Effects of fertilizer N and number of years in tillage on the protein and non-protein content of feeding barley grain (cv. Nessa) and on N uptake and recovery

Abstract

The effects of six amounts (0, 17, 34, 51, 68, 85 kg N/ha) of fertilizer N, applied at sowing time, on the crude protein (N x 6-25) content of barley grain sown as the first, second and fourth or later tillage crop after grazed pasture were studied over three seasons at a total of 126 sites. In addition, non-protein N in the grain was measured at 24 sites.The overall crude protein content was 11-3% without N, increasing to 13-4% with 85 kg N/ha. The first increment of 17 kg N/ha gave the least increase in grain protein content. The year which gave the largest yields gave the lowest grain protein contents and vice versa. The mean grain protein contents without N for 1971-3 inclusive were 10-8, 11-5 and 11-8% respectively.The mean grain protein contents without N when barley was sown as the first, second and fourth or later tillage crop after pasture were 12-6, 11-5 and 10-0% respectively; the corresponding values with 85 kg N/ha were 14-4, 13-9 and 11-8%. There was a positive relationship between grain protein content and lodging, especially in barley sown as the first tillage crop after pasture, where lodging was most severe.Non-protein N was low and only accounted for 5-8 % of the total grain N content. The mean grain. N uptake with no fertilizer N applied was 82, 70 and 49 kg/ha in barley sown as the first, second and fourth or later tillage crop respectively. The apparent recovery of fertilizer N was largest in fourth or later barley. 16-2

Effects of fertilizer N and number of years in tillage on the protein content of feeding barley straw (cv. Nessa) and on N uptake and recovery

“…The effect of season on straw protein content was similar to that on grain protein in that 1971 gave the lowest protein content and 1973 the highest ( Table 1). The year with the highest straw yield, without N, had the lowest straw protein content and vice versa, as occurred with grain yield and grain N content (Gately & McAleese, 1976). Over the 126 sites straw protein content amounted to about 36 % of the grain protein content.…”

“…At present harvesting details and weather during growing there is increased interest in feeding it to dry cows seasons are given in the first paper of this series and slowly fattening animals over the winter. (Gately & McAleese, 1976). Kay (1973) stated that the crude protein content…”

“…N uptake and recovery figures of the barley straw This was determined by drying 100 g of straw for from the 126 field experiments described by 16 h at 100 °C in an oven. The total N of the straw Gately & McAleese (1976). In each the effects of dry matter was determined using a modified six amounts of fertilizer N were tested.…”

“…Henceforth, where convenient in the text, these will be designated as cropping sequences A, B and C respectively. Further details concerning these cropping sequences are given in Gately & McAleese (1976). Observations made during the 1971, 1972 and 1973 growing seasons together with rainfall and sunshine data for the 3 years are given in Gately & McAleese (1976).…”

“…Further details concerning these cropping sequences are given in Gately & McAleese (1976). Observations made during the 1971, 1972 and 1973 growing seasons together with rainfall and sunshine data for the 3 years are given in Gately & McAleese (1976). Table 1 shows the mean straw protein contents for each cropping sequence in each year, and Table 2 shows these values averaged over the 3 years and also the mean protein content over the 126 sites at each rate of N. Experimental errors were calculated by using combined variance analysis over soils (Snedecor, 1946).…”