Farm Table says:
What is the problem?
The aim of this trial was to examine Nitrogen Fertilizer Use Efficiency, through the effect on yield of different rates of nitrogen (N) fertilizer. Replicated trials were also carried out across other cotton growing regions by the Regional Development Officers.
What did the research involve?
The trials were conducted in Riverway Boggabri with the soil type as brown medium clay Vertosol. The average rainfall is around 194mm between September 2014 and March 2015.
What were the key findings?
The crop was planted and watered at 12.5 seeds per metre with 9.14 per metre established on 24 November. The crop experienced some early thrips damage with some very hot and dry weather which resulted in the first irrigation on 14 November. Hot and humid conditions occurred around 10 December which followed the one and only in-crop application of N on 5 December.
Pre-season soil tests showed very low N levels and post-season tests showed 78 Units N for Treatment 1, 114 Units for treatment 3 and 87 Units for Treatment 4 down to 90cm.
This crop had ideal conditions through January and February which set this crop up for good yields. Like the Bellevue, crop boll numbers were not overly high but they were a consistent size and weight throughout the plant. Soil type appeared to be quite consistent but we saw large variations in yield not only in the trial area but throughout the rest of the field with estimates putting yield at well over 14 bales per ha in places. Water timing was excellent and run times were short.