The Stability of Important Fruit Traits in Strawberry in Queensland

Information was collected on yield and fruit quality in &lsquo:Festival&rsquo:, &lsquo:Fortuna&rsquo:, &lsquo:Red Rhapsody&rsquo:, &lsquo:Fronteras&rsquo:, &lsquo:Grenada&rsquo: and &lsquo:Petaluma&rsquo: strawberry (Fragaria &times: ananassa Duch.) in southern Queensland, Australia. Marketable yield was similar in the cultivars and ranged from 352 to 416 g/plant. Fruit were smaller in &lsquo:Festival&rsquo: and &lsquo:Grenada&rsquo: (21.3 or 23.7 g), intermediate in &lsquo:Fortuna&rsquo: and &lsquo:Red Rhapsody&rsquo: (25.0 or 24.7 g), and larger in &lsquo:Fronteras&rsquo: and &lsquo:Petaluma&rsquo: (27.6 or 27.8 g). Fruit soluble solids content (SSC) was lower in &lsquo:Fronteras&rsquo:, &lsquo:Grenada&rsquo: and &lsquo:Petaluma&rsquo: (6.9% to 7.2%) than in the other cultivars (7.4% to 8.3%). Fruit titratable acidity (TA) was lower in &lsquo:Fortuna&rsquo: and &lsquo:Fronteras&rsquo: (0.55% to 0.58%) than in the other cultivars (0.63% to 0.69%). The cultivars had similar estimates of stability for fruit weight (0.74 to 1.27) using the method of Finlay and Wilkinson (1963), where a cultivar with a value of one has average stability in a group. This suggests that the cultivars behaved similarly to changes in conditions over the season. The estimates of stability for SSC were lower than one or higher than one in some cultivars (0.45 to 1.75). The estimates of stability for TA were lower than one for some cultivars (0.33 to 1.33). None of the cultivars had high values of fruit quality and stable values of fruit quality for all the three traits. &lsquo:Festival&rsquo: would be an acceptable parent in a breeding programme used to increase fruit SSC. In contrast, the other cultivars would be acceptable parents to increase fruit size. Efforts need to be made to develop cultivars with high and stable values of quality and that are suitable for production under global warming.