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Endophytic Neotyphodium lolii induced tolerance to Zn stress in Lolium perenne
Author(s) -
Monnet Fabien,
Vaillant Nathalie,
Hitmi Adnane,
Coudret Alain,
Salla Huguette
Publication year - 2001
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1034/j.1399-3054.2001.1130415.x
Subject(s) - neotyphodium , lolium perenne , photosynthesis , biology , endophyte , chlorophyll , horticulture , botany , chlorophyll a , poaceae
The effect of Zn on growth, chlorophyll a fluorescence, net photosynthetic rate, gas exchange, water content and mineral concentrations (Zn, Mn and Mg) in ryegrass infected with or free from Neotyphodium lolii was studied by addition of ZnSO 4 (0–20 m M ) to the nutrient solution. Zn induced a decrease in growth of plants at 1, 5 and 10 m M and cessation of growth at 20 m M ZnSO 4 . From 1 to 10 m M , the decrease was less pronounced in the presence of the endophytic fungus than in its absence. The growth limitation was due to an accumulation of Zn in leaves. From 8 to 15 days, the presence of the fungus in the plant led to a limitation of the Zn concentration in the leaves (24–32% lower with N. lolii than without). This restriction of Zn concentrations in leaves also had a beneficial effect on photosystem II (PSII) activities, net photosynthetic rate and internal CO 2 concentration. Particularly at 1 and 5 m M , the quantum yield of electron flow throughout PSII was greater in the presence of the fungus than in its absence and at 5 and 10 m M , the internal CO 2 concentration was maintained at a normal level. Compared with the endophyte‐free ryegrass, the symbiotic plants showed higher values of total dry weight and tiller number, indicating a tolerance to environmental Zn stress.