To cover (with multifunctional nets) or not to cover? The answer lies in the type of plantation

18 Jul 2023
1678

Multifunctional covers are becoming increasingly popular for sweet cherry production. Indeed, they exert several functions, with the goal of reducing the stresses to which plants are subjected during the vegetative season. Protection against phytophagous pests (such as Drosophila suzukii) is undoubtedly one of the main benefits, allowing a significant reduction in chemical interventions.

However, the protective effect against adverse weather conditions, such as strong wind and hail, should not be overlooked. At the same time, however, these covers induce changes at the microclimatic level, affecting the quality of light, temperature, and humidity in comparison to the external environment.

In this article, we present the results of a study conducted at the University of Bologna, which aimed to evaluate the reaction of plants grafted on rootstocks of different vigor to single-row “Keep-in-touch®” cover. In this study were used plants cv. Black Star grafted on Gisela 6 (less vigorous) and CAB6P (more vigorous), trained at transverse V shape with planting density of 4.5 m x 0.9 m (2470 plants/ha).

The cover led to stem water potentials with less negative values in Gisela 6, while no effect was shown on foliar water potentials. The cover, as expected, changed the light pattern, reducing the available light radiation by a quarter in Gisela 6 and by half in CAB6P. Plants grafted onto Gisela 6, which were subjected to a more moderate radiation decrease, showed no difference in the photosynthetic performance.

In contrast, plants grafted on CAB6P, translated the light reduction into a significant decrease in photosynthetic, transpiration and stomatal conductance rates. In terms of seasonal fruit growth, plants on Gisela 6 rootstock showed no difference between net and control, while for CAB6P the use of net caused significantly lower fruit development throughout the season.

This therefore negatively affected fruit quality at harvest in plants grafted on CAB6P both in terms of size and sugar content.

On the other hand, plants grafted on Gisela 6 produced fruit with similar quality levels in both thesis. These results show how much the rootstock influences the physiological response of plants to multifunctional covers. “Keep-in-touch®” cover had no negative impact on plants grafted on a less vigorous rootstock (Gisela 6) while in CAB6P (more vigorous) the cover affected water and photosynthetic relationships within the canopy.

This led to a reduction of water and photo-assimilates toward the fruit, resulting in a decrease in diameter and soluble solids content. The results of this study lead to the conclusion that management solutions must be combined taking into account the different physiological response depending on the rootstock adopted.

Nets improved the water status of the plant by limiting light radiation without causing photosynthetic losses, which made them beneficial in combination with the more dwarfing rootstock. This was not the case when more vigorous rootstock was employed.

Excessive reduction of light ration in the canopy caused lower stomatal conductance and, consequently, reduced photosynthesis; however, it also reduced the water potential of the fruit, decreasing its attraction force for water and photo-assimilates, which led to lower fruit development and quality.

Source: Fonte: Morandi, B., Manfrini, L., Venturi, M., Bortolotti, G., Boini, A., Perulli, G., Bresilla, K., Corelli Grappadelli, L. and Lugli, S. (2022). Physiological effects of multi-functional nets applied to cherry trees grafted on rootstocks with different vigor. Acta Hortic. 1346, 35-42

Melissa Venturi
University of Bologna (IT)


Cherry Times - All rights reserved

What to read next

Moretta di Vignola, a small cherry with prodigious properties

Varieties

01 Jun 2023

The cultivation of the Moretta di Vignola cherry has ancient and well-established origins in the Emilia (Italy) region. This cherry has phenolic substance contents that are absolutely comparable to those of fruits that are better known for their beneficial properties, such as ber

Effective strategies to improve calcium translocation in cherry orchard

Post-harvest​

02 Oct 2024

Calcium is not very mobile throughout the plant. The lack of transport capacity makes it difficult to reach the growing fruits. Another issue is that Calcium follows the water flow through the xylem, which means that its absorption is closely tied to transpiration capacity.

In evidenza

Wild cherry micropropagation: new CKX inhibitors boost in vitro growth

Nurseries

03 Dec 2025

Wild cherry (Prunus avium) micropropagation improves through three synthetic CKX inhibitors. The study shows increased biomass and in vitro proliferation, opening new perspectives for elite genotype cloning in reforestation and genetic conservation programs.

Chilean cherries: new strategy for China, USA and India between sport and health

Markets

03 Dec 2025

Fruits of Chile’s Cherry Committee presents a renewed global strategy for 2025, targeting China, USA, India and Korea. Key actions include retail partnerships, consumer education, winter sports marketing, and health-focused campaigns to boost cherry demand and trust.

Tag Popolari