Correlation between Destructive and Non-Destructive Measurements of Highbush Blueberry (<i>Vaccinium corymbosum</i> L.) Fruit during Maturation
Tina Smrke,
Natasa Stajner,
Tjasa Cesar,
Robert Veberic,
Metka Hudina,
Jerneja Jakopic
Affiliations
Tina Smrke
Biotechnical Faculty, Department of Agronomy, Chair for Fruit Growing, Viticulture and Vegetable Growing, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
Natasa Stajner
Biotechnical Faculty, Department of Agronomy, Chair of Genetics, Biotechnology, Statistics and Plant Breeding, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
Tjasa Cesar
Biotechnical Faculty, Department of Agronomy, Chair of Genetics, Biotechnology, Statistics and Plant Breeding, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
Robert Veberic
Biotechnical Faculty, Department of Agronomy, Chair for Fruit Growing, Viticulture and Vegetable Growing, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
Metka Hudina
Biotechnical Faculty, Department of Agronomy, Chair for Fruit Growing, Viticulture and Vegetable Growing, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
Jerneja Jakopic
Biotechnical Faculty, Department of Agronomy, Chair for Fruit Growing, Viticulture and Vegetable Growing, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
A relatively new, non-destructive, method for the assessment of optimal blueberry fruit maturity directly on the plant uses a DA-meter (delta absorbance) to measure chlorophyll absorbance (IAD). Here, ‘Aurora’ fruit quality parameters (peel color, fruit firmness), chemical composition (individual sugars, organic acids and phenolics) and the relative expression of anthocyanidin synthase (ANS) genes were examined at four different maturity stages (immature, light purple, darker purple, fully ripe). All observed parameters changed significantly during ripening and sometimes exhibited high correlation with IAD values, as R2 values ranged between 0.61 and 0.97. Peel lightness (L*), chroma (C*), fruit firmness and organic acids significantly decreased during ripening, while sugars, sugar/organic acid ratio, total phenolics and relative expression of ANS significantly increased. The current study is the first to determine IAD values during different maturity stages of ‘Aurora’ fruit using a DA-meter and to evaluate their correlation with the most commonly used quality parameters of ripe fruit, fruit chemical composition and relative expression of ANS.
