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Acremonium Endophyte Effects on Tall Fescue Drought Tolerance
Author(s) -
White Richard H.,
Engelke Milton C.,
Morton Sharon J.,
JohnsonCicalese Jennifer M.,
Ruemmele Bridget A.
Publication year - 1992
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1992.0011183x003200060017x
Subject(s) - festuca arundinacea , endophyte , biology , agronomy , poaceae , drought tolerance , acremonium , irrigation , neotyphodium , tiller (botany) , dry weight , sowing , lolium perenne , horticulture , botany
Tall fescue ( Festuca arundinacea Schreb.) is grown as a forage, turfgrass, and conservation grass from the Gulf Coast to Canada in the eastern USA. The presence of endophytes in grasses can confer resistance to insect pests, enhance growth, and improve tall fescue persistence under high temperature and drought stress. Most tall fescue is infected with Acremonium coenophialum Morgan‐Jones & Gams, a fungal endophyte. Our objectives were to determine the effects of endophyte infection on water relations and survival of water stressed (i.e., drought‐stressed) tall rescue under greenhouse conditions. Endophyte‐free and infected plants of three tall fescue selections were vegetatively propagated and grown together in 38‐L weighing lysimeters to allow interplant competition for available soil moisture. Irrigation water and fertilizer were applied for 12 wk after planting before irrigation water was withheld for 8 wk. Water‐relation characteristics including full‐turgor osmotic potential (ψ π100 ), water potential at zero turgot (ψ L0 ), relative water content at zero turgot (RWC 0 ), apoplastic water fraction ( β ), bulk modulus tissue elasticity (ϵ), and the turgid weight to dry weight ratio (TW/DW) were determined before and after water stress. Osmotic adjustment (Δψ π ) was also determined. Endophytein fection did not affect ψ π100 , ψ L0 , RWC0, and β either before or after water stress and did not affect Δψ π . Endophyte infection did affect ϵ and the TW/DW ratio, but this effect was not sufficient to alter ψ L0 . Total tillers, tiller survival, plant survival, and recovery weights were similar for endophyte‐free and ‐infected plants. No evidence for endophyte‐mediated drought tolerance was observed in this study. Based on this work, endophyte‐mediated drought resistance may be due to alterations in drought avoidance.