A recent extensive review showed that the effect of Nitrogen application levels on fibre quality were rather varied and often inconsistent. As a consequence, trials were conducted in Australia in 2018 and 2019 in four locations using three popular high yielding commercial varieties common in the Australian system. Nitrogen was applied at application levels ranging from zero to excessive.
These trials concluded that in general, the application of moderate (100 to 200 kg.ha− 1) levels of N resulted in the highest yield and produced longer, more even, and stronger fibre. N application levels also negatively affected colour and lint turn out.
Nitrogen plays a major role in determining the yield, lint turn out and fibre quality. However excessive application levels over 14 to 15 kg of N for each bale produced has no economic benefit and has the potential of negatively affecting yield and fibre quality.