Evaluation of pear rootstocks for Packham’s Triumph at Jackal River Farm, Vyeboom

In South Africa, pear cultivars are planted on traditional pear rootstocks such as BP1, BP3 and BA29 showing the disadvantages of poor precocity, scion incompatibility, limited adaptability to poor soils and sensitivity to pear decline disease. The aim of this study is to evaluate new pear rootstocks under the South African environmental and growing conditions.

‘Packham’s Triumph’ trees on selected rootstocks were planted at the Jackal River Farm in the EGVV region. The following 9 rootstocks were planted: BP1, BP3, OHxF 40, OHxF 217, QC51, Pyriam, BA29/BH, QC51/BH, and QA/BH. Rootstocks were planted in a randomised block design with 10 blocks of 2 trees per plot. The experimental trees were planted at 4.5 m × 2 m (1111 trees ha¹).

Significant discrepancies regarding true-to-typeness were identified in the DNA analysis. It is very challenging, therefore, to identify real key results. Analysis showed variable performance among rootstocks. OHF217 had the greatest growth, while QC51/BH had the thickest trunks initially, though reduced over time. Yield varied, with OHF217 and QC51/BH leading in 2023. Fruit quality was similar pre-storage, but OHF217 had a significantly lower sugar-to-acid ratio post-storage.

The necessity of validating rootstock DNA prior to planting trials cannot be overstated. Accurate DNA validation is crucial to ensure that the rootstocks used in trials are true-to-type. This practice not only enhances the accuracy of performance assessments but also ensures that the data reflects genuine differences between rootstocks, rather than variations caused by misidentification. Ultimately, rigorous DNA validation supports better decision-making and advances in rootstock development and management.

Inconsistencies in rootstock DNA suggest the need for rigorous DNA validation to ensure accurate evaluation and reliable results in future trials.