Plum tree

Prunus domestica

1. Identification and origin

Prunus domestica L. is an arboreal species of the Rosaceae family, known as European plum tree. Its exact origin is complex, probably resulting from the natural hybridisation between Prunus spinosa L. and Prunus cerasifera Ehrh.. It is widely cultivated in temperate regions of Europe, Asia and America, being one of the most important stone fruits.

2. Economic importance

The plum tree has great economic relevance due to the production of fresh, dried (prunes) and processed fruits (jams, jellies, juices). The diversity of cultivars allows staggered production and adaptation to different climatic conditions. The crop is valued for the high demand in the fresh fruit market and for the importance of the dehydration industry.

3. Botanical characterisation

Medium-sized tree, with a rounded crown and simple, ovate and serrate leaves. The flowers are white, solitary or in small groups, generally appearing before leaf budbreak. The fruit is a fleshy drupe, with skin of variable colouration (yellow, red, purple or bluish), sweet or acidic pulp and a woody stone. Reproduction is carried out by grafting onto compatible rootstocks.

4. Soil and climate requirements

It prefers temperate climates, with a need for chilling hours in winter to break dormancy. It is sensitive to late frosts during flowering. It requires deep, well-drained soils of medium texture and a pH between 6.0–7.5. It tolerates some dryness, but benefits from regular irrigation to ensure adequate sizes. Waterlogged soils favour root diseases.

5. Main pests

• Aphids (Aphididae): deformations and transmission of viruses.
• Fruit fly: Ceratitis capitata causes damage to ripe fruits.
• Oriental fruit moth: Grapholita molesta bores into shoots and fruits.
• Scale insects (Coccoidea): sap sucking and production of honeydew.
• Mites (Tetranychidae): silvering and reduction of the photosynthetic area.

6. Main diseases

• Brown rot: Monilinia fructigena and M. laxa cause rots and branch canker.
• Leaf curl: Taphrina deformans causes leaf deformations (less frequent than in the peach tree).
• Rust: Tranzschelia pruni‑spinosae causes orange pustules on the leaves.
• Root rots: Phytophthora spp. in poorly drained soils.
• Viruses: sharka (PPV – Plum pox virus) causes spots, deformations and loss of quality.

7. General crop management

It includes the use of certified grafted plants, planting in well-drained soils, formation and fruiting pruning, weed control and monitoring of pests and diseases. Regular irrigation improves the size and quality of the fruits. Sanitary management must include removal of mummified fruits and infected branches. Harvesting must be carried out at the optimum point of ripening, avoiding mechanical damage.

Bibliographic references

• EPPO Global Database – Prunus domestica.
• CABI – Crop Factsheets – Prunus domestica.
• FAO – Technical documents on stone fruits.
• Layne, D. R., & Bassi, D. (2008). The Peach: Botany, Production and Uses (includes chapters on Prunus spp.). CABI.
• Hartmann, H. T., Kester, D. E., Davies, F. T., & Geneve, R. L. (2011). Plant Propagation: Principles and Practices. Prentice Hall.
• Bassi, D. et al. (2015). Plum breeding and genetics. Acta Horticulturae.