Counteracting the Negative Effects of Copper Limitations Through the Biostimulatory Action of a Tropical Plant Extract in Grapevine Under Pedo-Climatic Constraints

Abstract

In southern Mediterranean areas, vineyards are facing the combination of increasing air temperature, drought and frequency of extreme events (e.g., heat waves) due to climate change. Since most of the berry growth and ripening phases occur during the aridity period, such environmental constraints are responsible for limitations in yield and berry quality. Within this scenario, to achieve vineyard sustainability, renewed approaches in vineyard management have been proposed and the use of plant biostimulants seems a prominent and environmental friendly practice. The aim of this study was to test four combinations of a tropical plant extract and conventional chemicals for disease control on morpho-anatomical, physiological, biochemical and berry quality in Vitis vinifera L. subsp. vinifera “Aglianico.” In particular, we aimed to evaluate the possibility to counteract the negative effects of the reductions in copper distribution, by applying the tropical plant extract enriched with: micronutrients, enzymes involved in the activation of natural defense, aminoacids, and vitamins. The halved dose of Cu in combination with the tropical plant extract allowed maintaining a reduced vegetative vigor. In the second year of treatment, the addition of the plant extract significantly improved leaf gas exchanges and photochemistry as well as the synthesis of photosynthetic pigments. At berry level, the plant extract induced an increase in phenolics accompanied by a decrease in soluble sugars. The overall results showed that the expected differences in growth performance and productivity in vines are linked to different eco-physiological and structural properties induced by the various treatments. The tropical plant extract also primed plant defenses at the leaf and fruit levels, mainly due to modifications of some structural and biochemical traits, respectively.

Effect of biostimulants on the growth, yield and nutritional value of Capsicum annuum grown in an unheated plastic tunnel

“…The application of biostimulants and herbicides decreased the cost of cultivation measures and increased economic efficiency, compared with mechanical treatments alone. Similar results were reported by Kocira 16 for soybeans, Nowosad et al 17 for beans, Budzyński et al 18 for winter oilseed rape, Bonini et al 19 for sweet peppers and Cirillo et al 20 for grapevines.…”

Effects of NaCl and CaCl2 Salinization on Morpho-Anatomical and Physiological Traits of Potted Callistemon citrinus Plants

“…For example, the lowest percentage of phenolic compounds accumulated in CaT leaves (Figure 1c,e) could imply a lowest and slowest chemical protection to the cells in case of oxidative stress. Indeed, phenolics accumulate in plant tissue, especially at the periphery of plant organs, in order to be promptly released in case of their necessity as defence mechanisms [60], but they also have a role in protecting the membranes of chloroplasts and dissipating the excess of light, thus protecting the photo-inhibitory processes [61,62]. Moreover, at the leaf morpho-anatomical level, CaT plants presented fewer trichome and gland frequencies compared to NaT (Figure 1f,g).…”

How Leaf Vein and Stomata Traits Are Related with Photosynthetic Efficiency in Falanghina Grapevine in Different Pedoclimatic Conditions

“…At harvest (89 BBCH), the number of bunches per shoot and bunch weight were determined (weighing all bunches from the same shoots). The estimation of leaf area was performed by applying an allometric estimation model measuring the leaf lamina width in the field and applying the equations calculated based on the measurement of width and area of 20 leaves per site by means of an electronic leaf area meter (LI-3100 model, LI-COR Inc., Lincoln, NE, USA) [ 13 , 58 , 59 ].…”

“…All these morpho-physiological alterations affect both yield and berry composition (e.g., soluble solids, organic acids, polyphenols), often associated with decreasing must quality [ 11 ]. In many areas of southern Italy, grapevines are subjected to water stress when high evapotranspiration is accompanied by low precipitation [ 12 ], and it has been emphasized that strategies engaged by plants to mitigate the environmental stress must be based on a deep knowledge of plant plasticity in terms of structure/functions relationships [ 13 , 14 ].…”