Fruit Tree Diseases in France: Brown Rot

Quick read / the essentials on brown rot in fruit trees

Brown rot is a fungal disease that affects stone fruit and pome trees, causing significant losses by reducing fruit production and quality. Caused by fungi of the genus Monilia ( Monilia laxa, Monilia fructicola, Monilia fructigena ), it spreads rapidly in humid conditions and moderate temperatures. This disease mainly affects apricot, cherry, peach, plum, as well as apple and pear trees.

At Arboriverse, a specialist wholesale supplier of fruit plants , we know that prevention is the best way to combat brown rot. Regular pruning that promotes air circulation reduces humidity, thus limiting the conditions favorable to the growth of the fungus. Removing mummified fruit and infected branches is essential to prevent the spread of spores. Proper spacing between trees and controlled watering , without wetting the foliage, further reduce the risk of infection.

In organic farming, Bordeaux mixture is applied in late winter and early spring to limit contamination. The use of plant extracts and natural defense stimulators helps strengthen the trees' resistance. In conventional farming, specific fungicides are used during critical periods, with strict adherence to doses and pre-harvest intervals.

At Arboriverse, a specialist wholesale supplier of fruit trees , we offer varieties selected for their vigor and adaptation to local conditions. Buying cherry, apricot, peach, and apple trees from a specialist guarantees a healthier and more disease-resistant orchard.

Fruit tree brown rot: identification, prevention and control

Brown rot is a serious fungal disease that affects many fruit tree species. Caused by fungi of the genus Monilia ( Monilia laxa , Monilia fructicola , Monilia fructigena ), it causes significant losses in orchards, reducing both production and fruit quality. Its spread is favored by humid conditions and moderate temperatures. Effective management relies on prevention, elimination of sources of infection and the application of appropriate treatments.

Fruit tree species concerned

Brown rot primarily affects stone fruit trees, such as apricot, almond, cherry, peach, nectarine, and plum. Pome fruit trees such as apple, pear, and quince are also susceptible to this disease.

Monilia laxa and Monilia fructicola mainly affect stone fruits, while Monilia fructigena attacks more pome fruits. Other species related to susceptible fruit trees may also be susceptible, although specific information on these cases is still lacking.

Symptoms of the disease

Brown rot affects several organs of the tree, including flowers, branches and fruits.

On flowers, the infection causes rapid wilting and browning. They dry out and may remain attached to the tree, providing a source of infection for neighboring organs.

Cankers form on twigs and branches, often accompanied by gum discharge, especially in stone fruit trees. Young shoots turn brown, dry out, and curl. These lesions weaken the tree and can cause some branches to die if the infection is not stopped.

Brown spots appear on the fruit and gradually spread. The most characteristic symptom is the formation of gray, whitish, or ochre pads arranged in concentric circles on the surface of the fruit. Affected fruits quickly rot and become unfit for consumption. In many cases, they mummify and remain attached to the branches, providing a reservoir of spores for future infections.

Means of prevention

Prevention is essential to limit the occurrence and spread of brown rot.

Preventive cultural practices help reduce disease pressure in the orchard. Regular pruning improves air circulation and reduces humidity, thus limiting the conditions favorable to the development of the fungus. Spacing between trees must be sufficient to avoid moisture stagnation in the canopy.

Fruit and plant debris management is crucial. All mummified fruit must be removed and destroyed, whether still hanging from branches or fallen to the ground. Dead leaves and other organic debris must also be collected and disposed of.

Effective moisture control is essential. It is recommended to avoid watering foliage or fruit directly, especially during flowering and fruiting periods. Good soil drainage is essential to avoid excess moisture, which promotes spore development.

Varietal choice also plays an important role in preventing brown rot. Some fruit tree varieties are less susceptible than others and should be favored when planting.

Strict health measures must be implemented to limit the spread of the fungus. Regular monitoring of the orchard allows for early detection of the first signs of the disease. As soon as a branch or fruit shows suspicious symptoms, it must be removed and destroyed.

Orchard hygiene is essential. Pruning tools must be disinfected between each tree to prevent the fungus from spreading from one tree to another.

Insect pest management is another key element. Some insects, by damaging fruit and branches, create entry points for fungal infection. Careful control of insect populations thus helps limit the incidence of the disease.

Preventative treatments are particularly effective in reducing the risk of infection. A suitable spraying program should be implemented, particularly during periods of greatest risk, such as flowering and fruit formation.

Winter treatments help eliminate overwintering spores and reduce fungal pressure for the following season. Applying salicylic acid or organic silica solutions twice, at the beginning and end of winter, can strengthen the trees' natural defenses.

Another interesting strategy is the use of products that stimulate the trees' natural defenses. Certain plant extracts and organic formulations help trees better resist fungal infections.

Means of control and treatments

When moniliosis is established, targeted treatments must be applied to limit its progression and avoid new contamination.

In organic farming, Bordeaux mixture is an effective treatment against brown rot. Its application in late winter and at the beginning of flowering significantly reduces fungal pressure.

In conventional agriculture, the use of fungicides is sometimes necessary to protect orchards from disease. These treatments must be applied in accordance with the manufacturer's dosage and recommendations, as well as within pre-harvest intervals to ensure consumer safety.

Conditions favorable to the development of the disease

Brown rot thrives particularly well in wet weather. Prolonged periods of rain in spring and autumn encourage the spores to disperse and germinate on sensitive tree organs.

Moderate temperatures, between 15 and 25°C, are ideal for the growth of the fungus. Alternating humid days and cool nights further increases the risk of infection.

Conclusion

Brown rot is a serious disease affecting stone and pome fruit orchards. An effective prevention strategy relies on adopting good cultural practices, eliminating sources of infection, and implementing appropriate treatments.

When an infection is detected, rapid intervention is essential to prevent its spread. Careful monitoring of the orchard and careful treatment management help preserve tree health and ensure quality harvests.

By combining prevention, health measures and appropriate treatments, arborists can limit losses due to brown rot and guarantee the sustainability of their orchards.

To summarize: how to protect your fruit trees against brown rot?

Brown rot is a serious threat to orchards, causing considerable damage to flowers, branches and fruit. Its prevention relies on rigorous orchard maintenance, elimination of sources of infection and the application of appropriate treatments .

Arboriverse, a specialist wholesale supplier of fruit plants , supports producers by offering varieties that are resistant and adapted to growing constraints. Buying cherry, apricot, peach and apple trees from a specialist supplier is a guarantee for limiting disease risks and optimizing the profitability of the orchard.

Proper cultural management is essential to reduce fungal pressure. Careful pruning , allowing good air circulation, prevents stagnant moisture and slows the development of the fungus. The removal of mummified fruit and infected branches , combined with careful cleaning of the orchard, reduces the spread of spores. Balanced fertilization and controlled irrigation management, without spraying water on the foliage, strengthen the natural resistance of the trees.

Preventive treatments are a key tool for preventing the spread of disease. Bordeaux mixture applied in late winter and early spring is a proven solution in organic farming. Solutions based on organic silica or plant extracts can stimulate the trees' natural defenses. In conventional farming, the careful use of specific fungicides effectively protects orchards during critical periods.

Regular monitoring of the orchard and rapid intervention as soon as the first symptoms appear can contain brown rot and prevent excessive losses. At Arboriverse, a specialist wholesale supplier of fruit plants , we provide professionals with healthy and resistant plants , guaranteeing quality harvests. Buying cherry, apricot, peach and apple trees from a specialist is a strategic investment to ensure the sustainability and productivity of orchards.