CRI Postharvest Workshops 2025

Sessions

1 Covered everything related to the broader citrus industry and some of the national and global factors that impact it. An area representative provided an overview of the 2024 packing and export season, followed by the main sponsor, who discussed some of the products and services they offer. This was followed by presentations on current market access requirements and ways to decrease packing costs and expenses by improving farm and packhouse efficiency. The Citrus Growers’ Association (CGA) was well represented, with topics like:

• current and future modifications to existing chemical active maximum residue levels (MRLs)
• newly-required pest control operator (PCO) license
• necessity of standardising carton pack codes and considerations towards the carbon footprint of an individual operation.
• logistics for the 2024 export season, including impediments to existing export corridors and reasons for lower export carton volumes; and promising rail transportation prospects.

2 Focused on how different processes and packline treatments can be improved. A strong emphasis on sanitation, from the orchard to the packhouse, marked the opening theme of this session. Pathogen spore load must be controlled and limited from the orchard to the packhouse through thorough, stringent sanitation practices.

Accurate record-keeping and management of pH and temperature for each packhouse water system and specific chemicals were discussed, to ensure effective disease control, residue loading, and risk reduction regarding decay or MRL exceedance.

Resistance development in pathogen populations can cause a devastating ripple effect. Practical methods were shared on how to prevent or manage resistance, if already detected in the packhouse.

Growers’ automatic dosing systems Valuable information was presented on how to ensure that growers’ automatic dosing systems are working as intended, and that chemical dosing is accurate. Wax bed optimisation in each component was emphasised, for sufficient wax application and effective long-term protective control of fruit.

Rind disorders and decay came under the spotlight and it was highlighted that certain types of decay are already noticeable on the trees. A discussion followed on how these can be prevented by monitoring certain climatic conditions, and through closer collaboration between the farm and packhouse.

3 The second day of the workshops started with presentations on precooling and the factors that influence this process as well as observations made in export containers.

Moisture accumulation in containers reduces the integrity of the pallet and cartons and must be kept to a minimum. Methods to improve airflow and cooling in transit were also explored. Pallet loading Simple yet essential measures were provided that ensure that pallets are loaded properly onto trucks to minimise carton and fruit damage. Issues that arose due to incorrect palletisation practices were shown and how these could be avoided by following the CRI packaging guidelines.

Citrus rind disorders Methods to determine and differentiate between the different citrus rind disorders were discussed. Currently registered fumigation (“air sanitation”) options available for packhouse use were highlighted.

4 The final session mostly consisted of topics on postharvest disease prevention and management.

Sour rot disease control The most recent research results were discussed.

Fludioxonil and azoxystrobin Through trial results, a case was made for their effectiveness and viability as imazalil substitutes for green mould control. If imazalil resistance is detected, then these actives can be recommended.

The probable cause (high humidity, old fruit, and ineffective chemical treatment) and the solution to limiting storage mould and Cladosporium on mandarins during storage and export were presented.

Packhouse chemical titrations General considerations to keep in mind were listed, to ensure accuracy of active concentration measurements and chemical top-ups.

The workshop concluded with a discussion on how the chemical drench system can be improved and maintained.

Valuable, practical information was provided to attending industry role-players, which will undoubtedly improve packhouse operations for the 2025 packing season.