In one experiment, on a brown colluvial clay loam derived from basalt and sandstone, wheat grown after three years of grazed lucerne and grass sheep pasture was compared with wheat grown after three years of summer (grain sorghum) or winter (grazing oats) animal cropping. In a second experiment, on a dark brown clay derived from basalt, an eight-year rotation of alternate wheat-grain sorghum was compared with four years of lucerne grown for hay followed by sorghum, wheat, oats, wheat. Wheat yields were increased by growing lucerne on the more fertile soil which had good moisture-holding capacity; lucerne did not increase wheat yields on the less fertile soil. Grain-protein content increased where wheat followed lucerne, particularly on the less fertile soil; flour quality also improved.

The effects of different concentrations of urea (1 to 12%) sprayed at heading and blooming and after blooming on the components of yield, yield, crude and true protein, gluten, Ca, P, and niacin content of wheat, were studied over 3 years. Foliar application of urea caused an increase in the number of kernels per head and 1000-kernel weight. Concentrations beyond 3% eliminated mottling in grains altogether. Mottling was inversely related to die protein content. Concentrations from 1 to 6% increased the yield of grain irrespective of season and the yield response was linear when spray was given at heading, an increase of 52 pounds per acre (4% of that under check) having been recorded with each increase of 1% in concentration, the maximum increase being of the order 24%. Subsequent sprays were not beneficial. Urea sprays increased the proportion of grain in total dry matter produced. Spraying urea resulted in considerable increase in both crude and true protein contents, the response in protein to different concentrations being linear at all the three frequencies. Increase in total protein content was largely due to that in the true protein fraction. The range of increase in protein varied from 18 to 34%. Spraying after blooming was more efficient than at heading or at blooming for enhancing the rate of accumulation of protein in grain. Increases in protein yield per acre due to N sprays ranged from 24 to 60%. Increases in gluten followed the pattern of protein and were of the order of 53 to 70%. Gluten constituted 70% of crude protein and 80% of true protein in nonsprayed wheat and 82% of crude protein and 90% of true protein in N sprayed wheat. While ash and Ca contents remained unaffected P content increased on account of spraying urea. Foliar sprays of N increased the niacin content of grain.

Comparisons were made on the effect wheat straw had on the soil nitrogen and on the yield of wheat, in a wheat summer fallow system of cropping from 1931 to 1964. When the wheat straw was burned, either in the fall following the crop or in the spring before plowing, the soil nitrogen level showed a continuous downward trend over the 34-year cropping period. When the wheat straw was returned to the soil without added nitrogen in some form, no additional benefit was gained over burning the straw, either in retaining the soil nitrogen or increasing wheat yields. When some form of nitrogenous fertilizer, either as legume straw, strawy manure, or commercial fertilizer was added to the wheat straw before plowing, the results were improved nitrogen retention and increased wheat yields. The yields of wheat over the period studied showed a definite relationship to the total nitrogen level found in the surface foot of soil.

The disease is more severe on heavier soils and in low lying and depressed areas of plantings; it appears to be less severe in crops following a long fallow and when rotations to resistant crops have been carried out. Seed treatment appears to have no effect on yield in badly infested soils. Varieties with a relatively low incidence of deadheads include Gala, Lawrence, Gabo, Cailloux and Puglu.

None, 45, 90 and 180 lb/acre N as urea were applied at five levels of available moisture. Although growing-season rainfall was above average there was no response to N on unirrigated plots and in absence of N there was only a vegetative response to extra moisture. Grain-yield responses of 5-6 bu/ acre/cwt urea were achieved both with additional N and with additional water but the highest application rates of N and of water depressed yields. Additional water generally had a greater effect on vegetative growth than on grain yield but the effect of N was more evident in grain yield.