Phosphorus forms in leaves and their relationships with must composition and yield in grapevines

Abstract

-The objective of this work was to evaluate phosphorus forms in grape leaves and their relationships with must composition and yield in grapevines grown in a Typic Hapludalf with different available P contents. Two experiments were carried out with Vitis vinifera cultivars, one with 'Tannat' and the other with 'Cabernet Franc' grapes. Experiment 1 consisted of two vineyards of 'Tannat', with the following P content in the soil: V1, 11.8 mg kg -1 P; and V2, 34.6 mg kg -1 P. Experiment 2 consisted of two vineyards of 'Cabernet Franc', with the following P content in the soil: V1, 16.0 mg kg -1 P; and V2, 37.0 mg kg -1 P. Leaves were collected at flowering (FL) and veraison (V), and, after their preparation, P forms were evaluated. Yield and must composition were assessed. The highest yield was observed in V2 of experiment 1 and in V2 of experiment 2. Total P content and P forms in leaves at FL and V have no relationship with yield parameters; however, total P content in leaves has a relationship with anthocyanin content in the must of 'Tannat' grapevines. Therefore, P fractionation in leaves predicts neither grapevine yield nor must composition.Index terms: Vitis vinifera, chemical fractionation of P in the tissue, grape production, must analysis, phosphorus fertilization. Formas de fósforo em folhas e suas relações com a composição do mosto e a produção em videirasResumo -O objetivo deste trabalho foi avaliar as formas de fósforo em folhas e suas relações com a composição do mosto e a produção em videiras cultivadas em um Argissolo Vermelho distrófico típico, com diferentes teores de P disponível. Dois experimentos foram realizados com cultivares de Vitis vinifera, um com uvas 'Tannat' e outro com 'Cabernet Franc'. O experimento 1 consistiu de dois vinhedos de 'Tannat', com os seguintes teores de fósforo no solo: V1, 11,8 mg kg -1 de P; e V2, 34,6 mg kg -1 de P. O experimento 2 consistiu de dois vinhedos de 'Cabernet Franc', com os seguintes teores de fósforo no solo: V1, 16,0 mg kg -1 de P; e V2, 37,0 mg kg -1 de P. Coletaram-se as folhas ao florescimento (FL) e ao início da maturação (IM), e, após a preparação delas, analisaram-se as formas de P. A produtividade e a composição do mosto foram avaliadas. A maior produtividade foi observada no V2 do experimento 1 e no V2 do experimento 2. O teor total de P e suas formas nas folhas ao FL e IM não apresentam relação com os parâmetros produtivos; no entanto, o teor de P total nas folhas apresenta relação com o teor de antocianinas no mosto de videiras 'Tannat'. Portanto, o fracionamento de P nas folhas não prediz a produtividade da videira nem a composição do mosto.Termos para indexação: Vitis vinifera, fracionamento químico de P no tecido, produção de uva, análise do mosto, adubação fosfatada.

Yield and must composition of grapevines subjected to phosphate fertilization in Southern Brazil

“…For this cultivar, there was a decreasing trend in total titratable acidity and tartaric acid concentration with increasing P rates, but an increasing one in pH, with significant differences only in 2011/2012. This behavioral trend in pH and total titratable acidity values was also observed by Piccin et al (2017a) for the 'Tannat' and 'Cabernet Franc' grapevines (V. vinifera), with significant differences. These results are most likely due to the greater P movement in the plant at flowering and veraison, as shown by the increase in leaf P concentration with increasing P rates applied to the soil (Table 2).…”

“…The decrease in total titratable acidity was 0.24 meq L -1 for each kilogram of P 2 O 5 applied to the soil; however, the decrease in tartaric acid in the must was only 0.002 meq L -1 for each kilogram of P 2 O 5 applied. This behavior was also shown in the data collected by Piccin et al (2017a), who did not identify a significant variation in the soluble solids contents, pH, and total titratable acidity of the studied grapes. However, these authors found important variations in phenolic composition -especially in total polyphenols and total anthocyanins -in relation to the P rates applied to the vineyard.…”

“…This is because total P is measured in the tissue analysis, which is not always adequate, because part of the P may not be metabolic and, therefore, may be allocated to reserve organelles, such as the vacuole; this non-metabolic P represents an additional uptake stored for future use (Piccin et al, 2017b). To determine P forms in the tissue, which could be part of metabolic P, total P should not be used, but rather ribonucleic acids and soluble inorganic P, since they may have a greater influence on grapevine yield parameters (Piccin et al, 2017a(Piccin et al, , 2017b. It was also observed that even when the soil in the area without P application was considered to have low or extremely low P availability (Silva et Pesq.…”

“…The Cabernet Sauvignon and Chardonnay cultivars stand out because of their suitable characteristics for the production of the fine quality wines -red and white, respectively -commonly grown in the high-altitude regions of Southern Brazil (Brighenti et al, 2013). It is believed that these cultivars may have different kinetic parameters related to P absorption, which may reflect in their different responses to fertilization (Piccin et al, 2017a).…”

Identification of the critical levels, sufficiency ranges and potential response to nutrient fertilization in vineyards by the DRIS method

“…However, viticulture involves fertilizer application: in Brazil, for instance, nearly 44% of the expenses are utilized for soil amendments such as acidity correctives accounting around 13% for the total cost of vineyard maintenance and production (>4 years) (IEG/FNP, 2017). Therefore, the fertilizer application must be monitored and used only when needed, and in judicious doses, to raise the soil nutrient availability necessary to maintain the requisite nutritional status (Ciotta et al, 2016) and to ensure a high quality and compensatory harvest (Piccin et al, 2017).…”