Tips to Keep Your Stone Fruits Safe from Rhizopus Rot
Rhizopus rot is a serious threat to your ripe apricots, peaches, nectarines, and plums. This insidious fungus, commonly caused by Rhizopus stolonifer, can wreak havoc on your postharvest produce, potentially ruining entire crates of fruit if left unchecked.
Even canned fruits are not immune to this fungus, as the pectic enzymes it produces can continue to destroy stored produce over time. However, there are ways to prevent Rhizopus from sabotaging your harvest. In this comprehensive guide, we will provide you with valuable information on how to protect your stone fruits from Rhizopus rot.
What You Will Learn
- Symptoms of Rhizopus Rot
- When Stone Fruits are the Most Susceptible
- Prevention
Symptoms of Rhizopus Rot
Identifying the early signs of Rhizopus rot is crucial to preventing further spread of the infection. The infection typically starts as a circular tan area around healthy fruit, with the skin turning tan to brown within a few hours.
A key indicator of Rhizopus infection is the ability of the skin to slip off from the flesh when slight pressure is applied. As the infection progresses, fluffy white growth of the fungus becomes visible, eventually turning black as it produces spores.
In warmer temperatures, the rot can quickly spread over the entire surface and into the flesh of the fruit.
When Stone Fruits are the Most Susceptible
Rhizopus usually infects fruit that have been bruised or injured, with ripe or near ripe fruit being particularly vulnerable. Warm, humid weather provides optimal conditions for the fungus to thrive, with temperatures between 68-77 F enabling rapid spread of the infection.
Prevention is key to minimizing the damage caused by Rhizopus rot.
Prevention
1. Orchard Sanitation
Keeping your orchard clean and free of fruit fall is crucial in preventing the spread of Rhizopus rot. Remove any fruit mummies from your trees and dispose of fallen fruit promptly.
2. Consider Preharvest Fungicides
If you have a history of Rhizopus rot in your orchard and plan to sell your harvest, consider using preharvest fungicides to protect your crops. For personal use, fungicides may not be necessary.
3. Handle Your Harvest Carefully
Minimize handling of your fruit to avoid bruising or introducing injuries that could lead to infection. Gentle handling is essential to preserving the quality of your harvest.
4. Keep Things Cool
Storing your harvest in a cool place can help prevent the onset of Rhizopus rot. The fungus cannot thrive or produce spores at temperatures below 45 F, so storing your fruit at 41 F is recommended.
Canning Your Harvest Can Be a Challenge
When canning your stone fruits, be cautious of using fruit that may have been in close proximity to infected ones. Even seemingly healthy fruit can contain enough infection to cause pectic enzymes to dissolve the cell walls over time.
While heat treatment can kill the fungus, some enzymes may persist and destroy canned fruit within months. Washing and treating your harvest with lye can help protect against this canning disorder.
Avoidance is Your Best Bet
Rhizopus rot primarily affects highly ripe apricots, peaches, nectarines, and plums. By following proper sanitation practices, handling your harvest with care, and storing fruit at cool temperatures, you can minimize the risk of infection.
If you do encounter Rhizopus rot, promptly remove infected fruit to prevent further spread of the fungus. Share your experiences with Rhizopus rot in the comments and let us know how you managed to stop the infection in its tracks.
For additional guidance on identifying and preventing diseases in stone fruits, check out the following resources:
– How to Identify, Prevent, and Treat Scab in Stone Fruits
– How to Diagnose and Prevent Phony Peach Disease
By staying proactive and implementing preventative measures, you can protect your stone fruits from Rhizopus rot and ensure a bountiful harvest.
