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The influence of sugar foam amendment on the moisture-retention properties of three profiles of an acidic vineyard soil in Retuerta del Bullaque (Ciudad Real, Spain) has been studied. The values obtained for the surface horizons of modified soils and the original soil (under natural vegetation) were compared, as were those for the surface and subsurface horizons of the liming profiles. The water-retention curves (drying curve) were determined in triplicate on the sieved soil with Richards plates and the field capacity (FC), permanent wilting point (PWP), and available water-retention capacity (AWRC) were calculated. In the original soil FC, PWP, and AWRC values were greater than the average values for the amended soils (36.5 percent, 15.1 percent, and 21.5 percent versus 23.5 percent, 10.35 percent, and 13.1 percent, respectively). Comparison of the surface horizons and the subsurface horizons of the three profiles showed that the values for the AWRC were greater in the former (13.1 percent, 12.5 percent, and 14 percent for P1, P2, and P3, respectively) than in the latter (11.9 percent, 9 percent, and 8.6 percent for P1, P2, and P3, respectively), although FC and PWP were lower in A horizons than in B horizons. [ABSTRACT FROM AUTHOR]

•Effect of no-tillage (NT) and liming on a rainfed oat-vetch mixture was evaluated. •Mycorrhizal root colonization of both crops was higher under NT and in limed plots. •Oat N content was increased by liming and NT while N vetch content only by liming. •Plant P contents were unaffected and the N:P ratio was increased by liming and NT. •Crop yields were increased by NT and liming showing a positive interaction. The combination of no-tillage (NT) and liming has been proposed as feasible means to restore degraded acid soils. However, the synergistic effect of both practices on nutrient acquisition by crops has not been addressed. Similarly, the simultaneous impact on arbuscular mycorrhizal fungi (AMF) is under-investigated despite its essential role in plant growth and nutrient uptake, especially under stress conditions. We evaluated the plant growth, nutrient acquisition and mycorrhizal root colonization at three stages during a growing season along with soil properties of a rainfed oat (Avena sativa L.) and vetch (Vicia sativa L.) mixture under Mediterranean condition. The experiment was located in south-west Spain where tillage type (no tillage: NT and traditional tillage: TT) and lime application were evaluated in a full factorial design. Liming raised soil pH, increased soil calcium and magnesium availability and stimulated the microbial activity while NT enhanced soil carbon content. Both practices improved oat biomass production (40 times at biomass harvest) and root colonization of both crops (80 % and 60 % higher respect to TT without liming in oat and vetch, respectively). Liming enhanced vetch biomass production (20 times at harvest) and foliar N content, while NT increased foliar N content of oat. Plant phosphorous (P) contents were unaffected by the treatments. The high N:P of both crops indicates P limitation despite of the high soil P content. The P limitation together with the increased N supply could lead to strengthening of mutualism between plants and AMF, where P acquisition through AMF is stimulated in order to take advantage of the "luxury" N supply provided by NT and liming. Thus, both practices together increase nutrient use efficiency by stimulating crop-microbe interactions. [ABSTRACT FROM AUTHOR]