Improving Blueberry Fruit Nutritional Quality through Physiological and Genetic Interventions: A Review of Current Research and Future Directions

Abstract

Blueberry, hailed as an antioxidant superfood, is the fruit of small shrubs in the genus Vaccinium (family Ericaceae). The fruits are a rich source of vitamins, minerals and antioxidants such as flavonoids and phenolic acids. The antioxidative and anti-inflammatory activities derived from the polyphenolic compounds, particularly from the abundantly present anthocyanin pigment, have been highlighted as the major contributing factor to the health-benefitting properties of blueberry. In recent years, blueberry cultivation under polytunnels has expanded, with plastic covers designed to offer protection of crop and fruit yield from suboptimal environmental conditions and birds. An important consideration is that the covers reduce photosynthetically active radiation (PAR) and filter out ultraviolet (UV) radiation that is critical for the fruit’s bioactive composition. Blueberry fruits grown under covers have been reported to have reduced antioxidant capacity as compared to fruits from open fields. In addition to light, abiotic stresses such as salinity, water deficit, and low temperature trigger accumulation of antioxidants. We highlight in this review how interventions such as light-emitting diodes (LEDs), photo-selective films, and exposure of plants to mild stresses, alongside developing new varieties with desired traits, could be used to optimise the nutritional quality, particularly the content of polyphenols, of blueberry grown under covers.

Polymer and photo‐selective covers on plant and fruit development: A review

“…The potential benefits of photo-selective protective covers and shade nets in terms of light regulation are neverthe-less manifold and include the creation and modification of interior microclimates affecting various growth-related parameters such as canopy temperature, relative humidity, and soil temperature and light (Bastías & Corelli-Grappadelli, 2012;Iglesias & Alegre, 2006;Kalcsits et al, 2017;Krishna et al, 2023;Narjesi et al, 2023;Pallotti et al, 2023). It is through a combination of interconnected, light-related factors that key physiological processes, such as photosynthesis, photomorphogenesis, and stomatal movement are regulated.…”

“…It is through a combination of interconnected, light-related factors that key physiological processes, such as photosynthesis, photomorphogenesis, and stomatal movement are regulated. It has been noted that even conventional "clear" polymer covers of the forms widely used in polytunnels and greenhouses and shade cloths can reduce the total radiant density radiant flux density and PAR by between 30% and 40% (Krishna et al, 2023). Research has also shown that even relatively low-level changes to light transmission can be beneficial or detrimental to plant growth.…”

“…Temperature is the final general factor that must be considered in any evaluation of photo-selective films for production horticulture. Depending on their installation and configuration, photo-selective shade covers can reduce, air temperature, root zone temperature (RZT), and leaf temperature (Kittas et al, 2006;Krishna et al, 2023;Möller et al, 2004;Pallotti et al, 2023;Salvadores & Bastías, 2023;Smith et al, 1984;Valli et al, 1965;J. Zhang et al, 2015).…”

“…Fresh produce is a primary source of dietary fiber, vitamins, minerals, and secondary metabolites (anthocyanins, flavonols, phenolic acids, and carotenoids; Krishna et al, 2023). In recent years, plant phenolics have also gained popularity for their pharmacological properties such as antiinflammatory, anticancer, antimicrobial, anti-allergic, antiviral, antithrombotic, and hepatoprotective (Del Rio et al, 2013;Zakaryan et al, 2017).…”

A Lightweight Detection Method for Blueberry Fruit Maturity Based on an Improved YOLOv5 Algorithm

“…As people pay increasing attention to their health, the demand for blueberry fruits is also rising. Consequently, the commercial cultivation areas for blueberry fruits are expanding [1].…”