Improving methods for evaluating potassium availability in vineyard soils

Abstract

Vineyard soils often contain mineralogy that can confound predictions of plantavailable potassium (K). Too little or too much K uptake into wine-grape (Vitis varieties) tissues can negatively affect fruit chemistry, making it important to have soil tests that accurately quantify plant-available K. Our goal was to determine the best soil sampling, processing, and extraction methods for predicting K availability in vineyard soils. We sampled soil and grapevine tissue in 39 vineyard blocks from 22 vineyards in Virginia, Maryland, and New Jersey. Plant tissue sampling included petioles at bloom and both petioles and leaf blades at veraison. Soil samples were collected from 0 to 10-and 0 to 38-cm depths. We tested three soil extraction methods-Mehlich 1, Mehlich 3, and sodium tetraphenylboron (NaTPB)-on both oven-dried and field-moist samples. The different sampling, processing, and extracting procedures produced distinct K concentrations, with shallow 0-10 cm samples and NaTPB extraction resulting in higher K concentrations than their counterparts. Upon drying, three soils fixed K and 24 samples released K. Whole leaf (petiole plus leaf blade) samples collected at veraison had the best relationships with most soil K concentrations. The best soil testing method for predicting tissue K concentration in whole leaves at veraison was Mehlich 1 extractions of field-moist soils from 0 to 38-cm depth. This sampling combination appears to be best suited for growers to use when assessing K concentrations in vineyard soils.

Modelación de la dormancia invernal de un viñedo en Linares, Nuevo León

“…La fecundación y fructificación se presenta a principios de mayo; las flores comienzan a dar pequeños frutos muy verdes, ya que están cargados de clorofila (Fiola, 2020;Kliewer, 1977;Liu et al, 2018). En esta etapa se limpia la vid podando los vástagos más largos, que son tallos nuevos que brotan al pie del tronco (cepa), y si la planta está cargada, se ejecutan las llamadas vendimias en verde o aclareos y se elimina una parte de los racimos jóvenes (Blouin, 2004).…”