◆  What are the forms of phosphorus in soil?

1, The inorganic phosphor: generally accounting for 50-90%of soil total phosphor, including water-soluble phosphorus, iron-aluminum boundphosphorus, closed storage phosphorus, calcium phosphate, phosphorus minerals.

2, The organic phosphorus: generally accounting for 10-50%of soil total phosphor.

◆  What are the forms of phosphorus uptake by plants?

Most of the phosphorus absorbed by plants is in the form of monovalent phosphate ion (H₂PO₄^-), mean while the small amount of two valent phosphate(HPO₄^2-) can be absorbed. Other forms of phosphorus can also be used, but the quantity is much less than that of orthophosphate.

◆  Why is the seasonal utilization rate of the phosphate fertilizerlow?

1, The ionic phosphorus is easily fixed by soil and haslittle movement distance in soil.

2, The unreasonable irrigation leading to phosphorus lossand rarely absorbed.

3, The soil environment affects the absorption of phosphorus,such as soil pH value, soil moisture, temperature, organic matter content and so on.

4, The application method of phosphate fertilizer affect the absorption, a large number of phosphate fertilizer as base fertilizer once applied to soil, excess phosphorus either fixed by soil or washed by rain.

5, The unreasonable structure of nutrient effect on phosphorus absorption.

◆  What are the typical symptoms of the phosphor deficiency in plants?

1, The plant is short and the leaves are dark green.

2, The roots are small, the secondary roots are few, and the tillers of the Gramineae crops are few.

3, The stems and leaves appear purple red stripes or spots when the phosphorus deficiency is serious.

4, The plant growth is slow, delayed maturity.