Suggested Se forms: sodium selenite or sodium selenate.
Open-label, phase I dose-escalation study of sodium selenate, a novel activator of PP2A, in patients with castration-resistant prostate cancer.
From early 1980s, sodium selenate at rates up to 10 g Se/ha has been recommended instead of sodium selenite, because at one-fifth of the rate of sodium selenite, sodium selenate will raise pasture Se concentrations to the same level (Grant 1965).
Several types of sodium selenate fertiliser have been available for farmers to choose from.
Unitech Agsel contains Se in the form of sodium selenate in a safe polymer coating (Morton et al.
After application of sodium selenate granules in the form of Unitech Agsel to the pure ryegrass sward in the glasshouse trays, the trend observed in decreasing herbage Se concentrations with time (taking 7 months to return to background concentrations, Table 3) is similar to the trends observed in a series of field trials conducted in New Zealand by Watkinson (1983) on pasture topdressed with sodium selenate in superphosphate or in prills.
1994) reported that a single application of sodium selenate fertiliser at 10 g Se/ha maintained adequate Se status (>0.
This method of comparison of fertiliser efficiencies is similar to the method used by Whelan and Barrow (1994) in comparing the efficiencies of sodium selenate and barium selenate in a subterranean clover based pasture field trial in Western Australia (Fig.
Therefore, all Se in this fertiliser is readily available to the plants from the time of application, whereas Se in Selcote Ultra, which consists of 50% sodium selenate and 50% barium selenate and has only 38% of the total Se soluble in water, acted as a slow-release Se fertiliser.
6 for Selcote Ultra is similar to that for Unitech Agsel, suggesting that the plants were utilising Se mainly from the sodium selenate component in Selcote Ultra.
The cumulative Se recoveries in herbage are much higher than the value of 15% reported by Watkinson and Dixon (1979) in a pot trial with ryegrass fertilised with sodium selenate solution at a rate of 10 g Se/ha, 11 weeks after Se application.