Effects of spring nitrogen fertilizer on the Hagberg falling number of grain from breadmaking varieties of winter wheat

Hagberg falling number (HFN) is used to estimate alpha-amylase activity in wheat grain (Perten, 1964) and it is utilized by flour millers and the Intervention Agencies of the European Economic Community as a grain quality measurement for breadmaking (Anon. 1983). High nitrogen fertilizer application can lead to lodging and can decrease HFN (Brun, 1982). This may result from damp conditions around the ear encouraging germination, and therefore increasing alpha-amylase activity (Stewart, 1984). However, since nitrogen application can also delay maturity, it has been suggested that this influence could maintain high falling number (Anon. 1985). Pushman & Bingham (1976) found that increased nitrogen application decreased alpha-amylase activity, lending support to the previous suggestion, but contrasting with the results of Brun (1982). To attempt to clarify the relationship between nitrogen application and falling number a field experiment was undertaken in 1985 to compare the response of HFN and lodging in three varieties of wheat to spring nitrogen.