Effect of autumn nitrogen on the growth and yield of winter barley in the north of Scotland

Abstract

SUMMARYIn experiments conducted between 1982/83 and 1984/85 on the winter barley cv. Igri, nitrogen, including slow release forms, applied at several growth stages in the autumn, increased vegetative growth, including vegetative tiller numbers, nitrogen content and greening, particularly in the early sown crops. By spring, these effects were less apparent and only very infrequently did autumn nitrogen applications result in an increase in fertile tiller number and yield, although the autumn nitrogen treatments had been tested in combination with several different sowing dates and spring nitrogen levels. Studies on leaf production over the winter showed that the additional leaf produced after nitrogen application was subsequently lost through leaf senescence (especially in the severe winter of 1984/85) and therefore the treated and untreated plots often recommenced growth in the spring with similar amounts of live leaf tissue. It is argued that the use of autumn nitrogen on winter cereals in the north of Scotland cannot be supported agronomically and may also be undesirable for environmental reasons.