Arbuscular mycorrhizal fungi; Biological and medical sciences; Calcium - metabolism; carbohydrate content; Carbohydrate Metabolism; Citrus; Citrus - growth & development; Citrus - microbiology; Citrus - physiology; Citrus reticulata; Economic plant physiology; Fundamental and applied biological sciences. Psychology; Glomus versiforme; leaf water potential; Magnesium - metabolism; Mycorrhizae - physiology; mycorrhizal fungi; Osmosis - physiology; Osmotic adjustment; osmotic pressure; Photosynthesis; Photosynthesis - physiology; physiological response; plant biochemistry; Plant Leaves - anatomy & histology; Plant Leaves - physiology; plant physiology; plant response; Plant Roots - growth & development; Plant Roots - microbiology; Plant Roots - physiology; plant stress; Plant Transpiration - physiology; Potassium - metabolism; Proline - metabolism; seedling growth; seedlings; starch; stomatal conductance; sugar content; tangerines; Temperature; transpiration; vesicular arbuscular mycorrhizae; Water - metabolism; water content; Water relations, transpiration, stomata; Water stress; WW; Arbuscular mycorrhizal fungi; E; Lt; Ψ; AM; Water stress; Citrus; Osmotic adjustment; AMF; g s; Photosynthesis; WS; Pn; NSC; RWC; Temperature; Root; Starch; Growth; Rutaceae; Stomatal conductance; Plant leaf; Biomass; Water potential; Fungi; Transpiration; Dicotyledones; Angiospermae; Mycorrhiza; Water content; Spermatophyta; Carbohydrate; Colonization; Thallophyta
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2005.04.024

The influence of arbuscular mycorrhizal (AM) fungus Glomus versiforme on plant growth, osmotic adjustment and photosynthesis of tangerine ( Citrus tangerine) were studied in potted culture under well-watered and water stress conditions. Seven-day-old seedlings of tangerine were transferred to pots containing Glomus versiforme or non-AMF. After 97 days, half of the seedlings were subject to water stress and the rest were well-watered for 80 days. AM colonization significantly stimulated plant growth and biomass regardless of water status. The soluble sugar of leaves and roots, the soluble starch of leaves, the total non-structural carbohydrates (NSC) of leaves and roots, and the Mg 2+ of leaves were higher in AM seedlings than those in corresponding non-AM seedlings. The levels of K + and Ca 2+ in leaves and roots were higher in AM seedlings than those in non-AM seedlings, but differences were only significant under water stress conditions. Moreover, AM colonization increased the distributed proportions of soluble sugar and NSC to roots. However, the proline was lower in AM seedlings compared with that in non-AM seedlings. AM seedlings had higher leaf water potential ( Ψ), transpiration rates ( E), photosynthetic rates (Pn), stomatal conductance ( g s ), relative water content (RWC), and lower leaf temperature (Lt) than corresponding non-AM seedlings. This research also suggested that AM colonization improved the osmotic adjustment originating not from proline but from NSC, K +, Ca 2+ and Mg 2+, resulting in the enhancement of drought tolerance.