Sugar Alcohols in Endophyte‐Infected Tall Fescue Under Drought

Abstract

Infection of tall fescue (Festuca arundinacea Schreb.) by a fungal endophyte (Acremonium coenophialum Morgan‐Jones & Gains) improves drought tolerance, but the mechanism is unknown. Research was conducted to determine if endophyte‐infected tall fescue subjected to drought stress accumulated sugar alcohols. An infected and uninfected clone of a ‘Kentucky 31’ tall fescue genotype was greenhouse grown in perlite at field capacity or −1.0 MPa for 7 d. Sugar alcohols and other soluble carbohydrates were identified in the leaf blades and sheath. Mannitol and arabitol were identified in sheaths of infected grasses, and arabitol accumulated in infected grasses under drought stress. Infected plants had greater concentrations of fructose and glucose in blades and higher glucose in sheaths than uninfected plants when grown under drought stress. We believe, therefore, that the higher carbohydrate accumulation in infected grasses contributes to osmotic potential and regrowth capacity of endophyte‐infected grasses.

Effect of Neotyphodium Uncinatum Endophyte on Meadow Fescue Yielding, Health Status and Ergovaline Production in Host-Plants

“…Most probably the plants infested with N. uncinatum survived the period better due to the symbiont, and thus, there was a higher yield under the conditions enhancing growth, in 2007. The main mechanisms of such an effect of the endophyte are mainly: an increase in the volume of the plant root system, root elongation, earlier and more rapid closing of stomata, accumulation and metabolism of carbohydrates and a greater content of phenolic compounds (Malinowski et al 1997;Elmi and West 1995;Richardson et al 1992). Owing to good growth conditions in 2007, E-plants regenerated and the differences between combinations E+ and E-in 2008, were smaller.…”

Metabolic Profiles ofLolium perenneAre Differentially Affected by Nitrogen Supply, Carbohydrate Content, and Fungal Endophyte Infection

“…We have previously shown that the endophytic alkaloids peramine, lolitrem B, and janthitrems were highly correlated with fungal biomass as well (Rasmussen et al, 2007). Mannitol is a very common polyol in fungi (Lewis and Smith, 1967) and has been described earlier to accumulate in endophyte-infected tall fescue (Richardson et al, 1992) and ryegrass plants (Harwood, 1954). Although mannitol has been implicated as an osmoprotectant in the resurrection plant Myrothamnus flabellifolia (Bianchi et al, 1993), a study in N. coenophialum-infected tall fescue indicates that mannitol levels are not increased by drought (Richardson et al, 1992).…”

“…Mannitol is a very common polyol in fungi (Lewis and Smith, 1967) and has been described earlier to accumulate in endophyte-infected tall fescue (Richardson et al, 1992) and ryegrass plants (Harwood, 1954). Although mannitol has been implicated as an osmoprotectant in the resurrection plant Myrothamnus flabellifolia (Bianchi et al, 1993), a study in N. coenophialum-infected tall fescue indicates that mannitol levels are not increased by drought (Richardson et al, 1992). A recent review (Solomon et al, 2007) also questions this role for mannitol and concludes that the role and requirement of mannitol seem to differ depending on the fungus.…”

Biological Control of Fusarium moniliforme in Maize

“…Experimental details for their use, laboratory manipulation, toxin analysis, and plant interaction are contained therein (8,(21)(22)(23)(24)(25)(26)(27).…”