Fecha de publicación: 06/01/2024 Fuente: ISHS (International Society for Horticultural Science) Post date: Saturday 6 January 2024
Author:
ISHS Secretariat

Biostimulants can improve nutrient uptake by plants, growth, productivity, fruit quality, as well as plant resilience to abiotic and biotic stresses. Among them, silicon (Si) is reported to be beneficial in mitigating stresses such as plant diseases, salinity, drought, and nutrient imbalances. For organic highbush blueberries, the ability to enhance crop resilience and produce high quality berries is essential to the success of the organic sector in international markets. Since the health-promoting compounds in fruit are often associated with secondary metabolites involved in plant defense, Si could enhance the nutritional value of berries. Indeed, it has been observed that Si increases sugar content and certain phenolic compounds. In a split-plot design over one growing season, in a greenhouse at Laval University, Quebec, we compared two different types of silicon sources: 1) organic wollastonite (58% SiO2, 23% CaO, 6% MgO) at a rate of 4 g L-1 of growing media; 2) potassium silicate (18% SiO2, 50% K) at a rate of 1.7 mM added to the irrigation water; and 3) a control receiving no Si. Eight highbush blueberry cultivars were selected for this study including early- and late-maturing cultivars, which were grown in a 10-L container with an organic peat-based growing medium provided by Berger (Saint-Modeste), which was supplemented with organic fertilizers. From an analysis of the Si leaf content, potassium silicate was absorbed in greater quantities than wollastonite. The silica content in the leaves varied from one cultivar to another: ‘Earliblue’ and ‘Liberty’ exhibited lower leaf silica content at 34 and 35%, respectively, in comparison to the average silica content of the eight cultivars included in the study. This observation implies that there is variation in the ability of highbush blueberries to absorb silicon. ‘Bluegold’ showed the highest content of Si with a total of 370 ppm. Potassium silicate had a positive effect on microbial enzymatic activity by increasing the hydrolysis of fluorescein diacetate (FDA) content of the samples when compared to plants without silica. With regard to the phenolic compounds, ‘Earliblue’ and ‘Liberty’ exhibited the lowest levels of polyphenols and anthocyanins. In contrast, ‘Bluegold’ showed the highest levels of polyphenols and anthocyanins, highlighting a correlation between Si content and phenolic compounds in highbush blueberries.
Eve-Marie Boudreau-Forgues won the ISHS Young Minds Award for the best poster presentation at the IV International Symposium on Organic Greenhouse Horticulture in Mexico in October 2023.
Eve-Marie Boudreau-Forgues, Centre de recherche et d’innovation sur les végétaux, Université Laval, 2480 Bd Hochelaga, Québec, G1V 0A6, Canada, e-mail: embof2@ulaval.ca
The article is available in Chronica HorticulturaeTags: highbush blueberriesCategories: Young Minds Award Winners