IN BRIEF
IN BRIEF
• INDIFFERENT responses to sulphur in spring malting barley in a mixed farming area of Scotland are probably due to farmyard manures providing sufficient sulphur for plant needs. The SAC in Aberdeen sprayed sulphur onto growing plants at various timings, but got a maximum yield response of just 6%, despite low or moderate soil S levels.
• A NEW computer model for estimating PCN numbers in fields earmarked for potatoes can predict the risk to the crop. But commercial sampling methods need improving, says the SCRIs David Trudgill. Soil type, PCN number and type, varieties grown, rotation, control methods and expected yield are fed into the model, which then forecasts how present and future crops will be affected by PCN and how the potential infestation will be affected by changes in control or planting strategy. But Dr Trudgill warns that routine sampling methods for PCN on farms are too variable to be used with the model because they can miss PCN "hot spots". *