Term
some things P can do for plants |
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Definition
-gives a rapid and vigorous start to plants -hastens maturity -stimulates blooming -aids in seed formation. |
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Term
Organic phosphates are present in soils as... |
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Definition
-phytins -phosphorylated sugars -nucleic acids -phospholipids. |
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Term
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Definition
Microorganisms mineralize soil organic matter and convert organic phosphates to inorganic phosphates that can be directly utilized by plants. |
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Term
Even soils high in organic phosphates cannot meet all the plant's needs from the mineralization of organic P alone. Why is this? |
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Definition
because of relatively low rates of mineralization and strong adsorption rates |
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Term
why sources of inorganic P have to be present or must be supplied for adequate plant nutrition |
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Definition
because of relatively low rates of mineralization and strong adsorption rates |
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Term
the inorganic forms of P that can be found in soil |
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Definition
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Term
the dominant type of P in highly acidic soils |
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Definition
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Term
the dominant type of P in very alkaline soils |
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Definition
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Term
the pH where a mix of H2PO4-1 and HPO4-2 are found in the soil solution |
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Definition
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Term
at this pH, the concentration of soluble aluminum and iron ions favors the formation of insoluble phosphates |
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Definition
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Term
Soils at this pH favor the formation of insoluble phosphates with calcium |
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Definition
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Term
at this pH range, a mixture of aluminum, iron, and calcium phosphates exists |
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Definition
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Term
pH where there's maximum availability of P to plants |
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Definition
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Term
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Definition
The process by which soluble forms of phosphorus are converted into less available forms |
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Term
The objective of this laboratory exercise |
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Definition
to demonstrate P adsorption by soils |
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