Chitosan and Laminarin as Alternatives to Copper for Plasmopara viticola Control: Effect on Grape Amino Acid

Abstract

Copper fungicide use is limited by the European regulation; therefore, new strategies have been developed to prevent grapevine downy mildew (GDM). However, there is poor information about their effects on grape amino acid composition. This field trial aimed to evaluate the effect on grape amino acid composition of chitosan and of a mixture of laminarin and Saccharomyces extracts (LamE), applied in different strategies with copper hydroxide. The results showed that all the treatments applied to grapevines decreased the concentration of several amino acids. Moreover, treatments that have mostly decreased these compounds are those with copper hydroxide, especially when applied individually. LamE applied individually or alternately with copper hydroxide had the least negative effect on grape amino acid content. These results provide further information about the negative effects of copper on grape quality, which can be reduced when it is used in strategy with LamE or chitosan in GDM control.

A review of the use of biostimulants in the vineyard for improved grape and wine quality: effects on prevention of grapevine diseases

“…Vitalini et al 47 Laminarin Grape Decreased free amino acid contents Garde-Cerdán et al 22 Methyl jasmonate Grape Increased His, Ser, Trp, Phe, Tyr, Asn, Met and Lys contents Garde-Cerdán et al 48…”

“…Therefore, foliar application has been a recent technique that has provided improvements to must quality in relation to the amino acid and phenolic and volatile compound concentrations . Nevertheless, some studies have reported that the use of foliar applications can have little, or indeed negative, effects on grape berry quality …”

“…19 Nevertheless, some studies have reported that the use of foliar applications can have little, or indeed negative, effects on grape berry quality. [20][21][22] Elicitors have key roles in stimulation of the phenylpropanoid pathway and triggering of the activation of certain enzymes, such as phenylalanine ammonia-lyase, polyphenol oxidase, lipoxygenase and peroxidase. These can thus lead to the accumulation of phenolic compounds in different plant tissues.…”

Influence of Type of Management and Climatic Conditions on Productive Behavior, Oenological Potential, and Soil Characteristics of a ‘Cabernet Sauvignon’ Vineyard

“…Conventional viticulture disposes of agrochemicals such as inorganic fertilizers and synthetical chemical pesticides to the farming management, whereas these aforesaid products are banned in organic viticulture and only organic fertilizers and a certain non-synthetic pesticides are allowed in the agricultural management [4,5]. In organic viticulture, diseases control is mainly carried out using copper or sulfur treatment, while weed management is performed by tillage or grass-cutting [4,6,7]. Due to the high ability to adapt to the environment and its hardly manageable, weeds could affect productivity by competing with the vines [8].…”

Effects of anti‐transpirant di‐1‐p‐menthene, sprayed post‐veraison, on berry ripening of Sangiovese grapevines with different crop loads

“…A significant reduction in net photosynthesis and transpiration rate began to occur in early August, when the canopies were sprayed, resulting in lower TSS at harvest and an increase in anthocyanin concentration, without affecting TA. A previous study reported that the formation of the film from natural products can also provide a protective role against pathogen attack in other crops as well as grapevines (Garde-Cerdàn et al 2017).…”