Masstock potato specialist Peter Jones said use of Kicka, applied close to the planted seed, could enable growers on mediumto low-fertility soils to cut nitrogen rates by 100kg/ha with no consequential loss of yield.
He said: "It could be significant for farmers complying with NVZ and RB209 rulings and could bring environmental benefits from a reduction in nitrogen use. It will improve potato crop gross margins, too."
Jones said using 150kg of nitrogen per hectare resulted in crops with extra marketable yields of more than 10.1 tonnes/ha. "With ammonium nitrate at £190/tonne, Estima at £100/tonne and Kicka at £65/hectare, the margin over input costs was a creditable £990 - a definite plus."
Replicated trials compared the use of Kicka with three different nitrogen levels. "In Cheshire, Kicka applied with the lowest nitrogen level resulted in 53% more marketable yield from 37% more tubers. The following year, although the response was less dramatic, the plots with 150 kg/ha nitrogen and Kicka gave over 23% more marketable yield than those without. This treatment had 11% more tuber numbers."