Postharvest is the crucial link between the orchard and the consumer. To consistently and efficiently deliver high quality, safe and nutritious fruit to domestic and export markets there are many significant challenges for postharvest to overcome.
The recently completed Hort Innovation ‘Citrus Postharvest Science Program’ (CT15010) addressed these major challenges by focusing on two key components; (1) postharvest decay control, (2) managing fruit quality through the supply chain and postharvest treatments to reduce MRLs.
The aim of the research-based program was controlling postharvest decay and maintaining fruit quality through the supply chain where MRLs are not a barrier to market access.
Managing Postharvest Decay. The results of the Project showed there are significant opportunities for the effective use of new postharvest fungicides and new alternative methods for the control of postharvest decay (green and blue mould).
New fungicide chemistries and new formulations were assessed and showed significant potential for the control postharvest decay (see articles in Australian Citrus News Spring 2017, Winter 2019, Summer 2019/20). The results also showed there may be opportunities for the postharvest control of anthracnose, which can contribute to significant out-turn problems in wetter growing regions, such as Queensland.
The results of two seasons of packinghouse surveys of postharvest fungicide technical resistance showed there could be significant issues with poor postharvest sanitation and the development of technical resistance to common postharvest fungicides.
Extension articles in Australian Citrus News (Summer 2017/18, Summer 2018/19) and presentations at the Technical Forum in Adelaide and numerous regional forums / meetings were given to highlight this issue and provide recommendations for effective management.
Improving Fruit Quality. While decay is the primary cause of postharvest losses, it can be successfully managed with good postharvest practices and fungicides.
However, there are a range of other fruit quality issues which impact the ability to successfully market fruit into both domestic and export markets. These include; (1) chilling injury, (2) development of off-flavours, (3) and adoption of new technologies to improve fruit quality management during storage.
These issues were addressed with a series of postharvest storage trials. Results showed that reduced chilling injury could be achieved through greater understanding of relevant preharvest factors and the application of postharvest treatments (Australian Citrus News, Winter 2019 ).
These insights need more research to assess their efficacies over different growing seasons. A review of the potential postharvest quality effects of low dose irradiation as a market access treatment for export was also conducted. It showed low dose irradiation has a place in the market access toolbox, where high value export markets allow this treatment.
For the full article on Citrus Australia, please click here.