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C. S. Bledsoe - One of the best experts on this subject based on the ideXlab platform.
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Soil transfers from valley oak (Quercus lobata Nee) stands increase ectomycorrhizal diversity and alter root and shoot growth on valley oak seedlings
Mycorrhiza, 1998Co-Authors: J. T. Berman, C. S. BledsoeAbstract:Soils from valley oak ( Quercus lobata Nee) riparian areas of the Cosumnes River Nature Conservancy Preserve near Sacramento, California were added to growth medium of valley oak seedlings grown in a greenhouse or in agricultural fields at Cosumnes which probably once supported valley oak trees and are now replanted with native riparian vegetation or allowed to revegetate naturally. Agricultural field soil from the Cosumnes River Preserve was presumed to be low or lacking in ectomycorrhizal inoculum. The study was designed to (1) determine whether valley oak stand soil transfer could cause mycorrhizal infection on valley oak seedlings in an agricultural field and in a greenhouse, (2) describe ectomycorrhizal morphological types formed on valley oak seedlings, and (3) determine whether seedling growth is enhanced more by transfer of natural valley oak stand soil than agricultural field soil. In the field study, transfer of forest soil increased average ectomycorrhizal diversity (2.4 types) more than transfer of agricultural field soil (1.2 types). Valley oak seedlings were responsive to ectomycorrhizal infection in the field study. With increase in mycorrhizal infection there was an increase in shoot growth at the expense of root growth. In the greenhouse study, both percent mycorrhizal infection and mycorrhizal diversity were increased more by transfer of oak forest and Woodland Soils than agricultural field soil. Eight morphotypes occurred on seedlings in forest and Woodland Soils but only three morphotypes in agricultural soil. This result strongly suggests that the agricultural field also harbors ectomycorrhizal propagules but forest and Woodland Soils support a more abundant and diverse ectomycorrhizal flora.
J. T. Berman - One of the best experts on this subject based on the ideXlab platform.
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Soil transfers from valley oak (Quercus lobata Nee) stands increase ectomycorrhizal diversity and alter root and shoot growth on valley oak seedlings
Mycorrhiza, 1998Co-Authors: J. T. Berman, C. S. BledsoeAbstract:Soils from valley oak ( Quercus lobata Nee) riparian areas of the Cosumnes River Nature Conservancy Preserve near Sacramento, California were added to growth medium of valley oak seedlings grown in a greenhouse or in agricultural fields at Cosumnes which probably once supported valley oak trees and are now replanted with native riparian vegetation or allowed to revegetate naturally. Agricultural field soil from the Cosumnes River Preserve was presumed to be low or lacking in ectomycorrhizal inoculum. The study was designed to (1) determine whether valley oak stand soil transfer could cause mycorrhizal infection on valley oak seedlings in an agricultural field and in a greenhouse, (2) describe ectomycorrhizal morphological types formed on valley oak seedlings, and (3) determine whether seedling growth is enhanced more by transfer of natural valley oak stand soil than agricultural field soil. In the field study, transfer of forest soil increased average ectomycorrhizal diversity (2.4 types) more than transfer of agricultural field soil (1.2 types). Valley oak seedlings were responsive to ectomycorrhizal infection in the field study. With increase in mycorrhizal infection there was an increase in shoot growth at the expense of root growth. In the greenhouse study, both percent mycorrhizal infection and mycorrhizal diversity were increased more by transfer of oak forest and Woodland Soils than agricultural field soil. Eight morphotypes occurred on seedlings in forest and Woodland Soils but only three morphotypes in agricultural soil. This result strongly suggests that the agricultural field also harbors ectomycorrhizal propagules but forest and Woodland Soils support a more abundant and diverse ectomycorrhizal flora.
R.w. Caldwell - One of the best experts on this subject based on the ideXlab platform.
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Occurrence of Trichoderma species in apple orchard and Woodland Soils
Soil Biology and Biochemistry, 1991Co-Authors: D.j. Roiger, S.n. Jeffers, R.w. CaldwellAbstract:Abstract Native populations of Trichoderma spp in Soils associated with apple trees in Wisconsin were quantified and the diversity of species present was characterized. In all, 20 Soils were sampled from four geographical regions of Wisconsin: 17 from around apple trees, two from Woodlands immediately downhill from apple orchards and one from a virgin white pine forest. Trichoderma spp were enumerated on and recovered from dilution plates, containing a selective medium, at 8, 16 and 24°C. Because Trichoderma spp were considered as potential biological control agents of Phytophthora crown rot of apple trees, Soils also were assayed for Phytophthora cactorum (Lebert & Cohn) J. Schrot., the predominant causal agent of crown rot. with apple cotyledon baits. For most Soils, significantly fewer colony forming units (cfu) of Trichoderma spp developed at 8°C compared to 16 or 24°C. which had similar numbers of cfu. Populations of Trichoderma spp varied significantly among Soils at each incubation temperature and were not correlated with soil physical characteristics. For 12 of the Soils sampled, five isolates from each incubation temperature (180 isolates total) were retained and represented five species. T. hamatum (Bonord.) Bainier, T. harzianum Rifai. and T. koningii Oudem. occurred in more Soils than did T. virens (Miller et al.) Arx (= Cliocladium virons Miller et al) and T.viride Pers.: Fr. Each species was recovered from all geographical regions sampled except T. virens, which was recovered only from Soils collected in southern Wisconsin. T. viride was recovered only at 8 and 16°C, but other species were recovered at all three temperatures. P. cactorum was found in 17 of the 20 Soils. Trichoderma spp appear well adapted to Soils associated with apple trees in Wisconsin.
