Detection of Infectious Tobamoviruses in Forest Soils

ABSTRACT Our objectives were to evaluate elution and bait plant methods to detect infectious tobamoviruses in forest soils in New York State. Soils were collected from two forest sites: Whiteface Mountain (WF) and Heiberg Forest (HF). The effectiveness of four buffers to elute tomato mosaic tobamovirus (ToMV) from organic and mineral fractions of WF soil amended with ToMV was tested, and virus content was assessed by enzyme-linked immunosorbent assay (ELISA). The effectiveness ofChenopodium quinoa (Willd.) bait plants to detect the virus also was tested. Both methods then were utilized to detect tobamoviruses in 11 WF and 2 HF soil samples. A phosphate buffer (100 mM, pH 7.0) eluted more ToMV from soil than the other buffers tested. Mineral soil bound more virus than organic soil. Virus recoveries from virus-amended organic and mineral soils were 3 and 10%, respectively, and the detection sensitivity was 10 to 20 ng/g of soil. Roots of bait plants grown in all virus-amended soils tested positive by ELISA, and virus concentrations averaged 10 ng/g. Both ToMV and tobacco mosaic tobamovirus (TMV) were transmitted to C. quinoa by elution from one of two HF soil samples but not from the WF soil samples. A tobamovirus was detected by bait planting in 12 of 73 (16%) root extracts representing 5 of 13 soil samples (38%). Tobamovirus-like particles were seen by transmission electron microscopy in 6 of 12 infected root extracts. Tobamoviruses occur in forest soils in New York State. Abiotic soil transmission to trees may permit localized spread and persistence of these viruses in forest ecosystems.

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Land use history determines non-native earthworm impacts on atmospheric methane consumption in forest soils, central New York State

Canadian Journal of Soil Science ◽

10.4141/cjss-2014-073 ◽

2015 ◽

Vol 95 (4) ◽

pp. 321-330 ◽

Cited By ~ 3

Author(s):

Joseph B. Yavitt

Keyword(s):

New York ◽

Land Use ◽

Forest Soils ◽

New York State ◽

Soil Disturbance ◽

Land Use History ◽

Leaf Fall ◽

Atmospheric Methane ◽

York State ◽

Central New York

Yavitt, J. B. 2015. Land use history determines non-native earthworm impacts on atmospheric methane consumption in forest soils, central New York State. Can. J. Soil Sci. 95: 321–330. I used complementary field and laboratory studies to examine the impact of two types of soil disturbance on net consumption of atmospheric methane (CH4) in forest soils near Ithaca, New York. One type of disturbance is invasion of non-native earthworms that mix soil layers, and the other is agriculture, which reduces the pit-and-mound surface topography to a flat landscape. Measurements of CH4 fluxes between soil and the atmosphere were made in autumn before seasonal leaf fall when earthworms had consumed all of the previous year's leaf fall, and revealed no impact by earthworms in the never-tilled soils. Although earthworms did lead to greater consumption of atmospheric CH4 in the post-agriculture soils, the mean consumption rate was only −0.2 mg m2 d−1. Concentrations of atmospheric CH4 in wormed soils were often greater than that in the atmosphere, suggesting that earthworms promote CH4 production. In general, earthworms decreased soil permeability to gas diffusion. Post-agriculture soils also had faster CH4 oxidation rates when incubated in the laboratory. The results taken together suggest that earthworm impacts on atmospheric CH4 consumption depend on the history of soil disturbance.

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