Evaluation of exotic kiwifruit cultivars for adaptation to temperate highland conditions

Abstract:

Can lesser-known kiwifruit cultivars thrive outside their traditional growing zones in the Chilean highlands? This question drove the present research, which assessed six exotic kiwifruit cultivars — Hayward, Allison, Bruno, Monty, Abbott, and Tomuri — for their capacity to adapt to temperate highland conditions in Maule Region's elevated trial plots during two consecutive growing seasons (2022-2023). Vegetative growth indicators such as plant height, canopy spread, leaf area, and annual shoot extension were recorded at monthly intervals. Phenological benchmarks including days to first flowering, fruit set percentage, and days to harvest maturity were documented for each cultivar. Fruit quality traits — average fruit weight, total soluble solids, titratable acidity, ascorbic acid content, and flesh firmness — were measured at commercial maturity. Among the six entries, Hayward recorded the tallest plants (2.87 m) and widest canopy spread (3.14 m), while Bruno exhibited the earliest flowering (187 days after transplanting). Hayward also produced the heaviest fruits (78.3 g) with the highest TSS (14.2 °Brix) and ascorbic acid (89.4 mg 100 g⁻¹). Abbott and Tomuri showed moderate adaptation but lower fruit quality scores. The research points to Hayward and Bruno as the most promising cultivars for temperate highland expansion, offering a practical baseline for farmers and extension workers considering kiwifruit as a diversification crop.