Nutrient dynamics research: New banana trials in Wet Tropics

Curtis Project

Curtis Lanham, Queensland Department of Agriculture and Fisheries

A new trial examining plant-nitrogen use across banana production systems in the Wet Tropics recently commenced at South Johnstone research station and commercial farms.

This three year trial will be conducted by the Department of Agriculture and Fisheries (DAF) across a number of locations in the area and will incorporate the variability of current management practices, climate, soil and commercial factors that affect nutrient dynamics on farm.

A great deal has changed in the Australian banana industry in the last two decades, but in the same period, there has been very limited research conducted on nutrient use in banana production systems.

The RP191 – Banana Nutrient Trails will address the research gaps and uses a “hub and spoke research model” to ensure the network of trial sites gives the best results, assessing applied nitrogen rate treatments across a series of commercial farms, or spokes.

The trial at the South Johnstone DAF Research Station will act as the central hub linked to a network of commercial farm trial sites within the Innisfail-Tully region. The work at the DAF Research Station will be conducted at a higher intensity and frequency; something that would be too intrusive on a commercial farm.

The trial design allows for the accuracy of a replicated, controlled experiment, while at the same time providing greater understanding of how this specifically relates to commercial farms within the Wet Tropics.

The South Johnstone site has remained fallow for over a decade and is deficient of most plant-essential nutrients, creating a rare opportunity to test the critical value of soil phosphorus and define what levels are required to support production over time.

The trial will run accross a plant crop and minimum of two ratoons. Nitrogen application treatments across the network sites are:

South-Johnstone Research Station

• Plant crop – 100-325 kg N/ha/yr

• Ratoon crops – 200-425 kg N/ha/yr

Participating farms

• Plant crop – 250 kg N/ha/yr & growers’ rate

• Ratoon crops – 350 kg N/ha/yr & growers’ rate

In addition to the nitrogen rate trials, a study of soil nitrogen mineralisation will also be undertaken.

This will determine how much nitrogen is supplied to plants from the soil and how this changes over time.

A key outcome of the trial is to determine how applied nitrogen effects agronomics and economics and how this changes with area and management practices. The results will provide industry with vital research data to assist them in determining best nitrogen fertiliser use on-farm.

Along with assessing agronomics, the investigation will examine how nitrogen moves through production systems in plants and soil, and identify losses through deep drainage of soil water. This information will then be used to produce models to inform better nutrient use efficiency in future banana production systems.

The RP191 Banana Nutrient Trial is funded by Queensland Government through the Queensland Reef Water Quality Program. To get involved, or for more information, please contact DAF at 13 25 23.