Selecting the right rootstock for your orchard is very important. A healthy root system that is compatible with your chosen variety and well suited to its environment is essential if your orchard is to be a success (see Tables 1 and 2).
Rootstocks should be selected for their:
- ability to perform under your soil and climatic conditions
- resistance to pests and diseases
- compatibility with the variety you are planting
- positive impact on fruit yield and quality.
To choose the right rootstock you need to have all the relevant information. Factors which will impact on the performance of different rootstocks in your situation include:
- soil type and structure, depth, drainage, pH and salt content
- pests and diseases
- whether it is replant or virgin soil
- climatic conditions expected, for example, extreme summer and winter temperatures (frosts etc.)
- water quality (salt and pH) and the type of irrigation system (sprinklers, drippers)
- compatibility with the variety you intend to grow.
|Rootstock||Fruit size||Rind thickness||Rind texture||Fruit maturity||Sugar content||Acid content||Juice content|
|Rootstock||Salinity tolerance||Calcium (alkalinity) tolerance||Suitability for sandy soils||Suitability for loamy soils||Suitability for poorly drained soils||Phytophthora resistance|
|Sweet orange||medium||high||average||average||poor||very low|
Prior to planting, obtain a comprehensive soil survey, including a soil profile description, of proposed orchard sites. This will help in rootstock selection and overall planning and management of the orchard.
When purchasing trees, ensure that they are free of major viroids and other diseases. Rootstock seed should come from a reliable source.
Budwood for propagation should be sourced from Auscitrus to ensure freedom from exocortis viroid (CEV) and other viroids that can affect tree health and vigour. Nurseries should be certified free of major diseases and have a good reputation for consistently producing high quality trees.