M. G. Mason

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DAFWA Collections

Grains and field crops


Rates of Nitrogen on Wheat, Oats and Barley - Soil Test. In this, the third year of this programme, 44 sites were selected and soil sampled during February - March. Thirty seven of these trials consisted of four replications on wheat only and the other seven consisted of three replications on wheat, oats and barley. All reps were soil sampled separately. In each rep. of the 37 trials, 20 samples were taken to 10 cm depth with pogo stick samplers. In the. other seven trials 50 samples per rep. were taken. In addition, from three holes at random across each of the 37 trials, bulk samples were obtained from the 0-15, 15-30 and 30-45 cm. soil intervals. In the other seven trials four random holes were put down. These samples were air dried (if not already dry) and sieved to remove the > 2mm. fraction (gravel). - 77A1, 77A2, 77AL2, 77B2, 77BA1, 77BA2, 77BRI, 77C1, 77C2, 77DE4, 77E3, 77ES1, 77ES3, 77ES4, 77ES5, 77DE3, 77GE1, 77GE2, 77GE3, 77JE2, 77JE28, 77KA1, 77KA2, 77LG1, 77LG2, 77ME1, 77M2, 77ME1, 77ME2, 77ME3, 77ME4, 77MO3, 77MO4, 77MO5, 77MT3, 77N4, 77N5, 77N6, 77NA1, 77NA2, 77NA3, 77NA4, 77NO1, 77NO2, 77SG1, 77SG2, 77TS4, 77TS5, 77WH4, 77WH5. Discussion The results show no effect of Phostoxin treatment alone on germination. In fact, if anything, the treated seed germinated a little faster than the untreated seed. The combination of Phostoxin treatment and Agras at the two higher rates has resulted in plant emergence problems. The difference between treated and untreated seed was less at 200kg Agras/ha than with 100kg/ha. This is difficult to explain. However, final plant counts, after plant deaths, showed a similar difference between the two seed sources. The greater effect on plant numbers with topdressing Agras and untreated seed is unexpected and not the normal result. This could be explained by the fact that the seeds were just germinating by the time of the first watering and the fertiliser would have been washed into the germinating seed zone. With the treated seed there was little effect in this case and these seeds may have germinated a little earlier than the untreated seed and therefore been less affected. The fact that sulphate of Ammonia did not produce the same effect as Agras, which is made from sulphate of ammonia and mono-ammonium phosphate, suggests that the harmful effect is associated with the MAP fraction of Agras. Several more pot trials will be carried out to further investigate this aspect.

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Western Australia