D.j. Roiger - One of the best experts on this subject based on the ideXlab platform.
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Occurrence of Trichoderma species in apple orchard and Woodland Soils
Soil Biology and Biochemistry, 1991Co-Authors: D.j. Roiger, S.n. Jeffers, R.w. CaldwellAbstract:Abstract Native populations of Trichoderma spp in Soils associated with apple trees in Wisconsin were quantified and the diversity of species present was characterized. In all, 20 Soils were sampled from four geographical regions of Wisconsin: 17 from around apple trees, two from Woodlands immediately downhill from apple orchards and one from a virgin white pine forest. Trichoderma spp were enumerated on and recovered from dilution plates, containing a selective medium, at 8, 16 and 24°C. Because Trichoderma spp were considered as potential biological control agents of Phytophthora crown rot of apple trees, Soils also were assayed for Phytophthora cactorum (Lebert & Cohn) J. Schrot., the predominant causal agent of crown rot. with apple cotyledon baits. For most Soils, significantly fewer colony forming units (cfu) of Trichoderma spp developed at 8°C compared to 16 or 24°C. which had similar numbers of cfu. Populations of Trichoderma spp varied significantly among Soils at each incubation temperature and were not correlated with soil physical characteristics. For 12 of the Soils sampled, five isolates from each incubation temperature (180 isolates total) were retained and represented five species. T. hamatum (Bonord.) Bainier, T. harzianum Rifai. and T. koningii Oudem. occurred in more Soils than did T. virens (Miller et al.) Arx (= Cliocladium virons Miller et al) and T.viride Pers.: Fr. Each species was recovered from all geographical regions sampled except T. virens, which was recovered only from Soils collected in southern Wisconsin. T. viride was recovered only at 8 and 16°C, but other species were recovered at all three temperatures. P. cactorum was found in 17 of the 20 Soils. Trichoderma spp appear well adapted to Soils associated with apple trees in Wisconsin.
Zucong Cai - One of the best experts on this subject based on the ideXlab platform.
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N2O production pathways relate to land use type in acidic Soils in subtropical China
Journal of Soils and Sediments, 2016Co-Authors: Yi Zhang, Jinbo Zhang, Wei Zhao, Zucong CaiAbstract:Purpose Agricultural practises impact soil properties and N transformation rate, and have a greater effect on N2O production pathways in agricultural Soils compared with natural Woodland Soils. However, whether agricultural land use affects N2O production pathways in acidic Soils in subtropical regions remains unknown.
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Agricultural land use affects nitrate production and conservation in humid subtropical Soils in China
Soil Biology and Biochemistry, 2013Co-Authors: Jinbo Zhang, Tongbin Zhu, Tianzhu Meng, Yanchen Zhang, Jiajia Yang, Wenyan Yang, Christoph Müller, Zucong CaiAbstract:Abstract To date, very few studies have been conducted to investigate the characteristics of gross nitrogen (N) transformations in subtropical agricultural Soils. In this study, 12 natural Woodland and 10 agricultural Soils were collected to investigate the effects of land use on soil gross N transformations in the humid subtropical zones in China. The results showed that gross autotrophic nitrification rates (average 0.19 mg N kg −1 d −1 ) in the Woodland Soils were significantly lower than those determined in the agricultural Soils (average 1.81 mg N kg −1 d −1 ) ( p 3 − immobilization rates (average 0.10 mg N kg −1 d −1 ) in the agricultural Soils were significantly lower than in the Woodland Soils (average 0.47 mg N kg −1 d −1 ) ( p 3 − produced could be immobilized into organic-N in the Woodland Soils, while, it accounted for only 10% in the agricultural Soils. These differences in gross N transformations resulted in the inorganic N being dominated by NH 4 + in the Woodland Soils; however, NO 3 − dominated the inorganic N in the agricultural Soils. The risk of N leaching and runoff from soil sharply increases after Woodland Soils are converted to agricultural Soils. Application of organic fertilizers with high C/N ratios to agricultural Soils in subtropical regions to increase soil organic C content and the C/N ratio is expected to improve NO 3 − immobilization capacity and reduce the risk of N leaching and runoff from soil.
