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Neotyphodium coenophialum interacts mutualistically with its host grasses. Tall fescue (Festuca arundinacea Schreb.) plants infected by the fungal endophyte, Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon and Hanlin, often perform better than non-infected plants, especially in limited resource environments. However, there is a scarcity of information about endophyte-grass ecotypes interaction in Andisols of temperate regions. Clones of three tall fescue ecotypes (Fukaura, Koiwai and Showa) either infected with N. coenophialum (E+) or noninfected (E)) were grown in Andisols (Black Andisol: naturally low content of phosphorus, high in other nutrients; Red Andisol: naturally high content of phosphorus, low in other nutrients) for 133 days in a controlled environment. Cumulative shoot dry weight, daily regrowth rates (tiller number, plant height and shoot dry matter) after clippings and nutrient uptake, transport and efficiency ratios were measured. In Black Andisol, E+ plants had significantly higher cumulative shoot dry weight as well as daily regrowth rates than E) plants, while in Red Andisol the reverse was true. Among the ecotypes studied, Showa had the highest shoot growth. Significantly higher phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) uptake as well as transport were identified in E+ vs. E) plants grown in Black Andisol. With few exceptions, values for nutrient efficiency ratios were not significantly different between E+ and E) plants grown in both soils. Significant three-way interaction (endophyte · ecotype · soil) for cumulative shoot dry weight and regrowth rate revealed that the ecotype specific regrowth responses to endophyte infection were depended on soil nutrient conditions. Vegetative growth and nutrient acquisition in tall fescue varied with ecotype and were modified by abiotic (soil fertility status) as well as biotic (endophyte infection) factors.

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Many reports suggest that tillage practices affect crop growth by altering soil properties. However, there is a paucity of information on long-term effects of tillage practices on the properties of modified Andisol in colder region. This study compared the effects of zero tillage (NT g ) with continuous fodder crop, zero tillage (NT a ) with continuous orchard, conventional tillage (CT) with sweet potato and corn (in summer), and wheat, barley, rye and colza (in winter), and puddling (P) with continuous rice on some selected physical and chemical properties of sandy clay pumice Andisol of colder climate. Mean dry bulk density was 0.92 Mg m 23 for CT, compared with 1.14 Mg m 23 for NT g , 1.16 Mg m 23 for NT a and 1.21 Mg m 23 for P. Total porosity was 63.75% for CT, compared with 55.16% for NT g , 53.72% for NT a and 52.24% for P. Highest content of organic matter (OM) was found in NT compared to other practices. On the other hand, soil pH and electrical conductivity (EC) were significantly lower under NT than other practices. The tillage had significant effects on soil hardness at different matric suction. Gaseous phase was greatest in CT soils, compared with NT a soils, and P soils. Mean solid phase was 44.84%, 45.29%, 47.46% and 36.25%, while liquid phase was 45.50%, 46.06%, 51.21% and 31.65% under NT g , NT a , P, and CT, respectively. Conventional tillage held highest moisture at 0 pF. On the other hand, puddled soil showed highest moisture retention capacities between 1.5 and 7.0 pF than zero tillage and conventional tillage. Gravitational water (GW) and gravitational capillary water (GCW) contents was highest while capillary water (CW), shrinkage water (SW) and hygroscopic water (HW) contents were lowest under CT. Gravitational drainage (GD) and non-easily available water (NEAW) were significantly lowest and easily available water (EAW), total available water (TAW) and non-available water (NAW) were significantly highest under puddling condition compared to other tillage systems. Highest content of boron (B) was found in NT compared to other practices. On the other hand, sulfur (S) and manganese (Mn) were significantly lowest under NT than other practices. Tillage practices had no significant effect on zinc (Zn) content. Compared with CT and P, the use of NT may result in soils having different soil physical and chemical properties, because the soil matrix undergoes fewer disturbances with NT.