RRRD054 Progress Updates

November 2012

Science Summary:

-   An additional banana trial at South Johnstone Research Station was planted on 13/12/2011 for this project to monitor and destructively sample banana plant growth over time to monitor leaf emergence, leaf expansion and leaf area. Plants are being destructively sampled to measure biomass growth and nitrogen accumulation.

-   Soil sampling is also taking place at the time of destructive sampling to better understand the nitrogen dynamics of the trial. To June 2012 six destructive sampling events had occurred, with three plants sampled each time. The trial has been visited on six other occasions to count and measure leaves and crop phonology (flowering), as well as regular monitoring by local DAFF staff.

-   To parametise the plant available water capacity at the trial site for APSIM modelling, two sites have been established at the trial site. One site is being ‘wet up’ to measure the ‘Drained Upper Limit’, or maximum capacity of the soil to hold water. The other site has a mature banana crop from which water has been excluded. This site will ‘dry down’ as the crop extracts soil water, and will measure the ‘Crop Lower Limit’, or the minimum water holding capacity of the soil under a banana crop.

-   A preliminary model has been developed in APSIM ‘Plant 2’. This model has been successfully validated against crop phenology from the RRRD049 trial.

Progress Update:

-   Data needs have been identified, published and grey literature reviewed, gaps identified and trials established to fill those gaps initiated.

-   The banana trial being used by RRRD049 at South Johnstone Research Station has been monitored by this project for leaf emergence, leaf expansion and leaf area through to bunch emergence (when leaf emergence ceased).

-   An additional two destructive sampling events occurred in August and October, with the August sample being taken during fruit development, and the October sample being taken at harvest. All plants in the RRRD054 trial have now been harvested, with twelve suckers remaining to provide data for the ‘first ratoon’ crop. All field data from the plant crop has been entered into a database.

-   Ongoing communication and collaboration with RRRD049.