Autoria: MOURA-BUENO, J. M.; CIOTTA, M. N.; BETEMPS, D. L.; FELIPPETO, J.; NAVA, G.; STEFANELLO, L. O.; TASSINARI A.; SCHMITT, D. S.; RAMOS, R. F.; BROWN, P. H.; BRUNETTO, G.

Resumo: Abstract Tropical and subtropical soils in vineyards show high phospho­rus (P) adsorption ability and, consequently, low P availability to plants. However, P critical levels (CL) and sufficiency ranges (SR) in soils and leaves in subtropical regions for yield and the must variables remain unknown. This study aimed to assess the yield response of ‘Cabernet Sauvignon’ grown in acidic soils with a high organic matter content in subtropical regions and to suggest CL and SR of P in the soil and leaves using bayesian change point quantile regression models. The study was carried out in the 2013/14, 2014/15, 2015/16, 2016/17, and 2017/18 crop sea­sons in a vineyard located in southern Brazil, treated with 0, 13, 26, 40, and 52 kg Pha-1 year-1, which were assessed. The P avail­ability in the soil was determined by Mehlich-1. The P in leaves (veraison), yield parameters, and must composition were eval­uated. Phosphate fertilizer applications to ‘Cabernet Sauvignon’ increased soil P, mainly on the soil surface. However, it did not increase the P concentration in leaves or influence yield or alter must pH and composition, such as pH, total soluble solids (TSS), total titratable acidity (TTA), and total polyphenols (TP). While P treatments had no effect on yield and fruit quality it was possible to utilize natural variation and Bayesian change point quantile regression models to determine CL’s for various attrib­utes. The CL of P in the 0-20 cm soil layer was 13.2 mg dm-3. The CL of P in leaves, regarding yield, TSS, and TTA, was 0.61, 0.88, and 0.52%, respectively.

Ano de publicação: 2025

Tipo de publicação: Artigo de periódico

Unidade: Embrapa Clima Temperado

Palavras-chave: Bayesian theory, Cultivo do Solo, Mosto, Must composition, Nutrient concentrations, Nutriente, Rendimento, Subtropical soils