Magnesium and Sodium in fibrophos

Magnesium improves the feed value of grass and inadequate supplies can lead to grass tetany. Regular applications of fibrophos (typically 5% MgO) maintain good levels of Magnesium in the soil thus reducing the risk of staggers.

In arable situations, Magnesium deficiencies are a problem for potatoes and sugar beet. Other crops can show symptoms but often too late to rectify. Regular applications of fibrophos will maintain adequate reserves in the soil thus reducing the risk of yield loss.

Sodium dramatically improves palatability of grass and helps to maintain healthy pastures. Cattle and sheep have been seen to favour pastures where fibrophos is applied and the feed content of the grass is enhanced.

Sodium & Magnesium uptake

Objective And Method
Levington Agriculture Ltd1998LA Project 98717
Two rates of fibrophos were applied to compare the effectiveness of the Magnesium and Sodium from fibrophos against inorganic fertiliser applied as TSP and MOP and an untreated control.
Pots were sown under heated glass with lighting. Randomised block - replicated x4.

TSP and MOP added at equal rates to the fibrophos and each was cut three times.

fibrophos increased the uptake of Sodium particularly at the second cut for the lower application rate and for both rates in the third cut.

The Sodium uptake in the grass was decreased by addition of TSP/MOP. This was more pronounced at the higher rates of application. fibrophos maintained Sodium levels in grass well above the levels of 0.15% Na at which dietary deficiency in grazing animals is a concern. The total uptake in the grass of Sodium was significantly greater when fibrophos was used.

Magnesium deficiency in the first cut where TSP/MOP was applied was significant. The overall uptake of Magnesium by the grass in this deficient soil was greatest where fibrophos was applied, with TSP/MOP resulting in a significantly lower uptake.

These effects demonstrated are important for grazing animals where Sodium and Magnesium are important constituents of their diets. fibrophos did not show the antagonism found with MOP against Sodium and Magnesium.