9 February 1996

New liquid sulphur is fast-acting way to solve deficiency

A NEW liquid sulphur, said to be the fastest acting foliar S spray on the market, has been launched by micronutrient specialist Cutonic.

Cutonic SA60 is an ammonium thiosulphate solution with no elemental sulphur. Work in Germany shows the buffered stable formulation is "considerably" better absorbed by leaves than powdered or colloidal forms of the element," says technical director Alan Hughes.

As little as 2% of the sulphur in conventional sprays may be taken up directly – most is washed to the ground, converted to sulphate and soaked up via crop roots, he explains. In dry weather that process can be very slow.

By contrast the already oxidised form in the new product quickly reverts to sulphate to be taken in through the leaves, he claims.

In areas of very severe sulphur deficiency, Mr Hughes still advocates using fertilisers containing S. However these can "run out of steam" over a long growing season and may not match peak demand during critical periods of growth, such as stem elongation in cereals and oilseed rape.

Route to good growth

A fast-acting foliar feed may then be the only way to maintain good growth, he argues.

SA60 costs £1.40/litre and is said to be compatible with a wide range of crop protection products. Application rate depends on deficiency status, a 5-7litre/ha treatment being recommended for a "moderate" shortage, says the firms Nick Mason. &#42